No association between dopamine D2 receptor (DRD2) alleles and crack/cocaine dependence in Brazilians

INTRODUCTION: The causal mechanisms behind crack/cocaine use are still unknown, but genetic influences are suggested. OBJECTIVE: To investigate the relationship between the genetic polymorphism TaqI (rs1800497) in the dopamine D2 receptor (DRD2) gene and susceptibility to crack/cocaine dependence in a group of addicts to crack/cocaine and a non-addicted group. METHODS: The case group (n=515) was composed of crack/cocaine-dependent men and the control group (n=106) comprised men who were considered not dependent on crack/cocaine. The oral hygiene habits, decayed, missing, and filled teeth index, gingival index, and plaque index were evaluated. The reference single nucleotide polymorphism (rs1800497 C/T) of the DRD2 gene was genotyped by a real-time polymerase chain reaction technique. Student's t-tests for independent samples or the non-parametric Mann-Whitney test were used to compare groups regarding quantitative variables. RESULTS: The case group showed a mean time of 9.91±7.03 years of crack use, and 61.06±92.96 stones/week. The socio-demographic profile of the sample was White, single men, with basic education, blue-collar worker, smoker, and reporting alcohol use. There was a high frequency of gingival inflammation, plaque accumulation, and caries experience. For all genetic models tested, there was no significant difference in the genotypic frequency in rs1800497 of the DRD2 gene, between case and control groups (p>0.05). CONCLUSION: The genetic variant in the DRD2 did not increase the vulnerability to develop crack/cocaine dependence. The complex genetic nature of crack/cocaine dependence and a large variation of DRD2 allele frequencies, depending on the population group sampled, could be one explanation for the no association.

Lack of association between delayed tooth emergence and single nucleotide polymorphisms in estrogen receptors

Abstract The purpose of the study was to investigate the association between single nucleotide polymorphisms (SNPs) in genes encoding estrogen receptors (ESR1 and ESR2, respectively) and delayed tooth emergence (DTE). This cross-sectional study was composed of biological unrelated children of both sexes, age ranging from 11 to 13 years old. DTE was defined when the successor primary tooth was still present in the oral cavity after its exfoliation time or the absence of the permanent tooth emergence into the oral cavity. Children were diagnosed with DTE when they had at least one delayed permanent tooth, according to age of exfoliation of each tooth proposed by The American Dental Association. Genomic DNA from saliva was used to evaluate the SNPs in ESR1 (rs9340799 and rs2234693) and ESR2 (rs1256049 and rs4986938) using Real-Time PCR. Chi-square or Fisher exact tests and Logistic Regression adjusted by age and gender were performed. SNP-SNP interaction was accessed by multifactor dimensionality reduction (MDR) analysis also adjusted by gender and age. The established alpha of this study was 5%. Among 537 included children, 296 (55%) were in the "DTE" group and the 241 (45%) were in the "Control" group. Age and gender were not statistically different among the groups (p>0.05). Genotype distribution of the SNPs rs9340799, rs2234693, rs1256049 and rs4986938 were not associated with DTE (p> 0.05). The models elected by MDR were not statistically significant either. Conclusions: The studied SNPs in ESR1 and ESR2 were not associated with permanent DTE.

RESUMO O objetivo do presente estudo foi investigar a associação entre polimorfismos de nucleotídeo único (SNPs) em genes que codificam receptores de estrógeno (ESR1 e ESR2, respectivamente) e o retardo na emergência dentária (DTE). Este estudo transversal foi composto por crianças biológicas não relacionadas de ambos os sexos, com idades entre 11 e 13 anos. O DTE foi definido pela presença do dente decíduo na cavidade bucal após seu tempo e também, quando as crianças apresentaram pelo menos um dente permanente com atraso. O DNA genômico foi usado para avaliar os SNPs em ESR1 (rs9340799 e rs2234693) e ESR2 (rs1256049 e rs4986938) usando PCR em tempo real. Foram realizados testes Qui-quadrado ou exato de Fisher e Regressão Logística ajustados por idade e sexo. A interação SNP-SNP foi acessada pela análise de redução de dimensionalidade multifatorial (MDR), também ajustada por sexo e idade. O alfa de 5% foi estabelecido. Entre 537 crianças incluídas, 296 (55%) estavam no grupo "DTE" e 241 (45%) estavam no grupo "Controle". A idade e o sexo não foram estatisticamente diferentes entre os grupos (p> 0,05). A distribuição de genótipos dos SNPs rs9340799, rs2234693, rs1256049 e rs4986938 não foi associada ao DTE (p> 0,05). Os modelos eleitos pelo MDR também não foram estatisticamente significativos. Conclusões: Os SNPs estudados na ESR1 e ESR2 não foram associados ao DTE na dentição permanente.

