Determinação do tempo de vida de restaurações totalmente cerâmicas (y-tzp/porcelana) com incidência da carga em diferentes regiões de contato

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise comparativa da ação antimicrobiana dos cimentos endodônticos Acroseal, Sealapex e AH plus pós presa em biofilme de enterococcus faecalis

Pós-graduação em Ciência Odontólogica - FOA

Influência de três tratamentos de superfície para cerâmicas a base de zircônia na resistência adesiva e no comportamento à fadiga do material

Pós-graduação em Odontologia Restauradora - ICT

Análise de blocos de concreto com resíduo de borracha de pneu e metacaulim

Pós-graduação em Engenharia Civil - FEIS

Concreto autoadensável utilizando cinza de casca de arroz: estudo das propriedades mecânicas

Pós-graduação em Engenharia Civil - FEIS

Avaliação da aplicação de ondas de ultra-som sobre cimentos de ionômero de vidro: rugosidade superficial e dureza

The application of ultrasonic waves during the initial setting of the glass ionomer cements (GIC) has demonstrated increase of the cure speed, reduction of air bubbles and improves in some mechanical properties. The aim of this study was to evaluate the effect of the ultrasound on the microhardness and the superficial roughness in two GICs (FUJI IX GP (GC Corporation) and Ketac Molar EasyMix (3M ESPE)). Forty specimens were confectioned, twenty for evaluation of the superficial roughness and twenty for evaluation of the microhardness. Half of them received for thirty seconds the ultrasonic waves application. The readings of the roughness had been carried before and after the toothbrushing test. The twenty remaining specimens had been polished with abrasive sandpapers of decreasing granulations and submitted to the hardness test. The results, analyzed for the variance analysis (ANOVA) (p<0,05), had demonstrated increase of the hardness for all the groups with the application of ultrasonic waves, being bigger for the Ketac Molar EasyMix. The ultrasound application also caused significant reduction of the superficial roughness for the Ketac Molar EasyMix. After the toothbrushing test, this last property increased for all the materials. It could be concluded that the application of ultrasonic waves was effective in increasing the superficial hardness of the materials and that it improved the roughness of the Ketac Molar EasyMix before the toothbrushing test.

Effect of ultrasonic ecxitation on the ultimate tensili strength of glass ionomer cements after different water storage times

The application of ultrasound waves with a conventional dental ultrasonic scaler on glass ionomer cements surface accelerated initial setting reaction and improved the mechanical properties. Objective: This study evaluated the ultimate tensile strength of glass ionomer cements after ultrasonic excitation and different water storage times. Material and method: Twelve specimens of each material (Fuji IX GP, Ketac Molar Easymix and Vitremer) were prepared, and six of each received a 30-second ultrasound application during initial setting of the cements. After storage of the 24 hours or 30 days, the specimens were sectioned into stick to microtensile testing and the mean ultimate tensile strength values were submitted to Welch’s ANOVA and Tamhane’s test. Result: The results showed that the Vitremer presented the highest mean tensile strength. The chemically set Fuji IX GP presented significantly higher mean tensile strength after 30 days than after 24 hours of storage (p < 0.05). At 24 hours, the ultrasonically set Fuji IX GP presented significantly higher mean tensile strength than their counterparts set under standard conditions (p < 0.05). Conclusion: Treatment with ultrasound increased the tensile strength of Fuji IX GP in the early period of maturation.

Dureza e rugosidade superficial de cimentos de ionômero de vidro após ensaio de escovação

To evaluate the surface roughness and Vickers hardness of glass ionomer cements Ketac Molar® and Ketac Molar Easy Mix® (ESPE Dental AG) after brushing. Methods – After roughness and hardness tests of 14 specimens of each material, they were submitted to 30,000 brushing cycles and new analysis of roughness and hardness. Statistical analysis showed that there was no significant difference between the materials in relation to the initial roughness. Results – However, after brushing there was higher surface roughness for Ketac Molar Easy Mix®. For both materials, there was increase of hardness after brushing and the highest values were presented by Ketac Molar Easy Mix®. Conclusion – It can be concluded that, when choosing a glass ionomer cement for restoration it should be preferred to Ketac Molar, because it showed hardness similar to Ketac Molar Easy Mix, but it was less rough.

