Human craniofacial morphology is a hallmark of our species' diversity and evolutionary history, shaped by adaptation, introgression, and global dispersal. Cranial globularization and chin emergence are well-documented morphological transformations whose genetic basis remains poorly understood, whereas Neandertal introgression is primarily documented through genomic evidence. How these evolutionary phenomena relate to craniofacial variation in present-day humans remains largely unresolved. Here, we leverage 3D craniofacial data from over 50,000 UK Biobank participants and employ a multivariate, multiscale genome-wide association approach to define axes of variation aligned with interpopulation allele frequency shifts, evolutionary processes, and clinical conditions. We identify continuous craniofacial trends within our cohort that mirror global patterns of genetic diversity, indicating that facial differences between human populations arise at the phenotypic axes already present within a single population. We further demonstrate that modern human-derived alleles underlie the origins of the human chin by reducing midfacial projection relative to other hominins and reveal the persistent effects of Neandertal introgression on craniofacial diversity today. We also model genetically informed endophenotypes for orofacial clefts, obstructive sleep apnoea, and myopia. These findings provide insights into our species' evolutionary history and endophenotypes of clinical conditions and establish a framework for contextualizing craniofacial diversity into biologically meaningful axes of variation relevant to diverse scientific disciplines.

Orofacial clefts (OFCs) are the most common craniofacial birth defect and comprise a diverse group of traits with complex and heterogeneous etiologies. Genetic studies of OFCs typically approach this diversity by stratifying cases into broad diagnostic classes, including cleft lip (CL), cleft palate (CP), and cleft lip with palate (CLP). Although this strategy has yielded important insights into OFC risk, it ignores the phenotypic heterogeneity within each subtype. CL exhibits marked phenotypic variability, involving differences in alveolar involvement, laterality, and sidedness that may reflect distinct etiologies. Given this phenotypic diversity within CL, we assembled a multi-ancestry cohort of 837 nonsyndromic CL case-parent trios with whole-genome sequencing and detailed phenotyping. We performed genome-wide association scans (GWAS) via transmission disequilibrium tests for CL overall and for 14 CL subtypes defined by involvement of the alveolus (with and without), laterality (uni- and bilateral), and sidedness (left and right). We identified four genome-wide significant loci. Two loci, IRF6 and 8q24.21, were both detected in the overall CL GWAS. PLCB1/PLCB4 and MAFB were detected in GWASs of alveolar cleft involvement and CL left sidedness, respectively. These subtype-specific associations were followed by case-only comparisons that reflect the presence or absence of alveolus cleft or left-sided bias of CL to confirm the specificity of the association signal to the particular subtype. Our results provide evidence of within-class CL subtype-specific genetic links for loci previously discussed in the context of primary OFC classes and demonstrate the value of granular OFC subtype characterization to capture trait-specific associations.

Several lines of evidence suggest that normal-range facial features and nonsyndromic orofacial clefts (OFCs) exhibit a shared genetic basis. Approaches designed to leverage this relationship hold the possibility of revealing new OFC risk loci by boosting discovery power. To test this idea, we applied a pleiotropy-informed genome-wide association study (GWAS) method (conditional false discovery rate [cFDR]-GWAS) with summary statistics from large, independent European GWASs of normal facial shape (n = 4,680; n = 3,566) and nonsyndromic cleft lip with or without cleft palate (nsCL/P; n = 3,969). The cFDR approach identified 21 independent genomic loci significantly associated with nsCL/P, providing further evidence of the interconnected genetic architecture between these traits. The five original nsCL/P GWAS signals were detected and joined by nine additional loci previously implicated in other OFC association studies. The remaining seven loci represent new nsCL/P genomic regions, and three of these replicated (p < 0.05) in an independent nsCL/P cohort: ASPSCR1, MSX2, and RALYL. A relaxed 10% cFDR-GWAS threshold identified 15 more independent loci with comparable effect sizes to those detected at the strict 5% threshold, two of which replicated: FHOD3 and SMARCA2. Gene expression patterns in major cell types and spatial transcriptomics data highlighted our gene candidates' roles in craniofacial development. In conclusion, applying an empirical Bayesian strategy to draw on association signals from genetically related traits can boost the power to identify and prioritize OFC risk loci missed by agnostic gene mapping approaches. These results hold promise that the cFDR-GWAS approach may be able to enhance our understanding of the genetic architecture of other structural birth defects.

