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STATEMENT OF PROBLEM: The type of veneer preparation is often chosen according to the patient's tooth structure and occlusion. Taking biomechanics into account in this decision-making process provides the clinician with more technical information on how to improve the clinical longevity of restorations. However, biomechanical analyses of veneer preparation designs are sparse. PURPOSE: The purpose of this 3-dimensional (3D) finite element analysis with microcomputed tomography (µCT) data obtained from realistic models was to assess the influence of different preparations for ceramic and composite resin veneers on restoration and resin layer stress distribution. MATERIAL AND METHODS: Four replicas of a central incisor were printed and prepared for laminate veneers with 4 different incisal edge designs: shoulder (SH), palatal chamfer (PC), palatal chamfer and oblique fracture involving the distal angle (OF-PC), and palatal chamfer involving horizontal incisal fracture (IF-PC). After fabrication and cementation of the veneers, the restored replicas were assessed with µCT, and 3D finite element models were built. A 100-N load was applied on the palatal surface at 60 and 125 degrees relative to the longitudinal axis. Maximum principal stress and stress distribution on the veneers, cement layer, and tooth structure were calculated and analyzed. RESULTS: The SH preparation exhibited better stress distribution than the PC preparation, and the cement layer and the veneer were subjected to lower stress. The IF-PC preparation had better stress distribution than the OF-PC. The shoulder and IF-PC showed higher stress on laminate veneers, but lower stress on the cement layer. Ceramic veneers exhibited lower stress than composite resin veneers. CONCLUSIONS: The different incisal preparations for laminate veneers influenced stress distribution on restorations and on the resin cement layer. The shoulder type preparation showed better stress distribution and the composite resin veneers showed unfavorable results compared with the ceramic veneers.

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OBJECTIVES: Nowadays, it is believed that more than 240 million people worldwide are infected with the hepatitis B virus (HBV), associated with irreversible health-related consequences, represented by hepatic failure, cirrhosis, and hepatocellular carcinoma, and already are ranked as 15th cause of human death around the world. METHODS: A systematic review and a meta-analysis were performed to evaluate the effectiveness of vaccination and immunization on health professionals against HBV. The review was registered at the PROSPERO database (CRD42017075643). A search for cross-sectional studies was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and in the gray literature. The Effective Public Health Practice Project Modified Scale was used to evaluate the internal quality of the studies included. RESULTS: A total of 1865 articles were identified after the removal of duplicates. Of these, 790 studies remained after screening the titles and abstracts. Finally, ten studies remained after full-text reading for qualitative analysis, all of which were used in the meta-analysis. A significant difference was found in the vaccine protocol for health professionals immunized against hepatitis B, compared to those not immunized. The risk ratio was 7.37 (95% confidence interval = 3.92-13.83; P < 0.00001). CONCLUSION: This study showed that the vaccine protocol is effective in immunizing health professionals against hepatitis B.

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The aim of this research was to evaluate the influence of MDP (10-methacryloyloxydecyl dihydrogen phosphate) concentration and application mode of experimental adhesives on microshear bond strength (µSBS) to dentin after storage in distilled water at 37°C for 24h and 6 months. Five experimental adhesives were prepared with: CQ, DABE, BHT, ethanol, HEMA, TEGDMA, Bis-EMA, UDMA, and Bis-GMA. Concentrations of 0 wt%, 3 wt%, 9 wt%, 12 wt% or 15 wt% of MDP were added to their composition. The adhesives were applied to flat dentin surfaces in etch-and-rinse or self-etching modes. Cylindrical molds filled with light-cured composite resin were placed above the dentin. The specimens were stored in distilled water at 37oC for 24h or 6 months and submitted to µSBS testing. The adhesives were also submitted to pH analysis. The data were analyzed by one-way ANOVA, three-way ANOVA and Tukey's test (α = 5%). All the adhesives used in the etch-and-rinse mode showed significantly higher bond strength than the adhesives applied in the self-etching approach. The 9 wt% adhesive showed the highest bond strength values, and 3 wt% was most stable after storage. A strong negative correlation between MDP concentration and pH was observed. It was concluded that the formulations with low concentrations of MDP (up to 9 wt%) showed better results for bond strength and bond strength degradation over time.

