Evaluation of Third Molar Impaction Distribution and Patterns in a Sample of Lebanese Population.

BACKGROUND

Classifications of impaction based on panoramic radiographs such as the ones of Pell and Gregory and Winter are essential to allow a better understanding of third molar position regarding depth and bone coverage of the impacted tooth and to evaluate the difficulties of the surgical procedures. The aim of the study was to classify upper and lower third molars teeth in a sample of a Lebanese population and compare the data to results from other studies.

MATERIALS AND METHODS

Digital panoramic radiographs of 71 patients with a total of 181 wisdom teeth from patients that had been subjected for third molars extraction, from November 2016 to November 2018, were collected and analyzed. The mean age was 26.25 years. All third molars were categorized according to Pell and Gregory by using A, B, C scores for depth in upper and lower third molars, and angulations were classified according to Winter's classification. Nonparametric normality tests evaluating age group and gender distribution were conducted by utilizing the Chi-square test for age distribution and the binomial and Kruskal-Wallis tests for gender.

RESULTS

In the Pell and Gregory classification, the lower third molars showed type B impaction as the most frequent with 66.1% for the right side and 60.3% for the left side; the maxillary third molars both showed the type C impaction as the most frequent with 63.3% for the right side and 59.2% for the left side. According to the Winter classification, lower third molars showed mesio-angulation as the most frequent angle of impaction with 41.1% for right mandibular side and 46.5% for mandibular left side; As for the maxillary third molars, the disto-angulation was the most frequent angulation seen in both maxillary right and left side teeth 53.3% and 43.2%.

CONCLUSIONS

Comparison of our results with other populations has shown similarities in certain criteria like angulation and relation to ramus, but most results varied. Thus, the current study can be taken as a baseline for further studies.