Kanneppady Sham Kishor, Kumaresan Ramesh, Sakri Santosh B
Department of Oral Medicine and Radiology, Century International Institute of Dental Science and Research Centre, Poinachi, Kasaragod, Kerala, India.
Dent Res J (Isfahan). 2013 May;10(3):353-8.
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.
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.
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.
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 the ethnic 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.
面部生长模式、颌骨及牙齿大小是可遗传的,且在不同人群和种族中可能存在差异。本研究旨在评估和比较马来西亚艾姆斯牙科研究所中三个不同种族(华人、印度人、马来人)患者的第三磨牙(3M)阻生模式。
回顾性检索并检查了2200例年龄在20至40岁之间患者的牙科记录和曲面断层片。对于存在阻生3M的情况,记录3M的状态、位置、阻生水平和角度,并使用STATDISK(版本10.4)进行分析,所得值与0.05水平的最小二乘距离进行比较。
约667张X线片符合纳入标准,显示存在1008颗阻生3M。总体比较发现,本研究中B级阻生的发生率较高。A级阻生在华人中常见(41.9%),B级在印度人中常见(36.4%),C级阻生在华人和马来人中分布相同(34.1%)。差异具有高度显著性(P≥0.05)。近中阻生(49.8%)其次是远中阻生(22.9%)是所有三个种族中最常见的阻生类型。
比较发现,近中阻生在所有三个种族中最为常见,而不同种族在阻生水平上在一定程度上存在差异。但作为局限性,我们的研究结果反映的是在艾姆斯牙科研究所就诊患者的3M情况,而非整个马来西亚的情况。因此,必须在马来西亚其他地区开展更多类似研究以证实我们目前的发现。