RESUMO O objetivo desse estudo foi relatar o tratamento clínico de uma criança com Hipomineralização Molar Incisivo e, portanto, alto índice de sensibilidade dentária. Uma criança de cinco anos de idade, do gênero masculino, foi diagnosticada com Hipomineralização Molar Incisivo, relatando alta sensibilidade dentária. Após a anamnese e exame clínico, o tratamento iniciou-se com três aplicações de verniz fluoretado a 5% com complexo de CPP-ACP, associado à um dentifrício fluoretado contendo CPP-ACP (MI Paste Plus), em intervalos semanais. Após as três sessões de aplicação de verniz, os molares com grande perda de estrutura dentária foram restaurados com cimento de ionômero de vidro modificado por resina (Vitremer). Previamente à primeira aplicação tópica do verniz fluoretado com CPP-ACP e utilização do dentifrício fluoretado contendo CPP-ACP foi realizado um teste de sensibilidade dentária usando estímulo térmico e escala facial de dor, repetindo-se a cada sessão. Verificou-se que a sensibilidade diminuiu entre as sessões, com ausência de sensibilidade na última sessão antes da restauração. O tratamento de dentes com Hipomineralização Molar Incisivo utilizando-se o complexo CPP-ACP associado à aplicação tópica de flúor pode ser uma alternativa para redução da sensibilidade dentária.

ABSTRACT The objective of this study was to report the clinical treatment of a child with Incisor Molar Hipomineralization. A 5-year-old Brazilian child, male gender, was diagnosed with Molar Incisor Hypomineralization, reporting high teeth sensitivity. After anamnesis and clinical examination, treatment was conducted with three weekly applications of fluoride varnish containing 5% CPP-ACP complex. Also, it was advice to the patient for using a toothpaste containing fluoride and CPP-ACP (MI Paste Plus). After that, molars with great tooth structure loss were restored with resin modified glass ionomer cement. Prior to the first topical application of varnish with CPP-ACP and fluoride toothpaste containing CPP-ACP, a sensitivity test was conducted using thermal stimulus and facial pain scale. It was observed relative sensitivity decrease between sessions, reporting no sensitivity at the last session before the restoration. The treatment of Molar Incisor Hypomineralization teeth with CPP-ACP complex associated with fluoride varnish can be an alternative to reduce sensivity.

<sec><title>Aim:</title><p> The aim of this in vitro study was to investigate the synergistic effect of chemical degradation (erosion) and three-body abrasion (mechanical degradation) on the surface roughness (Ra) and hardness (KHN) of two nanorestorative materials and two conventional materials.</p></sec><sec><title>Methods:</title><p> Disc-shaped specimens (5 mm in diameter, 2 mm thick) of Filtek Z350^TM and TPH Spectrum^TM composites and Ketac Nano^TM and Vitremer^TM light-curing glass ionomer cements, nanomaterials and conventional materials were prepared according to the manufacturer's instructions. After 24 h, polishing procedures were performed and initial measurements of Ra and KHN were taken in all specimens. The specimens were divided into 12 groups (n = 10) according to material and storage media: artificial saliva, orange juice, and Coca-Cola(r). After 30 days of storage, the specimens were submitted to mechanical degradation and re-evaluated for Ra and KHN. Data were tested for significant differences by repeated-measure three-way ANOVA and Tukey's tests (p<0.05).</p></sec><sec><title>Results:</title><p> Erosion and abrasion wear significantly decreased hardness of all materials. Only Filtek Z350 roughness, however, was not affected by erosion and abrasion. All materials showed a significant increase in surface roughness after erosion and abrasion, except for Filtek Z350. After chemical and mechanical degradation, the KHN of all samples had decreased significantly. After mechanical degradation, the acidic drinks (Coca-Cola(r) and orange juice) were more aggressive than artificial saliva to all materials.</p></sec><sec><title>Conclusions:</title><p> A synergistic effect was observed by the increase in roughness for all materials, except for Filtek Z350; hardness values decrease for all materials, regardless of whether they were nanofilled or not. The RMGICs were more susceptible to degradation than the composites, considering both hardness and roughness surface parameters.</p></sec>

