Antibioma

Antibioma is a Spanish word that means a local abscess, in the breast, produced or modified by prolonged antibiotic use.

http://wiki.answers.com/Q/Treatment_of_antibioma_in_dentistry

live conference on implantology from Jaipur on www.zerkonindia.com

Work with intention, not reaction and you and you're patient will both benefit.

They don't care how much you know, until they know how much you care.

Reverse Smile Line, found in old ages, due to attrition of incisors

Gull Shaped Smile Line seen in young Patients

Zenith of Gingival Contour is Slightly Distal

Links

http://discoveringdentistry.blogspot.com/

http://pe.dentpedia.info/

Photo: 9,000-Year-Old Drilled Teeth Are Work of Stone Age Dentists

Human teeth excavated from an archaeological site in Pakistan show that dentistry was thriving as recently as 9,000 years ago.

Researchers excavating a Stone Age graveyard found a total of 11 teeth that had been drilled, including one that had apparently undergone a complex procedure to hollow out a cavity deep inside the tooth.

The discovery suggests a high level of technological sophistication, though the procedure, which involved drills tipped with shards of flint, could hardly have been a painless affair.

"The finding provides clear and compelling evidence that earlier people had knowledge of manipulation of dental hard tissues in living people," said Clark Spencer Larsen, an anthropologist at Ohio State University in Columbus, who was not part of the excavation.

Scientists from the Université de Poitiers in Poitiers, France, and the Musée Guimet of Paris made the discovery.

The team's findings appear in this week's issue of the journal Nature.

Therapeutic Reason?

"We think the drilling had medical reasons," said Roberto Macchiarelli, a paleoanthropologist at the Université de Poitiers and lead author of the study.

"While some teeth had been drilled more than once, four showed signs of decay … suggesting a possible therapeutic intervention."

The procedure could not have had an aesthetic purpose, since its results were not easily visible, he added.

But the real motive is still uncertain.

"The reason is difficult to ascertain," said Jeffrey Schwartz, an anthropologist at the University of Pittsburgh in Pennsylvania.

"As the authors [of the study] admit, encroaching on the [tooth's] pulp cavity would cause pain, and leaving these holes so close to the pulp cavity, where they would accumulate food and lead to infection and continue to cause pain, would hardly seem to be therapeutic."

Macchiarelli's team made the discovery while excavating a 9,000-year-old graveyard in Baluchistan, a region of Pakistan that borders Afghanistan and Iran (map)

The people of Mehrgarh, the site of the dig, were once nomadic hunter-gatherers who settled into a more sedate lifestyle, growing crops and raising cattle.

During the dig, the researchers identified nine individuals with a total of 11 drilled teeth.

"One individual had three drilled teeth, while another had a tooth that had been drilled twice," Macchiarelli said.

A closer look with a microscope revealed that at least in one case, not only had the tooth been drilled, but the resulting cavity had also been delicately reshaped.

And in all cases, the researchers noticed smoothening of the teeth. That meant the drilling had been conducted on living people who then continued to use the teeth for chewing food.

Flint Drill

To make a hole on the relatively small surface of a tooth, Mehrgarh's dentists probably used a contraption quite similar to the one used in making a fire.

Rope from a bowlike device was looped around a slender piece of wood that was tipped with a sharp shard of flint. When the bow was moved sideways, it created a drill-like circular motion and pushed the flint into the tooth.

"It was very fast and also generated heat, enabling the dentist to drill holes smaller that 1 millimeter [0.04 inch] in diameter," said Macchiarelli, who created a replica of the drill by studying related artifacts.

He thinks that know-how for the early dentistry was probably transferred from artisans skilled at drilling holes in bead ornaments.

The researchers have yet to find evidence of dental fillings. Macchiarelli thinks that some sort of tarlike material or soft vegetable matter was stuffed into the tooth cavity. However, there is no evidence to prove the theory.

"[The fillings] could have degraded over time," he reasoned.

Out of Fashion

Though the dental manipulation lasted near Mehrgarh for about 1,500 years, the practice completely disappeared with the onset of the metal age about 7,000 years ago, Macchiarelli said.

"There is no evidence of this procedure in graveyards from much later periods, despite the continuation of poor dental health. We have no idea why it stopped," he said.

Schwartz, the Pittsburgh anthropologist, agreed the purpose of the drilling remains mysterious.

"In Pre-Columbian Mesoamerica, the lip-side surfaces of front teeth were drilled to receive semiprecious stones and gold, but that was clearly ornamental," he said.

"So I'm stumped as to why these holes were drilled."

Perhaps the pain caused the practice to lose popularity, he added.


Ref: http://news.nationalgeographic.com/news/2006/04/0405_060405_teeth_drill.html

IDEM INDIA

International Dental Exhibition & Meeting
Date: 23 to 25 Oct
Venue: Bombay Exhibition Centre, Goregaon East, Mumbai
Contact info: www.idem-india.com
Call: 9820448631

IDA@WDS ORGANISES A ORAL HEALTH CHECKUP

IDA@WORLD DENTAL SHOW S ORGANIZING A ORAL HEALTH CHECKUP CAMP TRYING TO CREATE A HISTORY IN THE WORLD OF DENTISTRY WITH 5000 CHECKUPS IN 24HRS TO BREAK THE GUINNESS RECORD.
ITS A 1 TIME OPPORTUNITY FOR ALL THE DOCS TO BE A PART OF THIS WORLD RECORD!ALL YOU HAVE 2 GIVE S A FEW HRS OF SERVICE FOR THE CAUSE!
AS IDA WOULD BE CREATING A DATABASE OF AL THE DOCS WHO HAVE BEEN A PART OF THE EVENT AND IF THE WORLD RECORD IS SUCCESSFULLY BROKEN THEN ALL THE DOCS WILL BE SENT A CERTIFICATE FOR BEING A PART OF THE GUINNESS BOOK OF WORLD RECORDS!
CONTACT DR. MAYANK DOSHI ON 9833091912. EMAIL ID:
drmayank18@gmail.com

START TIME: Friday, 09 October 2009 at 11:00
END TIME: Saturday, 10 October 2009 at 11:00
LOCATION: WORLD DENTAL SHOW, BANDRA KURLA COMPLEX.

Blind Woman's Tooth Helped Restore Her Sight

Interesting!!!!!

http://www.medicalnewstoday.com/articles/164221.php

The 6th World Congress of the International Federation of Esthetic Dentistry

When: August 2-5, 2009

Where: The Bellagio Resort, Las Vegas, Nevada, USA

Registration:

Please register for the event by visiting the following site: www.IFED2009.org

Pre-register before July 26, 2009 to avoid the on-site registration $200 surcharge.

Dentists, residents, students, and dental laboratory technicians are invited to present a Poster Presentation at the 6th World Congress of the International Federation of Esthetic Dentistry, August 2-5, 2009 at The Bellagio in Las Vegas, Nevada USA.

Posters will be displayed in our high-traffic exhibit hall from Monday, August 3 through Wednesday, August 5.

Awards will be presented to the top three posters.

Please visit www.IFED2009.org
for further information about the poster program.

Flossing Technique

Dr. Keki Turel Invite

First aid for toothache

To handle the pain while you wait to see the dentist, take paracetamol or ibuprofen. However, if you have a history of liver or kidney problems or peptic ulcers, or suffer from asthma, ibuprofen is not recommended for you. Also, avoid very hot and cold foods and drinks, because they worsen the problem.
Prevention is better than cure...

Toothache can easily be prevented by maintaining good dental hygiene practices.

