Improving accuracy of early dental carious lesions detection using deep learning-based automated method.

OBJECTIVE: To investigate the effectiveness of a convolutional neural network (CNN) in detecting healthy teeth and early carious lesions on occlusal surfaces and to assess the applicability of this deep learning algorithm as an auxiliary aid. MATERIALS AND METHODS: A total of 2,481 posterior teeth (2,459 permanent and 22 deciduous teeth) with varying stages of carious lesions were classified according to the International Caries Detection and Assessment System (ICDAS). After clinical evaluation, ICDAS 0 and 2 occlusal surfaces were photographed with a professional digital camera. VGG-19 was chosen as the CNN and the findings were compared with those of a reference examiner to evaluate its detection efficiency. To verify the effectiveness of the CNN as an auxiliary detection aid, three examiners (an undergraduate student (US), a newly graduated dental surgeon (ND), and a specialist in pediatric dentistry (SP) assessed the acquired images (Phase I). In Phase II, the examiners reassessed the same images using the CNN-generated algorithms. RESULTS: The training dataset consisted of 8,749 images, whereas the test dataset included 140 images. VGG-19 achieved an accuracy of 0.879, positive agreement of 0.827, precision of 0.949, negative agreement 0.800, and an F1-score of 0.887. In Phase I, the accuracy rates for examiners US, ND, and SP were 0.543, 0.771, and 0.807, respectively. In Phase II, the accuracy rates improved to 0.679, 0.886, and 0.857 for the respective examiners. The number of correct answers was significantly higher in Phase II than in Phase I for all examiners (McNemar test;P<0.05). CONCLUSIONS: VGG-19 demonstrated satisfactory performance in the detection of early carious lesions, as well as an auxiliary detection aid. CLINICAL RELEVANCE: Automated detection using deep learning algorithms is an important aid in detecting early caries lesions and improves the accuracy of the disease detection, enabling quicker and more reliable clinical decision-making.

Temporomandibular Disorders at the Preoperative Time of Orthognathic Surgery.

Individuals seeking orthodontic treatment combined with orthognathic surgery (OS) have a high prevalence of temporomandibular disorders (TMDs), but the relationship between TMD diagnoses and dentofacial deformities (DFDs) is still controversial. Therefore, this cross-sectional study with a comparison group aimed to analyze the association between dentofacial deformities and TMDs. METHODOLOGY: Eighty patients undergoing OS were consecutively selected from the stomatology department of the Federal University of Paraná between July 2021 and July 2022. Forty patients who would undergo OS composed the group of participants with DFD, and forty who received other types of attention and did not present changes in the dental bone bases formed the group without DFDs (DFDs and no DFDs groups). The groups were matched for sex, age, and self-reported ethnicity. The diagnostic criteria for TMDs (DC/TMDs) were used to diagnose TMD based on the Axis I criteria. The psychosocial aspects, oral behaviors in wakefulness, and sleep bruxism were evaluated through the Axis II criteria. The data were analyzed with a 5% significance level. RESULTS: The presence of DFDs was significantly associated with arthralgia (p = 0.01). The other types of TMDs were not associated with DFDs. Comorbidities, habits, and psychosocial variables were not associated with DFDs at a level of 0.05. (p > 0.05). In analyzing the participants with arthralgia, the ones with this condition presented higher frequencies of sleep bruxism (p = 0.046). CONCLUSIONS: Participants with DFDs presented a significantly higher frequency of arthralgia when compared to no DFDs ones. Sleep bruxism was associated with the occurrence of joint TMDs in these participants.

Are Premature Birth and Low Birth Weight Associated with Delay on the Eruption of Deciduous Teeth? A Systematic Review and Meta-analysis

ABSTRACT Objective: To investigate whether children with premature birth (PB) and/or with low birth weight (LBW) have different tooth eruption patterns than those born at term or with normal weight. Material and Methods: Searches were performed in the PubMed, Cochrane Library, Sc1opus, Web of Science, LILACS, and BBO databases as well as the grey literature. Three independent reviewers were involved in study selection, data extraction, and bias assessment. The risk of bias was assessed using the Modified Newcastle-Ottawa Scale. Meta-analysis was conducted to compute the mean difference (MD) in mean chronological or adjusted age at the eruption of the first deciduous tooth between preterm children and those born at full term. The GRADE approach was used. Results: Among a total of 316 articles identified, 21 were eligible for inclusion and three were included in the meta-analysis. PB was associated with the delay in the first tooth deciduous eruption when chronological age was considered (MD: 1.36; 95%CI: 1.02-1.69) but not when considering adjusted age (MD: -0.30; 95%CI: -0.67-0.07). The evidence was graded as having very low quality. Conclusion: Based on a low certainty of evidence the PB is associated with the delayed eruption of the first deciduous tooth when considering chronological age but not when adjusted age is considered.

