Morphology of the endodont of mandibular molars in Buryat population

Of particular interest to clinicians is information about the accessory roots and canals of the mandibular molars, in particular the distolingual root, called Radix Entomolaris (RE) in the literature. A previous study suggested the influence of the brachycephalic type of skull of the Mongoloids (Buryats) on the incidence of RE. However, we did not find specific studies of such a connection in the available literature. The aim. To study the correlation between the frequency of occurrence of the RE root and the type of skull in different ethnic groups of the population based on cephalometric and cone beam computed tomography (CBCT) data of the skull. Materials and methods. During the initial examination of people who applied to the clinic, an experimental group of 186 people, representatives of the indigenous ethnic group of Transbaikalia, was identified and their CT scans of the skull were studied. A division into cephalometric groups (brachy-, meso-, dolichocephalic) was carried out, the frequency of detection of the RE root in each subgroup was assessed, and correlations between the type of skull and the frequency of occurrence of RE were assessed using the Statistica.10 statistical analysis software package (StatSoft, USA). Results. The analysis showed a very weak positive relationship between the distribution of RE and the type of skull in the studied ethnic group. The frequency of RE detection in Buryat ethnic groups is significantly higher than in Caucasians. A separate distolingual root of the first mandibular molar was detected in 9,7 % of cases (in the control – 0 %; χ²=6,87; p<0,05). There was no correlation between the frequency of RE detection and the type of skull in the experimental group (r=0,12; р>0,05), which allows us to consider the presence of this root in the studied ethnic group as an eumorphic (inherited) anatomical feature. Сonclusion. The frequency of RE detection in individuals of the Buryat ethnic group of Transbaikalia is 9,7 %, which is significantly higher than in Caucasians. The absence of a correlation between the frequency of RE detection and the type of skull allows us to consider the presence of this root in the Buryat ethnic group as an eumorphic (inherited) anatomical feature.

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