Is immediate dentin sealing a mandatory or optional clinical step for indirect restorations?

OBJECTIVE: The use of immediate dentin sealing (IDS) following tooth preparation for indirect restorations is well-supported by laboratory studies. The inclusion of IDS as a mandatory clinical step, it must be firmly supported by evidence from randomized clinical trials (RCT). The objective of this study is to assess whether IDS should be added as a mandatory procedure in all indirect restorations, taking into consideration clinically significant outcomes for the patient, such as restoration longevity and hypersensitivity. MATERIALS AND METHODS: A bibliographic search was carried out in the PubMed. In addition, a manual search was conducted in the references of literature reviews. RESULTS: Data from four RCT were included. Two studies assessed preparations for full crowns, and two assessed preparations for partial restorations. Data from full crown preparations were subjected to a meta-analysis, revealing a reduction in hypersensitivity incidence in the IDS group 1 week after restoration cementation. With respect to hypersensitivity, IDS seems to offer advantages exclusively during the provisional phase and up to 1 week following the cementation of the final restoration. One study has shown no difference on longevity. CONCLUSION: The use of IDS should be considered as an elective clinical step during the rehabilitation with indirect restorations. CLINICAL SIGNIFICANCE: IDS is an elective clinical step that should be considered in patients and preparations with a higher risk of sensitivity between appointments.

Color variation of composite resins in relation to the Vita Classical shade guide: colorimetric analysis

Aim: The aim of this study was to verify the color variation between different composite resins and the Vita Classical Shade Guide. Methods: Two-millimeter thickness samples were made (n = 6) from eight commercial brands of composite resin (shade A2): Charisma (Kulzer), Forma (Ultradent), Harmonize (Kerr), Luna (SDI), Opallis (FGM), Oppus Bulk Fill (FGM), Vittra (FGM) and Filtek Z250 XT (3M ESPE). Specimens were stored in distilled water for 7 days and then polished. Color measurements of samples and A2 shade of the Vita Classical Shade Guide were performed using the Vita Easy Shade Advance 4.0 spectrophotometer on a black background. Color variations were calculated using the CIEDE2000 formula, considering values ≥0.81 being noticeable by the human eye and ≥1.77 being clinically unacceptable. Results were statistically analyzed with a 5% significance level. Results: Color variation (ΔE) of composite (E1 ) compared to the Vita Classical Shade Guide (E0 ) was greater than clinically acceptable for all the materials evaluated in this study. Forma (ΔE=2.08 ± sd=0.47) and Filtek Z250 XT (2.50 ± 0.20) had the smallest amount of color variation values found in the results. Harmonize (3.32 ± 0.63) presented values similar to Filtek Z250 XT, but it was worse than Forma. Vittra (3.51 ± 0.28), Charisma (3.80 ± 0.20), Opallis (4.24 ± 0.30) and Luna (5.67 ± 0.20) did not differ among each other and presented higher color variation than Forma, Filtek Z350XT and Harmonize. Oppus Bulk Fill (13.94 ± 1.12) was the composite with the greatest color variation. Conclusions: The findings in this study show that attention should be taken when using the Vita Color Shade Guide for composite shade selection

Influence of the incorporation of titanium dioxide nanofibers net on bond strength and morphology of a total etching adhesive system.

Background: The aim of this study was to evaluate the nanoleakage and microtensile bond strength (µTBS) of an ethanol based-adhesive containing Titanium dioxide (TiO2) nanofibers to dentin. Material and Methods: TiO2 nanofiber was produced by electrospinning and it was inserted in an ethanol-based adhesive in 0.5, 1.5 and 2.5% by weight. The original adhesive did not receive nanofiber. The middle dentin was exposed by diamond saw under water-cooling and dentin was polished with wet 600-grit SiC abrasive paper. Resin composite build-ups were applied incrementally to the dentin after adhesive application. After storage in distilled water (24 hours/37°C) the teeth were sectioned perpendicularly to the bonded interface and sticks were obtained. Twenty-five sticks per group were tested by µTBS with a crosshead speed of 0.5mm/minute. The average values (MPa) obtained in each substrate were subjected to one-way ANOVA (α=0,05) with the tooth being considered the experimental unit. The nanoleakage pattern was observed in ten sticks per group and analyzed by Chi-square test (α=0,05). Results: There was no difference in µTBS among the experimental groups. However, there was a statistically significant difference among 2.5 % nanofiber adhesive, 0.5 % nanofibers and control groups, (p=0,028) in relation to nanoleakage. Conclusions: TiO2 nanofibers in 2.5% of weight inserted in dental adhesive reduced the nanoleakage, but did not improve the µTBS to dentin. Key words:Dentin-bonding agents, nanoleakage, tensile bond strength.

