Genetics and sleep bruxism: a systematic review and meta-analysis of studies with twins.

OBJECTIVE: To systematically review the literature regarding the concordance of sleep bruxism (SB) between monozygotic (MZ) and dizygotic (DZ) twins. METHODS: The registration for this systematic review was accomplished in the International Prospective Register of Systematic Reviews (PROSPERO, No. CRD42021251751). As of July 2022, four databases were searched, including PubMed, Scopus, Embase, and Web of Science, as well as the grey literature in Google Scholar and OpenGrey. Observational studies evaluating SB in MZ and DZ twins of any age and sex were included. For the evaluation of the risk of bias, the Joanna Briggs checklist was utilized. The certainty of evidence was assessed via the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Pooled and subgroup meta-analyses were performed to estimate concordance of SB ​​between twins (p < 0.05). RESULTS: In total, 3,155 records were identified. In the qualitative analysis, eleven studies were included; of these, seven were included in the meta-analysis. The majority of the articles exhibited a low risk of bias (63.6%). Greater SB concordance was observed between MZ twins than between DZ twins in the analysis of general concordance (OR = 1.47; 95% CI = 1.07-2.02) and also positive concordance (OR = 1.53; 95% CI = 1.29-1.81). Within the subgroup analyses, the significance of the findings remained only for the reported/self-reported SB regarding general concordance (OR = 1.44; 95% CI = 1.07-1.95) and positive concordance (OR = 1.55; 95% CI = 1.28-1.88). Low certainty of the evidence was observed for the general concordance analysis, while moderate certainty was observed for the positive concordance. CONCLUSION: There was a higher concordance of SB in MZ twins compared to DZ twins, indicating a possible genetic influence on the condition's occurrence.

Association between genetic factors and molar-incisor hypomineralisation or hypomineralised second primary molar: A systematic review.

OBJECTIVE: To determine the association between genetic factors and molar-incisor hypomineralisation (MIH) and/or hypomineralised second primary molars by means of a systematic review. DESIGN: A search was performed in Medline-PubMed, Scopus, Embase and Web of Science databases; manual search and search in gray literature were also performed. Selection of articles was performed independently by two researchers. A third examiner was involved in cases of disagreement. Data extraction was performed using an Excel® spreadsheet and independent analysis was performed for each outcome. RESULTS: Sixteen studies were included. There was an association between MIH and genetic variants related to amelogenesis, immune response, xenobiotic detoxification and other genes. Moreover, interactions between amelogenesis and immune response genes, and SNPs in the aquaporin gene and vitamin D receptors were associated with MIH. Greater agreement of MIH was found in pairs of monozygotic twins than dizygotic twins. The heritability of MIH was 20 %. Hypomineralised second primary molars was associated with SNPs in the hypoxia-related HIF-1 gene and methylation in genes related to amelogenesis. CONCLUSION: With very low or low certainty of evidence, an association was observed between MIH and SNPs in genes associated with amelogenesis, immune response, xenobiotic detox and ion transport. Interactions between genes related to amelogenesis and immune response as well as aquaporin genes were associated to MIH. With very low certainty of evidence, hypomineralised second primary molars was associated to a hypoxia-related gene and to methylation in genes related to amelogenesis. Moreover, higher agreement of MIH in pairs of monozygotic twins than dizygotic twins was observed.

Breathing problems, being an only child and having parents with possible sleep bruxism are associated with probable sleep bruxism in preschoolers: a population-based study.

PURPOSE: To determine the prevalence of probable sleep bruxism (SB) in preschoolers and associated factors. METHODS: A cross-sectional, population-based study was carried out with 862 dyads of parents/preschoolers aged 5 from Teresina, Brazil. Data collection was performed through a questionnaire answered by parents/guardians about socioeconomic, demographic, and health condition data. Each child was examined for diagnosis of probable SB based on the presence of dental wear associated or not with the report of teeth grinding by parents/guardians. The analysis of independent variables was stratified into four levels of determinants: demographic characteristics of the child (distal), characteristics of the family, environmental factors (intermediate), and health conditions (proximal). Descriptive analysis and bivariate and multivariate Poisson's regression were performed using a hierarchical approach (p < 0.05). RESULTS: The prevalence of probable SB was 36%. In the final adjusted multivariate hierarchical model, a preschooler who was the only child (PR = 1.25; 95%CI = 1.02-1.51), with breathing problems (PR = 1.43; 95%CI = 1.19-1.73), and having parents/guardians with possible sleep bruxism (PR = 1.65; 95%CI = 1.32-2.07) had a higher prevalence of probable SB. CONCLUSION: The prevalence of probable SB in preschoolers was high and associated with the condition of being an only child, the presence of breathing problems, and having parents/guardians with possible sleep bruxism.