* Cut down the amount of sugar in your diet. Excessively sweet foods and drinks should be consumed only occasionally.
* Follow a twice-a-day brushing routine, using a fluoride-containing toothpaste. Remember to brush your gums and tongue.
* Use dental floss to clean between your teeth, and a mouthwash to rinse your mouth.
* Avoid smoking
* Get your teeth check regularly, and have them cleaned at least once a year by a dental hygienist.

A guide to toothache and how to deal with it


What is toothache?


Toothache is a painful condition in your jaw and facial area.
It usually occurs when a nerve in the tooth root is inflamed or irritated.
It could also occur because of tooth decay, infection or even tooth loss.



Types of toothache

Everybody doesn’t experience the same kind of toothache, and very often a toothache can be a sign of a much deeper condition.
The severity of the toothache may also vary, in terms of the sensitivity of the tooth and the pain intensity.
No matter what type of toothache you suffer from, you should get it evaluated by a dentist.



Sharp tooth pain or sensitivity

When your teeth become extremely sensitive to cold, causing a sharp pain when you eat or drink very cold items, it could be due to loss of tooth enamel.
This deterioration of tooth enamel occurs because of excessive brushing, as a natural part of the aging process, recession of the gums or the deterioration of a tooth cavity.

If your teeth are overly sensitive to heat, this could be because of dental cavities, abscesses or a severely decayed tooth.



Chronic toothache

A consistently aching tooth can be the result of nerve damage.
The nerves of the tooth may get damaged because of severe dental decay or because of excessive grinding of the teeth.
It could also occur because of any kind of injury or trauma to the tooth.



Excruciating pain

Intense, agonizing pain, including a throbbing sensation, is most often because of an abscess or dental infection.
Very often, when the pain is this intense, there is also a noticeable swelling in the face.

If you experience pain while eating, it could be either due to a crack in the tooth or dental decay.



Pain the in back of the jaw
If the pain is mainly concentrated in the back of the jaw, it could be due to impacted back molars.
People, who have a habit of grinding their teeth or TMD can also experience jaw pain.



Serious health issues

A little known fact is that a toothache can often be a symptom of serious underlying health problems.
Studies have shown that a pain on the left side of the jaw can be the first sign of a heart attack.
Your toothache can also be a sign of sinus infection.
Inflammation of the jaw, and pain while eating can be one of the earliest symptoms of a maxillofacial condition called temporomandibular joint disorder (TMD).



Symptoms of toothache

The symptoms of toothache can manifest themselves suddenly, and can range from simple discomfort in your tooth to high intensity pain.
At one end, you could have a mild irritation, while on the other, you may experience intense pain in your jaw, head and ear.
The pain may worsen when you eat or drink, especially if what you are consuming is very hot or cold.
Toothache can quickly spread to the entire jaw area, making it tender and sensitive. You may notice that the pain worsens when you lie down, because of the increased pressure on the tooth.



Generally, you will notice:

* Sensitivity to hot or cold foods and drinks.
* Bleeding in the gums or around the tooth.
* Swelling of the tissue around the tooth.
* Swelling of the jaw.
* Pain while eating.



Causes of toothache

* Dental caries.
* Tooth cavities.
* Tiny tooth fracture.
* Exposed root of the tooth – this can happen when the gums recede, exposing the root.
* Sensitivity – this can also be caused by gum recession, which leaves the sensitive areas of the teeth exposed.
* Dental treatment – sometimes after a dental treatment, the tooth pulp may become irritated, leading to pain.
* A periodontal abscess in the gum.
* Acute ulcerative gingivitis, which causes ulcers on the gums.
* Sinusitis, which can lead to pain in the upper jaw.
* Inflamed gums around a tooth that a just beginning to emerge, like a wisdom tooth.
* Temporomandibular joint injury – this is the joint that connects the jaw to the skull.
* Teething – when babies and children begin to sprout new teeth, this can cause toothache.




Diagnosis of toothache...isn't it obvious?

Even if the toothache you are suffering from is mild, you must get it checked by a dentist immediately. Very often, pain in a tooth has got nothing to do with that tooth. The pain could easily be in another tooth, or in some cases, the other jaw. Your dentist will conduct an examination of your teeth, and look for signs of any damage to the tooth or inflammation. He may also look for sensitivity to heat. If your dentist suspects dental decay, jaw bone injuries, or minute fractures in your teeth, he will take an X-ray before he can confirm these conditions.

Tooth Ache

Toothache can be a sign of tooth decay. Only a Dental doctor can find the real cause of the pain. But let's try out some ways at home to control the pain.



Apply a little clove oil to the effected tooth or area.


When there is pain, take a piece of ice and press it against the skin between your thumb and forefinger.



Have lots of milk and leafy vegetables and calcium. Avoid sweet, sour and cold things which causes tooth decay.


When you have pain , never apply heat on your cheeks. If you are having an infection of the tooth applying heat will aggravate it.

What is sunday bite in orthodontics?

A sunday bite is when someone with a more pronounced upper jaw juts the chin (lower jaw) forward to make the upper jaw look less pronounced.

Tips for Dealing with Dental Emergencies

Bitten Lip or Tongue
Clean the area gently with a cloth and apply cold compresses to reduce any swelling. If the bleeding doesn’t stop, go to a hospital emergency room immediately.


Broken Tooth.
Rinse your mouth with warm water to clean the area. Use cold compresses on the area to keep any swelling down. Call your dentist immediately


Jaw-Possibly Broken
Apply cold compresses to control swelling. Go to your dentist or a hospital emergency department immediately.


Knocked Out Tooth
Hold the tooth by the crown and rinse off the root of the tooth in water if it’s dirty. Do not scrub it or remove any attached tissue fragments. If possible, gently insert and hold the tooth in its socket. If that isn’t possible, put the tooth in a cup of milk and get to the dentist as quickly as possible. Remember to take the tooth with you!




Toothache
Rinse your mouth with warm water to clean it out. Gently use dental floss or an interdental cleaner to ensure that there is no food or other debris caught between the teeth. Never put aspirin or any other painkiller against the gums near the aching tooth because it may burn the gum tissue. If the pain persists, contact your dentist.


Objects Caught Between Teeth
Try to gently remove the object with dental floss; avoid cutting the gums. Never use a sharp instrument to remove any object that is stuck between your teeth. If you can’t dislodge the object using dental floss, contact your dentist.

EMBLEM/INSIGNIA OF DENTISTRY

This dental insignia was adopted by the American Dental Association in November 1965 as the official emblem of dentistry.

The design uses as its central figure a serpent entwined about an ancient Arabian cautery in the manner of the single serpent of Aesculapius, the Greek god of medicine, coiled about a rod.

The Greek letter Δ (delta), for dentistry, and the Greek letter Ο (omicron), for odont (tooth) form the periphery of the design.

In the background of the design are 32 leaves and 20 berries, representative of the permanent and temporary teeth.

The suggested colors for the insignia are: the background, a shade of lilac—the official academic color of dentistry; the letter Ο in gold; the letter Δ in black; the cautery in gold outlined in black, and the leaves, berries and serpent merely outlined in black on the lilac background.

The National Association of Dental Faculties in 1897 chose the color lilac as the profession’s major color.
The color trims dental schools’ graduation gowns and caps and may be found in dental banners, emblems, insignia, signs, symbols and publications.

LECTURE ON SMILE DESIGNING

by Dr. Mona Kakkar
on 10th May
at Orchid Hotel, Near santacruz airport,Santacruz East,Mumbai
From 9.a.m to 6.p.m.

for registration contact
3M

LECTURE ON IMPLANT

IDA has arranged a lecture on

Implants by Dr. Ajit Shetty & Dr. Ajay Kakkar
Esthetic dentistry by Dr. Mukul Dhabolkar

on 10th May, Sunday
at Bandra Holy Cross Hospital, Morello hall, Bandra West
from 9.a.m to 2.p.m

Registration
for IDA members Rs 700/- till 5th May
for non IDA memb & spot registration Rs 900/-

for further information, contact Dr. Sharif Firoz 9821204545, 25033994

www.bhavatidentalclinic.webs.com

Hi friends,

My humble greetings to all!