Restoration of molars affected by molar-incisor hypomineralization using the occlusal replica technique / Restauração de molares afetados pela Hipomineralização Molar-Incisivo utilizando a técnica da réplica oclusal

ABSTRACT The aim of this study was to report the clinical case of an 8-year-old male patient seen at the Pediatric Dentistry outpatient clinic at the Universidade Federal do Paraná, Brazil, diagnosed with molar-incisor hypomineralization (MIH) after presenting with pain in teeth 16, 36, and 46, which had extensive atypical cavities and opacities on the adjacent enamel. A diagnostic wax-up of affected teeth was performed for manufacture of silicone occlusal matrix. Encapsulated high-viscosity glass ionomer cement was handled and inserted into the occlusal matrix which was fitted onto the teeth by slight finger pressure. After setting time, excess of material was removed, and occlusion was checked. A flowable resin coating material was applied, and the restorations were finished. Six months later, the restorations performed for treatment of the severe MIH lesions proved to be efficient, lowering the sensitivity reported by the patient, reshaping the teeth, improving their function, and refining dental esthetics.

RESUMO O objetivo deste estudo foi relatar um caso clínico de um paciente com diagnóstico de Hipomineralização de Molares e Incisivos (HMI). Paciente do sexo masculino, de 8 anos de idade, compareceu à clínica de Odontopediatria da Universidade Federal do Paraná com queixa de dor nos dentes 16, 36 e 46 - os quais apresentavam extensas cavitações atípicas com opacidades no esmalte adjacente. O enceramento diagnóstico dos dentes afetados foi realizado para a confecção das matrizes oclusais de silicone. Cimento ionômero de vidro de alta viscosidade encapsulado foi manipulado e inserido na matriz oclusal, a qual foi encaixada sobre os dentes, exercendo-se leve pressão digital. Após a presa do material os excessos foram removidos e a oclusão foi checada. Aplicou-se uma camada de resina fluída de cobertura e as restaurações foram finalizadas. Após seis meses, as restaurações realizadas para tratar as lesões severas de HMI mostraram-se eficazes, reduzindo a sensibilidade relatada pelo paciente, além de reestabelecerem a anatomia, função e estética dentária.

Association between genetic polymorphisms in the melatonin receptor type 1 A gene and sleep bruxism.

OBJECTIVE: This study evaluated whether single nucleotide polymorphisms in the melatonin receptor type 1 A gene are associated with sleep bruxism in a Brazilian population. DESIGN: Individuals with suspected sleep-related problems were evaluated using polysomnography, following the recommendations proposed by the American Academy of Sleep Medicine and the Research Diagnostic Criteria for Temporomandibular Disorders. Deoxyribonucleic acid (DNA) samples were collected, and three single nucleotide polymorphisms in the melatonin receptor type 1 A gene (rs13140012, rs6553010, and rs6847693) were selected and genotyped using real-time polymerase chain reaction (RT-PCR). Chi-square and odds ratio tests were used to analyze genotypes and alleles individually, while using the plink software for haplotypes. A confidence interval of 95% was considered, and statistical significance was set at p < 0.05. RESULTS: This study included 48 individuals aged between 21 and 80 years, with 27 males and 21 females. From this sample, 17 individuals were diagnosed with sleep bruxism and 31 without bruxism. No associations were found between sleep bruxism and single nucleotide polymorphisms in either the genotypic, allelic, dominant, or recessive models (p > 0.05). Haplotype genetic analysis also did not reveal any association between single nucleotide polymorphisms and sleep bruxism (p > 0.05). CONCLUSION: The genetic polymorphisms rs6553010, rs13140012, and rs6847693 were not associated with sleep bruxism in the studied population.

How is the quality of the available evidence on molar-incisor hypomineralization treatment? An overview of systematic reviews.

