RESUMO
El desgaste natural de los dientes ocurre dependiendo de factores como: calidad de la estructura dental, calidad de la saliva, biotipo facial que determina la fuerza de mordida; de acuerdo a estos factores locales bucales se va envejeciendo la dentadura. Pero los deportistas presentan un patrón de desgaste mayor y continuo debido al tipo de deporte que practican, las horas de entrenamiento, el consumo de bebidas con pH ácido, el cepillado dental vigoroso; todos estos factores pueden conducirlos a que desarrollen lesiones no cariosas (AU)
The natural wear of the teeth occurs depending on factors such as: quality of the dental structure, quality of the saliva, facial biotype that determines the bite force, according to these local oral factors, the teeth age. But in athletes they present a pattern of greater and continuous wear due to the type of sport they practice, the hours of training, the consumption of drinks with an acidic pH, vigorous tooth brushing; all these factors can lead them to develop non-carious lesions (AU)
Assuntos
Humanos , Masculino , Feminino , Dente/fisiopatologia , Envelhecimento/fisiologia , Senilidade Prematura , Abrasão Dentária/fisiopatologia , Erosão Dentária/fisiopatologia , Fatores de Risco , Atrito Dentário/fisiopatologiaRESUMO
BACKGROUND: The aim of this study was to measure the effect of simulating two different loads on maxillary incisors displaying eight morphological types of non-carious cervical lesions, unrestored and restored with an adhesive restoration, by quantifying the stress distributions generated using finite element analysis. METHODS: Virtual models of maxillary incisors were generated using the CAD software (RhinoCeros). After composing virtual dental and supporting structures with and without non-carious cervical lesions, each model was meshed using a control mesh device (ANSYS Finite Element Analysis Software). All of the virtual models were subjected to two load types, oblique load and vertical load, to simulate occlusal forces of 100 N each. Comparisons were made between simulated teeth with non-carious cervical lesions, with and without composite resin restorations, and a simulated sound tooth. Data summarizing the stress distributions were obtained in MPa using von Mises criteria. RESULTS: Oblique loading on simulated non-carious cervical lesions resulted in greater stress concentration compared with vertical loading, and non-carious cervical lesions with acute angles displayed higher stress concentrations at the depth of the lesion. Restoring the lesions with an adhesive restoration, such as composite resin, appeared to overcome this stress concentration. CONCLUSIONS: Restoring NCCLs with adhesive restorative materials, such as a nanohybrid composite resin, appears to recover the biomechanical behaviour similar to sound teeth.
Assuntos
Força de Mordida , Análise do Estresse Dentário/métodos , Incisivo/fisiopatologia , Abrasão Dentária/fisiopatologia , Colo do Dente , Fenômenos Biomecânicos/fisiologia , Resinas Compostas/uso terapêutico , Materiais Dentários/uso terapêutico , Análise de Elementos Finitos , Humanos , Maxila , Resistência à Tração , Abrasão Dentária/patologia , Abrasão Dentária/terapiaRESUMO
This review discusses the role of matrix metalloproteinases (MMPs) in the development of dentin erosion and the protective effects of MMP inhibitors, based on recent evidence from in vitro and in situ studies. MMPs are present in both dentin and saliva and play an important role in dentin erosion progression. Enzymatic removal of the organic matrix by MMPs increases the demineralization process, since the demineralized organic matrix has been shown to hamper ionic diffusion after an acidic challenge. Recent evidence from in vitro and in situ studies has shown a protective role of MMP inhibitors against dentin erosion and erosion plus abrasion. The inhibitors tested were green tea and its active epigallocatechin-gallate (EGCG), ferrous sulfate, and chlorhexidine. They have been tested in dentifrices, solutions, and gels. The latter led to a more pronounced protective effect against dentin erosion and erosion plus abrasion. The protection was long-lasting and could be observed after up to 10 days of severe erosive and erosive-plus-abrasive challenges in situ. Thus, the use of MMP inhibitors has emerged as an important preventive tool against dentin erosion. Clinical studies should be conducted to confirm the results obtained and to give support to the establishment of clinical protocols of use.