Thanks for all your co-operation & support.

I humbly request you all to actively participate & give feedbacks...
This will help serving the purpose to create this blog.


Regards
Dr. Bhavati J. Lukka

DENTAL IMPLANT

INTRODUCTION
A dental implant is an artificial tooth root replacement and is used in prosthetic dentistry to support restorations that resemble a tooth or group of teeth.

The most widely accepted and successful implant today is the osseointegrated implant, based on the discovery by Swedish Professor Per-Ingvar Brånemark that titanium can be successfully fuse to bone when osteoblasts grow on rough surface of the implanted titanium.
This forms a structural and functional connection between the living bone and the implant.


HISTORY

The Mayan civilization has been shown to have used the earliest known examples of endosseous implants (implants embedded into bone), dating back over 1,350 years before Per-Ingvar Brånemark started working with titanium.
While excavating Mayan burial sites in Honduras in 1931, archaeologists found a fragment of mandible of Mayan origin, dating from about 600 AD.
This mandible, which is considered to be that of a woman in her twenties, had three tooth-shaped pieces of shell placed into the sockets of three missing lower incisor teeth.
For forty years the archaeological world considered that these shells were placed under the nose in a manner also observed in the ancient Egyptians.
However, in 1970 a Brazilian dental academic, Professor Amadeo Bobbio studied the mandibular specimen and took a series of radiographs.
He noted compact bone formation around two of the implants which led him to conclude that the implants were placed during life.

In the 1950s research was being conducted at Cambridge University in England to study blood flow in vivo.
These workers devised a method of constructing a chamber of titanium which was then embedded into the soft tissue of the ears of rabbits.

In 1952 the Swedish orthopaedic surgeon, P I Brånemark, was interested in studying bone healing and regeneration, and adopted the Cambridge designed ‘rabbit ear chamber’ for use in the rabbit femur.
Following several months of study he attempted to retrieve these expensive chambers from the rabbits and found that he was unable to remove them. Per Brånemark observed that bone had grown into such close proximity with the titanium that it effectively adhered to the metal.
Brånemark carried out many further studies into this phenomenon, using both animal and human subjects, which all confirmed this unique property of titanium.
Although he had originally considered that the first work should centre on knee and hip surgery, Brånemark finally decided that the mouth was more accessible for continued clinical observations and the high rate of edentulism in the general population offered more subjects for widespread study.
He termed the clinically observed adherence of bone with titanium as ‘osseointegration’.
In 1965 Brånemark, who was by then the Professor of Anatomy at Gothenburg University in Sweden, placed the first titanium dental implant into a human volunteer, a Swede named Gösta Larsson.
Over the next fourteen years Brånemark published many studies on the use of titanium in dental implantology until in 1978 he entered into a commercial partnership with the Swedish defense company, Bofors AB for the development and marketing of his dental implants.
With Bofors (later to become Nobel Industries) as the parent company, Nobelpharma AB (later to be renamed Nobel Biocare) was founded in 1981 to focus on dental implantology.
To the present day over 7 million Brånemark System implants have now been placed and hundreds of other companies produce dental implants.
The majority of dental implants currently available are shaped like small screws, with either tapered or parallel sides.
They can be placed at the same time as a tooth is removed by engaging with the bone of the socket wall and sometimes also with the bone beyond the tip of the socket.

Some current research in dental implantology is focusing on the use of ceramic materials such as zirconia (ZrO2) in the manufacture of dental implants. Although generally the same shape as titanium implants zirconia, which has been used successfully for orthopaedic surgery for a number of years, has the advantage of being more cosmetically aesthetic owing to its bright tooth-like colour. Long-term clinical data is necessary before one-piece ZrO2 implants can be recommended for daily practice

"The hope for a cure for periodontal disease & other human maladies is much closer to fruition because of the acceleration of scientific knowledge bought about by dedicated intellectualism & a commitment to information technology"
- E.Barrie Kenney

There is now a strong evidence that periodontal disease can contribute to numerous health problems including pregnancy complications, heart disease, stroke & diabetes.

Course on Implantology by Dr. A.Kumarswamy

Course is spread in 3 modules: May 15, 16, 17 2009
May 22, 23, 24 "
August 14, 15, 16 "

Organized by Famdent PDP

Administrative office no: 65049697, 26744509/3641, 26732260

Behaviour management is very important in cases of children for a paediatric dentist for a successful dental treatment...the simple technique used by the paediatric dentist is the "TELL SHOW DO" technique (where the instruments to be used are first shown and described to the child),modeling (where the child is made to stand near another child showing a positive behaviour) during any dental procedure and systematic desensitization (where the least anxiety provoking instruments and treatment procedures are introduced first reserving the highest anxiety provoking ones on the later visits)

Double Impression Technique for Bleach Impressions

GC TOOTH MOUSSE

http://www.gcasia.info/content_GC_Tooth_Mousse.html

what are STEM CELLS????

Stem cells are cells found in most, if not all, multi-cellular organisms.

They are characterized by the ability to renew themselves through mitotic cell division and differentiating into a diverse range of specialized cell types.

Research in the stem cell field grew out of findings by Canadian scientists Ernest A. McCulloch and James E.

Till in the 1960s the two broad types of mammalian stem cells are: embryonic stem cells that are isolated from the inner cell mass of blastocysts, and adult stem cells that are found in adult tissues.

In a developing embryo, stem cells can differentiate into all of the specialized embryonic tissues.
In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing specialized cells, but also maintain the normal turnover of regenerative organs, such as blood, skin or intestinal tissues.

Stem cells can now be grown and transformed into specialized cells with characteristics consistent with cells of various tissues such as muscles or nerves through cell culture.
Highly plastic adult stem cells from a variety of sources, including umbilical cord blood and bone marrow, are routinely used in medical therapies. Embryonic cell lines and autologous embryonic stem cells generated through therapeutic cloning have also been proposed as promising candidates for future therapies.

Pluripotent, embryonic stem cells originate as inner mass cells within a blastocyst. The stem cells can become any tissue in the body, excluding a placenta. Only the morula's cells are totipotent, able to become all tissues and a placenta.

Properties


[plz click on the image to zoom it]



The classical definition of a stem cell requires that it possess two properties:

* Self-renewal - the ability to go through numerous cycles of cell division while maintaining the undifferentiated state.
* Potency - the capacity to differentiate into specialized cell types. In the strictest sense, this requires stem cells to be either totipotent or pluripotent - to be able to give rise to any mature cell type, although multipotent or unipotent progenitor cells are sometimes referred to as stem cells.

Potency definitions

Potency specifies the differentiation potential (the potential to differentiate into different cell types) of the stem cell.[4]

* Totipotent (a.k.a omnipotent) stem cells can differentiate into embryonic and extraembryonic cell types. Such cells can construct a complete, viable, organism.[4] These cells are produced from the fusion of an egg and sperm cell. Cells produced by the first few divisions of the fertilized egg are also totipotent.[citation needed]
* Pluripotent stem cells are the descendants of totipotent cells and can differentiate into nearly all cells,[4] i.e. cells derived from any of the three germ layers.[5]
* Multipotent stem cells can differentiate into a number of cells, but only those of a closely related family of cells (e.g. hematopoietic stem cells differentiate into red blood cells, white blood cells, platelets, etc.).[4]
* Oligopotent stem cells can differentiate into only a few cells, such as lymphoid or myeloid stem cells.[4]
* Unipotent cells can produce only one cell type, their own,[4] but have the property of self-renewal which distinguishes them from non-stem cells (e.g. muscle stem cells).