OBJECTIVE: This overview analyzed the quality of the systematic reviews (SRs) available on treatments for molar-incisor hypomineralization (MIH). MATERIAL AND METHODS: Six electronic databases were searched (PubMed/MEDLINE, Scopus, Web of Science, LILACS, Brazilian Bibliography of Dentistry and Cochrane Library) until March 2022. Two reviewers independently performed the selection, the quality assessment (Assessment of Multiple Systematic Reviews 2 - AMSTAR-2), and the risk of bias assessment of the SR (Risk of Bias in Systematic Reviews - ROBIS). RESULTS: Two hundred nine records were retrieved; after removing duplicates and applying the inclusion/exclusion criteria, 5 SRs remained. Three SRs were rated as showing critically low methodological quality and high risk of bias, and two were rated as moderate methodological quality and low risk of bias. The identified treatments that may be suitable for MIH were classified as (1) non-invasive - casein incorporated into toothpaste and sugar-free chewing gum, toothpaste containing arginine, 0.4% stannous fluoride gel; fluoride varnish; (2) micro-invasive - resin sealants for pits and fissures, microabrasion, dental whitening, resin infiltration; (3) invasive - ART restorations, indirect restorations (metal, composite, or ceramic); and (4) mixed intervention - stainless steel crowns. CONCLUSION: Despite the considerable number of published papers included in this set of systematic reviews, the evidence supporting the effectiveness of treatments for treating MIH is limited due to the methodological quality and risk of bias of the systematic reviews, as well as the quality of the primary studies (PROSPERO: CRD42020144831). CLINICAL RELEVANCE: Different treatments have been purposed for MIH treatment, but there is still not enough scientific evidence of good quality for the establishment of a definitive clinical protocol for the treatment of MIH.

Restorative Techniques for Permanent First Molars Affected by Hypomineralization: A Systematic Review.

Purpose: There are several restorative modalities for molar hypomineralization, but there is no consensus on the best approach. The purpose of this review was to describe restorative approaches applied to permanent first molars (PFM) with molar hypomineralization (MH). Methods: This review was registered (PROSPERO database CRD42017078336). Searches were conducted in the PubMed, Scopus, Web of Science, LILACS, BBO, and Cochrane Library databases and grey literature. From a total of 1,751 studies, 12 that compared restorative treatments for PFM with MH were included. The risk of bias of the studies was assessed using the Cochrane Collaboration and the Newcastle-Ottawa Scale. The success rate was the primary outcome. Results: The restorative treatment options were direct restorations with amalgam, glass ionomer cement, and resin-based composite as well as indirect restorations with stainless steel, porcelain, ceromer, and gold crowns. The restorative techniques, considering the type of isolation and the removal of caries and hypomineralization, vary between the study. There was also a lack of standard clinical criteria for restorative evaluation. The follow-up period ranged from six to 216 months. The success of direct restorations ranged from 86.3 to 100 percent. For indirect restorations, success ranged from 91.3 to 100 percent. Conclusions: There were multiple clinical protocols for MH. The studies presented heterogeneity in the restoration technique, time, and clinical criteria for restorative follow-up. Direct restorations with glass ionomer cement and resin-based composite could be the first choices for restoration. Further randomized clinical trials on a restorative treatment for MH are needed.

Genetic polymorphisms are associated with alterations in anxiety levels and vital signs in patients undergoing third molar extractions.

OBJECTIVE: The objective of this study was to evaluate the association between SLC6A4 (rs1042173 and rs3813034), DRD2 (rs6275 and rs6276), ANKK1 (rs1800497), and COMT (rs174675) genetic polymorphisms and alterations in anxiety levels and vital signs in individuals undergoing third molar extractions. STUDY DESIGN: One hundred sixty-eight individuals were evaluated at the pre-, trans-, and postoperative periods by checking systolic blood pressure, diastolic blood pressure, heart rate, respiratory rate, and body temperature. Anxiety levels were assessed using the State-Trait Anxiety Inventory (STAI). Buccal mucosa cells were collected for genetic evaluation using real-time polymerase chain reaction. Statistical analysis was performed at a significance level of 5%. RESULTS: The level of anxiety was associated with rs1800497 for STAI-Trait (P = .031) and rs174675 for STAI-State (P = .007). Considering the vital signs, there was a significant difference between the values of respiratory rate and rs1042173 (P = .029), rs3813034 (P = .024), and rs6275 (P = .025). The diastolic blood pressure values differed significantly for rs1042173 (P = .042), and the body temperature values differed significantly for rs174675 (P = .016). CONCLUSIONS: Polymorphisms in SLC6A4, DRD2, ANKK1, and COMT genes could be associated with alterations in anxiety levels and vital signs in individuals undergoing third molar extractions.