Objective:Our understanding of the genetic causes of non-syndromic orofacial clefts (OFCs) is based largely upon genetic studies of common and rare nucleotide variants. Less is known about the role of copy number variations (CNVs) and the studies published to date have been limited to either small samples or targeted genomic regions. The objective of our study is to investigate the contribution of CNVs spread across the entire genome to OFC risk in a large multi-ancestry cohort. Methods:We utilized PennCNV on microarray genotyping data to detect CNVs in 10,240 participants (2,484 with clefts, 7,756 unaffected). 70,695 quality-filtered autosomal CNVs (49,660 deletions, 21,035 duplications) were used to assign normal/abnormal copy number statuses at 67,199 positions from the GRCh37 genome assembly. Genome-wide association was run between cleft status and copy number status. Results:We observed a highly significant association between OFCs and deletions on chromosome 7p14.1 (p=1.32e-35) driven by Central and South American ancestry (p=1.04e-25) participants, with less significant contributions from European (p=3.37e-08) and Asian (p=0.01) ancestry participants. We also observed four other loci with p-values below 10e-04. Conclusion:The 7p14.1 association observed in our study is a replication of two prior studies in independent cohorts of European ancestry. However, this locus lies in a T-cell receptor region that is subject to somatic rearrangements that decrease in frequency with age and may affect genetic association results. Our data show age effects as well as differences between blood and saliva samples. Thus, our results can be interpreted either as supporting a previously established association with orofacial clefts, or as questioning those previous results in favor of a hypothesis about the behavior of somatic rearrangements in T-cell receptor regions.

As data collecting technologies advance, data structures are getting more and more complex, from single vectors to multi-dimensional tensors. This article is motivated by a variable selection problem to detect important genes from an ultrahigh dimensional pool that are associated with human facial shape variations. We propose a data-driven trimmed feature screening method based on a tensor ridge regression model (TrimTenRidge) through setting thresholds on the tensor coefficients to perform a feature screening procedure. Unlike existing approaches, the TrimTenRidge does not require any sparse structures. In addition, it not only detects important predictors but also locates specific regions/components of the tensor response that are associated with each of the selected predictors. We prove the theoretical selection consistency and also assess its empirical performance through various simulation settings. The approach copes with ultra-high dimensional predictors and tensor responses simultaneously and contributes to the literature from theoretical, methodological, and five applicational aspects. We further apply the TrimTenRidge approach to genome-wide human facial shape data, from which the entire facial shapes form a 2,342× 7,160× 3 tensor, and we successfully detect several novel genetic loci and also confirm some existing findings that are associated to facial shape.

Periodontal disease and dental caries are two oral conditions that have been associated with atherosclerotic cardiovascular disease (ASCVD). However, it is unclear if one of the key mechanisms involved in this association could be a shared genetic susceptibility. The goal of this study was to explore whether there is an intersection of genetic loci among individuals with comprehensive oral examinations and subclinical ASCVD screenings. We leveraged data from oral and medical examinations obtained from the Dental and Heart Strategies Concentrating on Risk Evaluation (Dental/Heart SCORE) projects. Genome-wide association studies (GWASs) were performed independently in 552 participants (aged 45–75 years). The decayed, missing, or filled teeth index (DMFT) and periodontal disease indices were used to reflect oral conditions; coronary artery calcium scores (CAC) and carotid intima media thickness (CIMT) were analyzed as subclinical ASCVD traits. Single nucleotide variant (SNV) associations with oral and ASCVD traits were found; however, there were only a few regions of suggestive genetic loci overlap between these conditions. The most robust associations found for each phenotype are as follows: DMFT with rs79198416 (near CDC73/KCNT2; p = 7.57E-07), periodontal disease with rs73870587 (DIPK2A, p = 7.38E-08); CIMT with rs113152669 (LRP1B p = 4.07E-07), and CAC with rs76676138 (CNTNAP2; p = 2.47E-19). Although genetic associations were identified for each of the phenotypes of interest in the GWASs, there were no regions of shared genetic loci that significantly intersected across phenotypes. Thus, our results suggest that incorporation of environmental, behavioral, microbiome-related factors, and larger sample sizes, are warranted in future studies between oral and cardiovascular health.

