Novel dental phenotype in non-syndromic Pierre Robin Sequence: A retrospective study

The objective was to investigate dental phenotypes in individuals with non-syndromic Pierre Robin Sequence (ns-PRS) and compare the prevalence of these phenotypes with subjects with non-syndromic cleft palate (ns-CP) and a control group with subjects without any craniofacial anomalies.

A total of 760 panoramic radiographs of 330 individuals (110 with ns-PRS; 110 with ns-CP and 110 without any malformations) were digitized and evaluated regarding the diagnosis of taurodontism, tooth agenesis, root dilaceration and tooth transposition. Chi-square test was applied to compare the occurrence of dental phenotypes between groups. A P value of less than 0.05 was considered statistically significant.

Total prevalence of dental phenotypes was 94.5% of ns-PRS; 54.5% of ns-CP and 59.1% of the control group subjects with a statistically significant difference for the ns-PRS when compared to the other two groups. Two dental phenotypes, taurodontism and dental agenesis were identified with statistically significant higher prevalences in subjects with ns-PRS when compared with the ns-CP group and the control group (p < 0.001). Taurodontism was the most prevalent dental phenotype, with 92.73% in the ns-PRS group, 40.91% for ns-CP and 44.55% in the control group. Tooth agenesis had a prevalence of 22.7% for ns-PRS, 4.5% for ns-CP and no case in the control group. For the prevalence of root dilaceration and tooth transposition, no statistically significant differences were observed between the three groups.

Due to the high frequency of taurodontism in individuals with ns-PRS, we suggested that this novel phenotype would be important in the phenotypic screening of ns-PRS and could be considered as a phenotype associated with ns-PRS.