Is there an association of genetic polymorphisms of the catechol-O-methyltransferase gene (rs165656 and rs174675) and the 5-hydroxytryptamine receptor 2A gene (rs4941573 and rs6313) with sleep bruxism in individuals with obstructive sleep apnea?

OBJECTIVE: To evaluate the association of single-nucleotide polymorphisms within the catechol-O-methyltransferase and 5-hydroxytryptamine receptor 2A genes with sleep bruxism in individuals diagnosed with obstructive sleep apnea. DESIGN: Sixty-nine individuals with suspected sleep-related problems were evaluated by polysomnography, following the recommendations of the American Academy of Sleep Medicine. Deoxyribonucleic acid (DNA) samples were collected only from 48 of the study participants because of missing polysomnographic data. DNA samples were collected and two single-nucleotide polymorphisms in the 5-hydroxytryptamine receptor 2A encoding HTR2A gene (rs4941573 and rs6313) and two in the catechol-O-methyltransferase gene (rs165656 and rs174675) were selected to be genotyped using real-time polymerase chain reaction. The association between sleep bruxism and genetic polymorphisms was investigated by recessive and dominant models. Association analyses were performed using a 95% confidence interval and the level of statistical significance was p < 0.05. RESULTS: From the 69 study participants, 48 were included in the polymorphism analysis and sleep bruxism was present in 35.4%. No significant differences were observed in the dominant and recessive models (p > 0.05). Haplotype and diplotype analyses revealed the predicted four haplotypes and two diplotypes were not associated with sleep bruxism. CONCLUSION: Polymorphisms rs174675 and rs165656 in the catechol-O-methyltransferase gene and rs4941573 and rs6313 in the 5-hydroxytryptamine receptor 2A gene were not significantly associated with sleep bruxism in individuals with obstructive sleep apnea.

Performance of ICDAS e-learning program in teaching graduate students on the detection of occlusal caries / Desempenho do programa de aprendizagem eletrônico ICDAS no ensino de alunos de pós-graduação na detecção de cáries oclusais

ABSTRACT Objective: The aim was evaluate the validity and reproducibility of the International Caries Detection and Assessment System (ICDAS) in detecting occlusal caries among graduate students after training using the e-learning program. Methods: A sample of forty-two primary teeth with different ranges of occlusal caries was selected. All teeth were mounted on a wax support and standardized photographs (EOS Rebel XTI, Canon, NY, USA) of the occlusal surfaces were taken. An experienced researcher randomly selected one specific site on the occlusal surface of each tooth to be examined later. Fifteen graduate students with no previous experience in the ICDAS scores completed the ICDAS e-learning program in Portuguese. After the training, visual examination of the occlusal surfaces was taken twice, independently, with a two-week interval. After visual examination, the teeth were longitudinally sectioned 1mm away from the previously selected occlusal site. The teeth were fixed on a wax support and photographed. Histological analysis was performed from these photographs by an experienced researcher to evaluate the depth of demineralization. Results: The Intraclass Correlation Coefficient (ICC) inter-examiner values among all participants varied from 0.54 to 0.96 and intra-examiner ICC reproducibility of the examiners ranges from 0.61 to 0.85, showing good to excellent reproducibility. For detection of enamel and dentine lesions (D1), ICDAS obtained sensitivity 0.835 and specificity 0.756. For dentine lesions (D3), the method revealed an increase in sensitivity but specificity was similar to D1. Conclusion: ICDAS e-learning training program was efficient for the training of caries lesions detection among graduate students.