ABSTRACT Background Fifth finger clinodactyly describes the conspicuous curvature of the fifth digit toward the other digits of the hand. Phenotypic expression can range from mild and almost imperceptible to severe, where function is impacted, and clinical intervention may be required. Although classically considered an autosomal dominant trait based on early family studies, no genes have been mapped for the trait. Further, there is epidemiological evidence that mild (typical‐range) fifth finger clinodactyly may have a different etiology than more severe forms. Methods In this retrospective cross‐sectional study, we carried out genome‐wide association mapping of common genetic variants for clinodactyly in three cohorts separately and combined results via meta‐analysis, treating the trait as either a continuous quantitative variable (nmeta = 631) or a binary outcome (nmeta = 1647). Results The vast majority of participants in these cohorts exhibited mild forms of clinodactyly. Both the individual cohort results and meta‐analyses revealed no genome‐wide significant loci. We identified several possible suggestive signals (p < 1 × 10−6), but these showed no evidence of replication. Conclusion While our results cannot definitively exclude the contribution of common variants to fifth finger clinodactyly due to the small sample size, they do suggest that the mild form of the trait is unlikely to be related to a major gene effect operating in a simple Mendelian manner.

Large-scale GWAS studies have uncovered hundreds of genomic loci linked to facial and brain shape variation, but only tens associated with cranial vault shape, a largely overlooked aspect of the craniofacial complex. Surrounding the neocortex, the cranial vault plays a central role during craniofacial development and understanding its genetics are pivotal for understanding craniofacial conditions. Experimental biology and prior genetic studies have generated a wealth of knowledge that presents opportunities to aid further genetic discovery efforts. Here, we use the conditional FDR method to leverage GWAS data of facial shape, brain shape, and bone mineral density to enhance SNP discovery for cranial vault shape. This approach identified 120 independent genomic loci at 1% FDR, nearly tripling the number discovered through unconditioned analysis and implicating crucial craniofacial transcription factors and signaling pathways. These results significantly advance our genetic understanding of cranial vault shape and craniofacial development more broadly.

BACKGROUND:Approximately one-third of breast cancer (BC) patients show poorer cognitive function (CF). Using DNA methylation (DNAm) data, here we aimed to identify genes and biological pathways associated with CF in postmenopausal women with early-stage hormone receptor-positive (HR+) BC. METHODS:Epigenome-wide association studies (EWAS) and differentially methylated region analyses were performed for each CF phenotype (seven objective domains and one subjective phenotype) using DNAm data from whole blood samples (n = 109) taken at the time of enrollment. RESULTS:When adjusting for age, verbal IQ scores, and global DNAm signature, cg10331779 near CTNND2 (p-value = 9.65×10-9) and cg25906741 in MLIP (p-value = 2.01×10-8) were associated with processing speed and subjective CF, respectively, while regions in/near SLC6A11, PRKG1/CSTF2T, and FAM3B for processing speed, and regions in/near PI4KB and SGCE/PEG10 for mental flexibility were differentially methylated. In addition, beta-estradiol was identified as a common upstream regulator for all the CF phenotypes, suggesting an essential role of estrogen in explaining variation in CF of HR+ BC patients. CONCLUSIONS:In our EWAS of 8 CF phenotypes, we found two epigenome-wide significant signals, one for processing speed and the other for subjective CF. We also found three differentially methylated regions associated with processing speed and two associated with mental flexibility. CLINICAL TRIAL REGISTRATION:www.clinicaltrials.gov identifier is NCT02793921.