Cytotoxicity assessment of Bio-C Repair Íon+: A new calcium silicate-based cement.

Background. Direct pulp capping is a method designed to preserve the exposed dental pulp. Due to good biological, physical, and mechanical properties, new versions of calcium silicate-based materials have been developed as pulp capping materials. The present study aimed to evaluate the cytotoxic effects of four calcium silicate-based pulp capping materials, of which the Bio-C Repair Íon+ is still in an experimental phase. Methods. Biodentine, MTA Repair HP, Bio-C Repair, and Bio-C Repair Íon+ cements were dispensed in a metallic matrix to produce 125-mm3 specimens, which were immersed in Dulbecco's Modified Eagle Medium (DMEM) to obtain extracts. NIH 3T3 cells were cultured and exposed to the extracts for 24 hours and seven days. Cell viability was assessed by the methyl tetrazolium test (MTT). The mean values for the experimental and control groups (without treatment) were compared by analysis of variance (ANOVA) and post hoc Tukey tests, considering a significance level of 5%. Results. All the tested materials demonstrated a reduction in cell viability (P < 0.05). According to ISO 10993-5: 2009 (E), Bio-C Repair Íon+ exhibited mild and moderate cytotoxicity in the 24- hour and 7-day analyses, respectively. Bio-C Repair and Biodentine showed mild cytotoxicity, and MTA Repair HP exhibited moderate cytotoxicity at both intervals. Conclusion. The highest cell viability was demonstrated by Biodentine, MTA, and Repair HP, in descending order. Bio-C Repair and Bio-C Repair Íon+ showed moderate cytotoxicity, similar to MTA Repair HP in the 7-day analysis.

Effect of heat treatment on cytotoxicity and polymerization of universal adhesives.

To assess, in vitro, the influence of heat air treatment on cytotoxicity and degree of conversion (DC) of universal self-etch adhesives (Ambar Universal APS, Scotchbond Universal Adhesive, and Tetric N-Bond Universal) in an NIH/3T3 fibroblast cell culture. Samples were divided into three groups: 1) no heat treatment (control), 2) 37°C and 3) 60°C heat treatment before photopolymerization. Cytotoxicity was analyzed by MTT assay and the DC by FTIR. All adhesives heated at 60°C showed reduced cytotoxicity levels when compared with those heated at 37°C. In general, DC of Ambar Universal APS presented the highest DC than Scotchbond Universal Adhesive and Tetric N-Bond Universal, and the hot air treatment do not influence the conversion. Heat treatment at 60°C was able to reduce the cytotoxicity of universal self-etch adhesives, even, the heat treatment does not enhances the DC.

Hot air stream reduces cytotoxicity of light-cured calcium hydroxide based cements.

BACKGROUND: The light-cured calcium hydroxide based cements have incomplete polymerization and unconverted monomers can cause pulp cell damage. The aim of this study was to evaluate the influence of a warm and hot air stream on the cytotoxicity of light-cured calcium hydroxide based cements. MATERIAL AND METHODS: The materials Dycal (conventional cement), Biocal, Hidrox-Cal, and Ultra-Blend Plus (light-cured calcium hydroxide cements) were submitted to cytotoxicity analysis after polymerization, without vs. with previous heat treatment with a warm (37°C) and a hot (60°C) air stream. Following polymerization, cements were maintained in culture medium for 24 hours and 7 days, and subjected to the MTT test. Data were analyzed using analysis of variance (ANOVA) followed by post-hoc Student-Newman-Keuls (<0.05). RESULTS: The results indicated significant differences between the materials according to their composition, i.e., light-cured cements treated with a jet of warm air showed similar cytotoxicity levels to those observed for conventional cement, suggesting that they may be considered alternatives in cases requiring pulp-capping treatment. CONCLUSIONS: Application of a hot air stream reduced cytotoxicity of materials tested. Key words:Dental pulp capping, dental cements, calcium hydroxide, cell survival.

