Genetic Analyses of Enamel Hypoplasia in Multiethnic Cohorts.

Enamel hypoplasia causes reduction in the thickness of affected enamel and is one of the most common dental anomalies. This defect is caused by environmental and/or genetic factors that interfere with tooth formation, emphasizing the importance of investigating enamel hypoplasia on an epidemiological and genetic level. A genome-wide association of enamel hypoplasia was performed in multiple cohorts, overall comprising 7,159 individuals ranging in age from 7-82 years. Mixed-models were used to test for genetic association while simultaneously accounting for relatedness and genetic population structure. Meta-analysis was then performed. More than 5 million single-nucleotide polymorphisms were tested in individual cohorts. Analyses of the individual cohorts and meta-analysis identified association signals close to genome-wide significance (P < 510-8), and many suggestive association signals (510-8 < P < 510-6) near genes with plausible roles in tooth/enamel development. The strongest association signal (P = 1.5710-9) was observed near BMP2K in one of the individual cohorts. Additional suggestive signals were observed near genes with plausible roles in tooth development in the meta-analysis, such as SLC4A4 which can influence enamel hypoplasia. Additional human genetic studies are needed to replicate these results and functional studies in model systems are needed to validate our findings.

Genome-Wide Association Study (GWAS) of dental caries in diverse populations.

BACKGROUND: Dental caries is one of the most common chronic diseases and is influenced by a complex interplay of genetic and environmental factors. Most previous genetic studies of caries have focused on identifying genes that contribute to dental caries in specific ethnic groups, usually of European descent. METHODS: The aim of this study is to conduct a genome-wide association study (GWAS) to identify associations affecting susceptibility to caries in a large multiethnic population from Argentina, the Philippines, Guatemala, Hungary, and the USA, originally recruited for studies of orofacial clefts (POFC, N = 3686). Ages of the participants ranged from 2 to 12 years for analysis of the primary dentition, and 18-60 years for analysis of the permanent dentition. For each participant, dental caries was assessed by counts of decayed and filled teeth (dft/DFT) and genetic variants (single nucleotide polymorphisms, SNPs) were genotyped or imputed across the entire genome. Caries was analyzed separately for the primary and permanent dentitions, with age, gender, and presence/absence of any type of OFC treated as covariates. Efficient Mixed-Model Association eXpedited (EMMAX) was used to test genetic association, while simultaneously accounting for relatedness and stratification. RESULTS: We identified several suggestive loci (5 × 10-8 < P < 5 × 10-6) within or near genes with plausible biological roles for dental caries, including a cluster of taste receptor genes (TAS2R38, TAS2R3, TAS2R4, TASR25) on chromosome 7 for the permanent dentition analysis, and DLX3 and DLX4 on chromosome 17 for the primary dentition analysis. Genome-wide significant results were seen with SNPs in the primary dentition only; however, none of the identified genes near these variants have known roles in cariogenesis. CONCLUSION: The results of this study warrant further investigation and may lead to a better understanding of cariogenesis in diverse populations, and help to improve dental caries prediction, prevention, and/or treatment in future.

Survey investigation of articaine use in the United States.

BACKGROUND: Local anesthesia is an essential component of dentistry, but there is limited quantifiable understanding of what techniques and local anesthetic solutions are used by practicing dentists. Use of the local anesthetic articaine has been highly debated in dentistry regarding its efficacy and risks for paresthesia. The aims of this study were to expand the knowledge of local anesthesia practices of dentists in the United States through a large-scale survey and associate potential influencing factors regarding articaine use specifically. METHODS: The 23-item survey was sent to 10,340 practicing dentists in the United States, gathering demographic data and local anesthesia approaches and concerns. Statistical analysis consisted of descriptive, bivariate, and multivariate logistic regression analyses. RESULTS: A total of 1,128 dentists completed the survey. Previous experience with articaine was reported by 97.6% of respondents, with 3.3% no longer using articaine. Sixty percent of respondents indicated using articaine for most local anesthetic injections administered. Multivariable regression analysis found those reporting to use articaine for all local anesthetic injections involving vasoconstrictors were more likely to be male (odds ratio, 1.59; P = .002) or general dentists (odds ratio, 1.63; P < .001). CONCLUSIONS: Articaine has a perceived benefit to practitioners as most respondents reported using articaine as their primary local anesthetic. A practitioner's sex and type were found to affect the profile of use of articaine. PRACTICAL IMPLICATIONS: Assembling evidenced-based local anesthesia practices would be beneficial to ensure US practitioners are more standardized in administering local anesthetics, particularly articaine, in the safest and most efficacious way.

