# Taurodontism--Prevalence, Extent, and Clinical Challenge in Ashkelon, Israel--A Retrospective Study
## 4 Discussion  
Taurodontism, which is defined as the enlargement of the pulp cavity of a molar tooth at the expense of root length [25], was investigated amongst Israelis in one medical center. The overall prevalence of tautodontism was 11.5% of all the molars examined and 33.6% of all patients. The reported prevalence of tautodon molars in the literature ranges widely. Lower prevalence of tautodontism in normal communities were reported in Germans (2%) [26], earlier (1978) in Israelis (6%) [9], moderately higher in Turks (11%) [27] and Iranians (23%) [7], with the highest reported in Brazilian (43%) [28] and Chinese (44%) [29] communities. These differences in prevalence rates reported in the literature is attributed not only to racial and ethnic differences, but also to the studies' methodology [7]. The criteria for the diagnosis of tautodontism in some studies are not comparable, as subjective diagnosis is combined with an objective analysis of the cases presented. Moreover, the wide range in prevalence in some reports was discovered using the same [PERSON] and [PERSON]'s methodology modified for panoramic radiographs, as performed in the current study, can be ascribed to a focus on mandibular molars, [29] as well as exclusion of third molars or inclusion of premolars [10]. The differences in the frequency of tautodontism in the Israeli population between current research and the 1978 research [9] may be due to several factors. First-possible differences may be derived from the differing methods of measurements of x-ray radiographs used. Originally, a full mouth periapical and posterior bitewing radiographs were used compared to panoramic radiographs in the current study. The age group assessed by [PERSON] and [PERSON] (1978) was between 20-30 years of age. By contrast, this study included patients between the ages 9 and 29. Including 9 years of age and above may theoretically have led to the undervaluation of the Variable 2 (T2), which is the distance between the lowest point of the roof of the pulp chamber to the apex of the longest root, due to incomplete root development in multiple molars, which is characteristic of that cohort [14,22]. However, it should be noted that these abovementioned uncompleted roots were excluded in the current study, and all the data presented relates to completed roots only. Therefore, the age differences of these two Israeli studies are not considered a contributing or causative variable. A second factor is the inclusion of the third molars (in the 1978 research) with a very low frequency of tautodontism can lead to different understandings and findings. In general, some of the studies reporting tautodontism reported only meso- and hypertaurodontism, ignoring hypotaurodontism. [22] Finally, the variability of sample size differs. The smaller the sample size, the more unrealistic the prevalence rate. Controversy exists regarding the role of gender in the occurrence of tautodontism [7]. In the current study, tautodontism was more prevalent in females (52% vs. 48%), but no statistical significance was detected. Literature demonstrates controversy on this issue. This higher prevalence in females is somehow expected since tautodontism may be related to the X chromosome [7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30] and corresponds to a study carried out in China (56% in females in comparison to 44% in males) [31]. However, others have reported an equal distribution between males and females [7,25,28,32,33]. In the present study, the teeth most affected by tautodontism were the maxillary molars (57% vs. 43%).