Molar-incisor hypomineralization in quilombola children and adolescents: A study of prevalence and associated factors.

OBJECTIVES: This cross-sectional observational study determined the prevalence and factors associated with molar-incisive hypomineralization (MIH) in quilombola children and adolescents in north-eastern Brazil. METHODS: The sample consisted of 251 children and adolescents (8 to 14 years old) living in the rural quilombola community Lagoas in São Raimundo Nonato, Piauí (census population). Sociodemographic and health-related data were collected from pre-, peri- and post-natal health records and a clinical examination for MIH diagnosis was performed by four previously trained and calibrated examiners. Descriptive data analysis and Poisson regression were performed. The magnitude of the association was determined by adjusted prevalence ratio (PR) and confidence intervals (95% CI). RESULTS: The prevalence of MIH was 46.6%. The presence of MIH was associated with gestational diabetes (PR = 2.49, 95% CI 2.08-2.99; p <0.001) and acute foetal distress (PR = 1.39; 95% CI 1.04-1.86; p = 0.025). CONCLUSION: It was concluded that the prevalence of MIH in the quilombola community was high and associated with gestational diabetes and acute foetal distress.

Endodontic Treatment of Primary Molars with Antibiotic Paste: A Report of 38 Cases.

OBJECTIVE: This study presents 38 cases of primary molars with necrotic pulps treated with antibiotics-based paste. CASE REPORT: The technique consisted of necrotic tissue removal of the pulp chamber, using spoons excavators and low speed drills. Pulp cavity was washed with saline solution and dried with sterile cotton balls. Then an antibiotic paste composed of chloramphenicol, tetracycline, zinc oxide and eugenol - CTZ paste - was inserted at the entrance of root canals. Patients were evaluated clinically and radiographically at different times. The criteria that defined clinical success were the lack of periapical abscess and mobility compatible with chronological age. Radiographic assessments consisted in absence of radiolucency in the region of root bifurcation and pathological bone resorption. CONCLUSION: There were 100% and 93% of clinical and radiographic success, respectively. The results suggest that the CTZ paste is an optional therapy for pulp of primary molars.

[Epidemiological surveillance of dental fluorosis in a city with a tropical climate with a fluoridated public drinking water supply]. / Vigilância epidemiológica da fluorose dentária em município de clima tropical com água de abastecimento público fluoretada.

The scope of this study was to evaluate the prevalence and severity of dental fluorosis among 11 to 14-year-old schoolchildren in Teresina, Piauí, Brazil, which is a tropical city with a fluoridated public drinking water supply. It involved a cross-sectional observational study on a sample of 571 students in public and private schools. Informed Consent forms were approved for the data collection and the exams were conducted at the schools. Data were recorded on a questionnaire answered by the parents, regarding the socioeconomic and demographic characteristics and oral hygiene habits of the sample. The dental exam was performed qualified dental sugeons. The Thylstrup-Fejerskov (TF) index was used. The prevalence of fluorosis was 77.9%, and only 12.5% of the affected children had TF ≥ grade 3 (with aesthetic damage). The premolars were the teeth most affected by fluorosis. Among the students with the highest severity of fluorosis, 98.6% belonged to the lowest social bracket (> B2), 91.5% were born and had always lived in Teresina, 94.4% consumed water from the fluoridated public supply, 76% used toothpaste for children and 64% of mothers reported that they swallowed toothpaste. The prevalence of fluorosis was high, though the severity was low in individuals exposed to fluoridation since birth.

Crown-root fracture with pulp exposure: a case report with 16-year follow-up.