Genotype-phenotype (G-P) analyses for complex morphological traits typically utilize simple, predetermined anatomical measures or features derived via unsupervised dimension reduction techniques (e.g. principal component analysis (PCA) or eigen-shapes). Despite the popularity of these approaches, they do not necessarily reveal axes of phenotypic variation that are genetically relevant. Therefore, we introduce a framework to optimize phenotyping for G-P analyses, such as genome-wide association studies (GWAS) of common variants or rare variant association studies (RVAS) of rare variants. Our strategy is two-fold: (i) we construct a multidimensional feature space spanning a wide range of phenotypic variation, and (ii) within this feature space, we use an optimization algorithm to search for directions or feature combinations that are genetically enriched. To test our approach, we examine human facial shape in the context of GWAS and RVAS. In GWAS, we optimize for phenotypes exhibiting high heritability, estimated from either family data or genomic relatedness measured in unrelated individuals. In RVAS, we optimize for the skewness of phenotype distributions, aiming to detect commingled distributions that suggest single or few genomic loci with major effects. We compare our approach with eigen-shapes as baseline in GWAS involving 8246 individuals of European ancestry and in gene-based tests of rare variants with a subset of 1906 individuals. After applying linkage disequilibrium score regression to our GWAS results, heritability-enriched phenotypes yielded the highest SNP heritability, followed by eigen-shapes, while commingling-based traits displayed the lowest SNP heritability. Heritability-enriched phenotypes also exhibited higher discovery rates, identifying the same number of independent genomic loci as eigen-shapes with a smaller effective number of traits. For RVAS, commingling-based traits resulted in more genes passing the exome-wide significance threshold than eigen-shapes, while heritability-enriched phenotypes lead to only a few associations. Overall, our results demonstrate that optimized phenotyping allows for the extraction of genetically relevant traits that can specifically enhance discovery efforts of common and rare variants, as evidenced by their increased power in facial GWAS and RVAS.

Background/Objectives: Maternal exposures are known to influence the risk of isolated cleft lip with or without cleft palate (CL/P)—a common and highly heritable birth defect with a multifactorial etiology. Methods: To identify new risk loci, we conducted a genome-wide gene–environment interaction (GEI) analysis of CL/P with maternal smoking and vitamin use in Filipinos (Ncases = 540, Ncontrols = 260). Since GEI analyses are typically low in power and the results can be difficult to interpret, we applied multiple testing frameworks to evaluate potential GEI effects: a one degree-of-freedom (1df) GxE test, the 3df joint test, and the two-step EDGE approach. Results: While no genome-wide significant interactions were detected, we identified 11 suggestive GEIs with smoking and 24 with vitamin use. Several implicated loci contain biologically plausible genes. Notable interactions with smoking include loci near FEZF1, TWIST2, and NET1. While FEZF1 is involved in early neuronal development, TWIST2 and NET1 regulate epithelial–mesenchymal transition, which is required for proper lip and palate fusion. Interactions with vitamins encompass CECR2—a chromatin remodeling protein required for neural tube closure—and FURIN, a critical protease during early embryogenesis that activates various growth factors and extracellular matrix proteins. The activity of both proteins is influenced by folic acid. Conclusions: Our findings highlight the critical role of maternal exposures in identifying genes associated with structural birth defects such as CL/P and provide new paths to explore for CL/P genetics.