Proteomic Expression Profile in Human Temporomandibular Joint Dysfunction.

Temporomandibular joint dysfunction (TMD) is a multifactorial condition that impairs human's health and quality of life. Its etiology is still a challenge due to its complex development and the great number of different conditions it comprises. One of the most common forms of TMD is anterior disc displacement without reduction (DDWoR) and other TMDs with distinct origins are condylar hyperplasia (CH) and mandibular dislocation (MD). Thus, the aim of this study is to identify the protein expression profile of synovial fluid and the temporomandibular joint disc of patients diagnosed with DDWoR, CH and MD. Synovial fluid and a fraction of the temporomandibular joint disc were collected from nine patients diagnosed with DDWoR (n = 3), CH (n = 4) and MD (n = 2). Samples were subjected to label-free nLC-MS/MS for proteomic data extraction, and then bioinformatics analysis were conducted for protein identification and functional annotation. The three TMD conditions showed different protein expression profiles, and novel proteins were identified in both synovial fluid and disc sample. TMD is a complex condition and the identification of the proteins expressed in the three different types of TMD may contribute to a better comprehension of how each pathology develops and evolutes, benefitting the patient with a focus-target treatment.

Association of estrogen receptor alpha 1 and TMJ dysfunction: A pilot study.

OBJECTIVE: Temporomandibular disorder (TMD) is a multifactorial condition and the most common cause of orofacial pain, affecting mostly women, which points to a female hormone predilection. Therefore, the aim of this study was to analyze the association between TMD and estrogen receptor alpha 1 expression in disks of patients with TMD and condyle fracture (CFx). STUDY DESIGN: Forty specimens (from 27 patients) included n = 8 CFx, n = 21 anterior disk displacement with reduction (ADDwR), and n = 11 anterior disk displacement without reduction (ADDwoR). Age, area, and intensity of immunostaining were statistically compared between CFx, ADDwR, and ADDwoR groups using analysis of variance and Kruskal-Wallis analysis (P < .05). RESULTS: No significant difference between CFx, ADDwR, and ADDwoR groups with respect to age and expression of estrogen receptor alpha 1 was observed on immunohistochemical examination. CONCLUSION: No association of estrogen receptor alpha 1 expression and age was found in the CFx, ADDwR, and ADDwoR groups.

The role of polymorphism of the IL6 gene in tooth replantation.

The absence or presence of root resorption on the root surface of a replanted tooth indicates an immune-inflammatory reaction. Since interleukin-6 (IL-6) is considered an inflammatory marker in bone resorption, this study aimed to investigate the association between clinical variables and polymorphisms in IL6, with the outcome of replanted teeth at 1-year follow-up. Altogether, 127 avulsed teeth that were replanted and had their root canals treated were selected for this study. Periapical radiographs were taken after replantation and after 1 year. Real-time PCR was used to genotype IL6 polymorphisms. Chi-square and 'Z' tests were performed to verify the association between genetic variables and the prognosis of replanted teeth (P < 0.05). An association was observed between the rs2069843 polymorphism of IL6 and the outcome of replanted teeth (P < 0.05). The rs2069843 polymorphism of IL6 may influence the outcome of avulsed and replanted teeth in the first year post-trauma.

Lack of association between delayed tooth emergence and single nucleotide polymorphisms in estrogen receptors.

