Avaliação clínica de inlays e onlays confeccionadas com dois tipos de cerâmica, após 06 meses

The aim of the present study was to evaluate the clinical performance of two types of ceramics: a slurry-powder ceramic (Duceram Plus, Degussa) - D and a hot-pressed leucite-based glass-ceramic (IPS Empress, Ivoclar Vivadent) - IPS. Eighty-six restorations, 44 IPS and 42 D, were made by one operator. A total of 33 onlays and 53 inlays on twenty-seven premolars and 59 molars were cemented in 35 patients of both sexes, mean age 35 years. All restorations were cemented with the dual-resin cement (Variolink, Ivoclar-Vivadent) under rubber dam and were evaluated at the baseline and after six months, using the modified U.S.P.H.S. criteria for postoperative sensitivity, secondary caries, fracture, color match, marginal discoloration, marginal integrity and surface texture. Additionally radiographs and intraoral photographs were carried out. At baseline 86 restorations were analyzed and all of them received Alfa rating, except for the following that received Bravo rating for postoperative sensitivity - IPS (2.27%); D (7.14%); for color match - IPS (2.27%); D (2.38%) and for surface texture - IPS (2.27%); D (11.90%). After 6 months 100% of the restorations were analyzed and the following received Bravo rating: color match - IPS (4.55%) and D (9.52%); surface texture - IPS (2.27%) and D (11.9%); marginal discoloration - IPS (6.82%) and D (4.76%) and marginal integrity - IPS (4.55%) and D (7.14%). The results were submitted to the Fisher and McNemar Statistical Tests. No significant differences were noticed between the two ceramics. Both ceramics demonstrated satisfactory clinical performance after six months.Este trabalho se propôs a avaliar a performance clínica de dois tipos de cerâmica: IPS Empress, Ivoclar-Vivadent - IPS e Duceram Plus, Degussa - D. Foram realizadas 86 restaurações por apenas um operador, sendo 44 IPS e 42 D. Vinte e sete pré-molares e 59 molares, num total de 33 onlays e 53 inlays, foram cimentadas em 35 pacientes de ambos os sexos, com idade média de 35 anos. A cimentação das restaurações foi realizada com cimento resinoso dual (Variolink, Ivoclar-Vivadent) sob isolamento absoluto e avaliadas no baseline e após 06 meses, mediante o critério U.S.P.H.S. modificado, quanto à sensibilidade pulpar, reincidência de cárie, fratura, reprodução de cor, descoloração marginal, integridade marginal e textura superficial. Adicionalmente foram realizadas radiografias e fotografias. No baseline foi obtida a classificação Bravo nos itens sensibilidade pulpar - IPS (2,27%); D (7,14%); reprodução de cor - IPS (2,27%); D (2,38%) e textura superficial - IPS (2,27%); D (11,90%). Após 06 meses foram analisadas as 86 restaurações, nas quais foi constatada a classificação Bravo para os itens reprodução de cor - IPS (6,82%); D (2,38%); textura superficial - IPS (2,27%); D (9,52%); descoloração marginal - IPS (6,82%); D (4,76%) e integridade de superfície- IPS (4,55%); D (7,14%). Os resultados obtidos foram submetidos ao Teste Estatístico de Fisher e McNemar. Não houve diferença estatisticamente significante entre as cerâmicas. Pode-se concluir que os dois tipos de cerâmica demonstraram uma performance clínica satisfatória após 06 meses

Diametral tensile strength of a resin composite core bonded to prefabricated posts.