Exploring dental faculty perceptions of current strategies and barriers to retention.

PURPOSE: The aims of the study were to identify perceived strategies for and barriers to faculty retention and examine differences regarding age, gender, and race. METHODS: Cross-sectional data was captured from the eight author-affiliated dental schools. A Qualtrics survey was emailed to all faculty members at these institutions (1467 possible participants) between November 2021 and February 2022. The survey was formulated from best practices listed in the American Dental Education Association Faculty Diversity Toolkit. It consisted of 18 questions, including demographic information and faculty perceptions of their respective workplaces. These responses were then evaluated with descriptive statistics, Chi-squared analysis, Pearson Correlation, and Fleiss' kappa. RESULTS: The survey's response rate was 19.2%. There was no significant difference in perceived retention strategies across race, age, gender, practice tenure, practice type, or clinical versus tenure track. The top four barriers identified were inadequate financial compensation, workload, poor work environment, and burnout. There was a significant difference between racial groups and their perceived barrier of support for promotion (p = 0.048). This was more prevalent among clinical faculty (47.7%) than tenure track faculty (16.2%). The work environment was listed as a leading factor for both promoting retention and encouraging the exodus of faculty members. CONCLUSION: Strategies aimed at improving financial compensation, career recognition, and transparency of the promotion process, along with those aimed at improving the work environment were shown to be vital to retaining faculty. Though the low response rate is a study limitation, these findings provide valuable information and a framework for future studies regarding dental faculty recruitment and retention.

BigMouth: development and maintenance of a successful dental data repository.

Few clinical datasets exist in dentistry to conduct secondary research. Hence, a novel dental data repository called BigMouth was developed, which has grown to include 11 academic institutions contributing Electronic Health Record data on over 4.5 million patients. The primary purpose for BigMouth is to serve as a high-quality resource for rapidly conducting oral health-related research. BigMouth allows for assessing the oral health status of a diverse US patient population; provides rationale and evidence for new oral health care delivery modes; and embraces the specific oral health research education mission. A data governance framework that encouraged data sharing while controlling contributed data was initially developed. This transformed over time into a mature framework, including a fee schedule for data requests and allowing access to researchers from noncontributing institutions. Adoption of BigMouth helps to foster new collaborations between clinical, epidemiological, statistical, and informatics experts and provides an additional venue for professional development.

Dental anomaly detection using intraoral photos via deep learning.

Children with orofacial clefting (OFC) present with a wide range of dental anomalies. Identifying these anomalies is vital to understand their etiology and to discern the complex phenotypic spectrum of OFC. Such anomalies are currently identified using intra-oral exams by dentists, a costly and time-consuming process. We claim that automating the process of anomaly detection using deep neural networks (DNNs) could increase efficiency and provide reliable anomaly detection while potentially increasing the speed of research discovery. This study characterizes the use of` DNNs to identify dental anomalies by training a DNN model using intraoral photographs from the largest international cohort to date of children with nonsyndromic OFC and controls (OFC1). In this project, the intraoral images were submitted to a Convolutional Neural Network model to perform multi-label multi-class classification of 10 dental anomalies. The network predicts whether an individual exhibits any of the 10 anomalies and can do so significantly faster than a human rater can. For all but three anomalies, F1 scores suggest that our model performs competitively at anomaly detection when compared to a dentist with 8 years of clinical experience. In addition, we use saliency maps to provide a post-hoc interpretation for our model's predictions. This enables dentists to examine and verify our model's predictions.

Tooth Agenesis Patterns in Orofacial Clefting Using Tooth Agenesis Code: A Meta-Analysis.