Assuntos
Dentifrícios/farmacologia , Dentina/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz/farmacologia , Metaloproteinases da Matriz/metabolismo , Abrasão Dentária/prevenção & controle , Erosão Dentária/prevenção & controle , Bebidas Gaseificadas/efeitos adversos , Dentina/enzimologia , Humanos , Inibidores de Metaloproteinases de Matriz/uso terapêutico , Abrasão Dentária/etiologia , Abrasão Dentária/fisiopatologia , Erosão Dentária/etiologia , Erosão Dentária/fisiopatologiaRESUMO
AIM: The aim of this study was to investigate changes in interocclusal distance (IOD) during pronunciation of /m/ and /s/ sounds in Brazilian Portuguese, in patients presenting dental wear due to bruxism, before and after placement of a stabilization appliance and restorative treatment. METHODS: Subjects were divided into a control group of 19 patients with no dental wear and an experimental group of 18 patients presenting dental wear on anterior teeth due to bruxism. A stabilization appliance was placed in each patient in the experimental group and anterior teeth were restored. A magnetic jaw-tracking device measured the interocclusal distance during pronunciation of /m/ and /s/ phonemes. Interocclusal distance for the experimental group was evaluated one week before and again immediately before the appliance was inserted and 24 hours, 7 days, 1 month and 2 months after appliance insertion. The same evaluation was performed 7 days and 1 month after restorative treatment. In the control group, the measurements were carried out at the same intervals. RESULTS: Comparison between groups revealed a significant difference (P<0.05) in interocclusal distance for the /m/ sound at all evaluation intervals. No differences were found before and after appliance insertion and restorative treatment with either phoneme. CONCLUSION: Stabilization appliance therapy and restorative treatment of subjects with dental wear did not change the interocclusal distance during speech of /m/ and /s/ sounds in the Brazilian Portuguese language, however, when compared with normal subjects, the IOD values were higher for the dental wear group during pronunciation of the /m/ sound.
Assuntos
Oclusão Dentária , Desgaste de Restauração Dentária , Restauração Dentária Temporária , Fala/fisiologia , Abrasão Dentária/fisiopatologia , Resinas Acrílicas , Adulto , Brasil , Bruxismo/complicações , Bruxismo/reabilitação , Feminino , Seguimentos , Humanos , Idioma , Masculino , Maxila , Pessoa de Meia-Idade , Fonética , Testes de Articulação da Fala , Abrasão Dentária/etiologiaRESUMO
This study described changes in mandibular movements during pronunciation of /m/ and /s/ sounds in Portuguese, in patients presenting dental wear before and after appliance insertion and tooth reconstruction. Subjects were divided into a control group of dentate patients and an experimental group of patients with incisal tooth wear due to bruxism. A magnetic jaw tracking device measured the jaw opening, and translations to left and right sides of the mandible during pronunciation of phonemes. Evaluations were carried out 1 week and immediately before appliance insertion; 24 h, 7, 30 and 60 days after appliance insertion; and 1 week and 1 month after tooth reconstruction. Data were submitted to two-way ANOVA, Mann-Whitney and Friedman tests (p<0.05). Jaw opening was different (p<0.05) for both sounds in all periods. The anteroposterior amplitude for /s/ showed differences immediately before and 1 month after appliance insertion (p<0.05). Lateral amplitude for the right side showed differences between groups after appliance insertion for /s/, and 1 and 2 months after appliance insertion for the /m/ (p<0.05). Volunteers with anterior tooth wear had a wider opening movement, and the movements during speech of /m/ and /s/ sounds were not changed after appliance insertion and reconstruction of teeth.
Assuntos
Restauração Dentária Permanente/métodos , Mandíbula/fisiopatologia , Placas Oclusais , Fala/fisiologia , Abrasão Dentária/fisiopatologia , Condicionamento Ácido do Dente , Adolescente , Adulto , Bis-Fenol A-Glicidil Metacrilato/química , Bruxismo/complicações , Bruxismo/fisiopatologia , Resinas Compostas/química , Materiais Dentários/química , Adesivos Dentinários/química , Feminino , Seguimentos , Humanos , Incisivo/patologia , Idioma , Masculino , Pessoa de Meia-Idade , Movimento , Fonética , Abrasão Dentária/terapia , Adulto JovemRESUMO
This study described changes in mandibular movements during pronunciation of /m/ and /s/ sounds in Portuguese, in patients presenting dental wear before and after appliance insertion and tooth reconstruction. Subjects were divided into a control group of dentate patients and an experimental group of patients with incisal tooth wear due to bruxism. A magnetic jaw tracking device measured the jaw opening, and translations to left and right sides of the mandible during pronunciation of phonemes. Evaluations were carried out 1 week and immediately before appliance insertion; 24 h, 7, 30 and 60 days after appliance insertion; and 1 week and 1 month after tooth reconstruction. Data were submitted to two-way ANOVA, Mann-Whitney and Friedman tests (p<0.05). Jaw opening was different (p<0.05) for both sounds in all periods. The anteroposterior amplitude for /s/ showed differences immediately before and 1 month after appliance insertion (p<0.05). Lateral amplitude for the right side showed differences between groups after appliance insertion for /s/, and 1 and 2 months after appliance insertion for the /m/ (p<0.05). Volunteers with anterior tooth wear had a wider opening movement, and the movements during speech of /m/ and /s/ sounds were not changed after appliance insertion and reconstruction of teeth.