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RESUMO Introdução: O uso de próteses totais tem impacto na qualidade de vida relacionada à saúde bucal e os idosos são uma parcela da população a ser pesquisada sob essa perspectiva. Objetivo: Avaliar a autopercepção do impacto do uso de próteses totais na qualidade de vida relacionada à saúde bucal de idosos institucionalizados. Métodos: Participaram 20 idosos do Lar dos Idosos Recanto do Tarumã, Curitiba, Paraná, Brasil. Foram avaliados aspectos demográficos, econômicos, de hábitos e clínicos, juntamente com aplicação do questionário Geriatric Oral Health Assessment Index. Os dados foram submetidos à análise descritiva e bivariada (Teste do Qui-Quadrado), com significância de 5 porcento. Resultados: A média de idade foi de 75,2 anos (DP= 8,8) e o tempo médio de uso de prótese foi de 27,9 anos (DP= 18,5). Renda inferior a um salário mínimo foi indicada por 80,0 porcento, e visitas ao cirurgião-dentista pela última vez há mais de um ano, por 70,0 porcento. Os piores relatos foram referentes à mastigação, representados por problemas para mastigar alimentos e desconforto ao comer, com 25 porcento de respostas positivas em cada questão; a soma das frequências das respostas "às vezes" e "sempre" quanto à insatisfação ou à infelicidade com a aparência da boca foi reportada 60 porcento dos pesquisados. A retenção insatisfatória da prótese inferior se deu em 50,0 porcento casos, enquanto os problemas com oclusão estiveram presentes também em metade da amostra. Os defeitos estiveram presentes em 70,0 porcento das próteses superiores e 45,0 porcento das inferiores. Não foi encontrada associação significativa (p> 0,05) entre as variáveis independentes e o desfecho. Conclusões: Os idosos avaliados, independentemente das condições das próteses totais, relataram qualidade de vida relacionada à saúde bucal satisfatória(AU)

RESUMEN Introducción: El uso de prótesis totales tiene un impacto en la calidad de vida relacionada con la salud bucal, y los ancianos son parte de la población que se investigará desde esta perspectiva. Objetivo: Evaluar la autopercepción del impacto del uso de prótesis totales en la calidad de vida relacionada con la salud bucal de ancianos institucionalizados. Métodos: Participaron 20 ancianos de "Lar dos Idosos Recanto do Tarumã", Curitiba, Paraná, Brasil. Los aspectos demográficos, económicos, de hábitos y clínicos se evaluaron junto con la aplicación del cuestionario Geriatric Oral Health Assessment Index. Los datos fueron sometidos a análisis descriptivo y bivariado (prueba de chi cuadrado), con significación del 5 por ciento. Resultados: La edad media fue de 75,2 años (DE= 8,8) y el tiempo medio de uso de la prótesis fue de 27,9 años (DE= 18,5). Los ingresos menores a un salario mínimo se indicaron en el 80,0 por ciento, y las visitas al cirujano dental la última vez, hace más de un año, en el 70, 0 por ciento. Los peores informes estaban relacionados con la masticación, representados por problemas para masticar los alimentos y la incomodidad al comer, con el 25 por ciento de respuestas positivas en cada pregunta. La suma de las frecuencias de las respuestas "a veces" y "siempre" sobre la insatisfacción o la infelicidad con la apariencia de la boca se informó en el 60 por ciento de los encuestados. La retención insatisfactoria de la prótesis inferior se produjo en el 50 por ciento de los casos, mientras que la oclusión también presentó problemas en la mitad de la muestra. Los defectos estuvieron presentes en el 70,0 por ciento de las prótesis superiores y en el 45,0 por ciento de las inferiores. No se encontró asociación significativa (p> 0,05) entre las variables independientes y el desenlace. Conclusiones: Los ancianos evaluados, independientemente de las condiciones de las prótesis totales, informaron una calidad de vida relacionada con la salud bucal satisfactoria(AU)

ABSTRACT Introduction: The use of complete dentures has an impact on oral health-related quality of life. Elderly people are the population sector to be researched into from this perspective. Objective: Evaluate the self-perception of the impact of the use of complete dentures on the oral health-related quality of life of institutionalized elderly people. Methods: The study sample was 20 elderly people from Lar dos Idosos Recanto do Tarumã, Curitiba, Paraná, Brazil. Evaluation of demographic and economic details, habits and clinical aspects was based on the information collected with the Geriatric Oral Health Assessment Index questionnaire. The data were subjected to descriptive and bivariate analysis (Chi-squared test), with a significance of 5 percent. Results: Mean age was 75.2 (SD = 8.8) years and mean time of denture use was 27.9 (SD = 18.5) years. Income was below minimum wage in 80.0 percent of the participants, whereas the last visit to the dentist had occurred more than a year ago in 70.0 percent. The worst reports had to do with chewing, represented by problems to chew food and discomfort when eating, with 25 percent positive answers to each question. The sum of the frequencies of the answers "sometimes" and "always" about dissatisfaction with or unhappiness about the appearance of the mouth was reported by 60 percent of the respondents. Unsatisfactory retention of the lower denture occurred in 50.0 percent of the cases, whereas occlusion problems were present in half of the sample. Defects were present in 70.0 percent of the upper dentures and 45.0 percent of the lower dentures. No significant association (p> 0.05) was found between independent variables and outcome. Conclusions: The elderly people evaluated, regardless of the conditions of their complete dentures, reported satisfactory oral health-related quality of life(AU)

