Papers by Sylvia Frazier-Bowers
FACE, 2022
Introduction: Articulation problems are seen in 80% to 90% of dentofacial deformity (DFD) subject... more Introduction: Articulation problems are seen in 80% to 90% of dentofacial deformity (DFD) subjects compared with 5% of the general population, impacting communication and quality of life, but the causal link is unclear. We hypothesize there are both qualitative (perceptual) and quantitative (spectral) differences in properties of stop (/t/ or /k/), fricative (/s/ or /ʃ/), and affricate (/tʃ/) consonant sounds and that severity of anterior open bite (AOB) jaw disharmonies correlates with degree of speech abnormality. Methods: To test our hypotheses, surgical orthodontic records and audio recordings were collected from DFD patients (n = 39 AOB, 62 controls). A speech pathologist evaluated subjects, and recordings were analyzed using spectral moment analysis (SMA) to measure sound frequency distortions. Results: Perceptually, there is a higher prevalence of auditory and visual speech distortions in AOB DFD patients when compared to controls. Quantitatively, a significant ( P
Journal of the American Dental Association, 2021
The Angle orthodontist, 2021
Orthodontics & Craniofacial Research, 2019
European Journal of Orthodontics, 2021
Summary Introduction Patients with dentofacial disharmonies (DFDs) seek orthodontic care and orth... more Summary Introduction Patients with dentofacial disharmonies (DFDs) seek orthodontic care and orthognathic surgery to address issues with mastication, esthetics, and speech. Speech distortions are seen 18 times more frequently in Class III DFD patients than the general population, with unclear causality. We hypothesize there are significant differences in spectral properties of stop (/t/ or /k/), fricative (/s/ or /ʃ/), and affricate (/tʃ/) consonants and that severity of Class III disharmony correlates with the degree of speech abnormality. Methods To understand how jaw disharmonies influence speech, orthodontic records and audio recordings were collected from Class III surgical candidates and reference subjects (n = 102 Class III, 62 controls). A speech pathologist evaluated subjects and recordings were quantitatively analysed by Spectral Moment Analysis for frequency distortions. Results A majority of Class III subjects exhibit speech distortions. A significant increase in the cen...
Journal of Dental Research
Tooth agenesis is one of the most common developmental anomalies affecting function and esthetics... more Tooth agenesis is one of the most common developmental anomalies affecting function and esthetics. The paired-domain transcription factor, Pax9, is critical for patterning and morphogenesis of tooth and taste buds. Mutations of PAX9 have been identified in patients with tooth agenesis. Despite significant progress in the genetics of tooth agenesis, many gaps in knowledge exist in refining the genotype-phenotype correlation between PAX9 and tooth agenesis. In the present study, we complete genetic and phenotypic characterization of multiplex Chinese families with nonsyndromic (NS) tooth agenesis. Direct sequencing of polymerase chain reaction products revealed 9 novel (c.140G>C, c.167T>A, c.332G>C, c.194C>A, c.271A>T, c.146delC, c.185_189dup, c.256_262dup, and c.592delG) and 2 known heterozygous mutations in the PAX9 gene among 120 probands. Subsequently, pedigrees were extended, and we confirmed that the mutations co-segregated with the tooth agenesis phenotype (with ...
American Journal of Orthodontics and Dentofacial Orthopedics
American Journal of Orthodontics and Dentofacial Orthopedics
Seminars in Orthodontics, 2015
Orthodontics & Craniofacial Research, 2009
Dental press journal of orthodontics
Dr. Frazier-Bowers is an associate professor at the University of North Carolina, Chapel Hill (UN... more Dr. Frazier-Bowers is an associate professor at the University of North Carolina, Chapel Hill (UNC-CH), in the Department of Orthodontics. She received a BA from the University of Illinois, Urbana-Champaign, and a DDS from the University of Illinois, Chicago. After completing the NIH Dentist-Scientist Program at UNC-CH in Orthodontics (Certificate, 97’) and Genetics and Molecular Biology (PhD, 99’), she completed a post-doctoral fellowship at the University of Texas Health Science Center, Houston (UTHSC), in the Department of Orthodontics. Leadership positions include president of local NC-AADR (North Carolina (2005-2006); director of the AADR Craniofacial Biology group (CBG) 2004-2007; IADR/AADR councilor for NC-AADR (2007, 2008, 2012) and for the CBG (2012-2015); member of Southern Association of Orthodontists Scientific Affairs Committee (2005-2013) and the American Association of Orthodontists Council on Scientific Affairs (2014 – Present). Dr. Frazier-Bowers also serves various...