Individuals with orofacial clefting (OFC) have a higher prevalence of tooth agenesis (TA) overall. Neither the precise etiology of TA, nor whether TA occurs in patterns that differ by gender or cleft type is yet known. This meta-analysis aims to identify the spectrum of tooth agenesis patterns in subjects with non-syndromic OFC and controls using the Tooth Agenesis Code (TAC) program. An indexed search of databases (PubMed, EMBASE, and CINAHL) along with cross-referencing and hand searches were completed from May to June 2019 and re-run in February 2022. Additionally, unpublished TAC data from 914 individuals with OFC and 932 controls were included. TAC pattern frequencies per study were analyzed using a random effects meta-analysis model. A thorough review of 45 records retrieved resulted in 4 articles meeting eligibility criteria, comprising 2182 subjects with OFC and 3171 controls. No TA (0.0.0.0) was seen in 51% of OFC cases and 97% of controls. TAC patterns 0.2.0.0, 2.0.0.0, and 2.2.0.0 indicating uni- or bi-lateral missing upper laterals, and 16.0.0.0 indicating missing upper right second premolar, were more common in subjects with OFC. Subjects with OFC have unique TA patterns and defining these patterns will help increase our understanding of the complex etiology underlying TA.

Multivariate GWAS of Structural Dental Anomalies and Dental Caries in a Multi-Ethnic Cohort.

Odontogenesis is a complex process, where disruption can result in dental anomalies and/or increase the risk of developing dental caries. Based on previous studies, certain dental anomalies tend to co-occur in patients, suggesting that these traits may share common genetic and etiological components. The main goal of this study was to implement a multivariate genome-wide association study approach to identify genetic variants shared between correlated structural dental anomalies and dental caries. Our cohort (N = 3,579) was derived from the Pittsburgh Orofacial Clefts Study, where multiple dental traits were assessed in both the unaffected relatives of orofacial cleft (OFC) cases (n = 2,187) and unaffected controls (n = 1,392). We identified four multivariate patterns of correlated traits in this data: tooth agenesis, impaction, and rotation (AIR); enamel hypoplasia, displacement, and rotation (HDR); displacement, rotation, and mamelon (DRM); and dental caries, tooth agenesis and enamel hypoplasia (CAH). We analyzed each of these four models using genome-wide multivariate tests of association. No genome-wide statistically significant results were found, but we identified multiple suggestive association signals (P < 10-5) near genes with known biological roles during tooth development, including ADAMTS9 and PRICKLE2 associated with AIR; GLIS3, WDR72, and ROR2 associated with HDR and DRM; ROBO2 associated with DRM; BMP7 associated with HDR; and ROBO1, SMAD2, and MSX2 associated with CAH. This is the first study to investigate genetic associations for multivariate patterns of correlated dental anomalies and dental caries. Further studies are needed to replicate these results in independent cohorts.

Retention and recruitment of general dentists in an adjunct teaching model-A pilot study.

PURPOSE/OBJECTIVES: Retention and recruitment of part time clinical adjunct faculty members in dental education is becoming increasingly difficult as dental schools come to rely on this workforce for their increased involvement in clinical education. Contributing factors include full time faculty shortage, aging workforce, practice and student debt, practice and family commitments, and financial compensation. This study attempts to ascertain barriers to teaching so appropriate strategies can be formulated to address this issue. METHODS: In the spring of 2016 an email survey was sent to current and former adjunct faculty members to ascertain demographics and retention and recruitment strategies. Descriptive analyses were completed for all variables in the sample. RESULTS: Twenty nine of forty six subjects responded to the survey with a response rate of 63%. Subjects over the age of sixty comprised 55% with only 17% being under the age of forty five. Overall family and practice commitments along with compensation were the primary barriers to teaching part time. For new dentists, student loan debt was the primary barrier to teaching. Travel to teach was also a barrier as 70% of respondents drove 200 miles or less to the dental school. CONCLUSION: The study demonstrated that the aging part time work force is a great concern and new part time clinical adjunct faculty members must be recruited. Barriers to recruitment and retention of faculty must be considered and addressed to sustain this teaching model.