Reparo periapical de dentes tratados endodonticamente submetidos a movimentação ortodôntica

The relationship of Orthodontics and Endodontics is being clarified with the development of evidence-based dentistry. However, few studies have reported the repair of periapical lesions with orthodontic treatment. Therefore, the aim of this study was to evaluate the available evidence on periapical repair of endodontically treated teeth during orthodontic movement. The strategy used was the electronic search with keywords and criteria including studies published up to July 2011. It was also carried out qualitative assessment of the articles methodology. Although a significant number of studies have reported this topic, only two filled the criteria for inclusion in this systematic review. The results obtained in the literature suggest that orthodontic treatment should be interrupted to perform endodontic treatment. During this therapy, the use of root canal dressing based on calcium hydroxide for at least 14 days, and sealer with adequate biological property are indicated. After this phase, orthodontic movement of the endodontically treated teeth can be resumed without waiting period.

Fotocatálise heterogênea de enterococcus faecalis e pseudomonas aeruginosa desencadeada pela ação da luz UV e branca em espátulas com revestimento de nanopartículas TiO2 e Ag

Nanotechnology, the science of minuscule, has developed products which are able t o manipulate atoms and molecules that could be applied in the sterilization process of dental instruments. Objetives: The objective of the present study was to evaluate the self-cleaning action of TiO2 and Ag nanoparticles coating on dental instruments by the photocataliys process under UV and visible light irradiation. Material and method: Microbiologic tests were done using dental cement spatulas coated with TiO2 and Ag nanoparticles (one or three layers), and contaminated with 10 mcrl of Pseudomonas aeruginosa and Enterococcus faecalis, respectively. After contamination, they were exposed to ultraviolet light and visible light for 120 minutes. Next, they were transferred to and stored in test tubes with BHI (Brain Heart Infusion) and incubated in 35 to 37 °C. Checking times for bacterial growth and for control and retrieval tests were done at: 24, 48, 72 and 96 hours. Result: The Pseudomonas aeruginosa was inactive after 120 minutes of ultraviolet light irradiation, thus confirming the heterogeneous photocatalytic activity of TiO2 and Ag. The Pseudomonas aeruginosa was not inactivated under visible light irradiation and the Enterococcus faecalis was not inactivated under UV and visible light irradiation of the dental cement spatulas coated with TiO2 and Ag nanoparticles in the readings to 96 hours, showing bacterial growth. Conclusion: There were no influence of one or three layers of TiO2 and Ag nanoparticles coating of the spatulas in the results. The heterogeneous photocatalysis activity of TiO2 and Ag under UV light irradiation was confirmed for Pseudomonas aeruginosa but not under visible light. Enterococcus faecalis did not confirmed the photocatalytics activity of TiO2 and Ag under UV light irradiation and visible lights irradiation.

Considerações gerais sobre prótese fixa adesiva

The success rate of resin-bonded fixed partial dentures is directly related to the adhesive system and the tooth preparation design for good retention. These resin-bonded bridges represent a prosthodontic alternative, based on their costeffectiveness, conservative techniques, and ease of laboratory manufacturing. Through a thorough review of the literature, this study aimed to report on cavity designs, types of materials used, and the advantages and disadvantages of the resin-bonded fixed partial denture. One of significant advantages of the resin-bonded fixed partial dentures is the conservation of the tooth structure, whereas its main disadvantage includes aesthetic limitations, given that the alloy may in fact be visible. Preparation design, cement type, and casting alloy type, as well as surface treatment, are among the factors that influence the longevity of resin-bonded fixed partial dentures. Treatments with resin-bonded fixed partial dentures present a bright outlook regarding the conservation of tooth structures, as well as a high level of success.