The purpose of the study was to investigate the association between single nucleotide polymorphisms (SNPs) in genes encoding estrogen receptors (ESR1 and ESR2, respectively) and delayed tooth emergence (DTE). This cross-sectional study was composed of biological unrelated children of both sexes, age ranging from 11 to 13 years old. DTE was defined when the successor primary tooth was still present in the oral cavity after its exfoliation time or the absence of the permanent tooth emergence into the oral cavity. Children were diagnosed with DTE when they had at least one delayed permanent tooth, according to age of exfoliation of each tooth proposed by The American Dental Association. Genomic DNA from saliva was used to evaluate the SNPs in ESR1 (rs9340799 and rs2234693) and ESR2 (rs1256049 and rs4986938) using Real-Time PCR. Chi-square or Fisher exact tests and Logistic Regression adjusted by age and gender were performed. SNP-SNP interaction was accessed by multifactor dimensionality reduction (MDR) analysis also adjusted by gender and age. The established alpha of this study was 5%. Among 537 included children, 296 (55%) were in the "DTE" group and the 241 (45%) were in the "Control" group. Age and gender were not statistically different among the groups (p>0.05). Genotype distribution of the SNPs rs9340799, rs2234693, rs1256049 and rs4986938 were not associated with DTE (p> 0.05). The models elected by MDR were not statistically significant either. Conclusions: The studied SNPs in ESR1 and ESR2 were not associated with permanent DTE.

Calcium and Phosphorus Levels in Saliva are Influenced by Genetic Polymorphisms in Estrogen Receptor Alpha and Microrna17.

Homeostasis between salivary calcium and phosphorus is important for maintaining oral health. The aim of this study was to evaluate if polymorphisms in ESR1 (Estrogen Receptor Alpha), ESR2 (Estrogen Receptor Beta) and miRNA17 (microRNA17) are associated with calcium and phosphorus levels in saliva. Saliva from 276 12-year-old children were collected by masticatory stimulation and calcium and phosphorus levels were determined by Mass Spectrometry. Genomic DNA was extracted from remaining saliva and genetic polymorphisms in ESR1 (rs12154178, rs1884051, rs9340799 and rs2234693), in ESR2 (rs4986938 and rs1256049) and in miRNA17 (rs4284505) were genotyped using TaqMan chemistry and a real-time PCR equipment. Statistical differences in genotype and allele distributions between 'low' and 'high' calcium and phosphorus levels were determined using chi-square or Fisher´s exact tests. The analysis was also adjusted by sex (alpha of 5%). ESR1 rs9340799 had the less common genotype associated with higher calcium levels (p=0.03). The less common allele of ESR1 rs1884051 was associated with lower phosphorus levels (p=0.005) and there was an excess of heterozygotes for miRNA17 rs4284505 among individuals with lower calcium levels (p=0.002), both adjusted by sex. This study provides evidence that genetic polymorphisms in ESR1 and miRNA17 are involved in determining salivary calcium and phosphorus levels.

Calcium and phosphorus levels in saliva are influenced by genetic polymorphisms in estrogen receptor alpha and microrna17

Abstract Homeostasis between salivary calcium and phosphorus is important for maintaining oral health. The aim of this study was to evaluate if polymorphisms in ESR1 (Estrogen Receptor Alpha), ESR2 (Estrogen Receptor Beta) and miRNA17 (microRNA17) are associated with calcium and phosphorus levels in saliva. Saliva from 276 12-year-old children were collected by masticatory stimulation and calcium and phosphorus levels were determined by Mass Spectrometry. Genomic DNA was extracted from remaining saliva and genetic polymorphisms in ESR1 (rs12154178, rs1884051, rs9340799 and rs2234693), in ESR2 (rs4986938 and rs1256049) and in miRNA17 (rs4284505) were genotyped using TaqMan chemistry and a real-time PCR equipment. Statistical differences in genotype and allele distributions between 'low' and 'high' calcium and phosphorus levels were determined using chi-square or Fisher´s exact tests. The analysis was also adjusted by sex (alpha of 5%). ESR1 rs9340799 had the less common genotype associated with higher calcium levels (p=0.03). The less common allele of ESR1 rs1884051 was associated with lower phosphorus levels (p=0.005) and there was an excess of heterozygotes for miRNA17 rs4284505 among individuals with lower calcium levels (p=0.002), both adjusted by sex. This study provides evidence that genetic polymorphisms in ESR1 and miRNA17 are involved in determining salivary calcium and phosphorus levels.