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The objective of this systematic review was to compare the conical internal connection (IC) with the external hexagonal connection (EH) on the occurrence of marginal bone loss (ΔMBL). Different databases were used to carry out the selection of the elected studies. The studies were judged according to the risk of bias as "high", "low" and "unclear" risk. For the meta-analysis we included only studies that could extract the data of ΔMBL, survival rate (SR) and probing depth (PD). No statistically significant differences were found for ΔMBL data at one, three- and five-year survival rates between implant connections (p <0.05), however statistically significant differences were found for PD between EH and IC implants (1-year follow-up) -0.53 [95%CI -0.82 to -0.24, p = 0.0004]. This present systematic review demonstrated that there are no significant differences between IC and EH implants for both ΔMBL and SR at 1, 3 e 5 years after functional loading, although better PD values were observed for implants pertaining to the IC connections. Considering the high heterogeneity, more well-delineated, randomized clinical trials should be conducted.

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Direct composite resin restorations are commonly provided because of their satisfactory esthetics and minimal wear of opposing tooth structure. Recent restorative systems may not follow the nomenclature of the classical VITA shade guide, using instead a simplified resin color system. A better understanding of these systems and their behavior regarding the incidence of light is an excellent approach to anterior restorations, especially for fractured anterior teeth. This paper demonstrates the color selection and clinical sequence for the natural reproduction of tooth structure using a resin system that does not follow the VITA classical scale.

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The influence of curing mode and shade of resin cements on the color stability of minimum-thickness ceramic veneers after a three-year storage time in distilled water was evaluated in this study. Ninety-six 0.5-mm-thick feldspathic ceramic veneers (Mark II) were luted onto resin composite substrates (Filtek Z350 XT, shade A2E) with two light-cured (NX3 Light-cure and AllCem Veneer) and dual-cured resin cements (NX3 dual-cure and AllCem) in various shades. The specimens were stored in distilled water at 37°C. Color measurements were performed with a spectrophotometer at the following times: 1h and 24h; 7, 30, and 180 days; and 1, 2, and 3 years. Data for color difference (ΔEab) light-cured and dual-cured resin cements were analyzed by two-way ANOVA with repeated measures and Tukey's test (α = 0.05). For the light-cured cements, the ΔEab values were as follows: NX3-Yellow (2.37±1.35) = ACV-A1 (2.40±1.21) = ACV-Trans (2.52±1.46) = ACV-E-Bleach M (2.56±1.42) = NX3-White (2.69±1.49) = NX3-Clear (2.98±1.68). The lowest ΔE values were found for 1 h (0.61±0.36)a, followed by 24 h (1.15±0.55)b and 30 days (2.48±1.11)c. One year, 180 days, and 2 and 3 years presented higher ΔEab values (3.34±0.94, 3.52±1.04, 3.52±0.95 and 3.55±1.14, respectively)d. For the dual-cured cements, the ΔEab values varied as follows: NX3-Clear (2.32±1.24)a = NX3-Yellow (2.37±1.32)a = NX3-White (2.76±1.43)a < AC-Trans (3.77±1.91)b = AC-A3 (4.13±2.11)b < AC-A1 (5.38±2.92)c. Considering time, the lowest ΔEab values were found for 1 h (0.48±0.25)a, followed by 24 h (2.13 ±0.83)b, 30 days (3.54±1.31)c, and 180 days (3,70±1.73)c. The follow-up times of 1 (4.43±2.15)d, 2 (5.02±1.74)e, and 3 years (4.90±2.12)e presented higher ΔEab values. This study demonstrated that light-cured resin cements were less susceptible to color change than dual-cured cements. After 2 years of follow-up, all cements presented ΔEab values above the acceptability threshold.

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Abstract The objective of this systematic review was to compare the conical internal connection (IC) with the external hexagonal connection (EH) on the occurrence of marginal bone loss (ΔMBL). Different databases were used to carry out the selection of the elected studies. The studies were judged according to the risk of bias as "high", "low" and "unclear" risk. For the meta-analysis we included only studies that could extract the data of ΔMBL, survival rate (SR) and probing depth (PD). No statistically significant differences were found for ΔMBL data at one, three- and five-year survival rates between implant connections (p <0.05), however statistically significant differences were found for PD between EH and IC implants (1-year follow-up) -0.53 [95%CI -0.82 to -0.24, p = 0.0004]. This present systematic review demonstrated that there are no significant differences between IC and EH implants for both ΔMBL and SR at 1, 3 e 5 years after functional loading, although better PD values were observed for implants pertaining to the IC connections. Considering the high heterogeneity, more well-delineated, randomized clinical trials should be conducted.

