Mesial roots of first and second molars mostly had one large canal until 11 and 15 years of age, respectively. In both molars, the canal system was completely defined at 30-40 years. The prevalence of inter-canal communications was low at young and old ages but high at intermediate ages.

BackgroundThe main objective of this study was to describe selected clinico-pathological characteristics of Oral Squamous Cell Carcinoma (OSCC) in Sri-Lanka.Materials & methodsThe study sample comprised of eight hundred and ninety six biopsies diagnosed as OSCC. The clinical and histopathological features were analyzed using the Chi-square test.ResultsOf the 896 biopsies, 801 were primary OSCCs, while 95 were recurrent OSCCs. Majority of the patients (78 %) were in the 5th to 7th decades of life and showed a male predilection. The buccal mucosa was the commonest site of primary OSCC comprising of 43 % of the sample. Of the primary OSCCs, with known TNM stage, 86 % were in stage 3&4 and majority (59 %) of stage 4 tumours showed tumour at one or more excision margins. Of the recurrent OSCC, 46 % developed their recurrences within one year of the excision of the primary tumour.ConclusionIn Sri-Lanka, OSCC is a major problem. Only half the patients had completely excised tumours (with clearance of >5 mm at all excision margins) at operation, and recurrences appeared early. This data should be considered in the future management policy of OSCC in Sri-Lanka.

Cutaneous dirofilariasis usually affects animals such as cats and dogs which are known to be the natural host of Dirofilaria. Dirofilariasis displays a worldwide distribution. Certain geographic regions account for the majority of reported cases. South-eastern United States, Australia and Europe have been identified as endemic regions (1, 2). However, new endemic areas are arising with increased awareness in African and Asian regions. Out of about 40 different species of Dirofilaria only a few species are commonly known to infect man, namely Dirofilaria immitus, D. tenices and D. repens. Human infection occurs when a human becomes a blood meal of an infected arthropod vector and on accidental entering of the worm. Rarely this zoonotic infection affects the oral mucosa (3). Man is the dead end of this parasite. Since the human body is an abnormal environment for the parasite, the development of the larvae is inhibited by means of retardation of sexual maturity. Lesions are presented as single non-tender subcutaneous nodules, and most patients are asymptomatic. Diagnosis is established by H&E sections prepared from excised nodules. In a majority of the cases, only a single worm either a male or a female could be identified. The worm is usually dead and degenerated with a massive inflammatory cell infiltration. Seven new cases presented as intra-oral nodules with their clinicopathological correlation are discussed.

Background Developing histological prediction models that estimate the probability of developing metastatic deposit will help clinicians to identify individuals who need either radical or prophylactic neck dissection, which leads to better prognosis. Identification of accurate predictive models in oral cancer is important to overcome extensive prophylactic surgical management for neck nodes. Therefore, accurate prediction of metastasis in oral cancer would have an immediate clinical impact, especially to avoid unnecessary radical treatment of patients who are at a low risk of metastasis. Methods Histologically confirmed OSCC cases with neck dissection were used. Interrelation of demographic, clinical, and histological data was done using univariate and multivariate analysis. Results 465 cases were used and presence of metastasis and extracapsular invasion were statistically well correlated with level of differentiation (p < 0.001) and pattern of invasion (p < 0.001). Multivariate analysis showed level of differentiation, pattern of invasion, and stage as predictors of metastasis. Conclusions The proposed predictive model may provide some guidance for maxillofacial surgeons to decide the appropriate treatment plan for OSCC, especially in developing countries. This model appears to be reliable and simple and may guide surgeons in planning surgical management of neck nodes.