Resumo A homeostasia entre cálcio e fósforo salivares é importante para a manutenção da saúde bucal. O objetivo deste estudo foi avaliar se polimorfismos genéticos no receptor de estrógeno alfa (ESR1), receptor de estrógeno beta (ESR2) e no microRNA17 (microRNA17) estão associados com os níveis salivares de cálcio e fósforo. Saliva de 276 crianças com 12 anos de idade foi coletada com estímulo mastigatório e os níveis de cálcio e fósforo foram determinados por Espectrofotometria de Massa. O DNA genômico foi extraído da saliva remanescente e os polimorfismos genéticos em ESR1 (rs12154178, rs1884051, rs9340799 e rs2234693), em ESR2 (rs4986938 e rs1256049) e no miRNA17 (rs4284505) foram genotipados pela reação em cadeia da polimerase em tempo real utilizando sondas TaqMan. As diferenças estatísticas nas distribuições alélicas e genotípicas entre "baixo" e "alto" níveis de cálcio e fósforo foram determinadas usando os testes qui-quadrado e teste exato de Fisher. As análises foram ajustadas por sexo (alfa de 5%). O polimorfismo rs9340799 em ESR1 foi o genótipo menos comum associado com altos níveis de cálcio (p=0,03). O alelo menos comum em ESR1 rs1884051 foi associado com baixos níveis de fósforo (p=0,005) e houve um excesso de heterozigotos para miRNA17 rs4284505 entre os indivíduos com baixos níveis de cálcio salivar (p=0,002), ambos ajustados pelo sexo. Este estudo fornece evidências de que polimorfismos genéticos em ESR1 e miRNA17 estão envolvidos na determinação dos níveis de cálcio e fósforo salivares.

RANK/RANKL/OPG gene polymorphisms and loss of orthodontic mini-implants.

OBJECTIVE: To investigate the association of genetic polymorphisms (tagSNPs type) of RANK/RANKL/OPG genes with the loss of orthodontic mini-implants (MIs). SETTING AND SAMPLE POPULATION: One hundred and thirty-five patients of both sexes, with mean age of 48.7 ± 10 (20-76 years), were studied. The control group was composed of 104 patients, with no MI lost and functioning for at least 6 months and the case group, of 31 patients with at least one MI lost. MATERIALS AND METHODS: Cells were obtained by mouthwash with 3% glucose solution for 1 minute and scraping the buccal mucosa with sterilized spatula. DNA was extracted from buccal epithelial cells with 10 M ammonium acetate and 1 mM EDTA. Genotyping was performed by the real-time polymerase chain reaction (PCR) technique. Univariate and multivariate analyses were performed (P < .05). RESULTS: No markers were associated with MI loss after Benjamini and Hochberg false discovery rate correction of Univariate tests. In the multivariate analysis, the variables that associated with MI loss were the number of MIs installed (P < .000) and the polymorphism rs8086340 in the RANK gene (P = .018). CONCLUSION: A higher number of MIs installed (P < .000) and polymorphism rs8086340 in the RANK gene (P = .018) were associated with loss of orthodontic MIs after multivariate analysis.

A complete physical mapping of the vitamin D receptor gene for dental implant loss: A pilot study.

OBJECTIVES: The aim of this pilot case-control study was to investigate the association of clinical variables and genetic polymorphisms in the vitamin D receptor gene (VDR) with dental implant loss. MATERIAL AND METHODS: This study was carried out with 244 individuals with mean age 51.90 ± 11.28 (81 cases and 163 controls matched by age, sex, and smoking habit). Also, the clusterization phenomenon was investigated stratifying the sample into two groups: (a) 34 patients with multiple losses (presenting two or more lost implants) and (b) 210 without multiple losses (up to one implant loss). Sociodemographic, clinical, and periodontal parameters were analyzed. The tagSNPs in the VDR gene were analyzed by real-time PCR. Univariate and multivariate analyses were performed (p < .05). RESULTS: Edentulism, number of implants installed, and Gingival, Plaque, and Calculus Indexes were associated with implant loss in the univariate analysis. After the multivariate analysis, the allele G of rs3782905 in the recessive model, together with number of installed implants and Gingival Index, was associated with implant failure. CONCLUSION: It is suggested that the allele G of rs3782905 in the recessive model may be a new genetic risk marker for dental implant loss in patients who lost two or more dental implants. In addition, number of implants installed and Gingival Index were also associated. Replication is mandatory to confirm these findings, due to the modest sample size of this work.