Identification

The practical definition of a stem cell is the functional definition - the ability to regenerate tissue over a lifetime. For example, the gold standard test for a bone marrow or hematopoietic stem cell (HSC) is the ability to transplant one cell and save an individual without HSCs. In this case, a stem cell must be able to produce new blood cells and immune cells over a long term, demonstrating potency. It should also be possible to isolate stem cells from the transplanted individual, which can themselves be transplanted into another individual without HSCs, demonstrating that the stem cell was able to self-renew.

Properties of stem cells can be illustrated in vitro, using methods such as clonogenic assays, where single cells are characterized by their ability to differentiate and self-renew.[6][7] As well, stem cells can be isolated based on a distinctive set of cell surface markers. However, in vitro culture conditions can alter the behavior of cells, making it unclear whether the cells will behave in a similar manner in vivo. Considerable debate exists whether some proposed adult cell populations are truly stem cells.

Embryonic

Main article: Embryonic stem cell

Embryonic stem cell lines (ES cell lines) are cultures of cells derived from the epiblast tissue of the inner cell mass (ICM) of a blastocyst or earlier morula stage embryos.[8] A blastocyst is an early stage embryo—approximately four to five days old in humans and consisting of 50–150 cells. ES cells are pluripotent and give rise during development to all derivatives of the three primary germ layers: ectoderm, endoderm and mesoderm. In other words, they can develop into each of the more than 200 cell types of the adult body when given sufficient and necessary stimulation for a specific cell type. They do not contribute to the extra-embryonic membranes or the placenta.

Nearly all research to date has taken place using mouse embryonic stem cells (mES) or human embryonic stem cells (hES). Both have the essential stem cell characteristics, yet they require very different environments in order to maintain an undifferentiated state. Mouse ES cells are grown on a layer of gelatin and require the presence of Leukemia Inhibitory Factor (LIF).[9] Human ES cells are grown on a feeder layer of mouse embryonic fibroblasts (MEFs) and require the presence of basic Fibroblast Growth Factor (bFGF or FGF-2).[10] Without optimal culture conditions or genetic manipulation,[11] embryonic stem cells will rapidly differentiate.

A human embryonic stem cell is also defined by the presence of several transcription factors and cell surface proteins. The transcription factors Oct-4, Nanog, and SOX2 form the core regulatory network that ensures the suppression of genes that lead to differentiation and the maintenance of pluripotency.[12] The cell surface antigens most commonly used to identify hES cells are the glycolipids SSEA3 and SSEA4 and the keratan sulfate antigens Tra-1-60 and Tra-1-81. The molecular definition of a stem cell includes many more proteins and continues to be a topic of research.[13]

After nearly ten years of research[14], there are no approved treatments or human trials using embryonic stem cells. ES cells, being pluripotent cells, require specific signals for correct differentiation - if injected directly into another body, ES cells will differentiate into many different types of cells, causing a teratoma. Differentiating ES cells into usable cells while avoiding transplant rejection are just a few of the hurdles that embryonic stem cell researchers still face.[15] Many nations currently have moratoria on either ES cell research or the production of new ES cell lines. Because of their combined abilities of unlimited expansion and pluripotency, embryonic stem cells remain a theoretically potential source for regenerative medicine and tissue replacement after injury or disease.

Adult

Main article: Adult stem cell

Stem cell division and differentiation. A - stem cell; B - progenitor cell; C - differentiated cell; 1 - symmetric stem cell division; 2 - asymmetric stem cell division; 3 - progenitor division; 4 - terminal differentiation

[plz click on the image to see it completely and to zoom it]

The term adult stem cell refers to any cell which is found in a developed organism that has two properties: the ability to divide and create another cell like itself and also divide and create a cell more differentiated than itself. Also known as somatic (from Greek Σωματικóς, "of the body") stem cells and germline (giving rise to gametes) stem cells, they can be found in children, as well as adults.[16]

Pluripotent adult stem cells are rare and generally small in number but can be found in a number of tissues including umbilical cord blood.[17] A great deal of adult stem cell research has focused on clarifying their capacity to divide or self-renew indefinitely and their differentiation potential.[18] In mice, pluripotent stem cells are directly generated from adult fibroblast cultures. Unfortunately, many mice don't live long with stem cell organs [19]

Most adult stem cells are lineage-restricted (multipotent) and are generally referred to by their tissue origin (mesenchymal stem cell, adipose-derived stem cell, endothelial stem cell, etc.).[20][21]

Adult stem cell treatments have been successfully used for many years to treat leukemia and related bone/blood cancers through bone marrow transplants.[22] Adult stem cells are also used in veterinary medicine to treat tendon and ligament injuries in horses.[23] The use of adult stem cells in research and therapy is not as controversial as embryonic stem cells, because the production of adult stem cells does not require the destruction of an embryo. Additionally, because in some instances adult stem cells can be obtained from the intended recipient, (an autograft) the risk of rejection is essentially non-existent in these situations. Consequently, more US government funding is being provided for adult stem cell research.[24]

Lineage

Main article: Stem cell line

To ensure self-renewal, stem cells undergo two types of cell division (see Stem cell division and differentiation diagram). Symmetric division gives rise to two identical daughter cells both endowed with stem cell properties. Asymmetric division, on the other hand, produces only one stem cell and a progenitor cell with limited self-renewal potential. Progenitors can go through several rounds of cell division before terminally differentiating into a mature cell. It is possible that the molecular distinction between symmetric and asymmetric divisions lies in differential segregation of cell membrane proteins (such as receptors) between the daughter cells.[25]

An alternative theory is that stem cells remain undifferentiated due to environmental cues in their particular niche. Stem cells differentiate when they leave that niche or no longer receive those signals. Studies in Drosophila germarium have identified the signals dpp and adherens junctions that prevent germarium stem cells from differentiating.[26][27]

Main article: Induced Pluripotent Stem Cell

The signals that lead to reprogramming of cells to an embryonic-like state are also being investigated. These signal pathways include several transcription factors including the oncogene c-Myc. Initial studies indicate that transformation of mice cells with a combination of these anti-differentiation signals can reverse differentiation and may allow adult cells to become pluripotent.[28] However, the need to transform these cells with an oncogene may prevent the use of this approach in therapy.

Treatments

Main article: Stem cell treatments

Medical researchers believe that stem cell therapy has the potential to dramatically change the treatment of human disease. A number of adult stem cell therapies already exist, particularly bone marrow transplants that are used to treat leukemia.[29] In the future, medical researchers anticipate being able to use technologies derived from stem cell research to treat a wider variety of diseases including cancer, Parkinson's disease, spinal cord injuries, Amyotrophic lateral sclerosis, multiple sclerosis, and muscle damage, amongst a number of other impairments and conditions.[30][31] However, there still exists a great deal of social and scientific uncertainty surrounding stem cell research, which could possibly be overcome through public debate and future research, and further education of the public.

Stem cells, however, are already used extensively in research, and some scientists do not see cell therapy as the first goal of the research, but see the investigation of stem cells as a goal worthy in itself.[32]

Controversy surrounding research

Main article: Stem cell controversy

There exists a widespread controversy over human embryonic stem cell research that emanates from the techniques used in the creation and usage of stem cells. Human embryonic stem cell research is controversial because, with the present state of technology, starting a stem cell line requires the destruction of a human embryo and/or therapeutic cloning. However, recently, it has been shown in principle that adult stem cell lines can be manipulated to generate embryonic-like stem cell lines using a single-cell biopsy similar to that used in preimplantation genetic diagnosis that may allow stem cell creation without embryonic destruction.[33] It is not the entire field of stem cell research, but the specific field of human embryonic stem cell research that is at the centre of an ethical debate.