Orofacial clefts (OFCs) are one of the most common structural birth defects, with the prevalence of OFC varying across populations, and studies on the causes of OFCs in diverse populations are necessary, but still limited. We analyzed whole genome sequencing data on 419 parent-child trios from the Philippines, a population with a particularly high rate of OFC. To identify novel genes for OFCs, we studied both common variation and de novo variants (DNVs). We identified a significant enrichment in both loss-of-function (N = 62; P = 8.34 × 10-5) and protein-altering DNVs (N = 394; P = 1.49 × 10-7) among OFC probands. Among the genes individually enriched for DNVs was GRHL2 (P = 6.60 × 10-6), where there were two DNVs, a stop-gain and a frameshift deletion. We then queried OFC trios from other cohorts in the Gabriella Miller Kids First program (total N = 1254) and GeneMatcher and identified an 89 kb de novo deletion in GRHL2 and a de novo 8q22.3 microdeletion with one breakpoint in GRHL2. Additionally, within the common variant analyses we found significant gene x gene interactions with GRHL2. GRHL2 is a conserved transcription factor involved in embryonic development, with truncating mutations causing autosomal dominant progressive hearing loss and missense variants causing autosomal recessive ectodermal dysplasia. Heterozygous variation in its homolog, GRHL3, causes Van der Woude syndrome and isolated cleft palate. Additionally, mice deficient for either Grhl2 or Grhl3 have craniofacial anomalies, including facial and palatal clefts, strongly supporting GRHL2 as a risk locus for OFCs.

Nonsyndromic orofacial clefts (OFCs) are common, heritable birth defects caused by both genetic and environmental risk factors. Despite the identification of many genetic loci harboring OFC-risk variants, there are many unknown genetic determinants of OFC. Furthermore, while the process of embryonic facial development is well characterized, the molecular mechanisms that underly it are not. This represents a major hurdle in understanding how disruptions in these biological processes result in OFC. Thus, we sought to identify novel OFC-risk loci through a genome-wide multi-ancestry study of five nested OFC phenotypes (isolated cleft lip [CLO], isolated cleft palate [CPO], cleft lip and palate [CLP], cleft lip with/without cleft palate [CL/P], and any cleft [ANY]) representing distinct cleft subtypes to identify subtype-specific signals and grouped types to maximize power to detect shared genetic effects. We performed genome-wide meta-analyses of these five OFC phenotypes from three cohorts totaling >14,000 individuals using METAL. In addition to replicating 13 known OFC-risk loci, we observed novel association in three regions: the 1p36.32 locus (lead variant rs584402, an intergenic variant, pCLO = 3.14e-8), the 7q33 locus (lead variant rs17168118, an intronic variant in CALD1, pCLP = 9.17e-9), and the 16p13.3 locus (lead variant rs77075754, an intronic variant in RBFOX1, pCL/P = 1.53e-9, pANY = 1.93e-9). We also observed a novel association within the known risk locus 8q22.1 that was independent of the previously reported signal (lead variant rs4735314, an intronic variant in ESRP1, pCLP = 1.07e-9, pCL/P = 3.88e-8). Next, we performed multi-tissue TWAS with s-MulTiXcan and identified four overlapping genes with significant genetically predicted transcription associated with OFC risk. These genes also overlapped the genome-wide significant association signals from the meta-analysis, including CALD1 and ESRP1 and known OFC-risk genes TANC2 and NTN1. Each of the newly reported loci has potential regulatory effects, including evidence of craniofacial enhancer activity, that offer new clues as to the molecule mechanisms underlying embryonic facial development.