Association of clinical variables and polymorphisms in RANKL, RANK, and OPG genes with external apical root resorption.

OBJECTIVES: The aim of this study was to investigate the association of clinical variables and polymorphisms in the RANKL, RANK, and OPG genes with external apical root resorption (EARR). METHODS: The sample was composed of 338 unrelated patients of both sexes, average age 14.9 years (range 8-21) with Class II Division 1 malocclusion, orthodontically treated. Periapical radiographs of the maxillary central incisor with the longer root (reference tooth) were taken before treatment and 6 months after starting treatment. DNA was extracted from buccal epithelial cells with the use of 10 mol/L ammonium acetate and 1 mmol/L EDTA. The analysis of 42 polymorphisms in the RANKL, RANK, and OPG genes was performed by means of real-time polymerase chain reaction. Univariate and multivariate analyzes were performed to verify the association of clinical and genetic variables with EARR (P <0.05). RESULTS: The initial root length and patient age were associated with EARR. Considering the study of polymorphisms of RANKL, no significant association was found of genetic polymorphisms with EARR. For RANK polymorphisms, only rs12455775 was associated with EARR. Regarding OPG polymorphisms, an association of rs3102724, rs2875845, rs1032128, and rs3102728 with EARR was found. After multivariate analysis, the initial root length, rapid maxillary expansion, and rs3102724 of the OPG gene were associated with EARR. CONCLUSIONS: Longer roots of upper central incisors and rapid maxillary expansion, as well as allele A of the rs3102724 polymorphism of the OPG gene, were associated with EARR in the study population.

Clinical aspects and polymorphisms in the LTA, TNFA, LTB genes and association with dental implant loss.

BACKGROUND: This study shows the relationship between host factors and environmental factors in the influence of susceptibility to loss of dental implants. PURPOSE: The aim of this study was to investigate the association of clinical aspects and tag SNPs of the genes LTA, TNFA, and LTB with dental implant loss. MATERIALS AND METHODS: The subjects consisted of 244 patients, divided into two groups: control group (C)-163 individuals who did not lose any implants, being in function for at least 6 months; and study group (S)-81 individuals who had lost at least one implant. DNA was collected from saliva, and the genotypes were determined by real time PCR. Univariate and multivariate analysis were employed p < .05. RESULTS: After multivariate analysis, dental implant loss remained associated with the presence of teeth (p = .011), a larger amount of placed implants (p = .001), and allelle C of rs2009658 of the LTA gene (p = .006). For the other tag SNPs of these studied genes, there was no association between the groups C and S with dental implants loss. CONCLUSION: Presence of teeth, number of placed implants and allele C of rs2009658 of LTA gene were associated with implant loss.

Vitamin D Receptor Gene Polymorphisms and Environment Influencing the Impact on Survival in Hemodialysis Patients.

INTRODUCTION: The vitamin D-receptor axis is involved in multiple physiological functions and altered states such as hypertension, mineral metabolism disorders, and inflammation. These disturbances are major risk factors for progression to end-stage kidney disease and cardiovascular disease. In addition, changes in internal systemic environment could be influencing the impact of survival in patients with kidney disease. This study aimed to evaluate the impact of vitamin D receptor (VDR) polymorphisms on hemodialysis patients' survival. MATERIAL AND METHODS: A total of 122 hemodialysis patients and 120 healthy controls were compared for VDR gene polymorphism. Markers for full coverage in the VDR gene were selected and genotyped. The hemodialysis patients were followed until death event, which was considered the primary endpoint for the survival analysis. RESULTS: Two tag SNPs (rs10875695 and rs11168293) showed significant differences between the hemodialysis and healthy patients. In survival analysis, the CC genotype for rs2248098, compared to the TT genotype, was associated with a worse mortality rate. After adjustments for age, sex, diabetes mellitus, and cardiovascular disease, the genotype CC (rs2248098) was associated with a higher risk of mortality in a multivariable analysis. CONCLUSIONS: Polymorphisms specific to patients with kidney disease could be influencing different conditions associated with mortality. Thus, these genetic markers, rs2248098 for example, would act in a specific time in the history of kidney disease and would bring different results of patient survival outcomes.