Opponents of the research argue that embryonic stem cell technologies are a slippery slope to reproductive cloning and can fundamentally devalue human life. Those in the pro-life movement argue that a human embryo is a human life and is therefore entitled to protection.

Contrarily, supporters of embryonic stem cell research argue that such research should be pursued because the resultant treatments could have significant medical potential. It is also noted that excess embryos created for in vitro fertilization could be donated with consent and used for the research.

The ensuing debate has prompted authorities around the world to seek regulatory frameworks and highlighted the fact that stem cell research represents a social and ethical challenge.

Key research events

* 1908 - The term "stem cell" was proposed for scientific use by the Russian histologist Alexander Maksimov (1874–1928) at congress of hematologic society in Berlin. It postulated existence of haematopoietic stem cells.
* 1960s - Joseph Altman and Gopal Das present scientific evidence of adult neurogenesis, ongoing stem cell activity in the brain; their reports contradict Cajal's "no new neurons" dogma and are largely ignored.
* 1963 - McCulloch and Till illustrate the presence of self-renewing cells in mouse bone marrow.
* 1968 - Bone marrow transplant between two siblings successfully treats SCID.
* 1978 - Haematopoietic stem cells are discovered in human cord blood.
* 1981 - Mouse embryonic stem cells are derived from the inner cell mass by scientists Martin Evans, Matthew Kaufman, and Gail R. Martin. Gail Martin is attributed for coining the term "Embryonic Stem Cell".
* 1992 - Neural stem cells are cultured in vitro as neurospheres.
* 1997 - Leukemia is shown to originate from a haematopoietic stem cell, the first direct evidence for cancer stem cells.
* 1998 - James Thomson and coworkers derive the first human embryonic stem cell line at the University of Wisconsin-Madison.[34]
* 2000s - Several reports of adult stem cell plasticity are published.
* 2001 - Scientists at Advanced Cell Technology clone first early (four- to six-cell stage) human embryos for the purpose of generating embryonic stem cells.[35]
* 2003 - Dr. Songtao Shi of NIH discovers new source of adult stem cells in children's primary teeth.[36]
* 2004–2005 - Korean researcher Hwang Woo-Suk claims to have created several human embryonic stem cell lines from unfertilised human oocytes. The lines were later shown to be fabricated.
* 2005 - Researchers at Kingston University in England claim to have discovered a third category of stem cell, dubbed cord-blood-derived embryonic-like stem cells (CBEs), derived from umbilical cord blood. The group claims these cells are able to differentiate into more types of tissue than adult stem cells.
* August 2006 - Rat Induced pluripotent stem cells: the journal Cell publishes Kazutoshi Takahashi and Shinya Yamanaka.
Takahashi K, Yamanaka S (Aug 2006). "Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors". Cell 126 (4): 663–76. doi:10.1016/j.cell.2006.07.024. PMID 16904174. http://www.cell.com/content/article/fulltext?uid=PIIS0092867406009767.
* October 2006 - Scientists at Newcastle University in England create the first ever artificial liver cells using umbilical cord blood stem cells.[37][38]
* January 2007 - Scientists at Wake Forest University led by Dr. Anthony Atala and Harvard University report discovery of a new type of stem cell in amniotic fluid.[39] This may potentially provide an alternative to embryonic stem cells for use in research and therapy.[40]
* June 2007 - Research reported by three different groups shows that normal skin cells can be reprogrammed to an embryonic state in mice.[41] In the same month, scientist Shoukhrat Mitalipov reports the first successful creation of a primate stem cell line through somatic cell nuclear transfer[42]
* October 2007 - Mario Capecchi, Martin Evans, and Oliver Smithies win the 2007 Nobel Prize for Physiology or Medicine for their work on embryonic stem cells from mice using gene targeting strategies producing genetically engineered mice (known as knockout mice) for gene research.[43]
* November 2007 - Human Induced pluripotent stem cells: Two similar papers released by their respective journals prior to formal publication: in Cell by Kazutoshi Takahashi and Shinya Yamanaka, "Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors",[44] and in Science by Junying Yu, et al., from the research group of James Thomson, "Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells":[45] pluripotent stem cells generated from mature human fibroblasts. It is possible now to produce a stem cell from almost any other human cell instead of using embryos as needed previously, albeit the risk of tumorigenesis due to c-myc and retroviral gene transfer remains to be determined.
* January 2008 - Robert Lanza and colleagues at Advanced Cell Technology and UCSF create the first human embryonic stem cells without destruction of the embryo[46]
* January 2008 - Development of human cloned blastocysts following somatic cell nuclear transfer with adult fibroblasts[47]
* February 2008 - Generation of Pluripotent Stem Cells from Adult Mouse Liver and Stomach: these iPS cells seem to be more similar to embryonic stem cells than the previous developed iPS cells and not tumorigenic, moreover genes that are required for iPS cells do not need to be inserted into specific sites, which encourages the development of non-viral reprogramming techniques. [48][49]
* March 2008-The first published study of successful cartilage regeneration in the human knee using autologous adult mesenchymal stem cells is published by Clinicians from Regenerative Sciences[50]
* October 2008 - Sabine Conrad and colleagues at Tübingen, Germany generate pluripotent stem cells from spermatogonial cells of adult human testis by culturing the cells in vitro under leukemia inhibitory factor (LIF) supplementation. [51]
* 30 October 2008 - Embryonic-like stem cells from a single human hair.[52]

Funding & policy debate in the US

* 1993 - As per the National Institutes of Health Revitalization Act, Congress and President Bill Clinton give the NIH direct authority to fund human embryo research for the first time.[53]
* 1995 - The U.S. Congress passes an appropriations bill attached to which is a rider, the Dickey Amendment which prohibited federally appropriated funds to be used for research where human embryos would be either created or destroyed. President Clinton signs the bill into law. This predates the creation of the first human embryonic stem cell lines.
* 1999 - After the creation of the first human embryonic stem cell lines in 1998 by James Thomson of the University of Wisconsin, Harriet Rabb, the top lawyer at the Department of Health and Human Services, releases a legal opinion that would set the course for Clinton Administration policy. Federal funds, obviously, could not be used to derive stem cell lines (because derivation involves embryo destruction). However, she concludes that because human embryonic stem cells "are not a human embryo within the statutory definition," the Dickey-Wicker Amendment does not apply to them. The NIH was therefore free to give federal funding to experiments involving the cells themselves. President Clinton strongly endorses the new guidelines, noting that human embryonic stem cell research promised "potentially staggering benefits." And with the guidelines in place, the NIH begins accepting grant proposals from scientists.[53]
* 02 November, 2004 - California voters approve Proposition 71, which provides $3 billion in state funds over ten years to human embryonic stem cell research.
* 2001–2006 - U.S. President George W. Bush signs an executive order which restricts federally-funded stem cell research on embryonic stem cells to the already derived cell lines. He supports federal funding for embryonic stem cell research on the already existing lines of approximately $100 million and $250 million for research on adult and animal stem cells.
* 5 May, 2006 - Senator Rick Santorum introduces bill number S. 2754, or the Alternative Pluripotent Stem Cell Therapies Enhancement Act, into the U.S. Senate.
* 18 July, 2006 - The U.S. Senate passes the Stem Cell Research Enhancement Act H.R. 810 and votes down Senator Santorum's S. 2754.
* 19 July, 2006 - President George W. Bush vetoes H.R. 810 (Stem Cell Research Enhancement Act), a bill that would have reversed the Dickey Amendment which made it illegal for federal money to be used for research where stem cells are derived from the destruction of an embryo.
* 07 November, 2006 - The people of the U.S. state of Missouri passed Amendment 2, which allows usage of any stem cell research and therapy allowed under federal law, but prohibits human reproductive cloning.[54]
* 16 February, 2007 – The California Institute for Regenerative Medicine became the biggest financial backer of human embryonic stem cell research in the United States when they awarded nearly $45 million in research grants.[55]
* 04 November, 2008 - The people of the U.S. state of Michigan passed Proposal 08-2, allowing Michigan researchers to make embryonic stem cell cultures from excess embryos donated from fertility treatments.[56]
* 23 January, 2009 - Under the new President Barack Obama, the restrictions placed on federal funding of Stem Cell research in the United States were lifted.[57]


