Efeito da contaminação salivar e do tempo de recondicionamento ácido na resistência da união ao cisalhamento de um selante de fóssulas e fissuras

O propósito deste estudo foi avaliar o efeito do tempo de contaminação salivar (TCS) e de recondicionamento ácido (TRA) na resistência da união ao cisalhamento (RC) do selante Fluroshield. Foram selecionados 45 terceiros molares. Os dentes foram seccionados no sentido mésio-distal e suas superfícies foram lixadas até a obtenção de uma área plana em esmalte. Em seguida, as amostras foram distribuídas aleatoriamente em 9 grupos (n=10), em função do TCS e TRA (segundos), respectivamente: G1 - controle; G2 - 30 e 0; G3 - 60 e 0; G4 - 30 e 2; G5 - 30 e 5; G6 - 30 e 15; G7 - 60 e 2; G8 - 60 e 5; G9 - 60 e 15. Em seguida, foi realizada a aplicação do selante de acordo com as instruções do fabricante. Os corpos-de-prova obtidos foram armazenados em água destilada a 37ºC por 72 horas, e então submetidos ao ensaio de cisalhamento à velocidade de 0,5mm/min. Os resultados foram submetidos à análise de variância (ANOVA), e indicaram que não houve diferença estatística significativa (p>;0,05) entre todos os grupos. Observou-se que: 1 - quanto maior o TCS, menores os valores de RC (MPa); 2- quanto maior o TRA, maior o valor de RC (MPa). Pôde-se concluir que houve uma tendência para o menor TCS (30s) e os maiores TRA (5 e 15s) em retornar aos valores de RC do grupo controle.The aim of this study was to evaluate the effect of saliva contamination (SCT) and re-etching time (RET) on the shear bond strength (SBS) of the Fluroshield sealant. Forty-five extracted third molars were sectioned and flattened until reach an enamel surface area. Then, all samples were etched for 30 sec with 35% phosphoric acid and then they were distributed into 9 groups (n=10) according to SCT and RET (seconds), respectively: G1- control (no SCT and no RET); G2- 30s and 0s; G3- 60s and 0s; G4-30s and 2s; G5- 30s and 5s; G6- 30s and 15s; G7-60s and 2s; G8- 60s and 5s; G9- 60s and 15s. The sealant was applied according to the manufacturer's instructions. The samples were stored in distilled water at 37ºC for 72h and subjected to the SBS test. The results indicated that there was no statistically significant difference between the groups (p>;0.05). However, it could be noticed that: 1- the longer the SCT, the lower the SBS values; 2 - the longer the RET, the higher the SBS values. It could be concluded that there was a tendency to the shortest SCT (30s) associated to the longest RET (5 and 15s) to reach similar SBS values for the control group

Morphological And Chemical Changes In Dentin After Using Endodontic Agents: Fourier Transform Raman Spectroscopy, Energy-dispersive X-ray Fluorescence Spectrometry, And Scanning Electron Microscopy Study.

We examine the morphological and chemical changes in the pulp chamber dentin after using endodontic agents by scanning electron microscopy (SEM), Fourier transform Raman spectroscopy (FT-Raman), and micro energy-dispersive x-ray fluorescence spectrometry (μEDXRF). Thirty teeth were sectioned exposing the pulp chamber and divided by six groups (n=5): NT-no treatment; CHX-2% chlorhexidine; CHXE-2% chlorhexidine+17% EDTA; E-17% EDTA; SH5-5.25% NaOCl; SH5E-5.25% NaOCl+17% EDTA. The inorganic and organic content was analyzed by FT-Raman. μEDXRF examined calcium (Ca) and phosphorus (P) content as well as Ca/P ratio. Impressions of specimens were evaluated by SEM. Data were submitted to Kruskal-Wallis and Dunn tests (pNT=SH5E>CHX>E>CHXE). CHXE and E presented the highest Ca/P ratio values compared to the other groups (p<0.05). The SEM images in the EDTA-treated groups had the highest number of open tubules. Erosion in the tubules was observed in CHX and SH5E groups. Endodontic agents change the inorganic and organic content of pulp chamber dentin. NaOCl used alone, or in association with EDTA, was the most effective agent considering chemical and morphological approaches.1707500

Aesthetic and functional rehabilitation of anterior teeth after trauma: a case report

Traumatic dental injuries are common clinical problems during childhood, and may have complex etiologies causing physical and physiological impairment. The aim of this study was to report the management of a severe traumatic dental injury in an 8-year-old female patient, victim of a motorcycle accident, who was taken to a pediatric dentistry clinic three months after the accident. After clinical and radiografic examination, we observed the avulsion of the permanent maxillary central incisors and of the permanent left lateral incisor, with considerable lingual interposition, interfering in speech and swallowing. The patient showed low risk of caries and good behavior during the appointments. However, she demonstrated to be embarrassed to smile. Besides the preventive treatment concerning caries, the treatment plan included immediate care and subsequent monitoring of the psychosocial reestablishment. For this purpose, an acrylic partial denture was made in order to replace the missing anterior teeth, maintaining the characteristics of the mixed dentition and preserving the aesthetics and the function. Follow-up appointments were performed one, three and six months after the first visit, aiming to monitor the adaptation of the prosthesis, as well as the growth and development of the child’s dentition. Thus, the aesthetic and functional rehabilitation was achieved regarding the patient’s satisfaction, enabling immediate social reinsertion.Lesões dentárias traumáticas são problemas clínicos comuns durante a infância e podem ter etiologias complexas, causando deficiências físicas e fisiológicas. O objetivo deste estudo foi relatar um caso de lesão dentária traumática grave em uma paciente de 8 anos de idade, vítima de um acidente de moto, que foi levada para uma clínica de odontopediatria três meses depois do acidente. Exames clínicos e radiológicos diagnosticaram a avulsão dos incisivos centrais superiores permanentes, do incisivo lateral esquerdo permanente e do canino esquerdo decíduo, com considerável interposição da língua, interferindo na fala e deglutição. A paciente apresentou baixo risco de cárie e bom comportamento durante as consultas. No entanto, ela demonstrou estar envergonhada para sorrir. Além do tratamento preventivo para a cárie, o plano de tratamento incluiu atendimento imediato e acompanhamento posterior do restabelecimento psicossocial da paciente. Para este efeito, uma prótese parcial acrílica foi feita para substituir os dentes anteriores que faltavam, mantendo as características da dentição mista e preservando sua estética e função. Consultas de acompanhamento foram realizadas em um, três e seis meses após a primeira visita, com o objetivo de monitorar a adaptação da prótese, bem como o crescimento e desenvolvimento da dentição da criança. Assim, a reabilitação estética e funcional foi alcançada considerando a satisfação da paciente, permitindo sua reinserção social imediata