Polymorphisms in Nonamelogenin Enamel Matrix Genes Are Associated with Dental Fluorosis.

The aim of this study was to evaluate whether genetic polymorphisms in AMELX, AMBN, ENAM, TFIP11, and TUFT1 genes are associated with dental fluorosis (DF). A total of 1,017 children from 2 Brazilian cohorts were evaluated. These populations lived in cities with fluoridation of public water supplies. DF was assessed in erupted permanent teeth using the modified Dean index. The polymorphisms rs946252, rs12640848, rs4694075, rs5997096, and rs4970957 were analyzed by real-time PCR from genomic DNA. Associations between DF, genotype, and allele distribution were evaluated using the χ2 test, with an alpha of 5%. The polymorphisms rs4694075, rs5997096, and rs4970957 in AMBN, TFIP11, and TUFT1 were associated with DF (p < 0.05). In conclusion, enamel matrix genes are associated with DF.

Expression of MMP-13 in human temporomandibular joint disc derangement and osteoarthritis.

OBJECTIVE: MMP-13 performs digestion of collagen, which is a primary component of the temporomandibular joint (TMJ) articular disc. This study evaluated the expression of MMP-13 in patients with anterior disc displacement with (ADDwR) and without reduction (ADDwoR), and in the presence of TMJ osteoarthrosis. METHODS: Thirty-nine human temporomandibular joint disc samples were collected and divided in two ways: ADDwR (21 samples), ADDwoR (10 samples), and a control group (8 samples); and with osteoarthrosis (10 samples) and without osteoarthrosis (29 samples). Immunostaining of the TMJ discs was statistically compared between the groups. RESULTS: There was no statistically significant difference for the area of MMP-13 immunostaining between the control group, ADDwR, and ADDwoR, nor between groups with and without osteoarthrosis. CONCLUSION: This study suggests MMP-13 is not significantly involved in collagen degradation in human TMJ disc displacement or osteoarthrosis.

Types of External Root Resorption of Replanted Teeth: Analysis of the Clinical Aspects and of Interleukin-4 Gene Polymorphisms Involvement.

INTRODUCTION: The absence or presence of root resorption on the surface of a replanted tooth indicates an immune-inflammatory reaction. Recent research even suggests the participation of host predominant immunologic profile on types of resorptions detected on the root surface. Because interleukin 4 (IL-4) is an important anti-inflammatory cytokine, this study aimed to investigate the association of clinical variables and polymorphisms in IL4 with types of resorption of replanted teeth after 1 year of follow-up. METHODS: One hundred twenty-seven avulsed teeth that were replanted were selected. Periapical radiographs were taken after replantation and for 1 year to detect the types of root resorption. Real-time polymerase chain reaction was used to genotype IL4 polymorphisms. The χ2 and Z tests were performed to verify the association of clinical and genetic variables with the outcomes of replanted teeth (P < .05). RESULTS: An association was observed of extra-alveolar time, storage medium, and development of the root (P < .05), but not of IL4 polymorphisms, with the outcomes of replanted teeth (P > .05). CONCLUSIONS: Extraoral time, storage medium, and development of the root, but not IL4 polymorphisms, may influence the types of resorption of avulsed and replanted teeth in the first year after trauma.

Genes Involved in the Enamel Development Are Associated with Calcium and Phosphorus Level in Saliva.