Tooth agenesis (hypodontia or oligodontia) in its most severe form adversely impacts the quality ... more Tooth agenesis (hypodontia or oligodontia) in its most severe form adversely impacts the quality of life for affected individuals and their families. Characterized by the congenital absence of primary teeth, it is a hereditary disorder affecting up to 10% of the population. Mutations in two genes, MSX1 and PAX9, have been frequently reported as causative for hypodontia/oligodontia. Previous studies have shown the presence of genetic mutations within exons 1 and 2 of MSX1 and 1, 2 and 4 of PAX9. There have been multiple studies documenting sequence variations in the coding region of PAX9 exon 3; however, none are proven to be functional and/or causative mutations that results in tooth agenesis. Objective: The objective of this study is to determine a genotype/phenotype correlation with PAX9 exon 3 single nucleotide polymorphisms (SNPs) and the tooth agenesis phenotype. Methods: From a database of 41 individuals affected with tooth agenesis, we sequenced the entire coding regions of M...
Tooth development represents a chronologically specific process but third molar development has s... more Tooth development represents a chronologically specific process but third molar development has shown great variability across gender and ethnicity with increasing evidence of more precocious development in recent years. Data is lacking on the current trends in third molar development in a US population. Objective: The objective of our study is to test the hypothesis that third molars are present in an earlier developmental stage than in the past. Method: We utilized panoramic radiographs and the Demirjian staging criteria to evaluate the presence and developmental stage of third molars in children ranging from 7 to 13 years of age. Result: In comparison to a previous study (average age of occurrence of stage D about 16 years), our analysis of 62 panoramic radiographs showed that 100% of developing maxillary third molars in males had reached or surpassed stage D by 12 years of age and 43.75% had reached stage D at age 11. In females, 100% of developing maxillary third molars had rea...
Objectives: Idiopathic short root malformation (IRM) is not well documented likely because it is ... more Objectives: Idiopathic short root malformation (IRM) is not well documented likely because it is poorly understood and the etiology remains unknown. The anomaly may be misdiagnosed as resorption. This hypothesis-generating study aimed to systematically characterize individuals with idiopathic short root malformation and no history of orthodontic treatment in order to better define the condition and improve diagnosis. Methods: Sixteen individuals (ranging from 9-48 years of age) were included in this study based on the identification of shortened permanent tooth roots. Digital panorex and periapical films were analyzed to characterize the pathology (ie pattern and frequency of affected teeth). Crown-to- root ratios of the affected teeth were used to characterize the extent of malformation. When available a comparison of crown-to-root ratios at 2 ages was completed. Results: Fifteen of 16 individuals were of Latino descent and 1 individual was of Filipino descent. In all individuals e...
Introduction: Class III malocclusion is often described as a challenging clinical problem to mana... more Introduction: Class III malocclusion is often described as a challenging clinical problem to manage due to difficulty in predicting timing and extent of disproportionate growth. Further, the clinical variation of the Class III dentofacial phenotype has been shown to include distinct sub phenotypes that carry treatment recommendations ranging from orthodontic camouflage to orthognathic surgery. A more systematic approach to diagnosis of Class III malocclusion will facilitate a more accurate treatment choice. Objective : We developed the Statistical Model for Prediction of Class III (SMP3) formula SMP3 based on a previously described five -cluster classification of Class III phenotypes using 60 cephalometric variables. In this study we aimed to test the hypothesis that the SMP3 is an accurate method to diagnose Class III patients. Methods: Sixty cephalometric measurements for a cohort (N=84) of previously clinically diagnosed Class III patients were applied to the SMP3 formula to dete...
Proceedings of the National Academy of Sciences, 2014
TET/JBP enzymes oxidize 5-methylpyrimidines in DNA. In mammals, the oxidized methylcytosines (oxi... more TET/JBP enzymes oxidize 5-methylpyrimidines in DNA. In mammals, the oxidized methylcytosines (oxi-mCs) function as epigenetic marks and likely intermediates in DNA demethylation. Here we present a method based on diglucosylation of 5-hydroxymethylcytosine (5hmC) to simultaneously map 5hmC, 5-formylcytosine, and 5-carboxylcytosine at near-base-pair resolution. We have used the method to map the distribution of oxi-mC across the genome of Coprinopsis cinerea, a basidiomycete that encodes 47 TET/JBP paralogs in a previously unidentified class of DNA transposons. Like 5-methylcytosine residues from which they are derived, oxi-mC modifications are enriched at centromeres, TET/JBP transposons, and multicopy paralogous genes that are not expressed, but rarely mark genes whose expression changes between two developmental stages. Our study provides evidence for the emergence of an epigenetic regulatory system through recruitment of selfish elements in a eukaryotic lineage, and describes a method to map all three different species of oxi-mCs simultaneously.
Craniofacial and Dental Developmental Defects, 2015
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Papers by Sylvia Frazier-Bowers