Este estudo avaliou o efeito da temperatura do ar e diferentes silanos na resistência de união entre pino de fibra e resina composta. Os pinos foram limpos com álcool e tratados com diferentes silanos: três pré-hidrolizados [Silano (Angelus), Prosil (FGM), RelyX Ceramic Primer (3M ESPE)] e um de dois componentes [Silane Coupling Agent (Dentsply)]. Duas temperaturas (23ºC e 60ºC) para secagem do silano foram aplicadas. Matriz plástica cilíndrica foi posicionada em torno do pino já silanizado, e preenchida com resina composta simulando núcleo de preenchimento. Cada cilindro obtido pela união pino/preenchimento foi seccionado, gerando 7 fatias para ensaio mecânico de push-out. Aplicou-se sobre cada fatia carregamento de compressão, com velocidade de 0,5 mm/min, até a falha da amostra. Os dados foram analisados pela ANOVA e teste Scott-Knott (α=0,05). Utilizou-se teste de Dunnett para comparação do grupo controle com cada um dos outros grupos experimentais. Após ensaio mecânico, observaram-se as amostras em microscópio eletrônico de varredura. Para 23ºC, RelyX Ceramic Primer apresentou os menores valores de resistência de união, enquanto o Silane Coupling Agent (Dentsply) obteve os maiores valores. Para o Silane Coupling Agent (Dentsply), os valores de resistência de união foram maiores para temperatura de 23ºC do que 60ºC. Em conclusão, o uso de ar quente após aplicação do silano não gerou aumento nos valores de resistência de união entre pino de fibra e material de preenchimento de resina composta. O silano de dois componentes apresentou maior resistência de união do que todos os silanos pré-hidrolizados quando usados na temperatura ambiente.

This study evaluated the effect of air drying temperature and different silane coupling agents on the bond strength between glass fiber posts and composite resin core. The post surface was cleaned with alcohol and treated with different silane coupling agents, being three prehydrolyzed silanes [Silano (Angelus), Prosil (FGM), RelyX Ceramic Primer (3M ESPE)] and one two-component silane [Silane Coupling Agent (Dentsply)]. Two post-silanization air drying temperatures, 23ºC and 60ºC, were applied. A cylindrical plastic matrix was placed around the silanized post and filled with composite resin. Each bonded post provided 7 slices for push-out testing. Each slice was loaded to failure under compression at a cross-head speed of 0.5 mm/min. Data were analyzed by two-way ANOVA and Scott-Knott tests (α=0.05). Dunnett's test was used to compare the mean of the control group with that of each experimental group. Scanning electron microscopy (SEM) was used to evaluate the interface of the fractured slices. For the 23ºC air drying temperature, the use of RelyX Ceramic Primer resulted in significantly lower bond strength than the other silane coupling agents, while the bond strength with Silane Coupling Agent was the highest of all groups. Only with Silane Coupling Agent, the bond strength for the 23ºC air drying temperature was significantly higher than that for 60ºC air drying. In conclusion, the use of warm air drying after silane application produced no increase in the bond strength between the fiber-reinforced composite post and the composite core. The two-component silane produced higher bond strength than all prehydrolyzed silanes when it was used with air drying at room temperature.