Saliva components play a crucial role in the integrity of the dental enamel and in caries susceptibility. The saliva characteristics are controlled by many factors, including genetic factors. Therefore, this study aimed to evaluate the association between the genetic variations in genes expressed in enamel development with calcium and phosphorus levels in saliva. We collected 276 unrelated 12-year-old children from private and public schools. Saliva was collected for DNA extraction from oral cells and for measurement of calcium and phosphorus. Inductively coupled plasma-mass spectrometry determined calcium and phosphorus levels in whole saliva. Fifteen genetic variations in 9 genes were analyzed. The genotype was determined by real-time polymerase chain reactions. Data were analyzed using Plink with an alpha of 5%. Genetic variations in AMELX, AMNB and ESRRB were associated with the calcium level in saliva (p < 0.05). A borderline association was observed in ENAM allele distribution shown with phosphate level in saliva (p = 0.049). In conclusion, our results are the first to report that genetic variations contribute to calcium and phosphorus levels in saliva.

Interleukin-6 expression in disc derangement of human temporomandibular joint and association with osteoarthrosis.

The inflammatory process is a coordinated response that protects host after infection or trauma, involving several molecular reactions. Once the inflammation is closely linked to the process of destruction of the temporomandibular joint, this study aims to examine, by immunohistochemistry, the expression of interleukin-6 (IL-6), an important inflammatory marker, in temporomandibular articular discs of patients with anterior disc displacement with (ADDwR) and without reduction (ADDwoR) and its association with osteoarthrosis (OA). Thirty-eight (n = 38) articular discs were divided into two cutoffs: 1) analysis 1: 4 control (acute pathology), 17 ADDwR, 17 ADDwoR; and 2) analysis 2: without OA (n = 21) and with OA (n = 17). The area of immunostaining was compared statistically between groups (p < 0.05). In the disc samples, no significant differences were observed between the groups ADDwR and ADDwoR, and with and without OA, in respect to the expression of IL-6 by immunohistochemical examination. Future studies should be conducted with a larger sample size, which could clarify the association of the inflammatory mediator IL-6 with temporomandibular joint dysfunction.

The use of a custom-made mouthguard stabilizes the electromyographic activity of the masticatory muscles among Karate-Do athletes.

AIMS: To analyze and compare the electromyographic activity of the temporal (anterior portion) and masseter muscles among Karate-Do athletes before and after training, with and without the use of a mouthguard. METHODS: Twenty athletes (14 males and 6 females) with a mean age of 23.7 ± 7.5 years participated. They had surface electromyography recordings taken of their bilateral temporal and masseter muscles before and after training under the following conditions: no mouthguard, with a ready-made mouthguard, and with a custom-made mouthguard. Activity was examined at mandibular rest, while clenching, and at maximum voluntary contraction. The data were normalized using the mean maximum voluntary contraction. RESULTS: The right (p = 0.005) and left (p = 0.015) temporal muscles showed significantly lower electromyographic activity with a custom-made mouthguard compared with no mouthguard after training while clenching. The electromyographic activity of the temporal and masseter muscles did not show significant differences when tested at mandibular rest and while clenching before or after training with a custom-made mouthguard (p > 0.05). CONCLUSION: The use of a custom-made mouthguard preserved participants' electromyographic profiles before and after training; thus, they allow for stable muscle activity during the training of Karate-Do athletes.

Host and clinical aspects in patients with benign migratory glossitis.

OBJECTIVE: Investigate the association of clinical, cytological and genetic characteristics with benign migratory glossitis (BMG). STUDY DESIGN: Sample consisted of 175 patients, 44 with BMG and 131 control patients. Clinical examination and DMFT index were assessed. Cytological evaluation determined cell morphology and morphometry. Genetic evaluation was performed by analysing IL6 polymorphisms by real-time PCR. Univariate and multivariate analyses were performed (p<0.05). RESULTS: There was a higher level of anxiety, DMFT score and a prevalence of fissured tongue in BMG group. A high mean nuclear/cytoplasmic area ratio was observed in patients with BMG. There was predominance of Papanicolaou class II I BMG group. IL6 allele G rs2069843 polymorphism was associated with BMG in the dominant model. In multivariate analysis, DMFT and anxiety scale remained associated with BMG.