Este estudo teve a finalidade de verificar influência de diferentes tipos de pinos intra-radiculares sobre a resistência à fratura de um material restaurador coronário, utilizando o teste de tração diametral. Foram confeccionados 70 corpos de prova divididos em 7 grupos: G1. Compósito (Tetric Ceram Ivoclar/Vivadent) (Grupo Controle); G2. Compósito e pino VectrisPost (Ivoclar/Vivadent); G3. Compósito e pino Fiber-Post (Jeneric/Pentron); G4. Compósito e pino Æstheti-Plus (Bisco); G5. Compósito e pino Light-Post (Bisco); G6. Compósito e pino Dentorama (Svenska) e G7. Compósito e pino ParaPost (Còltene/Whaledent). Todos os grupos foram submetidos ao ensaio de tração diametral em uma máquina de ensaios Instron, modelo 8501, até a fratura. A média dos grupos em MPa foi: G 1- 49,64 (3,36); G 2- 29,77 (3,36); G 3- 31,9 (2,39); G 4- 28,92 (2,20); G 5- 34,26 (3,37); G 6-33,45 (2,46) e G 7- 27,90 (2,40). A análise estatística dos dados nos permitiu concluir que: os pinos utilizados não reforçaram a resina composta; os pinos Light-Post, Dentorama e Fiber-Post apresentaram os melhores valores de adesividade ao material de reconstrução coronária e que o pino metálico ParaPost apresentou o menor valor de adesão à resina de reconstrução coronal.The purpose of this study was to determine the influence of different types of posts on the fracture strength of a resin composite core material using the diametral tensile strength test. Seven groups of specimens were prepared each with 10 cylindrical specimens made of one composite material (Tetric Ceram, IvoclarVivadent) as follows: Group 1- Control group of composite only specimens; Group 2-Composite and VectrisPost (IvoclarVivadent); Group 3- Composite and Fiber-Post (Jeneric/Pentron); Group 4- Composite and Æstheti-Plus post (Bisco); Group 5- Composite and Light-Post (Bisco); Group 6- Composite and Dentorama post (Svenska) and group 7- Composite and ParaPost (Coltene/Whaledent). Following storage specimens were subjected to compressive loading in an Instron testing machine (model 8501) until failure occurred. Means and standard deviations of diametral tensile strengths in MPa were: Group 1- 49,64 (3,36); Group 2- 29,77 (3,36); Group 3- 31,9 (2,39); Group 4- 28,92 (2,20); Group 5- 34,26 (3,37); Group 6- 33,45 (2,46) and Group 7- 27,90 (2,40). Statistical analysis revealed significant differences in mean diametral tensile strengths among the groups. It is concluded that the use of posts did not reinforce the composite resin cores. Among the post/core groups Light-Post, Dentorama post and Fiber-Post resulted in the highest values of tensile strength while ParaPost resulted in the lowest value of tensile strength

Accuracy of mechanical torque devices for implants used in Brazilian dental offices

The purpose of this study was to determine the accuracy of mechanical torque devices in delivering target torque values in dental offices in Salvador, Brazil. A team of researchers visited 16 dental offices, and the clinicians applied torque values (20 and 32 Ncm) to electronic torque controllers. Five repetitions were completed at each torque value and data were collected. When 20 Ncm of torque was used, 62.5% of measured values were accurate (within 10% of the target value). For 32 Ncm, however, only 37.5% of these values were achieved. Several of the tested mechanical torque devices were inaccurate. © 2011 by Quintessence Publishing Co Inc

Adhesive Cementation of Etchable Ceramic Esthetic Restorations

This article describes the different materials and techniques that are used for adhesive cementation. Particular attention is given to treatments suitable for dentin, as well as the selection of surface treatments for various restorative materials. Factors related to the durability and stability of the adhesive process, as well as the clinical and laboratory procedures required for cementation, are also discussed

Retrospective clinical evaluation of ceramic onlays placed by dental students.