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External links

General

* Tell Me About Stem Cells: Quick and simple guide explaining the science behind stem cells
* Stem Cell Basics
* Nature Reports Stem Cells: Introductory material, research advances and debates concerning stem cell research.
* Understanding Stem Cells: A View of the Science and Issues from the National Academies
* Scientific American Magazine (June 2004 Issue) The Stem Cell Challenge
* Scientific American Magazine (July 2006 Issue) Stem Cells: The Real Culprits in Cancer?
* National Institutes of Health
* Stem Cell Research Forum of India
* Ethics of Stem Cell Research entry in the Stanford Encyclopedia of Philosophy by Andrew Siegel
* Isolation of amniotic stem cell lines with potential for therapy

Peer-reviewed journals

* STEM CELLS
* Cytotherapy
* Cloning and Stem Cells
* Stem Cells and Development
* Regenerative Medicine
* Stem Cell Research

STEM CELL BANK SOURCE--DECIDUOUS (MILK) TEETH & WISDOM TEETH

[plz click on the image to zoom it]


WORLD'S 1ST BABY TOOTH STEM CELL BANK


BioEden (registered with the FDA), is the first fully operational processing laboratory and storage bank for primary teeth stem cells to open in the U.S. Their state-of-the-art facilities are located in Austin, Texas, and will serve children and their families nationwide. BioEden is also the only cell storage facility willing to guarantee their services.

The stem cells found in children’s primary teeth are a viable, ethical, and morally non-controversial alternative to the possibilities offered by embryonic stem cells. BioEden, Inc. was founded to bring this exciting technology to the American public at an affordable price.

According to President Jeff Johnson, the process is simple, when your child’s tooth begins to loosen, call them. They will send you a kit with processing instructions, and make arrangements to have the tooth transported to their facility in Austin, Texas where the cells contained in the tooth will be removed and stored in a special process that keeps them viable for the future. It is critical that the cells be extracted quickly after the tooth falls out, and there are only 12 teeth that can be used for this process — not every tooth contains cells with this potential.

Dr. Songao Shi, Principle Investigator of the Dental Biology Unit at the National Institute of Health, identified adult stem cells in primary children’s teeth in 2003. Progenitor cells discovered include adiposites, osteoblasts, chondracytes, and mesenchymal stem cells. These types of cells are all being investigated for their ability to therapeutically treat many human diseases including heart disease, bone regeneration, and most promisingly neuronal degenerative disorders such as Alzheimer’s, Parkinson’s, and spinal cord injury.


In a major breakthrough in stem cell study researchers find human teeth can be a potential source of stem cell. Researchers are very sure about the source, so much that two US companies have offered special jar to preserve human teeth that are no more in use. Unfortunately, they find no users so far.

One such company is StemSave. The company charges a one-time fee of $590 and annual fees of $100 for storage.

Researchers have found that human exfoliated deciduous teeth had cells that showed positive results in tests with mice. So the exfoliated teeth may be an unexpected unique resource for stem-cell therapies including autologous stem-cell transplantation and tissue engineering.

However, others says that freezing teeth is no exception.It is similar to current practice of freezing sperm, eggs or embryos for future use, or maybe more like freezing the body or head of dead people in the hope that future technology will find a way to make it worth the trouble.

Source: Newsok


Someday, dentists might be able to repair cavities with stem cells instead of synthetic fillings. And on the "long-term horizon," dental stem cells might be used to regrow teeth for people who otherwise would need dentures, Stansbury said.

DIFFERENT WAYS OF STAGING CANCERS

There are different ways of staging cancers. The two main ways are the TNM system and number system.


TNM stages of mouth and oropharyngeal cancers

‘TNM’ stands for Tumour, Node and Metastasis. The system describes

* The size of a primary tumour (T)
* Whether the cancer has spread to the lymph nodes (N)
* Whether the cancer has spread to a different part of the body (M)

‘T’ stages of mouth cancer

There are 4 main 'T' stages of mouth and oropharyngeal cancer

* T1 means the tumour is contained within the tissue of the mouth or oropharynx and is no larger than 2cm (3/4 inch)
* T2 means the tumour is larger than 2cm, but smaller than 4cm (about 1 ½ inches)
* T3 means the tumour is bigger than 4cm
* T4 means the tumour has grown further than the mouth or oropharynx and into nearby body tissues such as bone, tissues of the neck, neck muscles, tongue, skin, sinuses or the voice box (larynx)

‘N’ stages of mouth cancer

There are 4 main lymph node stages in cancer of the mouth and oropharynx. One of these, stage N2, is broken down into 3 sub-stages. The important points here are whether there is cancer in any of the lymph nodes and if so, the size of the node and which side of the neck it is on.

* N0 means there are no cancer cells in the lymph nodes
* N1 means there are cancer cells in 1 lymph node on the same side of the neck as the cancer, but the node is less than 3cm across
* N2a means there is cancer in 1 lymph node on the same side of the neck, and the node is more than 3cm across but less than 6cm across
* N2b means there is cancer in more than 1 lymph node, but none of these nodes are more than 6cm across. All the affected nodes are on the same side of the neck as the cancer.
* N2c means there is cancer in nodes on the other side of the neck, or in nodes on both sides, but none of these nodes are more than 6cm across
* N3 means that at least 1 node containing cancer is more than 6cm across

‘M’ stages of mouth cancer

There are two stages to describe spread of cancer of the mouth and oropharynx to other parts of the body

* M0 means there is no cancer spread to other parts of the body
* M1 means the cancer has spread to other parts of the body, such as the lungs

Together, the T, N and M stages give a complete description of the stage of your cancer. For example, if you have a T2, N0, M0 cancer, you have a tumour larger than 2cm but not larger than 4cm. The lymph nodes are clear and there is no spread of your cancer to other parts of the body.

Number stages of mouth cancers

There are four main stages in this system – stages 1 to 4. Some doctors also refer to stage 0.

Stage 0 or carcinoma in situ (CIS)

If you have CIS or stage 0 cancer of the mouth, you have a very early stage cancer. Some doctors prefer to call this pre-cancer. There are cancer cells there. But they are all contained entirely within the lining of the mouth or oropharynx. So they have not spread. As the cells have not spread, this is not yet a true cancer. If the pre-cancer is not treated, there is a high chance of this condition going on to develop into an invasive cancer.

Stage 1
This is the earliest stage of invasive cancer. It means that cancer has begun to grow through the tissues lining the mouth and into the deeper tissues underneath. The cancer is no more than 2 cm across and has not spread to nearby tissues, lymph nodes or other organs.

Stage 2
If you have stage 2 mouth cancer, the tumour is larger than 2 cm across, but less than 4cm. The cancer has not spread to lymph nodes or any other organs.

Stage 3

Having stage 3 mouth cancer can mean one of two things. Either the cancer is bigger than 4cm but has not spread to any lymph nodes or other parts of the body. Or the tumour is any size but has spread to one lymph node on the same side of the neck as the cancer. In this case the lymph node involved is no more than 3cm across.