Evaluation of Tensile Bond Strength of Metallic Prefabricated Posts Cemented with Different Luting Agents

Abstract Objective: To assess the tensile bond strength of prefabricated metal posts cemented with different luting agents. Material and Methods: Fifty single-rooted endodontically treated human teeth had their crowns cut, mounted into acrylic-resin blocks and then an 8mm depth post space were prepared. Prefabricated cylindrical metal posts were cemented using different luting agents: a zinc phosphate cement (SS White), a conventional glass ionomer cement (Vidrion C), two resin-modified glass ionomer cements (Vitremer and RelyX Luting 2) and a resin cement (RelyX ARC). Samples were stored in distilled water for seven days and then submitted to a tensile bond strength test until complete dislocation of the post. One-way analysis of variance and Tukey test for pairwise multiple comparisons were used to evaluate differences between luting agents. Results: Tensile bond strength was 563.88±203.41 N for zinc phosphate cement, 336.86 ± 137.64 N for Vidrion C, 515.24 ± 239.48 N for Vitremer, 828.47±433.99 N for RelyX Luting 2 and 1262.51 ± 356.29 for RelyX ARC. The Relyx ARC presented the highest tensile bond strength regard the luting agent tested (p< 0.05). Conclusion: RelyX ARC presented the higher tensile bond strength compared to the other luting agents evaluated.

Restauração de dentes tratados endodonticamente com resinas bulk-fill: revisão integrativa / Endodontically treated teeth restored with bulk-fill resins: integrative review

Objetivo: realizar uma revisão de literatura sobre o uso de resinas bulk-fill para restaurar dentes tratados endodonticamente. Materiais e método: a busca dos estudos, clínicos ou laboratoriais, foi realizada no portal PubMed, utilizando os descritores "bulk fill" e "endodontically treated". Os dados extraídos da literatura foram agrupados em um quadro, que apresenta as características metodológicas e os principais resultados de cada estudo. Resultados: Sete estudos foram incluídos na revisão. Dentre eles, cinco avaliaram a resistência à fratura dos dentes após a restauração, um avaliou a adaptação da resina ao assoalho da câmara pulpar, e um realizou um ensaio clínico com acompanhamento de três anos, comparando o uso de resina bulk-fill com resina convencional. Considerações finais: o desempenho das resinas bulk-fill mostrou-se semelhante ao das resinas convencionais nas características de resistência à fratura dos dentes (in vitro) e longevidade (in vivo). A economia de tempo clínico proporcionada pelas resinas bulk-fill pode justificar o seu emprego para a restauração de dentes tratados endodonticamente. (AU)

Objective: the aim of this study was to review the literature regarding the use of bulk-fill resin to restore endodontically treated teeth. Materials and method: the search was performed at PubMed, using the descriptors "bulk fill" AND "endodontically treated". Clinical and laboratorial studies were included. The extracted data was presented on a table showing the methodological features and results of each study. Results: seven studies evaluated the bulk-fill resin on direct restoration. Five of these seven evaluated the resistance to fracture, one assessed the resin adaptation to the floor chamber, and one was a randomized clinical trial comparing the bulkfill resin to conventional resin. Final considerations: the performance of bulk-fill resins was similar to the conventional resins when compared to the in vitro studies on tooth fracture resistance and in vivo study on longevity of restorations. The economy of clinical time may justify its use to restore endodontically treated teeth. (AU)

O papel das mídias sociais na construção do conhecimento em Odontologia / The role of social media in the construction of knowledge in Dentistry

Este artigo, de cunho teórico, discute a construção do conhecimento em Odontologia no contexto da Sociedade em Rede, aproximando essa temática ao ponto de vista de alguns autores das Ciências Sociais Contemporâneas em voga. A bibliografia especializada aponta que a sociedade vive em uma constante transformação. Prova disso é que a construção de conhecimento pedagógico em Odontologia se dá hoje com maior intensidade na internet, principalmente nas mídias sociais, do que através da busca em livros. Por essa nova forma de agregar conhecimento ser uma realidade, é de fundamental importância que pessoas qualificadas sejam vetores de transmissão desses conhecimentos, de uma forma didática e com embasamento científico. Além disso, cabe aos professores se adaptarem ao novo estilo de construção do conhecimento pedagógico, elaborando aulas mais interativas e com o auxílio de ferramentas que chamem a atenção dos seus alunos e, concomitante a isso, ofereçam-lhes informações de qualidade.