Sepsis is a leading global health burden in children, and its unavoidable heterogeneity has hindered providing therapies beyond antibiotics and supportive care. Recently, we identified four computable phenotypes showing distinct cytokine profiles, clinical outcomes, and therapeutic response characteristics (PedSep-A, B, C, and D) in a multicenter pediatric sepsis cohort. In the cohort data, we collected whole-exome sequencing data and identified rare variants associated with PedSep-D phenotype by conducting a gene-based analysis in an aggregated fashion. As a result, one whole-exome significant gene (LTBP4) and two suggestive significant genes (PLA2G4E, CCDC157) showed association with PedSep-D, the phenotype characterized by the most severe outcomes and highest inflammation. The associated variants in LTBP4 were enriched for predicted deleterious effects based on established functional prediction metrics. All three associated genes are implicated in inflammation and immune cell activation based on existing gene function and expression data. Although the circulating cytokine profiles were overlapping between the rare variant carriers, we also identified gene-specific cytokine changes. Altogether, our study provides valuable insights into the genetic architecture of a pediatric sepsis phenotype with the highest inflammation level and the most severe outcomes, highlighting potential candidate genes and pathways for further biomarker and therapeutic studies.

Human facial shape, while strongly heritable, involves both genetic and structural complexity, necessitating precise phenotyping for accurate assessment. Common phenotyping strategies include simplifying 3D facial features into univariate traits such as anthropometric measurements (e.g., inter-landmark distances), unsupervised dimensionality reductions (e.g., principal component analysis (PCA) and auto-encoder (AE) approaches), and assessing resemblance to particular facial gestalts (e.g., syndromic facial archetypes). This study provides a comparative assessment of these strategies in genome-wide association studies (GWASs) of 3D facial shape. Specifically, we investigated inter-landmark distances, PCA and AE-derived latent dimensions, and facial resemblance to random, extreme, and syndromic gestalts within a GWAS of 8,426 individuals of recent European ancestry. Inter-landmark distances exhibit the highest SNP-based heritability as estimated via LD score regression, followed by AE dimensions. Conversely, resemblance scores to extreme and syndromic facial gestalts display the lowest heritability, in line with expectations. Notably, the aggregation of multiple GWASs on facial resemblance to random gestalts reveals the highest number of independent genetic loci. This novel, easy-to-implement phenotyping approach holds significant promise for capturing genetically relevant morphological traits derived from complex biomedical imaging datasets, and its applications extend beyond faces. Nevertheless, these different phenotyping strategies capture different genetic influences on craniofacial shape. Thus, it remains valuable to explore these strategies individually and in combination to gain a more comprehensive understanding of the genetic factors underlying craniofacial shape and related traits.

BackgroundParent-led toothbrushing with fluoride toothpaste is part of an evidence-based strategy to prevent caries in children. There is a gap in the literature regarding perceptions of how and when to assist a child with toothbrushing from the maternal perspective.MethodsA qualitative cross-sectional study was conducted with participants in North and North Central Appalachia to examine maternal perceptions of when and how to assist with toothbrushing. From 2018 through 2022, 301 mothers of children aged 3 through 5 years volunteered to participate in semistructured interviews from a more extensive parent study (Center for Oral Health Research in Appalachia cohort). The qualitative data were transcribed, coded, and analyzed using Nvivo software, Version 12 (QSR International). The data were analyzed using grounded theory, constant comparative method, and template analysis.ResultsA total of 301 mothers were interviewed for this study; 156 (52%) lived in West Virginia and 145 (48%) lived in Pittsburgh, Pennsylvania. Four main themes emerged: (1) assisting with child toothbrushing, (2) ceasing to provide assistance with child toothbrushing, (3) lacking recommendations from dental care professionals on child toothbrushing, and (4) adhering to recommendations from dental care professionals on child toothbrushing assistance.ConclusionsUnderstanding the factors that influence how parents brush their children’s teeth and the information they receive to guide daily dental hygiene behavior for children is essential in developing effective interventions for preventing caries in children.Practical ImplicationsThese insights can improve child toothbrushing quality through improved oral hygiene education, recommendations, terminology, and policies from the dental community.

