14 research outputs found
Dental wear caused by association between bruxism and gastroesophageal reflux disease: a rehabilitation report
Bruxism is a pathological activity of the stomatognathic system that involves tooth grinding and clenching during parafunctional jaw movements. Clinical signs of bruxism are mostly related to dental wear and muscular and joint discomforts, but a large number of etiological factors can be listed, as local, systemic, psychological and hereditary factors. The association between bruxism, feeding and smoking habits and digestive disorders may lead to serious consequences to dental and related structures, involving dental alterations (wear, fractures and cracks), periodontal signs (gingival recession and tooth mobility) and muscle-joint sensivity, demanding a multidisciplinary treatment plan. This paper presents a case report in which bruxism associated with acid feeding, smoking habit and episodes of gastric reflow caused severe tooth wear and great muscular discomfort with daily headache episodes. From the diagnosis, a multidisciplinary treatment plan was established. The initial treatment approach consisted of medical follow up with counseling on diet and smoking habits and management of the gastric disorders. This was followed by the installation of an interocclusal acrylic device in centric relation of occlusion (CRO) for reestablishment of the occlusal stability, vertical dimension of occlusion, anterior guides and return to normal muscle activity (90-day use approximately). After remission of initial symptoms, oral rehabilitation was implemented in CRO by means of full resin composite restorations and new interocclusal device for protection of restorations. Satisfactory esthetics, improved function and occlusal stability were obtained after oral rehabilitation. The patient has attended annual follow-ups for the past 2 years. The multidisciplinary treatment seems to be the key for a successful rehabilitation of severe cases of dental wear involving the association of different health disorders
Radiodensity evaluation of dental impression materials in comparison to tooth structures
In the most recent decades, several developments have been made on impression materials' composition, but there are very few radiodensity studies in the literature. It is expected that an acceptable degree of radiodensity would enable the detection of small fragments left inside gingival sulcus or root canals. OBJECTIVE: The aim of this study was to determine the radiodensity of different impression materials, and to compare them to human and bovine enamel and dentin. MATERIAL AND METHODS: Twenty-five impression materials, from 5 classes, were studied: addition and condensation silicones, polyether, polysulfides and alginates. Five 1-mm-thick samples of each material and tooth structure were produced. Each sample was evaluated 3 times (N=15), being exposed to x-ray over a phosphor plate of Digora digital system, and radiodensity was obtained by the software Digora for Windows 2.5 Rev 0. An aluminum stepwedge served as a control. Data were subjected to Kruskal-Wallis and Dunn's method (α=0.05). RESULTS: Different materials and respective classes had a different behavior with respect to radiodensity. Polysulfides showed high values of radiodensity, comparable to human enamel (p>0.05), but not to bovine enamel (
Influence of powder/liquid ratio on the radiodensity and diametral tensile strength of glass ionomer cements
Radiodensity evaluation of dental impression materials in comparison to tooth structures
Effect of different acupuncture protocols on temporomandibular disorders
Este trabalho teve por objetivo avaliar os efeitos da acupuntura em dois diferentes grupos de pacientes portadores de Disfunções Temporomandibulares (DTM), um deles com DTM de caracterÃstica apenas muscular (MUSC), e o outro com DTM muscular associada a desordem articular (ART). Participaram dessa pesquisa 68 pacientes, 32 no grupo MUSC e 36 no grupo ART. Os pacientes de cada grupo foram aleatoriamente subdivididos em dois grupos, que receberam diferentes tratamentos por acupuntura. Um grupo foi tratado com pontos próximos ao local da dor (VG20, VB20, TA21, E6 e E7), e o outro, com pontos à distância (IG4 e YinTang). Foram 6 sessões semanais, cada uma com duração de 20 minutos. Os pacientes foram avaliados por meio de escala visual analógica (VAS), limiar de dor à pressão por algômetro, sensibilidade dolorosa