This theoretical article discusses the construction of knowledge in dentistry in the context of the Network Society, bringing this theme closer to the point of view of some contemporary Social Science writers, nowadays in vogue. The specialized bibliography indicates that the society lives in a constant transformation, proof of this is that the construction of pedagogical knowledge in dentistry occurs today with greater intensity in the internet, mainly in the social media, than through the search in books. Because this new form of knowledge aggregation is a reality, it is of fundamental importance that qualified people are vectors of transmission of this knowledge, in a didactic and scientific basis. In addition, it is up to teachers to adapt to the new style of construction of pedagogical knowledge, developing more interactive classes and with the help of tools that attract the attention of their students and, at the same time, offer them quality information.

Effect of heat treatment on cytotoxicity of self-adhesive resin cements: Cell viability analysis.

OBJECTIVE: The aim of the study was to assess, in vitro, the influence on cytotoxicity of heat treatment applied before photopolymerization, while mixing three self-adhesive resin cements, in an NIH/3T3 fibroblast cell culture, based on cell viability measures. METHODS: Samples were divided into three groups: (1) no heat treatment while mixing (control), (2) 37°C, and (3) 60°C heat treatment while mixing. Cements were light-cured immediately after mixing and immersed in Dulbecco's Modified Eagle Media for the extraction of possibly uncured products after 24 h and 7 days. Cultures contained 0.5 mL of NIH/3T3 fibroblasts per well at a concentration of 0.4 × 105 cells/mL and specific extracts for each sample. STATISTICAL ANALYSIS USED: Data were statistically analyzed with ANOVA and post hoc Student-Newman-Keuls (significance of 5%). RESULTS: Cement cytotoxicity increased with time, as shown by the higher values observed at 7 days. There was a slight difference in intragroup cytotoxicity levels between 24 h and 7 days. Heat treatment at 60°C was associated with a major decrease in cytotoxicity levels in all three groups, both at 24 h and at 7 days, with no differences among the cements. CONCLUSIONS: Heat treatment at 60°C should be considered as a strategy to reduce cytotoxicity of self-adhesive resin cements, as evidenced by the results observed at 24 h and 7 days of analysis.

Efeito do peróxido de carbamida e do flúor neutro sobre a superfície do esmalte / Effect of carbamide peroxide and neutral fluoride on enamel surface

This study evaluated the effect of a 10% carbamide peroxide gel on enamel surface and the remineralizing capacity of neutral fluoride applied either during or after bleaching treatment. Sixteen fragments were obtained from four extracted human teeth (incisors and molars) and assigned to four groups. Group I served as the control and groups II, III and IV underwent daily 8-hour carbamide peroxide bleaching treatment for 2 weeks. Additionally, group III was treated with 2% neutral fluoride gel for 4 minutes/day, and group IV received one single application of fluoride gel at the end of the 2-week bleaching treatment. Specimens were examined under scanning electron microscopy (SEM). Micrograph analysis showed that the bleaching gel caused changes to the enamel surface and that the application of neutral fluoride gel during or after treatment did not completely reverse the changes caused by bleaching. Carbamide peroxide increased enamel porosity. Application of neutral fluoride gel during or after the treatment did not produce any significant decrease in enamel porosity. Total enamel recovery seems to be more strongly associated with the buffering properties of saliva than with the use of different fluoride application protocols.