O objetivo deste estudo foi verificar alterações nos movimentos mandibulares durante a pronúncia dos fonemas /m/ e /s/ da língua portuguesa, em pacientes com desgaste dental incisal antes a após a instalação de placas interoclusais e restauração dos dentes. Os voluntários foram divididos em grupo controle, composto por pacientes dentados, e grupo experimental composto por pacientes com desgastes incisais devido ao bruxismo. Desvios laterais para direita e esquerda, e de abertura foram mensurados por meio do método eletromagnético do registro do traçado mandibular durante a pronúncia dos fonemas /m/ e /s/. As avaliações foram realizadas 1 semana e imediatamente antes da instalação de placas interoclusais; 24 h, 7, 30 e 60 dias após a instalação das mesmas, e 1 semana e 1 mês após a restauração dos dentes. Os resultados foram submetidos à ANOVA a dois critérios e testes de Mann-Whitney e Friedman t (p<0,05). O movimento de abertura foi diferente (p<0,05) para ambos os sons em todos os períodos avaliados. Houve diferença (p<0,05) na amplitude anteroposterior durante pronúncia do som /s/ imediatamente antes e 1 mês após a instalação da placa. O desvio lateral para o lado direito apresentou diferença (p<0,05) entre grupos durante a pronúncia do /s/ em todos os períodos após a inserção da placa, e 1 mês e 2 meses após a inserção da mesma para o som /m/. Pacientes com desgaste dental anterior apresentaram amplo movimento de abertura, e movimentos mandibulares durante a pronúncia dos sons /m/ e /s/ não foram alterados após a instalação de placa e restauração dos dentes.
Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Restauração Dentária Permanente/métodos , Mandíbula/fisiopatologia , Placas Oclusais , Fala/fisiologia , Abrasão Dentária/fisiopatologia , Condicionamento Ácido do Dente , Bis-Fenol A-Glicidil Metacrilato/química , Bruxismo/complicações , Bruxismo/fisiopatologia , Resinas Compostas/química , Materiais Dentários/química , Adesivos Dentinários/química , Seguimentos , Incisivo/patologia , Idioma , Movimento , Fonética , Abrasão Dentária/terapia , Adulto JovemRESUMO
The effect of salivary exposure time on the abrasive wear of acid-eroded dentine was evaluated in situ. One-hundred and twenty bovine root dentine slabs were randomly assigned into six groups (A-F) and placed in intraoral palatal devices, which were worn by 10 volunteers for 4 d. On the first day, no erosive/abrasive procedures were carried out. On the following 3 d, erosive challenges were performed extraorally, two times per day, by immersing the device for 90 s in a soft drink. Subsequently, the group A specimens were immediately brushed (40 strokes), and the others were brushed after the following times: B, 20 min; C, 40 min; and D, 60 min. Group E specimens were only acid-eroded and those of group F were only brushed. Dentine wear was measured with a profilometer. anova and Dunnett's test showed that groups A-D did not differ statistically from the control group E but differed from the control group F. The lowest mean value was found for group F. Regression analysis was unable to show salivary effect on dentine wear reduction. The data suggest that the exposure time of saliva of up to 60 min has no effect on reducing the eroded dentine wear by toothbrushing.