Stage 4

This means the cancer is advanced. Stage 4 can mean one of 3 things

* The cancer has grown through the tissues around the lips and mouth - lymph nodes in the area may or may not contain cancer cells
* The cancer is any size and has spread to more than 1 lymph node on the same side of the neck as the cancer, or to lymph nodes on both sides of the neck, or to any lymph node that is bigger than 6cm
* The cancer has spread to other parts of the body such as the lungs or bones

The different grades of mouth and oropharyngeal cancer

The grade of a cancer tells you what the cells look like under a microscope. ` They are 'graded' according to how normal or abnormal they appear. There are 4 grades of oral and oropharyngeal cancer cells

* Grade 1 (low grade) – the cancer cells look very much like normal mouth or oropharyngeal
* Grade 2 (intermediate grade) – the cancer cells look slightly like normal mouth or oropharyngeal cells
* Grade 3 (high grade) – the cancer cells look very abnormal and not much like normal mouth or oropharyngeal cells
* Grade 4 (high grade) - the cancer cells do not look anything like normal mouth or oropharyngeal cells

Differentiation means how developed or mature a cell is. So you may hear your doctor describe grade 1 cancer cells as 'well differentiated'. Grade 2 cancer cells are 'moderately differentiated'. Grade 3 cancer cells are 'poorly differentiated'.

The grade of the cancer gives your specialist a 'rule of thumb' as to how the cancer is likely to behave. Low grade cancers are usually slower growing and less likely to spread. High grade cancers are likely to be faster growing and more likely to spread. This is only a guide. Your specialist will consider all your test results when deciding which treatment options are best for you.

EARLY IDENTIFICATION OF ABNORMAL SYMPTOMS IN MOUTH

It is important to have a self-awareness and to perform regular, self-examinations to help in the early identification of these symptoms:

1. A sore or ulcer in the mouth that does not heal within three weeks

2. A lump or overgrowth of tissue anywhere in the mouth

3. A white or red patch on the gums, tongue, or lining of the mouth

4. Difficulty in swallowing

5. Difficulty in chewing or moving the jaw or tongue

6. Numbness of the tongue or other area of the mouth

7. A feeling that something is caught in the throat

8. A chronic sore throat or hoarseness that persists more than six weeks, particularly smokers over 50 years old and heavy drinkers

9. Swelling of the jaw that causes dentures to fit poorly or become uncomfortable

10. Neck swelling present for more than three weeks

11. Unexplained tooth mobility persisting for more than three weeks - see a dentist urgently

12. Unilateral nasal mass / ulceration / obstruction, particularly associated with purulent or bloody discharge

Crown down Pressureless Technique

Begin at the coronal portion with Gates-Gliddens

Continue down the canal, reducing the size of each file as you get closer to the apex

Your goal is to achieve a funnel shape

Description: In the crown down technique the dentist essentially works from the crown of the tooth, shaping the canal as he or she moves towards the apex. The instruments are used in a large to small sequence. The first instruments are the Gates-Gliddens which do the coronal flaring. The Peeso reamers or Hedstrom files follow in the mid-root region. Finally, progressively smaller files take the dentist towards the apex.





1. Insert #35 file until it just binds and measure depth - this is the “radicular access length”

2. Flare coronal portion of canal using #2 and #3 Gates to radicular access length

3. Starting with #30 file, insert beyond radicular access length until resistance first encountered

4. Rotate #30 clockwise two full rotations using NO pressure

5. Step down using sequentially smaller files rotated as in #4 above to a point 3mm from the radiographic apex. This is the “provisional working length”. Take a radiograph with the file at the provisional WL and estimate your “true” WL.

6. Continue stepping down with smaller files to the true WL

7. Place a #35 file until resistance is just met (should be at or beyond your radicular access length)

8. Rotate passively two full turns and then proceed with smaller files in step-down to the true WL

Coronal Flaring

The concept of Coronal Flaring came as a major breakthrough in endodontics. Instead of heading directly to the apical area, this approach cleaned up the coronal part, of thousands of micro organisms, thus preventing their entry to the apical part. But an unfortunate thing that has happened is that while so much stress is being given to the coronal enlargement, the apical area has been neglected.

Instrument Removal System

This system is a breakthrough endodontic device designed to mechanically engage and remove many intracanal obstructions.

EndoActivator System

The EndoActivator was developed by Drs. Pierre Machtou, Bob Sharp and Cliff Ruddle, and is designed to safely and vigorously energize the hydrodynamic phenomenon. Activated fluids promote deep cleaning and disinfection. Complete cleaning facilitates 3-D endodontics and long-term success.

Endodontic Microbrushes

Rotary tapered microbrushes may be used with various irrigants to optimally finish a root canal preparation following shaping procedures.

during extraction of a tooth if root tip breaks, easiest way is to screw in a headstrom file and root tip easily comes out. And do you know what file size is normally used ? 35 yes that shows the canal size in apical area is larger than 35 (Ref is JADA: STONER 133 (4): p 473, 2002)

ProTaper®Universal Rotary Instruments

ProTaper® Universal SEM of
Active Cutting Surface







ProTaper® Universal nickel titanium rotary files are specially designed to instrument difficult, highly calcified, and severely curved root canals. The patented progressive taper, and advanced flute design provide the flexibility and efficiency to achieve consistent, successful cleaning and shaping when faced with these challenges


The finishing files, or F1, F2, F3, F4 and F5 instruments, have been designed to optimally finish the apical one-third, they do subtly and progressively expand the shape in the middle one-third of the canal. Generally, only one finishing instrument is required to prepare the apical one-third of a canal and the one selected is based on the canal's curvature and cross-sectional diameter.

The SX or Shaping X file is an accessory file and is used to optimally shape canals in shorter roots, relocate canals away from external root concavities, and to produce more shape, as desired, in the coronal aspects of canals in longer roots.

X GATE

Use this unique instrument to experience all the advantages of Gates 1-4 with maximal efficiency and simplicity. X-Gates features: • The tip of Gates 1 for easy insertion of the drill into the coronal third of the root canal. • The maximum diameter of Gates 4 for efficient relocation of the root canal opening. • The shaft of Gates 3 for improved strength. Use with a brushing action on the withdrawal stroke to intentionally relocate the canal away from the furcal danger. Also use to flatten, widen and finish the internal axial walls. In addition, its abrasively coated rounded tip enables you to precisely finish the pulpal floor.

ENDOACTIVATOR

The EndoActivator® System is designed to safely and vigorously energize the hydrodynamic phenomenon. Activated fluids promote deep cleaning and disinfection into lateral canals, fins, webs, and anastomoses. A cleaned root canal system facilitates 3-D obturation and long-term success. Activate your endodontic solutions today with this easy-to-use technology!

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www.endoruddle.com

Biopsy

A biopsy (in Greek: βίος life and όψη look/appearance) is a medical test involving the removal of cells or tissues for examination. It is the removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy. When only a sample of tissue is removed with preservation of the histological architecture of the tissue's cells, the procedure is called an incisional biopsy or core biopsy. When a sample of tissue or fluid is removed with a needle in such a way that cells are removed without preserving the histological architecture of the tissue cells, the procedure is called a needle aspiration biopsy.




oral lesions whose diagnosis can be made relying on data gathered during the history and/or physical examination, but there are others where histopathological studies are needed to confirm the presumed clinical diagnosis.

Biopsy is a surgical procedure to obtain tissue from a living organism for its microscopical examination, usually to perform a diagnosis





Objectives

The aim of the biopsy is to:

• define a lesion on the basis of its histopathological aspect;

• to establish a prognosis in malignant or premalignant lesions;

• facilitate the prescription of specific treatment;

• contribute to the assessment of the efficacy of the treatment;

• act as a document with medical-legal value.