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INTRODUCTION: Plasmacytoma describes a neoplastic proliferation of plasma cells affecting different groups of patients according to location, and may demonstrate heterogeneous tumor progression and survival rate. The present article describes a case of solitary plasmacytoma in the mandible. PRESENTATION OF CASE: A 57-year-old male smoker was referred to the oral and maxillofacial service with extensive injury, approximately 4-5 cm in size, involving the anterior inferior region of mandible. After confirming diagnosis of plasmacytoma through incisional biopsy, because it was a recurrent lesion, excision of the lesion was performed through marginal resection of the mandible under general anesthesia. During the same surgical procedure, a 2.4-mm system fixation plate was placed to mitigate the risk for pathological fracture of the mandible. In a second surgery, a region in the base of the mandible was rehabilitated using implants and prosthesis. CONCLUSION: The patient is currently undergoing clinical and radiological follow-up of 2 years with success.

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Planning oral rehabilitation that involves an interdisciplinary approach is challenging, especially when it includes changes in the morphologic aspects of teeth and the architecture of gingival tissues. Patients commonly complain about the esthetics of maxillary anterior teeth, especially when diastemata are present. A guideline known as the golden proportion can be used to establish adequate width distribution of anterior teeth. Tooth proportion is also affected by incisogingival tooth length, hence gingival contouring should be evaluated as well. In these situations, the width-to-height ratio of 0.75:0.78 in the maxillary anterior teeth could be used to obtain wax-ups and a surgical guide, resulting in a more predictable esthetic outcome. Therefore, this clinical report describes a protocol for the planning of a periodontal-restorative approach with two wax-ups and a surgical guide using the golden proportion width-to-height ratio of 0.75:0.78 for the treatment of maxillary anterior teeth with diastemata using minimum thickness lithium disilicate veneers.

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The objective of this study was to evaluate the marginal and internal fit of zirconia copings obtained with different digital scanning methods. A human mandibular first molar was set in a typodont with its adjacent and antagonist teeth and prepared for an all-ceramic crown. Digital impressions were made using an intraoral scanner (3Shape). Polyvinyl siloxane impressions and Type IV gypsum models were also obtained and scanned with a benchtop laboratory scanner (3Shape D700). Ten zirconia copings were fabricated for each group using CAD-CAM technology. The marginal and internal fit of the zirconia copings was assessed by the silicone replica technique. Four sections of each replica were obtained, and each section was evaluated at four points: marginal gap (MG), axial wall (AW), axio-occlusal edge (AO) and centro-occlusal wall (CO), using an image analyzing software. The data were submitted to one-way ANOVA and Tukey's test (α = 0.05). They showed statistically significant differences for MG, AO and CO. Regarding MG, intraoral scanning showed lower gap values, whereas gypsum model scanning showed higher gap values. Regarding AO and CO, intraoral digital scanning showed lower gap values. Polyvinyl siloxane impression scanning and gypsum model scanning showed higher gap values and were statistically similar. It can be concluded that intraoral digital scanning provided a lower mean gap value, in comparison with conventional impressions and gypsum casts scanned with a standard benchtop laboratory scanner.

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Abstract The objective of this study was to evaluate the marginal and internal fit of zirconia copings obtained with different digital scanning methods. A human mandibular first molar was set in a typodont with its adjacent and antagonist teeth and prepared for an all-ceramic crown. Digital impressions were made using an intraoral scanner (3Shape). Polyvinyl siloxane impressions and Type IV gypsum models were also obtained and scanned with a benchtop laboratory scanner (3Shape D700). Ten zirconia copings were fabricated for each group using CAD-CAM technology. The marginal and internal fit of the zirconia copings was assessed by the silicone replica technique. Four sections of each replica were obtained, and each section was evaluated at four points: marginal gap (MG), axial wall (AW), axio-occlusal edge (AO) and centro-occlusal wall (CO), using an image analyzing software. The data were submitted to one-way ANOVA and Tukey's test (α = 0.05). They showed statistically significant differences for MG, AO and CO. Regarding MG, intraoral scanning showed lower gap values, whereas gypsum model scanning showed higher gap values. Regarding AO and CO, intraoral digital scanning showed lower gap values. Polyvinyl siloxane impression scanning and gypsum model scanning showed higher gap values and were statistically similar. It can be concluded that intraoral digital scanning provided a lower mean gap value, in comparison with conventional impressions and gypsum casts scanned with a standard benchtop laboratory scanner.

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