A 12-year-old boy presented for dental care 35 days after he fell from his bicycle. Clinical and radiographic examinations revealed a longitudinal crown-root fracture with pulp exposure in the maxillary left central incisor. The radiograph also suggested necrosis of the maxillary right central incisor. Urgent treatment of the left central incisor involved gingivectomy followed by autogenous bonding of the tooth fragment with self-curing composite resin. Immediately after bonding, coronal access was prepared, chemical and mechanical preparation was completed, and a calcium hydroxide intracanal dressing was placed. One week after the initial appointment, endodontic treatment was initiated in the right central incisor. The root canal of the maxillary left central incisor was maintained with calcium hydroxide paste (replaced at 45-day intervals) for 1 year and then definitively obturated. At the 16-year follow-up, satisfactory periodontal, esthetic, and clinical conditions were observed, and a radiograph revealed no resorption or periapical changes.

Epidemiologic Study of Molar-incisor Hypomineralization in Schoolchildren in North-eastern Brazil.

PURPOSE: To determine the prevalence of molar-incisor hypomineralization (MIH) in children and possible factors associated with this disorder. METHODS: This was a cross-sectional observational study of 594 11- to 14-year-olds from Teresina, Piauí, Brazil. The diagnosis of MIH was made based on criteria set by the European Academy of Pediatric Dentistry. To investigate possible associated factors, mothers completed a questionnaire. A descriptive analysis of the data, chi-square, Mann-Whitney, and Fisher tests and Poisson regression (PR) were performed. RESULTS: The prevalence of MIH was 18.4 percent (95 percent confidence interval [CI] equals 15.20 to 21.50). The maxillary molars were the teeth most affected by MIH (36.1 percent). MIH patients showed a higher number of mean DMF-T (PR equals 2.18; 95 percent CI equals 1.46 to 2.85) than those not affected by the condition. There was an association between MIH and preterm birth (PR equals 1.76; 95 percent CI equals 1.22 to 2.12) and between MIH and respiratory distress at birth (PR equals 1.83; 95 percent CI equals 1.25 to 2.18). CONCLUSIONS: The prevalence of MIH in schoolchildren was 18.4 percent. Those with MIH had a greater mean DMF-T than those without MIH. Preterm birth and respiratory distress were associated with MIH.

The impact of a dental program for maternal and infant health on the prevalence of dental fluorosis.

PURPOSE: This study's purpose was to investigate the prevalence of dental fluorosis in children, whose parents had participated in an oral health program when the children were between zero and three years old, residing in a city with fluoridated water. METHODS: Group 1 consisted of 128 eight- to 12-year-olds whose parents had visited a program on at least five occasions when the children were zero to three years old and received education about tooth-brushing and the proper use of fluoridated toothpaste in this young age group. The prevalence of dental fluorosis in the permanent maxillary incisors, using the Thylstrup-Fejerskov index, in Group 1 was compared to that of an age-matched group of children (n=128) whose parents had not participated in the program (Group 2). RESULTS: Group 1 mothers reported higher education levels (P<.05). Group 1 children had a significantly lower prevalence (∼42 percent) and severity (P<.05) of dental fluorosis than those in the control group (∼61 percent). CONCLUSION: Children whose parents participated in a dental program that included counselling on the proper amount of fluoridated toothpaste when their children were between zero and three years old presented less frequently with dental fluorosis than a control group when examined at eight to 12 years old.

Reattachment of fractured fragment of an anterior tooth: case report and nine-year follow-up.

This article reports the treatment and follow-up of a 10-year-old boy who had a politraumatic accident that resulted in severe displacement and fracture of the maxillary right central incisor. After clinical and radiographic examination, the tooth fragment was bonded with adhesive and the tooth crown underwent nonrigid splinting. Follow-up appointments were scheduled once a week during the first month, once during the second month, and every three months thereafter. Each follow-up appointment included a clinical examination, followed by radiographic and pulp sensitivity tests. After the fifth year, pulp necrosis was diagnosed following a sensitivity test and a periapical radiograph. Endodontic treatment was performed; the chemical-mechanical preparation and root canal fillings used calcium hydroxide paste manipulated with saline solution. The abovementioned paste was replaced twice during the first month; after that, propylenoglycol was used as the vehicle for manipulating the calcium hydroxide. The filling paste was replaced whenever the radiographic image showed resorption of the paste. The root canals were filled definitively seven years postaccident. Nine years postaccident, clinical and radiographic examination revealed a normal aspect.