Genome-wide association studies (GWAS) identified thousands of genetic variants linked to phenotypic traits and disease risk. However, mechanistic understanding of how GWAS variants influence complex morphological traits and can, in certain cases, simultaneously confer normal-range phenotypic variation and disease predisposition, is still largely lacking. Here, we focus on rs6740960, a single nucleotide polymorphism (SNP) at the 2p21 locus, which in GWAS studies has been associated both with normal-range variation in jaw shape and with an increased risk of non-syndromic orofacial clefting. Using in vitro derived embryonic cell types relevant for human facial morphogenesis, we show that this SNP resides in an enhancer that regulates chondrocytic expression of PKDCC - a gene encoding a tyrosine kinase involved in chondrogenesis and skeletal development. In agreement, we demonstrate that the rs6740960 SNP is sufficient to confer chondrocyte-specific differences in PKDCC expression. By deploying dense landmark morphometric analysis of skull elements in mice, we show that changes in Pkdcc dosage are associated with quantitative changes in the maxilla, mandible, and palatine bone shape that are concordant with the facial phenotypes and disease predisposition seen in humans. We further demonstrate that the frequency of the rs6740960 variant strongly deviated among different human populations, and that the activity of its cognate enhancer diverged in hominids. Our study provides a mechanistic explanation of how a common SNP can mediate normal-range and disease-associated morphological variation, with implications for the evolution of human facial features.

Evidence that breastfeeding impacts the facial features of children is conflicting. Most studies to date have focused on dental and skeletal malocclusion. It currently remains unclear whether such effects are of sufficient magnitude to be detectable on outward facial appearance. Here, we evaluate the extent to which maternally reported breastfeeding is associated with 3D facial shape in a large adolescent cohort. After extracting 3D facial surfaces from MR scans in 2275 9- and 10-year-old children and aligning the surfaces in dense correspondence, we analyzed the effect of breastfeeding on shape as a dichotomous (no/yes) and semi-quantitative (to assess duration in months) variable using partial least squares regression. Our results showed no effect (p = 0.532) when breastfeeding was dichotomized. However, when treated as a semi-quantitative variable, breastfeeding duration was associated with statistically significant changes in shape (p = 3.61x 10-4). The most prominent facial changes included relative retrusion of the central midface, zygomatic arches, and orbital regions along with relative protrusion of forehead, cheek, and mandible. The net effect was that as breastfeeding duration increased, the facial profile in children became flatter (less convex). The observed effects on the face, however, were subtle and likely not conspicuous enough to be noticed by most observers. This was true even when comparing the faces of children breastfed for 19-24 months to children with no reported breastfeeding. Thus, breastfeeding does appear to have detectable effect on outward facial appearance in adolescent children, but its practical impact appears to be minimal.

ObjectivesOral health during the perinatal period and beyond affects the health and well-being of women and their offspring. Oral self-care behaviours can maintain or improve oral health; depression or stress during the perinatal period may compromise these behaviours. The aim of the study was to investigate the independent and combined effects of depression and stress on oral self-care behaviours of perinatal women in Appalachia, given the high burden of oral disease in this region.MethodsA total of 1172 women in the first or second trimester of pregnancy were enrolled in the Center for Oral Health Research in Appalachia, cohort 2 (COHRA2) in West Virginia or Pittsburgh, Pennsylvania. Participants completed the Center for Epidemiological Studies Depression Scale, Perceived Stress Scale-10, and self-report items about oral self-care behaviours (i.e. toothbrushing and flossing) during pregnancy and five times in the 2+ years following birth. A Generalized Estimating Equation approach was used to analyse the longitudinal data.ResultsMaternal depression and stress were independently negatively related to toothbrushing and flossing frequency. These findings for toothbrushing were more pronounced in those with high levels of depression and high levels of stress, so there were both independent and combined effects. Frequency of toothbrushing and flossing stayed constant over time, so time was not associated with outcomes. About three-fourths of the sample reported toothbrushing levels that are consistent with established guidelines (i.e. two times daily), but almost half of the participants had very low levels of flossing (i.e. once or less a week).ConclusionInterventions targeting stress and depression throughout the perinatal period might be helpful in improving oral self-care behaviours and oral health among women in Appalachia, in addition to the benefit of decreasing emotional distress.