Research algorithm for the detection of genetic patterns and phenotypic variety of non-syndromic dental agenesis.

INTRODUCTION: Dental agenesis (DA), brings together the anodontia, oligodontia, hypodontia, characterized by a deficit in the development of a variable number of teeth. The objectives of the study were to illustrate the phenotypic variability of non-syndromic DA, to identify cases of DA with hereditary genetic transmission, and establish the mode of DA genetic pattern in these cases, together with the determination of DA prevalence in the population group study. PATIENTS, MATERIALS AND METHODS: The cross-sectional observational study was performed on a mixed population group, consisting of 861 Caucasian patients, between January 2018-December 2019. The clinical evaluation protocol of patients with DA, used to illustrate their phenotype, included the following stages: oral examination, photographic examination, and radiological examination. The evaluation protocol specific to the family genetic study of patients with DA, involved the following three stages: family survey, construction of the family tree and analysis of the pedigree structure. RESULTS: The prevalence of DA in the population group was 2.78%. Regarding the phenotype, DA mainly affected the upper arch (50% of cases); bilateral DA had a significantly increased incidence (83.33% of cases) compared to unilateral form; in most cases (75%), a patient lacked one to two teeth, the lack of two teeth being the most common form (83.33% of cases); the upper lateral incisors were the teeth most frequently involved in DA (31.11% of the total missing teeth). Regarding the family genetic study, hereditary DA with autosomal dominant inheritance was present in 37.50% of cases. In the other cases (62.50%), isolated, sporadic forms of DA were registered, suggesting a spontaneous de novo mutation or a disorder of odontogenesis of a non-genetic nature. CONCLUSIONS: We consider that this study is of interest for current scientific research with applicability in dental medicine, by bringing actual information on the prevalence of non-syndromic DA in South-East Romania, the variety of phenotypic spectrum of DA for this geographic area, and the role of heredity in the DA genetic determinism in the studied population.

Phenotypic heterogeneity of non-syndromic supernumerary teeth: genetic study.

BACKGROUND: Numerical dental anomalies, through their phenotypic diversity and etiological complexity, represent a very topical chapter in dental practice. In Romania, there is no recent complex genetic study, regarding supernumerary teeth (ST), as a whole. PATIENTS, MATERIALS AND METHODS: In this research, through the specific genetic study of the phenotypic variability of ST, completed with clinical examinations and paraclinical investigations, to which statistical determinations were added, we performed a complex genetic-clinical and statistical analysis of ST, within a representative group, consisting of 574 patients, who came for specialized dental treatment, between 01/01/2018-05/30/2019, at the private dental offices (Lucky Dental), in Bucharest, Romania. RESULTS: Following this study, it was possible to characterize the phenotypic variability of ST, to analyze the pattern of abnormality genetic transmission in the families of investigated patients, to identify people at risk, and specify the therapeutic conduct of choice, specific to each case. CONCLUSIONS: We consider this paper to be of interest for medical practice by bringing new, recent data on the current prevalence of non-syndromic ST, their clinical phenotypes, and the specifics of their genetic determinism in the studied population group.