Abstract
Squamous cell carcinoma of the tongue is the most common malignant lesion seen in the oral cavity. The lesion of the anterior two-third is usually predominant in cases of adults over 40 years of age, and the occurrence of similar carcinoma in younger adults is thought to be quite unusual.
As the etiological factors of the lesion, consumption of alcohol or tobacco, chronic irritation from jaggy teeth and dental appliance and many other things have been pointed out by many authors. But, none of these factors have been clearly identified in younger adults with the lesion.
The lesion predominantly occurs on the lateral border of the tongue having been stimulated by chronic mechanical irritation, so it is possidle that adjacent natural teeth and dental prostheses relate to its occurrence.
During the 10-years from 1978 to 1987, 65 younger adult patients with squamous cell carcinoma of lateral border of the tongue visited the department of Head and Neck Tumor, Cancer Institute Hospital. In many of them, it is suggestive that the chronic irritation from teeth may promote the occurrence of the lesion.
For this reason, we examined those patients particularly about the presence of poor dentition. Especially about the cases with no missing tooth on the affected side, taking impression of the lower dental arch and making plaster study models, we analysed abnormal lingual inclination and lingo-version of teeth using the models. So, in many of the cases, poor dentition could be found and we suspect that this factor might promte the early onset of squamous cell carcinoma on the lateral bordes of the tongue.