OBJECTIVE: The purpose of this study was to provide information regarding the marginal adaptation of composite resin onlays in primary teeth previously treated with 1% sodium hypochlorite (NaOCl) (pulp irrigant) using two different resin luting agents. MATERIAL AND METHODS: Forty extracted sound primary molars had their crowns prepared in a standardized machine and were randomly divided into 4 groups (n=10): G1 (1% NaOCl irrigation+EnForce); G2 (EnForce); G3 (1% NaOCl irrigation+Rely X); G4 (Rely X). The onlays were made with Z250 composite resin on plaster models. After luting, the tooth/restoration set was stored in 100% relative humidity at 37ºC for 24 h and finished with Soflex discs. Caries Detector solution was applied at the tooth/restoration interface for 5 s. The specimens were washed and four digital photos of each tooth were then taken. The extents of the gaps were measured with Image Tool 3.0 software. The percentage data were submitted to a Kruskal-Wallis test (α=0.05). The Relative Risk test analyzed the chance of a gap presence correlated to each group. RESULTS: There were no statistically significant differences (p>0.05) among the groups. The relative risk test revealed that some groups were more apt to have a presence of gaps than others. CONCLUSION: Neither the 1% NaOCl treatment nor the resin luting agents caused any alterations in the dental substrate that could have influenced the marginal adaptation of composite onlays in primary teeth.

O objetivo deste estudo foi verificar a freqüência da mastigação preferencialmente unilateral através da eletromiografia comparada à inspeção visual. Participaram deste estudo 29 indivíduos saudáveis, alunos do Curso de Odontologia - Uniararas, na faixa etária entre 18 e 25 anos, de ambos os gêneros, selecionados através dos critérios: dentição permanente completa ou apenas ausência dos 3os molares, sem sinais clínicos de disfunção craniomandibular ou doença periodontal. A análise eletromiográfica foi realizada nos músculos masseteres durante mastigação habitual de cenoura e parafilme. Considerou-se a presença de um lado de preferência mastigatória (LPM) quando os valores de amplitude de contração muscular obtidos em RMS (Root Mean Square) ou Valor Eficaz tivessem uma diferença de pelo menos 20% entre os músculos masseteres direito e esquerdo. A inspeção visual foi realizada por um único observador durante as aquisições eletromiográficas. Considerou-se a presença de um lado de preferência mastigatória quando a mastigação ocorria com uma freqüência de ciclos mastigatórios pelo menos 30% maior por um dos lados, após o registro de 20 ciclos mastigatórios consecutivos. Do total da amostra, 82,8% (24/29) e 72,4% (21/29) apresentaram um lado de preferência mastigatória durante a mastigação de cenoura e parafilme, respectivamente. A concordância entre a eletromiografia e a inspeção visual foi verificada em 83% das observações. Pode-se concluir que a maioria dos sujeitos examinados nessa pesquisa possuía um lado de preferência mastigatória durante mastigação habitual de cenoura e parafilme e que a eletromiografia pode ser usada como parâmetro para detecção do lado de preferência mastigatória.

The objective of this study was to verify the frequency of masticatory preferential side using electromyography exam compared to the visual inspection. The sample was comprised by 29 healthy students aged 18 to 25 years, of both sexes, from Araras School of Dentistry-UNIARARAS, Brazil, selected following approach: complete permanent dentition, except third molars, with no clinical signs of the temporomandibular dysfunction or periodontal disease. The electromyography analysis was accomplished in the right and left masseter muscles during habitual mastication of carrot and Parafilm. It was considered as presence on a masticatory preferential side and unilateral mastication when the muscular contraction width values obtained in RMS (Root Mean Square) has had at least 20% as a difference between the right and left masseter muscles. The visual inspection was carried out during the electromyography data acquisitions by only one observer. He determined the masticatory preferential side taking account the number of masticatory cycles developed by each side. The masticatory preferential side was considered when 30% of the cycles were developed in only one side after the registration of 20 consecutive masticatory cycles. Of the total sample, 82.8% (24/29) and 72.4% (21/29) exhibited a preferential masticatory side during habitual carrot and Parafilm mastication, respectively. The concordance level between the electromyography and visual inspection exams was 83% of the total observations. It could be concluded that most of the subjects examined in this study exhibited a masticatory preferential side and that the electromyography can be used as a parameter for the masticatory side detection.