Objectives: Sexual dimorphism has been shown to influence disease predisposition and/or progression, however, studies addressing sex-based differences in dental, oral, and craniofacial (DOC) diseases and conditions are scarce. This study aimed to identify DOC diseases and conditions likely influenced by sexual dimorphism using two large data repositories. Methods: Retrospective study of medical/dental record data obtained from adult participants (>18 years old) in the NIH All of Us Research Program (n=254,700) and the BigMouth Data Repository (n ≈ 4.7 million). The number of males and females presenting each selected DOC disease concept in each database was recorded. Sex-specific association analysis for each concept was performed using chi-square tests (α ≦ 0.0002). Female-to-male odds ratio (OR) and confidence intervals were also calculated. Results: The initial search in All of Us and BigMouth yielded 216 and 243 DOC concepts, respectively. Eighty-seven of 216 dental concepts identified in All of Us had sex-stratified data. Of these, significant sex-related differences were found for 61/87 concepts (70%), with 33 concepts (54%) showing female bias and 28 (46%) showing male bias (P≦ 0.0002). Higher female bias was noted for diseases of oral soft tissues, disorders of tooth development and eruption, and diseases of pulpal/periapical tissues, whereas higher male bias was noted for gingival and periodontal diseases, dental caries, and malignant tumor of oral cavity (P≦ 0.0002). Analysis of BigMouth data showed sex bias for 90/230 (39%) concepts investigated, of which 87 (97%) showed female bias and 3 (3%) showed male bias (P≦ 0.0002). Discordant sex bias results among the databases were noted for 8 concepts. Conclusions: This study provides evidence of sex bias in numerous DOC diseases and conditions in the populations studied. Additional studies in other populations and considering sociodemographic factors might provide further insight into the role of sexual dimorphism in DOC diseases.

The authors have declared no competing interest.

This study was funded by a Dean's Summer Research Scholarship to Emma Fetchko.

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The study used ONLY openly available human data that were originally located at the All of Us Research Program Data Browser and the BigMouth data repository.

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