Interdisciplinary approach to traumatized permanent anterior teeth: case report and 10-year follow-up.

This article presents a case report (including the 10-year follow-up) of a 10-year-old patient who suffered displacement of the maxillary right central incisor, intrusion of the maxillary left central incisor, and crown fractures to the mesial angles of these teeth as a result of dental trauma. Treatment involved an interdisciplinary approach that utilized a pediatric dentist, an endodontist, and an orthodontist.

Dental team management for a patient with Klippel-Feil syndrome: case report.

Klippel-Feil syndrome (KFS) is a rare congenital abnormality characterized by a short neck, a low posterior hairline, and limited head movement. Occasionally, patients with KFS may also show signs of deafness, intellectual disability, cardiac malformation, palpebral ptosis, facial nerve paralysis, cleft palate, and scoliosis. Although some researchers have documented this syndrome, scant attention has been paid to craniomaxillofacial manifestations and dental treatment of patients with KFS. The objective of this case report was to describe the planning and execution of dental treatment for a 10-year-old male patient with KFS.

MDM2, P53, P21WAF1 and pAKT protein levels in genesis and behaviour of adenoid cystic carcinoma.

BACKGROUND: MDM2, P53, P21(WAF1) and pAKT are proteins associated with the balance between cell death and survival. There are many hypotheses regarding the role of these proteins in salivary gland tumours. However, many molecular events that activate or inactivate regulatory genes remain unknown. The aim of this study was to evaluate and to correlate MDM2, P53, P21(WAF1) and pAKT protein expressions in adenoid cystic carcinomas (ACC). METHODS: Twenty-two cases of ACC were evaluated by immunohistochemistry and one cell line derived from ACC was analyzed by Western Blotting and immunofluorescence techniques. RESULTS: Strong MDM2 and pAKT, variable P53 and null P21 expressions were found in the cases analyzed, but no statistical correlation was established when comparing MDM2 and pAKT expressions in the 3 different ACC subtypes. The ACC cell line showed intense nuclear and cytoplasmatic MDM2 and pAKT expressions and null P53 and P21 expressions. CONCLUSIONS: Results indicate that MDM2 and pAKT are related to the tumorigenesis of ACC, but they might not be directly connected to tumour progression. We also demonstrate that the pAKT pathway is active in ACC and it seems to be activating the MDM2 shuttle from the cytoplasm to the nucleus, where it phosphorylates P53 and carries it to the cytoplasm for degradation.

Blue nevus: report of a case.

Blue nevus is a benign, acquired melanocytic lesion that typically manifests as an asymptomatic, slate-blue or blue-black, smooth-surfaced macule or papule. It usually measures less than 4 mm in diameter. Intraoral melanocytic nevi are uncommon compared to those found in the skin, with the exception of the blue nevus. The blue nevus is proportionally more prevalent in oral mucosa and represents the second most common form of nevus, accounting for 16.5% to 36% of all oral nevi. The palate is the predominant location for blue nevi, accounting for 87% of all oral cases, although other lesions are found in this region as well. This paper presents a case of common blue nevus of the hard palate in a 76-year-old woman, describes the clinical and histological aspects of the nevus, and discusses the difference between benign and malignant melanocytic lesion in the palate.

Mdm2, p53, p21 and pAKT protein pathways in benign neoplasms of the salivary gland.

The p53 protein can be altered virtually in all human cancers. In the absence of p53 mutations, p53 inactivation is possible via complex formation with other proteins, such as Mdm2. Previous studies have shown an overexpression of Mdm2 and lack of p53 expression in pleomorphic adenomas. The pAkt protein is closely related to Mdm2, and has not been previously reported in salivary gland tumors. The aim of this study was to analyze the expression of Mdm2, p53, p21 and pAkt proteins in pleomorphic adenomas and myoepitheliomas by immunohistochemistry, Western blotting and immunofluorescence techniques. Overexpression of Mdm2 and pAkt was present in all the cell lines and tumors studied, whereas the expression of p53 and p21 proteins was considered absent. In conclusion, the signaling pathway in benign salivary gland neoplasm showed an important participation of Mdm2 overexpression protein in tumor formation, progression through inactivation of p53 action, or both, and of pAkt overexpression through increased translocation of Mdm2 protein to cellular nuclei.