RESUMO Objetivo: O objetivo foi avaliar a validade e a reprodutibilidade do Sistema Internacional de Detecção e Avaliação de Cárie (ICDAS) na detecção de cárie oclusal entre estudantes de pós-graduação após o treinamento usando o programa de e-learning. Métodos: Foi selecionada uma amostra de 42 dentes decíduos com diferentes faixas de cárie oclusal. Todos os dentes foram montados em um suporte de cera e foram tiradas fotografias padronizadas (EOS Rebel XTI, Canon, NY, EUA) das superfícies oclusais. Um pesquisador experiente selecionou aleatoriamente um local específico na superfície oclusal de cada dente para ser examinado posteriormente. Quinze estudantes de pós-graduação sem experiência anterior com o ICDAS concluíram o programa de e-learning em português. Após o treinamento, o exame visual das superfícies oclusais foi realizado duas vezes, independentemente, com intervalo de duas semanas. Após o exame visual, os dentes foram seccionados longitudinalmente a 1mm do local oclusal previamente selecionado. Os dentes foram fixados em um suporte de cera e fotografados. A análise histológica foi realizada a partir dessas fotografias por um pesquisador experiente para avaliar a profundidade da desmineralização. Resultados: Os valores interexaminadores do Coeficiente de Correlação Intraclasse (ICC) entre todos os participantes variaram de 0,54 a 0,96 e a reprodutibilidade intra-examinador do ICC dos examinadores variou de 0,61 a 0,85, mostrando reprodutibilidade boa a excelente. Para detecção de lesões de esmalte e dentina (D1), o ICDAS obteve sensibilidade 0,835 e especificidade 0,756. Para lesões de dentina (D3), o método revelou um aumento na sensibilidade, mas a especificidade foi semelhante ao D1. Conclusão: O programa de treinamento em e-learning do ICDAS foi eficiente no treinamento de detecção de lesões de cárie em estudantes de pós-graduação.

Knowledge of Dentists and Dental Undergraduates Related to COVID-19

Abstract Objective: To assess the knowledge of Brazilian dentists and final-year dental undergraduates concerning COVID-19. Material and Methods: We conducted a self-administered online questionnaire about the symptoms, incubation period, and transmission routes of COVID-19. In total, there were three questions addressing these topics and 15 correct answers, so each participant could score from 0 to 15 points. Besides that, data such as sex, age, education level, years of work experience and place of work were collected. All data were submitted to statistical analysis with a 5% significance level. Results: 476 participants were recruited. Regarding the respondents' perception of the most common symptoms of COVID-19, 99.4% responded fever, 95.2% cough, and 99.2% dyspnea. About the incubation period, 56.3% answered from 1 to 14 days. About the transmission routes, 98.3% recognized transmission through droplets, 80.3% through direct contact with infected persons, and 70.4% through indirect routes. The median knowledge score was 10 (4 - 14). Regarding the socio-demographic variables, participants aged 30 years or more had a higher score than those aged up to 29 years old (p=0.004). For education level, specialist dentists presented a higher score than undergraduates (p=0.006), general dentists (p=0.048) and Ph.D. (p=0.016). Participants with 15 years or more of work experience had a higher score than undergraduates (p=0.003). Concerning the workplace, participants working in the public sector had a higher score than those working in the private sector or universities (p=0.015). Conclusion: Participants recognized the main symptoms, incubation period, and transmission routes of the COVID-19 virus; however, the knowledge level of specialist dentists, older dentists, more experienced dentists, and dentists working in the public sector was higher than the other participants (AU).

Can Hemophilia Impact on the Oral Health Conditions of Children and Adolescents? A Systematic Review and Metanalysis

Abstract Objective: To analyze if the oral health conditions in children and adolescents are associated with hemophilia (PROSPERO-42020168192). Material and Methods: The search strategy was performed in PubMed, Scopus, Lilacs/BBO, Web of Science, Cochrane, and Grey literature databases. Two independent researchers assessed the risk of bias in these studies by the Newcastle-Ottawa Scale. For the meta-analysis, the clinical conditions data were extracted as numerical variables according to their indexes, such as dental caries experience (dmft/DMFT), gingival condition (Modified Gingival Index - IGM), and oral hygiene (Plaque Index - PI). The quality of the evidence of the meta-analysis was evaluated by the GRADE tool (GRADEproGDT). Results: From a total of 431 studies, 27 were included, and 10 were included in the meta-analysis. The studies presented a moderate risk of bias, ranging from 2 to 7 points. The dental caries experience in primary (-0.62; CI95%: -1.68-0.43) and permanent dentitions (-0.05; CI95%: -0.69-0.59), gingival condition (-0.12; CI95%: -0.27-0.03), and oral hygiene (0.36; CI95%: -0.06-0.77) did not differ between the groups. Conclusion: Based on studies with very weak evidence, there were no differences in the oral health conditions of children and adolescents with and without hemophilia (AU).