Este estudo avaliou o efeito de um gel de peróxido de carbamida a 10% sobre a superfície do esmalte e a capacidade de remineralização da aplicação de flúor neutro durante e após o tratamento de clareamento. Dezesseis fragmentos foram obtidos de quatro dentes humanos extraídos (incisivos e molares) e distribuídos em quatro grupos. O grupo I serviu como controle, e os grupos II, III e IV foram submetidos a 8 horas diárias de clareamento com peróxido de carbamida durante 2 semanas. O grupo III foi tratado com gel de flúor neutro a 2% por 4 minutos diariamente, e o grupo IV recebeu uma aplicação de flúor ao final de 2 semanas de tratamento clareador. Os espécimes foram examinados sob microscopia eletrônica de varredura (MEV). A análise das fotomicrografias mostrou que o gel clareador causou alterações na superfície do esmalte e que a aplicação do gel de flúor neutro durante ou após o tratamento clareador não reverteu completamente as alterações causadas pelo procedimento clareador. O peróxido de carbamida aumentou a porosidade do esmalte. A aplicação de gel de flúor neutro durante ou depois do tratamento não produziu um aumento significativo na porosidade do esmalte. A recuperação total do esmalte parece estar mais associada com a capacidade tampão da saliva do que com o uso de diferentes protocolos de aplicação de flúor.

Estudo comparativo in vitro da eficácia de clareadores para uso em moldeiras e em consultório / In vitro comparative study on the efficacy of home and in-office techniques

O presente estudo tem como objetivo determinar qual a técnica mais eficaz de clareamento dos dentes vitalizados, considerando a existência de diferentes técnicas. Foram comparados os resultados obtidos com clareamento em consultório e com moldeiras. Um colorímetro (Hunter Lab modelo Ultrascan XE - Hunter Associates Laboratory Inc, Reston, VA) foi empregado para o registro tridimensional e numérico da cor. Nesta pesquisa foram utilizados o peróxido de carbamida a 15%, Opalescence PF (Ultradent Products Inc, South Jordan, UT), e peróxido de hidrogênio a 35%, Opalescence Xtra (Ultradent Products Inc, South Jordan, UT) - fotoativado, seguindo as normas do fabricante. Trinta e nove amostras foram divididas em 3 grupos: grupo 1 - peróxido de carbamida a 15% (técnica caseira), grupo 2 - peróxido de hidrogênio a 35% (técnica em consultório) e grupo 3 - controle. O resultado final foi obtido pela média de variação do primeiro, segundo e terceiro grupo, determinando - numericamente - qual técnica de clareamento é mais eficaz. As técnicas caseira e supervisionada demonstraram mudanças significativas de cor. Foi concluído que o clareamento vital caseiro com peróxido de carbamida a 15%, e o clareamento vital em consultório utilizando peróxido de hidrogênio a 35% fotoativado, são estatisticamente equivalentes. Sendo assim, é possível afirmar que a escolha por uma ou outra técnica deverá ser baseada na particularidade de caso, e no domínio da técnica pelo profissional.

The purpose of this study is to determine the most effective bleaching technique of vital teeth, considering the existence of different techniques. Results obtained from one in-office bleaching agent were compared to those obtained from an at-home material. A colorimeter was used for tri-dimensional and numerical registration of the color. The products used in this investigation were 15 percent carbamide peroxide and 35 percent light-activated hydrogen peroxide, following manufacturer's instructions. Thirty nine samples were divided into 3 groups: group 1 - 15 percent carbamide peroxide (at-home technique), group 2 - 35 percent hydrogen peroxide (in-office technique) and group 3 - control. The most effective bleaching technique was determined by averaging the values found for the three groups. The teeth bleached with the in-office and at-home techniques demonstrated significant changes in color. The results showed that the at-home vital bleaching with 15 percent carbamide peroxide and the in-office vital bleaching using 35 percent light-activated hydrogen peroxide are statistically equivalent. Thus, the choice for one or the other technique can be based on each case individually, since the results will be similar with both tested products.

Camouflage treatment for class III malocclusion combined with traction of an impacted maxillary central incisor.

This case report describes the treatment of a patient with an unerupted maxillary left central incisor, class III malocclusion with crossbite of the maxillary posterior teeth and lateral open bite. Treatment consisted of rapid maxillary expansion followed by anterior space opening, maxillary protraction and traction of the unerupted teeth with a light force system. Favorable results were obtained in terms of correcting incisor position and class III malocclusion. The results achieved remained stable throughout a 4-year retention period.

Restoration of occlusal vertical dimension in dental erosion caused by gastroesophageal reflux: case report.

