Dental anomalies occur frequently in a number of genetic disorders and act as major signs in diagnosing these disorders. We present definitions of the most common dental signs and propose a classification usable as a diagnostic tool by dentists, clinical geneticists, and other health care providers. The definitions are part of the series Elements of Morphology and have been established after careful discussions within an international group of experienced dentists and geneticists. The classification system was elaborated in the French collaborative network “TÊTECOU” and the affiliated O‐Rares reference/competence centers. The classification includes isolated and syndromic disorders with oral and dental anomalies, to which causative genes and main extraoral signs and symptoms are added. A systematic literature analysis yielded 408 entities of which a causal gene has been identified in 79%. We classified dental disorders in eight groups: dental agenesis, supernumerary teeth, dental size and/or shape, enamel, dentin, dental eruption, periodontal and gingival, and tumor‐like anomalies. We aim the classification to act as a shared reference for clinical and epidemiological studies. We welcome critical evaluations of the definitions and classification and will regularly update the classification for newly recognized conditions.

The most common outcome of defective dental morphogenesis in human patients is dental agenesis (absence of teeth). This may affect either the primary or permanent dentition and can range from 5 or fewer missing teeth (hypodontia), 6 or more (oligodontia), to complete absence of teeth (anodontia). Both isolated and syndromic dental agenesis have been reported to be associated with a large number of mutated genes. The aim of this review was to analyze the dental phenotypes of syndromic and nonsyndromic dental agenesis linked to gene mutations. A systematic review of the literature focusing on genes (MSX1, PAX9, AXIN2, PITX2, WNT10A, NEMO, EDA, EDAR, EDARADD, GREMLIN2, LTBP3, LRP6, and SMOC2) known to be involved in dental agenesis was performed and included 101 articles. A meta-analysis was performed using the dental phenotypes of 522 patients. The total number and type of missing teeth were analyzed for each mutated gene. The percentages of missing teeth for each gene were compared to determine correlations between genotypes and phenotypes. Third molar agenesis was included in the clinical phenotype assessment. The findings show that isolated dental agenesis exists as part of a spectrum of syndromes for all the identified genes except PAX9 and that the pattern of dental agenesis can be useful in clinical diagnosis to identify (or narrow) the causative gene mutations. While third molar agenesis was the most frequent type of dental agenesis, affecting 70% of patients, it was described in only 30% of patients with EDA gene mutations. This study shows that the pattern of dental agenesis gives information about the mutated gene and could guide molecular diagnosis for geneticists.

Background: The purpose of the present study was to evaluate the esthetic outcome using four categories of root‐coverage procedures (pedicle soft tissue grafts, non‐submerged grafts, submerged grafts, and envelope techniques) and to identify factors associated with esthetic assessment.Methods: A professional panel of three observers (two periodontists and one control) used a before–after panel scoring system to evaluate the esthetics of 162 root‐coverage surgeries. A five‐point ordinal scale was used to evaluate the overall esthetic improvement and seven variables that may be considered in the assessment.Results: The intraobserver agreement of the two trained periodontists for the overall cosmetic assessment was almost perfect (κ = 0.83), and substantial agreement was found between them (κ = 0.68). Good to excellent overall esthetic results were found by the professionals and control in >70% of the surgical procedures. Analysis of variance indicated a statistical difference between the non‐submerged grafts category and the three other surgical categories (P <10⁻³). Multivariate analysis showed that the degree of root coverage was not a significant predictive factor, whereas soft tissue appearance variables and the follow‐up were significantly associated with cosmetic assessment.Conclusions: The present study demonstrated that non‐submerged grafts are not recommended in cases of esthetic demand. Future root‐coverage trials, basing their justification on esthetics, should include overall qualitative evaluation as the primary variable. The follow‐up period should not be <12 months. The before–after panel scoring system is a tool that can be used to evaluate cosmetic outcomes.