à palpação digital, extensão de movimentos mandibulares, questionário para medir o impacto da dor na qualidade de vida (OHIP-14), questionário de qualidade do sono (SAQ) e questionário para avaliar a percepção dos sinais e sintomas pelo paciente (ProDTMmulti). As avaliações foram feitas em 4 momentos diferentes, o inicial, no primeiro contato com o paciente após o perÃodo de triagem, o controle, após 4 semanas sem qualquer intervenção terapêutica, o final, após 6 sessões semanais de acupuntura, e o de acompanhamento, 4 semana após o fim do tratamento, sem que nenhum intervenção fosse feita. Os resultados demonstraram que as melhorias estatisticamente significativas para os grupos experimentais foram observadas de maneira generalizada para a avaliação subjetiva da dor, em que todos os grupos de comportaram de maneira semelhante, apesar de os melhores resultados terem sido observados em ART-PD. Em todos os outros parâmetros de avaliação foi possÃvel observar aspectos de melhoria dos grupos com significância estatÃstica (p<0,05), mas não de maneira generalizada como na VAS. Parâmetros objetivos, como extensão de movimentos mandibulares e algometria, mostraram uma tendência para melhoria, embora sem significância estatÃstica para todos os grupos. A acupuntura foi um tratamento considerado eficiente no controle da dor e dos outros aspectos avaliados em pacientes com DTM muscular associada ou não a alterações articulares.This study aimed to evaluate the effect of acupuncture treatment in two diferent types of temporo-mandibular disorder (TMD) pacients: muscular TMD (MUSC) and a muscular plus articular TMD (ART). Out of 68 patientes, 32 were classified to the MUSC group and the other 36 ones for the ART group. Patientes of each group were randomly assigned into two subgroups according to type of practiced acupuncture. One subgroup were treated with local acupuncture, next (PL) to the pain location (VG20, VB20, TA21, E6 e E7), and the other one were treated with needles inserted distant (PD) to the pain location (IG4 e YinTang). Six weekly 20min treatment sections were performed. The patients were evaluated according to Visual Analogic Scale (VAS), pressure pain thresold by algometer, digital pressure pain sensation, mandibular movements extension, quality of life questionaire (OHIP-14), sleep quality questionaire (SAQ), and signals and simptoms questionaire (ProDTMmulti). Evaluations were performed at for different moments: initially, at the first meeting; control, four weeks after the initial meeting; end, after six acupunture meetings; and follow-up, four weeks after treatment end, without any additional intervention. Results showed that statistical significant better observations for subjective pain evaluation were noted for all groups, in spite of the best results were noted in ART-PD. According to all evaluation methods it was possible to note better results for all groups (p<0,05), but this was not so noticiable as on VAS evaluation. Direct objective parameters, i.e., mandibular movements extension or algomenter measurements, showed a tendecy for better results, but no statistical significant results were found. Acupuncture could be considered an effective treament option for pain relief and also for the other evaluated aspects for patients with muscular TMD with or without articular association
Influência do tipo de pôntico, número de pilares e tipo de aplicação de carga na distribuição das tensões em prótese fixa em cantilever análise por elementos finitos
Cantilever fixed prosthodontics are satisfactory rehabilitation alternatives
when osseointegrated implants are not indicated, which justifies the important
knownledgment with respect to a correct indication and technical procedures. The
aim of this study was to evaluate the stress distribution on support dental
structures and prosthesis framework by finite elements method. The pontic
anatomy (premolar or molar), type and number of abutments (one or two, single or
bilateral, anteriorly or posteriorly faced) e occlusal load (premature contact or
normal occlusion). A real model composed by a canine, first and second
premolars, first, second and third molars was employed for the creation of the 2D
mathematical models, simulating all the involved dental and prosthetic structures
and studying stress distribution by finite elements method under normal occlusal
load or premature contact near or distant from the primary prosthesis conector.