The authors describe a minimally invasive procedure for occlusal rehabilitation in a young patient presenting with mild mandibular prognathism and loss of occlusal vertical dimension caused by dental erosion from chronic gastroesophageal reflux.

Scanning electron microscopy evaluation of the hard tissue barrier after pulp capping with calcium hydroxide, mineral trioxide aggregate (MTA) or ProRoot MTA.

The aim of this study was to investigate the morphology and localisation of calcium hydroxide- and mineral trioxide aggregate (MTA)-induced hard tissue barriers after pulpotomy in dogs' teeth. Pulpotomies were performed on maxillary and mandibular premolars of five dogs. The teeth were assigned into three groups according to the pulp-capping agent used. The pulpal wounds were capped with calcium hydroxide (Ca(OH)(2)- control), MTA or ProRoot MTA, and the cavities were restored with amalgam. After a 90-day follow-up period, the dogs were euthanised and the teeth were examined under scanning electron microscopy (SEM). An image-processing and analysis software was used to delimit the perimeters of the root canal area and the hard tissue barrier to determine the percentage of root canal obliteration. SEM data were used to assess the morphology, localisation and extension of the reparative hard tissue barriers. ProRoot MTA was statistically different from MTA and Ca(OH)(2) (P < 0.05) regarding tissue barrier morphology. Localisation data showed that ProRoot MTA was significantly different from Ca(OH)(2) (P < 0.05) and similar to MTA (P > 0.01; P > 0.05). No statistically significant difference (P > 0.01; P > 0.05) was observed between MTA and Ca(OH)(2). A larger number of complete (centroperipheral) hard tissue barriers with predominance of dentinal tubules was observed to the ProRoot MTA when compared with the Ca(OH)(2) group.

Influence of the internal conditioning of indirect restorations of resin composite in relation to microleakage using LEDs and QTH units.

The current study evaluated in-vitro microleakage of indirect composite inlays fixed with flowable composite and resinous cement and cured by LEDs and QTH units, thus modifying the internal conditioning of the inlays. Thirty-two non-carious teeth were selected and 64 cavity preparations were performed in both enamel and cementum. These teeth were divided into four groups: I--Elipar FreeLight appliance and Filtek Flowable composite; II--Ultralux appliance and Filtek Flowable composite; III--Elipar FreeLight appliance and RelyX cement and IV--Ultralux appliance and RelyX cement. The inlays were internally sandblasted with aluminum oxide, etched with 37% phosphoric acid, washed and silanized. The dental etching was carried out with 37% phosphoric acid for 15 seconds in dentin and 30 seconds in enamel. After being washed and dried, Single Bond dentinal adhesive was then applied, and the inlays were fixed with their respective luting agents, cured in close contact with their surfaces for 60 seconds, thermocycled and immersed in 0.5% basic fuchsine solution. The teeth were then washed and sectioned through the center of the restoration in order for the microleakage readings to be performed using the Image Tool Software. Then, ANOVA and Tukey's statistical tests were applied. In enamel, there was no significant difference for both groups with regard to microleakage; in cementum, the significant difference was 5% (p > 0.005). In agreement with the results, the inlays can be fixed with RelyX and Filtek Flowable resins.

Efeito da intensidade de luz, distância e tempo de fotoativação sobre a interface esmalte-resina composta: análise por microscopia eletrônica de varredura / Effect of light intensity, distance and curing time on resin-composite to enamel adaptation: analysis by scanning electronic microscopy

