M. P.

Do dentist collect data on anormalities for statistics like cancer found nationwide or provincial or state

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

Unfortunately, dentists do not collect this type of epidemiological data for abnormalities seen in their practices. But it would be great if they did! As for cancer, I believe that hospitals do collect incidence data because this is reported yearly in Canada through the Canadian Cancer Society and in the US by the National Cancer Institute.

F. A.

what was the etiology of rarefying osteitis associated with amelogenesis imperfecta ?

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

In hypoplastic amelogenesis imperfecta, the enamel is relatively thin, so if caries develops in the crown, it may track more quickly through the tooth because the enamel is thinner. When this happens, it is possible that the caries arrives at the coronal pulp more quickly than if the layer of enamel was of normal thickness. Then the usual progression of pulpal necrosis is initiated, resulting in the area of periapical rarefying osteitis.

K. V.

This presentation was excellent. When you show the first pano with cancer I saw a radio opacity on top the milohiod canal. and another that suggest phlebolits. Those where associated to the SSC?

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

Those were tonsilloliths. They are not associated with squamous cell carcinoma; they were an incidental finding.

J. C.

Why do you refer to it as odontom rather than odontoma

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

I refer to this entity as an odontome and not an odontoma. That is because the suffix "-oma" is used to describe a benign neoplasm or tumour. I see odontomes as hamartomas, so have moved away from odontoma in favour of odontome.

Mrs. Amanda McDonald

Can healing lesions become/change into a problematic lesion? If so, an example?

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

No. A healing defect will just fill as much as it can with bone; it will not be problematic.

Mrs. Amanda McDonald

Can healing lesions become/change into a problematic lesion? If so, an example?

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

No. A healing defect will just fill as much as it can with bone; it will not be problematic.

Dr. Francisco Otero

Great presentation Dr. Lam. Do you request a complete as possible clinical information before or after you obtain the radiographic images in order to establish an accurate diagnosis?

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

There are times when radiology may not be the definitive diagnostic test. I have a sense as to when imaging is definitive and when it is not, and this comes from an understanding of the limitations of imaging. So in instances where the imaging features do not allow my opinion to be definitive, I will suggests additional tests to aid in the diagnosis.

Ms. Najja Rannie

When it comes to root canaled teeth, there has been some patient complaints online due to the material used and adverse health effects. What are your thoughts?

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

These are anecdotal reports and lack any scientific validity.

Dr. Bryon Roshong

Does the location of the closeness to the inferior alveolar canal cause the appearance of a more significant radiolucency J Endo radiographs?

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

No. The appearance of an increasingly evident radiolucent appearance, particularly in the mandible, has to do with the increasing size of the rarefying ostieits impinging on the inside surface of the cortex (either buccal or lingual). As the cortical bone becomes thinner, the radiolucency becomes more evident. These are the references: Bender IB, Seltzer S. Roentgenographic and direct observation of experimental lesions in bone: I. J Am Dent Assoc 1961;62:152–60. Bender IB. Factors influencing the radiographic appearance of bone lesions. J Endod1982;8:161–70.

Laila Bonner

is dens invaginatus always found in canals or can they also be found in pulp chambers like pulp stones, thanks

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

Dens invaginatus is a condition where there is an extension of the foramen caecum located adjacent to the cingulum of a maxillary incisor into the coronal portion of the pulp chamber; so it is not "found in the canal", per se. The issue is that bacteria can make its way into the invagination and because the area cannot be cleaned, caries develops at the base of the invagination leading to pulpal necrosis and rarefying osteitis. I do not believe there is an association between dens invaginatus and the development of pulp stones.

Dr. richard titlebaum

Is there any cause for concern or treatment for a cemento-osseous dysplastic lesion that perforated the cortical plate?

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

No, not unless the patient reports pain from an area of cemento-osseous dysplasia. If there is pain, it usually means the site has become secondarily-inflamed due to exposure to oral bacteria.

Ms. Carmen Pena

How do you identify the epicentre??

Ernest Lam DMD, MSc, PhD, FRCD(C) Associate Dean, Graduate Education University of Toronto

Epicenter is defined as being the intercept between two (or 3) lines that define the widest mesial/distal and superior/inferior (and medial/lateral) dimensions of an abnormality.