A comparative study on radiographic analysis of impacted third molars among three ethnic groups of patients attending AIMST Dental Institute, Malaysia

Abstract

Background: The patterns of facial growth, jaw and tooth size are inherited and are likely to differ among population and races. Aim of this study is to evaluate and compare the pattern of third molar (3M) impaction among three different ethnic groups (Chinese, Indian, Malay) of patients attending AIMST Dental Institute, Malaysia.

Materials and Methods: Dental records and orthopantomographs of 2200 patients aged between 20 and 40 years were retrieved and examined retrospectively. Wherever impacted 3Ms were present, the status of 3Ms, their location, the level of impaction and angulations were recorded and analyzed using STATDISK (version 10.4) and the values obtained were compared with least square distance of 0.05 level.

Results: About 667 radiographs met with the inclusion criteria and showed the presence of 1008 impacted 3Ms. On overall comparison the incidence of level B impactions were found to be higher in our study. Level A impactions were frequently seen in Chinese (41.9%), level B in Indian (36.4%) and level C impactions had an equal distribution among Chinese and Malays (34.1%). The difference was highly significant (P ≥ 0.05). Mesioangular impaction (49.8%) followed by distoangular (22.9%) were the most common impactions among all the three races.

Conclusion: On comparison, mesioangular impaction was found to be the most frequent among all the three races whereas differences were seen in levels of impaction to some extent among theethnic groups. But as a limitation, our findings and results reflected the status of 3Ms of patients attending AIMST Dental Institute, not entire Malaysia. Therefore more similar studies have to be carried out in other parts of Malaysia to substantiate our present findings.

Key Words: Impaction, racial study, radiography, third molar