Five percent of physiologic masticatory load was used in the simulation. The
plotted images were qualitatively analyzed. In the quantitative analysis stress
values were collected at two selected lines in the models, line A, created 2mm
above cortical bone at the edentulous space, and line B, which was located at the
center of prosthesis conectors. The regions with the most pronouncing stress
concentrations were the cortical bone, roots of abutment teeth and prosthesis
conectors. Stress were lower and better distributed on conventional fixed
prosthesis, irrespective of the type of pontic. The models, for both premolar or
molar pontics, under premature contact load condition showed the most
unfavorable stress conditions, principally when it occurred distant from the primary
conector. Within the limitations of this study it is possible to conclude that
conventional fixed prosthesis show stress distribution in a more favorable condition
than cantilever prosthesis. The most extensive pontic (molar) results in more
unfavorable and greater stress at adjacent structures. The inclusion of a second
abutment is more favorable to support dental structures and prosthesis framework
when premature contact load condition takes place.Coordenação de Aperfeiçoamento de Pessoal de NÃvel SuperiorMestre em OdontologiaPróteses fixas em cantilever são alternativas reabilitadoras satisfatórias em
casos em que os implantes osseointegrados são contra-indicados, o que justifica a
importância de se conhecer seu comportamento mecânico para conduzir sua
indicação e os cuidados que devem ser associados a esse procedimento. O
objetivo deste trabalho foi avaliar a distribuição das tensões nas estruturas de
suporte e protéticas em próteses fixas utilizando o método de elementos finitos.
Foram comparados anatomia do pôntico (molar e pré-molar), tipos e número de
pilares (um ou dois, uni ou bilaterais, voltados para anterior ou posterior do
pôntico) e tipo de carregamento oclusal (contato prematuro ou oclusão normal).
Um modelo real composto por canino, primeiro e segundo pré-molares e primeiro,
segundo e terceiro molares foi utilizado para a confecção dos modelos
matemáticos bidimensionais de próteses fixas simulando todas as estruturas
envolvidas, a fim de avaliar a distribuição das tensões pelo método de elementos
finitos sob carga oclusal normal ou em contato prematuro em ponto próximo ou
distante do conector primário da prótese. Foram utilizados 5% da carga
mastigatória fisiológica. As imagens plotadas foram analisadas qualitativamente.
Para análise quantitativa, foram traçadas duas linhas em cada modelo, linha A,
localizada a 2mm da cortical óssea do espaço edêntulo, e linha B, na parte média
dos conectores das próteses. As regiões onde houve maior concentração das
tensões em todos os grupos foram a cortical óssea e estrutura radicular dos
dentes pilares e os conectores das próteses. As tensões foram menores e melhor
distribuÃdas na prótese fixa convencional, independente da anatomia do pôntico.
Os modelos em contato prematuro apresentaram os resultados mais
desfavoráveis, sendo o contato prematuro no ponto mais distante do conector
primário o mais danoso, tanto nos modelos com pôntico em pré-molar quanto em
molar. Diante das limitações deste estudo, pode-se concluir que as próteses fixas
convencionais possuem distribuição mais favorável que as próteses com pôntico
em cantilever. O pôntico mais extenso (molar) faz com que as tensões nas estruturas adjacentes sejam maiores e mais desfavoráveis. A adição de segundo
dente como pilar foi mais favorável a distribuição de tensões nas estruturas de
suporte e protéticas em casos de contato prematuro
Mechanical and acid root treatment on periodontally affected human teeth - A scanning electronic microscopy
Aim: To evaluate the root topography of human teeth affected by
periodontitis, after different root surface treatments. Methods:
Forty-two periodontally affected single-rooted human teeth were
selected and randomly divided into 7 groups (n=6): Cont- control group,
which received no treatment; Sca- root surface scaling and root
planning with curettes; ScaPh- Sca followed by 37% phosphoric acid gel
etching for 15 s; ScaEdta- Sca followed by 24% EDTA gel pH 7 for 1 min;
ScaCi- Sca followed by 30% citric acid pH 1.6 for 5 min; ScaTe- Sca
followed by - mixture obtained by 500 mg tetracycline capsule dissolved
in saline solution for 3 min; ScaTeg- Sca followed by 0.2 g/mL
tetracycline gel pH 1.8 for 1 min. The specimens were analyzed by
scanning electronic microscopy to verify the presence of calculus,
demineralization level and residues of the product. Results: Calculus
deposits were found in all control specimens. ScaEdta, ScaCi and ScaTeg
removed completely calculus deposits and resulted in adequate
demineralization without smear layer and smear plug on root surface.