Daily Toothbrushing Frequency and the Association with Parental Report of Dental Pain and Discomfort in Preschool Children

Abstract Objective: To evaluate the impact of daily toothbrushing frequency on parental reports of dental pain and discomfort in preschoolers. Material and Methods: An observational cross-sectional study was conducted involving 376 children between four and five years of age at public preschools in the city of Campo Magro, Brazil. Parents/guardians answered a socioeconomic questionnaire that contained a single question on the child's daily toothbrushing frequency and the Brazilian version of the Dental Discomfort Questionnaire (DDQ-B). Statistical analysis involved bivariate and multivariate Poisson regression analyses (α=0.05). Results: After the adjustments in the multivariate analysis, the prevalence of dental pain and discomfort was lower among children whose last visit to the dentist was for prevention (PR = 4.42; 95% CI: 1.75- 11.14; p=0.002) and those with a higher daily toothbrushing frequency (PR = 2.13; 95% CI: 1.12-4.05; p=0.021). Conclusion: A lower toothbrushing frequency is associated with parental reports of dental pain and discomfort in preschoolers. Educational and preventive measures that stimulate an increase in daily toothbrushing frequency can contribute to a better oral health status in preschoolers, consequently, less prevalence of dental pain and discomfort.

Inheritance pattern of molar-incisor hypomineralization.

The aim of this study was to investigate the segregation patterns of molar incisor hypomineralization (MIH) in families, given the evidence that its etiology is influenced by genetics. Clinically, MIH may be detected in parents and/or siblings of MIH-affected children. Our study included children with at least one first permanent molar affected by MIH (proband) and their first-degree relatives (parents and siblings). The participants were examined clinically to detect MIH, according to the European Academy of Paediatric Dentistry criteria (2003). A total of 101 nuclear families (391 individuals) were studied. Proband diagnosis was followed by MIH classification of the subject, his parents and siblings, as affected, unaffected, or unknown. Segregation analysis was performed using the multivariate logistic regression model of the Statistical Analysis for Genetic Epidemiology package, and segregation models (general transmission, environmental, major gene, dominant, codominant and recessive models). The Akaike information criterion (AIC) was used to evaluate the most parsimonious model. In all, 130 affected individuals, 165 unaffected individuals, and 96 unknown individuals were studied. Severe MIH was found in 50.7% of the cases. A segregation analysis performed for MIH revealed the following different models: environmental and dominance (p = 0.05), major gene (p = 0.04), codominant (p = 0.15) and recessive models (p = 0.03). According to the AIC values, the codominant model was the most parsimonious (AIC = 308.36). Our results suggest that the codominant model could be the most likely for inheriting MIH. This result strengthens the evidence that genetic factors, such as multifactorial complex defect, influence MIH.

Association of possible sleep bruxism with daytime oral habits and sleep behavior in schoolchildren.

Objective: To Determine whether possible sleep bruxism (PSB) is associated with daytime oral habits and sleep behavior in schoolchildren.Methods: A cross-sectional study was conducted with a representative sample of 8-to-10-year-old children (n = 544). The Sleep Behavior Questionnaire (SBQ) was administered to evaluate sleep behavior. Daytime oral habits were evaluated using the Nordic Orofacial Test-Screening.Results: The prevalence of PSB was 21% and was significantly higher in children with reports of awake bruxism (p < .001; PR = 2.76; 95% CI: 2.01-3.79), snoring (p < .001; PR = 1.93; 95% CI: 1.41-2.65), and sucking/biting the lips daily (p = .034; PR = 1.73; 95% CI: 1.08-2.78). No socioeconomic characteristics were associated with PSB in the final model.Conclusion: Possible sleep bruxism in schoolchildren is associated with possible awake bruxism, snoring, sleep fragmentation, and daytime sleepiness.