Hipersensibilidade dentinária cervical: em busca de um tratamento eficaz

The knowledge of the etiology of any disease or condition is paramount to a safe and effective treatment. This literature review aims to show some options to treat dentine hypersensitivity (HSDC). The loss of cervical enamel and cementum exposure of tubules leads to a painful condition and patient discomfort, called HSDC. This loss of tooth structure occurs due to formation of cervical lesions in cases of gingival recession, abrasion, erosion, or abfraction by the association of two or more factors. Some treatments are not effective, but there are effective therapies, such as: application of ferric oxalate, potassium oxalate, potassium nitrate, fluoride varnish, solutions of calcium phosphate, adhesives and Bonding procedures. Therefore, the identification and removal of etiological factors is essential to successful treatment of HSDC normally associated to tubules obliterate and consequent reduction of fluid motion within the dentin.

Influência da reinstrumentação do degrau apical radicular após o posicionamento primário do cone principal de guta-percha noselamento apical

The aim of this study was to evaluate in vitro the apical leakage after the apical re-preparation and replacement of the principal gutta-percha point plus endodontic sealer (Sealer 26TM). Sixty extracted human canines were prepared by using a step back technique up to size 50 K type file apically. At each change of instrument the canals were irrigated with distilled water. After that step, the external surface roots were coated and subdivided into six groups with ten roots each: I – single gutta percha point technique; II – lateral condensation and III – hybrid technique. The IV, V and VI groups were similar to others groups but after to place the principal gutta percha point, it was removed, re-prepared up to size 60K file and in sequence replaced the principal gutta percha point and the root canal filling finished. The specimens were immersed in 2% Rhodamine BTM for 7 days at 37 oC. The apical leakage was measured by Image ToolsTM program. With Kruskal Wallis test statistical analysis showed that there was no significant difference between the techniques (p > 0.05).

Avaliação do pH, da solubilidade e da infiltração marginal em retrobturações com o Sealer 26 puro ou acrescido de iodofórmio

Sealer 26® cement contains bisphenol epoxy resin associated with calcium hydroxide, presenting smaller radiopacity than other endodontic cements. Aiming to improve this property, iodoform has been added in its composition. However, this addition's possible changes in physical and chemical properties still need to be studied. OBJECTIVE: To evaluate the apical sealing ability, solubility, and pH of Sealer 26® alone or with iodoform, at several proportions. MATERIAL AND METHODS: Three experimental mixtures of Sealer 26®, alone or with iodoform, were prepared and subjected to solubility test. Additionally, these combinations were inserted into polyethylene tubes and immersed in distilled water, and, their pH was evaluated after 24-h and 7-day periods. Subsequently, forty roots of extracted lower incisors subdivided into four groups of 10 specimens each, were retrograde filled with one of the previously described mixtures and gutta-percha points. The roots were immersed in Rhodamine B, under vacuum, for 72 hours. After this period, the specimens were longitudinally sectioned, root fragments photographed, these images scanned, and apical infiltration measured by Image tool software. The obtained data were subjected to statistical analysis, at a significance level of 5%. RESULTS: Marginal leakage and solubility tests did not show any difference among the experimental groups (p > 0.05). pH analysis was only statistically different at 24-h period and between Sealer 26® alone and 1.1g iodoform group (p < 0.05). CONCLUSION: The presence of iodoform in Sealer 26®, at the used proportions, did not alter the solubility, apical marginal leakage and pH properties of the original cement.

Reabilitação estético-funcional sobre implantes agulhados e endósseos

This report shows the resolution of a case study whose aim was promote the aesthetic and functional rehabilitation of upper left hemi-arch over endosseous and needle implant prostheses. To improve the position of the needle implants, we performed the bucco-palatal bending of needles splinting them with composite resin; we removed the screwed implant prosthesis in the regions of the premolars (24 and 25) and molar (26). The mini-abutments of the last two implants were replaced, and in the first premolar and canine, we used cemented abutments due to implant angulation having planned soldering because of implant size and contact with one needle implant that could interfere with intimate contact bone/implant damaging biomechanics. Pick-up impressions were performed with an open tray, using a retractor cord in the needle implants and respective transfer copings. Therefore, models were related on semi-adjustable articulator after a face-bow recording and interocclusal indexes. After working cast fabrication and try-in of infra-structures, these were adjusted and related into the articulator again. Then, after ceramic build-up, adjustments, finishing, and torque, chemically-activated resin cement was applied on units 21 to 24. At the end of the case, we concluded that a good aesthetic and functional rehabilitation depends on thorough knowledge of techniques for each clinical situation.