Indications

Biopsy is indicated for diagnostic confirmation of suspected malignant lesions, precancerous lesions such as leukoplakias or erythroplakias and chronic ulcerations of unknown cause. It is also indicated for the histological confirmation of certain systemic disorders (Fig.1) and is recommended for apparently inflammatory lesions that do not improve within two weeks of removal of local irritants.

Other lesions that should also be biopsed include:

• lesions that interfere with oral function, such as fibrous hyperplasias and osseous lumps.

• lesions of unclear aetiology, particularly when associated with pain, paraesthesia or anaesthesia

• interstitial lesions in lingual, buccal or labial muscles

• radiolucent or radio-opaque osseous lesions.



When is oral biopsy not needed?

• There is no need to biopsy normal structures

• There is no need to biopsy irritative/traumatic lesions that respond to the removal of a presumed local irritant

• There is no need to biopsy inflammatory or infectious lesions that respond to specific local treatments, as pericoronitis, gingivitis or periodontal abscesses

• No incisional biopsies should be performed on suspected angiomatous lesions.



Types of biopsy

According to the procedures applied, oral biopsies can be classified by:

a) Features of the lesion:

• direct biopsy: when the lesion is located on the oral mucosa and can be easily accessed with a scalpel from the mucosal surface.

• indirect biopsy: when the lesion is covered by an apparently normal oral mucosa

b) Area of surgical removal:

• incisional biopsy: consists of the removal of a representative sample of the lesion and normal adjacent tissue in order to make a definitive diagnosis before treatment.

• excisional biopsy: is aimed at the complete surgical removal of the lesion for diagnostic and therapeutic purposes. This procedure is elective when the size and location of the lesion allows for a complete removal of the lesion and a wide margin of surrounding healthy tissue (Fig.2).

c) By the timing of the biopsy:

• Pre-operative

• Intra-operative

• Post-operative when aimed at checking the efficiency of a treatment.



General principles of oral biopsy

Before the procedure is undertaken, the characteristics of the lesion (size, shape, colour, texture, consistency, time of evolution, associated signs and symptoms, regional nodes) should be described in the patient’s clinical records together with a presumed diagnosis and possible differential diagnosis.

The patient should receive information on the technique that will be performed and the reasons why it is performed, avoiding terms that may cause anxiety. Informed consent is required.

Regarding the surgical technique:

• Regional block local analgesia rather than infiltrative techniques is preferred;

• elliptical incisions should be attempted in order to ease suture;

• incisions parallel to nerves and vases are preferred;

• if the lesion is smaller than 1 cm, excisional biopsy should be performed. If larger, an incisional technique including representative areas of the lesion with healthy margins should be chosen;

• when a malignant lesion is suspected, incisional technique is mandatory.

Samples must be oriented with a suture or a piece of paper, and introduced in a container with a fixing solution (10% formalin) (Fig.3)

The number and location of the biopsies will be decided on the basis of the clinical appearance of the lesion. If a lesion shows several areas where biopsy would be indicated, more than one sample should be taken. In these cases with precancerous or suspicious lesions, toluidine blue staining could be useful to choose the areas most relevant to biopsy.

The biopsy should be large enough to include normal and suspicious tissue and for the pathologist to give a diagnosis without further specimens (small samples are difficult to orientate and handle and certain processes as sample fixation may end in a reduction of the size of the specimen).

There are different procedures for undertaking oral biopsies. However, the selection of both technique and surgical instruments to use to avoid artefacts is controversial. The use of CO2 laser for the procurement of diagnostic biopsy specimens is compromised by thermal cytological artefacts. Problems of this nature are also witnessed with electrocautery. Punch biopsy has been suggested to reduce artefacts (Fig.4), although this has not been confirmed under controlled experimental conditions. Punch biopsy may tear the tissue in vesiculobullous conditions. Scalpel biopsy is the most widely accepted technique and the one that shows fewer limitations for obtaining samples from the oral cavity.



Scalpel technique for biopsy taking

In order to obtain good visibility, good illumination is needed. A Farabeuf-type separator or similar instrument to retract the lips and cheeks, and moderate-volume surgical aspiration are required.

The instruments suggested are:

- Cartridge-type local anaesthetic syringe

- Fine, single use, two-sided needles

- Cartridges of local anaesthetic solution

- Small and short scalpel blades (no. 15, 11, 12 or even 5)

- Mosquito forceps

- Allis tweezers

- 2/0 to 5/0 non-traumatic suture material

- Gauze

- Container with fixing solution

A biopsy technique can be reduced to six steps: selection of the area to biopsy, preparation of the surgical field, local anaesthesia, incision, handling of the specimen and suture of the resulting wound.

1. Selection of the area to biopsy

When dealing with small-sized lesion, an excisional biopsy will be performed, whereas incisional biopsy performed in the most representative area of the lesion is used for large lesions (long axis larger than 1 cm). If there is any doubt about the malignant character of the lesion, vital staining with toluidine blue can be use as an adjunct to select representative areas (Fig.5). Toluidine blue is a basic dye that fixes to nucleic acids and stains the nuclear content of malignant cells; in these cases samples should be taken from areas with deep blue patches, as light blue areas are not significant. Toluidine blue is used in three steps:

• wash the area with 1% acetic acid

• apply a 1% toluidine blue water solution for 1 minute

• mouthwash with 1% acetic acid

The sample must include healthy tissue at the margin of the lesion.

2. Preparation of the surgical field

The surgical area is disinfected with a quaternary ammonium compound. Iodine-containing surface antiseptics should not be used, as they may stain the tissues. A 0.12- 0.20 % chlorhexidine solution is preferred.

3. Local anaesthesia

An amide-type local anaesthetic with vasoconstrictor should be used and infiltrated away from the lesion are to avoid introducing artefacts in the sample.

4. The incision

Oral tissues should be immobilized far from the area to biopsy with non-toothed tweezers. A clean and defined incision is performed to obtain a slice of tissue when aiming at incisional biopsy. Soft tissues incisions should be elliptical in shape producing a “V” wedge that includes both the lesion and healthy margins. If various lesions are present, multiple biopsies should be taken.

5. Tissue handling

The specimen is handled gently to avoid crush artefacts and introduced in the fixing solution. The role of the fixing agent is to preserve the cellular architecture of the tissues. There are authors that suggest the placement of the specimen on a sterile paper with the mucous surface facing upwards to avoid distortion and curling of the sample margins.

The best fixing agent is a 10% formalin solution, as it induces less ultrastructural alterations in the samples. 70% ethanol can also be used. The samples should never be put in isopropyl or methyl alcohol, saline or distilled water - as severe alterations may be provoked.

The volume of the fixing agent should exceed 10 to 20-fold the volume of the sample.

When immunofluorescence or immunostaining are needed, specimens should not be fixed, but sent as soon as possible to the laboratory for freezing or put in Michel’s solution.

When the material is sent to the pathologist, it should be accompanied with a detailed report that includes identification of the patient, clinical records, clinical signs and a probable diagnosis as well as the orientation of the sample. An explanatory diagram of the biopsy area may be useful for this purpose.

6. Suture

The suture should achieve good haemostasis, facilitate healing and should be removed after 6-8 days.



What are the most frequent errors that should be avoided when taking oral biopsies?

In order to obtain a quality, artefact-free oral biopsy that permits the pathologist establish a histological diagnosis, the clinician should avoid:

• pressing the sample with the tweezers, particularly if toothed, as may produce tissue tears and “pseudomicrocysts”

• infiltrating anaesthetic solution within the lesion, as it can cause sample alterations

• applying products to the lesion that induce tissue modifications

• using an insufficient volume of fixing solution

• inclusion of undesired material in the sample: glove powder, calculus, restorative materials, etc.

• taking insufficient amount of tissue in extension and depth.