Inheritance pattern of molar-incisor hypomineralization

Abstract The aim of this study was to investigate the segregation patterns of molar incisor hypomineralization (MIH) in families, given the evidence that its etiology is influenced by genetics. Clinically, MIH may be detected in parents and/or siblings of MIH-affected children. Our study included children with at least one first permanent molar affected by MIH (proband) and their first-degree relatives (parents and siblings). The participants were examined clinically to detect MIH, according to the European Academy of Paediatric Dentistry criteria (2003). A total of 101 nuclear families (391 individuals) were studied. Proband diagnosis was followed by MIH classification of the subject, his parents and siblings, as affected, unaffected, or unknown. Segregation analysis was performed using the multivariate logistic regression model of the Statistical Analysis for Genetic Epidemiology package, and segregation models (general transmission, environmental, major gene, dominant, codominant and recessive models). The Akaike information criterion (AIC) was used to evaluate the most parsimonious model. In all, 130 affected individuals, 165 unaffected individuals, and 96 unknown individuals were studied. Severe MIH was found in 50.7% of the cases. A segregation analysis performed for MIH revealed the following different models: environmental and dominance (p = 0.05), major gene (p = 0.04), codominant (p = 0.15) and recessive models (p = 0.03). According to the AIC values, the codominant model was the most parsimonious (AIC = 308.36). Our results suggest that the codominant model could be the most likely for inheriting MIH. This result strengthens the evidence that genetic factors, such as multifactorial complex defect, influence MIH.

Effect of different factors on patient perception of surgical discomfort in third molar surgery

Abstract: The aim of this study was to evaluate patient perception of surgical discomfort in third molar surgery and the association with clinical variables and polymorphisms associated with the FKBP5, SLC6A4, and COMT genes. This cross-sectional observational study was carried out on 196 participants aged between 18 and 64 years at the Federal University of Paraná in 11 months. The intensity of surgical discomfort was assessed using the QCirDental questionnaire. Data on surgical and individual procedures were also cataloged. The oral health related quality of life was assessed by the Oral Health Impact Profile questionnaire (OHIP-14). The DNA sample was obtained from cells of the oral mucosa. Five markers of the FKBP5, SLC6A4, and COMT genes were genotyped. The data were submitted to statistical analysis with a significance level of 5%. Women reported greater intensity of discomfort associated with third molar surgery compared to men (p = 0.001). In the recessive model, the AA genotype of the rs3800373 marker was associated with greater surgical discomfort (p = 0.026). Therefore, women and individuals of the AA genotype for the rs3800373 marker in the FKBP5 gene reported greater surgical discomfort associated with third molar surgery.

Effect of different factors on patient perception of surgical discomfort in third molar surgery.

The aim of this study was to evaluate patient perception of surgical discomfort in third molar surgery and the association with clinical variables and polymorphisms associated with the FKBP5, SLC6A4, and COMT genes. This cross-sectional observational study was carried out on 196 participants aged between 18 and 64 years at the Federal University of Paraná in 11 months. The intensity of surgical discomfort was assessed using the QCirDental questionnaire. Data on surgical and individual procedures were also cataloged. The oral health related quality of life was assessed by the Oral Health Impact Profile questionnaire (OHIP-14). The DNA sample was obtained from cells of the oral mucosa. Five markers of the FKBP5, SLC6A4, and COMT genes were genotyped. The data were submitted to statistical analysis with a significance level of 5%. Women reported greater intensity of discomfort associated with third molar surgery compared to men (p = 0.001). In the recessive model, the AA genotype of the rs3800373 marker was associated with greater surgical discomfort (p = 0.026). Therefore, women and individuals of the AA genotype for the rs3800373 marker in the FKBP5 gene reported greater surgical discomfort associated with third molar surgery.

Polymorphisms in COL2A1 gene in Adolescents with Temporomandibular Disorders.

OBJECTIVES: Temporomandibular disorder (TMD) is considered a functional disorder with multifactorial aspects. The goal of this study was to investigate if genetic polymorphisms in the COL2A1 gene could be associated with TMD in adolescents. STUDY DESIGN: The case group (TMD-affected) included individuals diagnosed with any of the following TMD subgroups according to the RDC/TMD criteria: myofascial pain, disc displacements and arthralgia. Genomic DNA for molecular analysis was extracted from buccal cells and genetic polymorphisms in COL2A1 were genotyped by real time polymerase chain reactions using the TaqMan assay. Data were analyzed using the Epi Info 3.5.7 and Stata software. RESULTS: 249 subjects were included in this study (148 subjects "affected" by TMD). There were no significant differences between the affected and unaffected individual (p>0.05), for TMD, arthralgia and myofascial pain however, rs2276454 was borderline in the genotype distribution (p=0.07) and was associated with disc displacement (p=0.03) in the allelic distribution. Recessive model showed significant differences between groups for with disc displacement (p=0.02). CONCLUSIONS: Genetic polymorphisms in COL2A1 are not associated with myofascial pain, arthralgia or TMD in adolescents but this study provides evidence that rs2276454 is involved in the disc displacement of the temporomandibular joint.