Assuntos
Dentina/patologia , Saliva/fisiologia , Abrasão Dentária/etiologia , Erosão Dentária/etiologia , Raiz Dentária/patologia , Adulto , Análise de Variância , Animais , Bebidas Gaseificadas/efeitos adversos , Bovinos , Dentina/fisiopatologia , Feminino , Dureza , Humanos , Modelos Lineares , Masculino , Fatores de Tempo , Abrasão Dentária/fisiopatologia , Erosão Dentária/fisiopatologia , Raiz Dentária/fisiopatologia , Escovação Dentária/efeitos adversosRESUMO
This work discusses the effect of enamel anisotropy in the stress concentration at the cement-enamel junction (CEJ), a probable cause of fracture in enamel leading to abfraction. Usual simplifications when developing computer models in dentistry are to consider enamel isotropic, or that the direction of the prisms is orthogonal to either the dentine-enamel interface or the tooth outer surface. In this paper, a more refined model for the material behavior is described, based on laboratory observation and on the work of Fernandes and Chevitarese. The material description is used in a two-dimensional (2D) finite element model of the first upper premolar, and the analysis is performed for two different situations: vertical loads, typical of normal mastication and horizontal loads, dominant in bruxism. The analyses were performed using a unit load, which under the hypothesis of linear response of the tooth, allows the combinations described in the text to simulate different functional and parafunctional loads. The results indicate that a realistic enamel description in terms of mechanical properties and spatial distribution of its prisms alters significantly the resulting stress distribution. For all cases included in this study, the detailed description of prism orientation and resulting anisotropy led to improved response in terms of stress distribution, even when loading was horizontal.
Assuntos
Dente Pré-Molar/fisiopatologia , Esmalte Dentário/fisiopatologia , Análise do Estresse Dentário/métodos , Modelos Biológicos , Abrasão Dentária/fisiopatologia , Colo do Dente/fisiopatologia , Anisotropia , Força de Mordida , Bruxismo/complicações , Bruxismo/fisiopatologia , Durapatita , Elasticidade , Análise de Elementos Finitos , Humanos , Sensibilidade e Especificidade , Estresse Mecânico , Resistência à Tração , Abrasão Dentária/etiologia , Atrito Dentário/fisiopatologia , Suporte de CargaRESUMO
Rett syndrome (RS) is a neurodegenerative disorder characterized by developmental arrest of parts of the brain. It is an X chromosome-linked condition which affects females almost exclusively. Recent reports have been generated concerning the multidisciplinary management of individuals exhibiting Rett syndrome. The aim of the present report was to provide an update on the oral manifestations of the disorder. We evaluated the general and oral characteristics of RS in 13 female patients. The most frequent manifestations were stereotyped hand movements and bruxism. The treatment we carried out included the use of biteplanes and acupuncture.
Assuntos
Doenças da Boca/patologia , Síndrome de Rett/patologia , Terapia por Acupuntura , Adolescente , Ansiedade/fisiopatologia , Bruxismo/fisiopatologia , Criança , Pré-Escolar , Assistência Odontológica para Crianças , Assistência Odontológica para a Pessoa com Deficiência , Feminino , Mãos/fisiopatologia , Humanos , Doenças da Boca/terapia , Transtornos dos Movimentos/fisiopatologia , Placas Oclusais , Síndrome de Rett/fisiopatologia , Síndrome de Rett/terapia , Abrasão Dentária/fisiopatologiaRESUMO
Dental microwear researchers consider exogenous grit or dust to be an important cause of microscopic wear on primate teeth. No study to date has examined the accumulation of such abrasives on foods eaten by primates in the forest. This investigation introduces a method to collect dust at various heights in the canopy. Results from dust collection studies conducted at the primate research stations at Ketambe in Indonesia, and Hacienda La Pacifica in Costa Rica indicate that 1) grit collects throughout the canopy in both open country and tropical rain forest environments; and 2) the sizes and concentrations of dust particles accumulated over a fixed period of time differ depending on site location and season of investigation. These results may hold important implications for the interpretation of microwear on primate teeth.
Assuntos
Dieta , Poeira , Primatas , Abrasão Dentária/etiologia , Árvores , Alouatta , Análise de Variância , Animais , Cercopithecidae , Costa Rica , Hylobates , Incisivo , Indonésia , Macaca fascicularis , Pongo pygmaeus , Abrasão Dentária/fisiopatologiaRESUMO
The present study of 2,387 recordings of 12 anterior teeth in 53 patients indicates that the incisal edge is the optimal placement-site for the electric pulp tester to determine the lowest response threshold. The results show significant individual variations in the lowest threshold responses of the cervical-third, middle-third, incisal one-third, and incisal edge sites on a tooth, with a confidence level of 99%, according to the analysis of variance. The maxillary teeth gave a higher response threshold than the mandibular teeth and different types of teeth (canines and incisors) had statistically significant different response thresholds. The application of the electric pulp tester to the incisal-edge region with exposed dentin produced the most significant decrease in the threshold response.