ScaTe produced great tetracycline residues with several
demineralization areas on root dentin surface. Conclusions: ScaEdta,
ScaCi and ScaTeg produced clean root surfaces associated with regular
dentin demineralization
Mechanical and acid root treatment on periodontally affected human teeth - a scanning electronic microscopy
evaluate the root topography of human teeth affected by periodontitis, after different root surface treatments. Methods: Forty-two periodontally affected single-rooted human teeth were selected and randomly divided into 7 groups (n=6): Cont- control group, which received no treatment; Sca- root surface scaling and root planning with curettes; ScaPh- Sca followed by 37% phosphoric acid gel etching for 15 s; ScaEdta- Sca followed by 24% EDTA gel pH 7 for 1 min; ScaCi- Sca followed by 30% citric acid pH 1.6 for 5 min; ScaTe- Sca followed by mixture obtained by 500 mg tetracycline capsule dissolved in saline solution for 3 min; ScaTeg- Sca followed by 0.2 g/mL tetracycline gel pH 1.8 for 1 min. The specimens were analyzed by scanning electronic microscopy to verify the presence of calculus, demineralization level and residues of the product. Results: Calculus deposits were found in all control specimens. ScaEdta, ScaCi and ScaTeg removed completely calculus deposits and resulted in adequate demineralization without smear layer and smear plug on root surface. ScaTe produced great tetracycline residues with several demineralization areas on root dentin surface. Conclusions: ScaEdta, ScaCi and ScaTeg produced clean root surfaces associated with regular dentin demineralization
Effect of blood contamination during adhesive restorative procedures on dentin-resin cement shear bond strength
The aim of this study was to evaluate the effect of dentin blood
contamination during different steps of the restorative procedure on
resin cement shear bond strength to dentin. Crows of 120 bovine
incisors were prepared to obtain flat superficial dentin surfaces.
Dentin was etched with phosphoric acid and contaminated with fresh
blood for 10 seconds, before or after adhesive system application.
Different treatments were tested in contaminated dentin, resulting on
eight groups (N=15). Composite resin restorations (TPH Spectrum,
Dentsply) were adhesively fixed (Excite, Ivoclar-Vivadent) with resin
cement (Variolink 2, Ivoclar-Vivadent) and shear bond strength test
(0.5 mm/min) was performed. Morphologic observations were carried out
with scanning electron microscopy (SEM). Data (MPa) were submitted to
one-way ANOVA following Tukey’s test (p<0.05), showing that
blood contamination during adhesive procedure negatively affects bond
strength, and decontamination methods do not recover original bond
strength. The negative effects of blood contamination on shear bond
strength to dentin and resin cement were significant in all
contaminated groups; none of the tested dentin treatment procedures
resulted in higher bond strength irrespective of the moment on which
blood contamination took place
Influence of powder/liquid ratio on the radiodensity and diametral tensile strength of glass ionomer cements
Clinicians tend to make reductions in glass ionomer power/liquid (P/L) ratios since some materials are difficult to mix and flow into small cavities, grooves or pits. In general, changing the P/L ratio decreases the physical and mechanical properties of conventional glass ionomer cements (GICs) and resin modified glass ionomer cements (RMGICs), but alterations seem to depend on their composition. OBJECTIVE: To determine the influence of P/L ratio on the radiodensity and diametral tensile strength (DTS) of glass ionomer cements. MATERIAL AND METHODS: There were 2 factors under study: P/L ratio (manufacturer's recommended P/L ratio and a 50% reduced P/L ratio), and materials (Vitro Molar, Vitro Fil, Vitro Cem conventional GICs and Vitro Fil LC, Ortho Glass LC RMGICs. Five 1-mm-thick samples of each material-P/L ratio were produced for radiodensity evaluation. Samples were x-ray exposed onto Digora phosphor plate and radiodensity was obtained using the software Digora for Windows 2.5 Rev 0. For DTS, five (4.0x8.0 mm) cylinder samples of each material were tested (0.5 mm/min). Data were subjected to one- and two-way ANOVA (5x2) followed by Tukey's HSD test, or Kruskal-Wallis and Dunn's method. For paired comparisons, t-test or Mann-Whitney test were used (α=0.05). RESULTS: There was a significant interaction (P=0.001) for the studied factors (materials vs. P/L ratio). Reduced P/L ratio resulted in significantly lower DTS for the RMGICs, but radiodensity was affected for all materials (