O objetivo deste estudo foi analisar por microscopia eletrônica de varredura (MEV) a adaptação esmalteresinacomposta, variando intensidade de luz, tempo de fotoativação e distância da ponteira à resina. Foram confeccionadas 48 cavidades (2,2 mm de diâmetro e 4mm de profundidade) nas superfícies vestibular, lingual, mesial e distal de 12 molares extraídos. As cavidades (n= 48) foram restauradas em incremento único com resina composta (Supreme®), fotoativadas observando os fatores: 180 ou 580 mW.cm-2, 20 ou 40s de fotoativação, ponteira justaposta à resina ou afastada 8 mm. Os grupos estão descritos como: G1 - 20s x 180 mW.cm-2 x 0 mm; G2 - 40s x 180 mW.cm-2 x 0 mm; G3 - 20s x 580 mW.cm-2 x 0 mm; G4 - 40s x 580 mW.cm-2 x 0 mm; G5 - 20s x 180 mW.cm-2 x 8 mm; G6 - 40s x 180mW.cm-2 x 8 mm; G7 - 20s x 580 mW.cm-2 x 8 mm; G8 - 40s x 580 mW.cm-2 x 8 mm. As cavidades restauradas foram preparadas para serem analisadas em MEV a fim de se observar a adaptação adesiva. Por meio dos resultados do teste não paramétrico de Kruskal-Wallis (α = 0,05), verificou-se que existe diferença significativaentre os grupos. Observou-se que os grupos 1, 2, 5 e 6 apresentaram melhor adaptação que os grupos 3, 4 e 7. O grupo 8 não apresentou diferença significativa em relação aos demais grupos. Na comparação entre os grupos, as menores desadaptações evidenciaram-seao se trabalhar com baixa intensidade da fonte de luz.O tempo de ativação e a distância da fonte à resina não tiveram influência na adaptação das restaurações

Microdureza de resina composta polimerizada com LEDs de diferentes gerações e luz halógena / Microhardness test of composite resin cured by two different LED and one halogen units

O desempenho clínico das restaurações de resina composta (RC) está diretamente relacionado com a qualidade da polimerização obtida através dos aparelhos fotopolimerizadores. O propósito deste estudo foi avaliar a microdureza de uma RC polimerizada com três diferentes fontes de luz, comparando-as entre si. Foram utilizados os aparelhos de luz halógena convencional [Visilux 2 - 3M] (A), um LED de primeira geração [Optilight Plus- Gnatus] (B), e um LED de terceira geração [Radii-SDI] (C). Foram confeccionados trinta corpos de prova utilizando a RC Filtek Z250 (3MESPE), dividindo-os em três grupos. As amostras foram submetidas ao teste de microdureza Vickers nas superfícies de topo e base. Os resultados estatísticos mostraram que as amostras do grupo B apresentavam os menores valores, tanto na base quanto no topo (p<0,01). Conclui-se que, entre os LEDs estudados, o Radii mostrou os melhores resultados de microdureza, sendo semelhantes ao aparelho de luz halógena.

Clinical performance of composite resins is closely related to the quality of the polymerization process. The purpose of this study was to evaluate the microhardness of a composite resin when polymerized by three different light sources (Conventional/halogen – Visilux2, 3M; First generation LED – Optilight Plus, Gnatus and Third generation LED – Radii, SDI). Thirty samples were prepared made of Filtek Z250 A2 composite resin (3M-Espe) and divided into three groups. Samples were subjected to microhardness test and results shown in Vickers scale, at the top and the bottom of each sample. Statistical analysis showed that samples cured with fi rst generation LED presented the lowest values for Vickers hardness, either at the top or the bottom. In conclusion, it is possibleto observe that third generation LED and halogen lamps are effective as curing units, presenting similar results in microhardness tests.

Orthodontic space closure of lost traumatized anterior teeth - case report.

This case report refers to an 11-year-old boy with avulsion of the upper left central and lateral incisors. The teeth were replanted after 4 h, splinted with a semi-rigid splint for 12 days, and then endodontically treated. Severe progressive root resorption was seen after 2 years and the teeth were extracted. The boy had a normal occlusion with spacing in both jaws and slight protrusion of the anterior teeth. The treatment objectives were to close some of the spaces by mesial movement of the buccal segments in the upper jaw to minimize bone loss for a future single osseointegrated implant. Fixed appliance in combination with a removable plate was used for the mesial movements, levelling, and alignment of the upper jaw. Fixed appliance in the lower jaw and Class II traction were used for the final adjustment of the occlusion. A good occlusion with coincident upper and lower midlines and up-righted anterior teeth were achieved. A Maryland bridge was performed as a temporary solution for a future osseointegrated implant.

Repairing ceramic restorations: final solution or alternative procedure?

This article provides an overview of dental ceramics. It addresses possible modes of failure and factors that may influence the decision to either repair or replace ceramic restorations. The authors' intention was to present ceramic repair as a reliable, low-cost, low-risk technique.