Effect of the Polishing Procedures on Color Stability and Surface Roughness of Composite Resins

Objectives. To evaluate the polishing procedures effect on color stability and surface roughness of composite resins. Methods. Specimens were distributed into 6 groups: G1: Filtek Supreme XT + PoGo; G2: Filtek Supreme XT + Sof-Lex; G3: Filtek Supreme XT + no polishing; G4: Amelogen + PoGo; G5: Amelogen + Sof-Lex.; G6: Amelogen + no polishing. Initial color values were evaluated using the CIELab scale. After polishing, surface roughness was evaluated and the specimens were stored in coffee solution at 37°C for 7 days. The final color measurement and roughness were determined. Results. Sof-Lex resulted in lower staining. Amelogen showed the highest roughness values than Filtek Supreme on baseline and final evaluations regardless of the polishing technique. Filtek Supreme polished with PoGo showed the lowest roughness values. All groups presented discoloration after storage in coffee solution, regardless of the polishing technique. Conclusion. Multiple-step polishing technique provided lower degree of discoloration for both composite resins. The final surface texture is material and technique dependent

Chx stabilizes the resin/demineralized dentin interface

The aim of this study was to evaluate the effect of 2% chlorhexidine diglueonate (CHX) on microtensile bond strength (μTBS) between an adhesive system and under 3 dentin conditions. For that, this study evaluated the adhesive interface at initial, after 6 months and 1 year of storage. Forty-eight human third molars were prepared and randomly divided into 3 groups, according to dentin substrates: Sound dentin (Sd), caries-infected dentin (Ci) and caries-affected dentin (Ca). The groups were subdivided into two according to the dentin pre-treatment: Application of 2% CHX or without pre-treatment (control). The dentin surfaces were etched with 35% phosphoric acid gel and bonded with Adper Single Bond 2 (3M ESPE) adhesive system according to manufacturer's instructions. Subsequently, the specimens were stored in deionized water at 37°C for 24h, 6 months and 1 year. Two additional teeth were used to analyze the bonding interfaces by SEM. Data was submitted to three-way ANOVA in a split plot design and Tukey's test (α = 0.05). The results showed that Ci decreased μTBS values when compared to Ca and Sd, regardless storages time or treatment. Stored samples for 6 months and 1 year decreased the pTBS for the control group, but no difference was found between storages time for the CHX group. As a conclusion, the 2% CHX application after etching showed improved dentin bond strength in the storage time, regardless of the substrates evaluated

Analysis by confocal laser scanning microscopy of the MDPB bactericidal effect on S. mutans biofilm CLSM analysis of MDPB bactericidal effect on biofilm

Since bacteria remain in the dentin following caries removal, restorative materials with antibacterial properties are desirable to help maintaining the residual microorganisms inactive. The adhesive system Clearfil Protect Bond (PB) contains the antibacterial monomer 12-methacryloyloxydodecylpyridinium bromide (MDPB) in its primer, which has shown antimicrobial activity. However, its bactericidal effect against biofilm on the dentin has been little investigated. Objective: The aim of this study was to analyze by confocal laser scanning microscopy (CLSM) and viable bacteria counting (CFU) the MDPB bactericidal effect against S. mutans biofilm on the dentin surface. Material and methods: Bovine dentin surfaces were obtained and subjected to S. mutans biofilm formation in BHI broth supplemented with 1% (w/v) sucrose for 18 h. Samples were divided into three groups, according to the primer application (n=3): Clearfil Protect Bond (PB), Clearfil SE Bond, which does not contain MDPB, (SE) and saline (control group). After the biofilm formation, Live/ Dead stain was applied directly to the surface of each sample. Next, 10 µL of each primer were applied on the samples during 590 s for the real-time CLSM analysis. The experiment was conducted in triplicate. The primers and saline were also applied on the other dentin samples during 20, 90, 300 and 590 s (n=9 for each group and period evaluated) and the CFU were assessed by colonies counting. Results: The results of the CLSM showed that with the Se application, although non-viable bacteria were detected at 20 s, there was no increase in their count during 590 s. In contrast, after the PB application there was a gradual increase of non-viable bacteria over 590 s. Conclusions: The quantitative analysis demonstrated a significant decrease of S. mutans CFU at 90 s PB exposure and only after 300 s of Se application. Protect Bond showed an earlier antibacterial effect than Se Bond