STATEMENT OF PROBLEM: Indirect restorations with partial or complete occlusal surface coverage have been recommended to restore teeth with weakened walls in order to prevent cusp fracture. The success of these restorations when performed by dental students is unknown. PURPOSE: The purpose of this retrospective study was to evaluate the clinical performance of adhesively bonded ceramic onlay restorations placed by third- and fourth-year dental students. MATERIAL AND METHODS: Sixty-five ceramic onlays were placed in patients between 2009 and 2015. The onlays were laboratory or chairside fabricated with a computer-aided design and computer-aided manufacturing (CAD-CAM) system, using either IPS e.max Press or IPS e.max CAD. An adhesive technique and luting composite resin agent were used to cement the restorations. Thirty-seven onlays were evaluated clinically using the modified United States Public Health Service (USPHS) criteria. Data were statistically analyzed using the Cox proportional hazards model to compare tooth type and failures and the Fisher exact and McNemar tests to compare the USPHS criteria for significant differences (α=.05). Survival probability was calculated using the Kaplan-Meier algorithm. RESULTS: Five onlays were considered to be failures and needed replacement. According to the Kaplan-Meier analysis, the estimated survival rate was 96.3% after 2 years and 91.5% at 4 years. All 5 of the failures occurred on molars (13.5%) and none on premolars (P=.025). A statistically significant difference was found for marginal discoloration between onlays placed within 0 to 3 years and 3 to 6 years (P CONCLUSIONS: Ceramic onlays placed by dental students demonstrated acceptable long-term clinical performance

CAD/CAM technology and esthetic dentistry: a case report.

Advances in dental materials as well as in computer technology have made CADCAM-fabricated restorations not just possible in dentistry but plentiful. When using CADCAM systems, operators can fabricate restorations from several materials, including ceramics, metal alloys, and various composites. This case report describes the replacement of a porcelain-layered zirconia-based (coping) crown on a left lower cuspid that presented with a veneering ceramic chipping on a lithium-disilicate CADCAM-fabricated crown. It demonstrates how all-ceramic systems offer a promising alternative in the restoration of anterior teeth

Influence of the fabrication technique on the marginal and internal adaptation of ceramic onlays

This study aimed to evaluate the marginal and internal adaptation of partial coverage crowns (ceramic onlays) fabricated with Press, CEREC BlueCam, and CEREC OmniCam systems, using two preparation designs and evaluating the internal discrepancies at different locations. Two phantom maxillary premolars (master teeth) received different preparation designs, with (BX) and without (NB) a modified occlusal box with round internal angles. Sixty IPS e-max ceramic restorations were fabricated with three systems: Press (n=20), CEREC BlueCam (n=20), and CEREC OmniCam (n=20). Both marginal and internal discrepancy width were measured by using a stereomicroscope at 325 magnification. The data were evaluated statistically using analysis of variance followed by Tukey\u27s Honestly Significant Difference test (a=0.05). The ceramic restorations fabricated with the Press system presented significantly smaller marginal and internal disadaptations than the BlueCam and OmniCam CEREC systems (p,0.0001). Regarding the preparation designs, preparation BX presented the smallest marginal discrepancies for all fabrication systems and larger internal discrepancies than for restorations fabricated with the Press system. The occlusal location presented a larger internal discrepancy compared with the axial locations. Although the three systems resulted in the fabrication of restorations within a clinically acceptable adaptation with marginal discrepancies below 100 lm, the Press system presented the smallest marginal and internal discrepancies. An improved marginal adaptation was observed in the preparation design with a modified occlusal box with rounded internal angles

Microleakage and microtensile bond strength of silorane-based and dimethacrylate-based restorative systems.

To evaluate the microleakage and bond strengths (microTBS) of silorane-based (SBC) and dimethacrylate-based (DBC) restorative systems. The null hypotheses are: 1) there is no difference in microleakage between the resin composites and the adhesive systems tested at the enamel and dentin margins; 2) there is no significant difference in microTBS between the composite restorative systems using self-etch and etch-and-rinse adhesive versions. Microleakage: Class V cavity preparations with cervical margin in dentin were performed on pristine extracted human molars and were randomly distributed among the following three groups: Group 1-DBC/etch-and-rinse adhesive system (Filtek™ Supreme Ultra/Adper™ Single Bond Plus, 3M ESPE, www.3MESPE.com); Group 2-SBC/self-etch adhesive (Filtek LS Low Shrink Posterior Restorative System/LS self-etch adhesive, 3M ESPE); Group 3-DBC/self-etch adhesive (Filtek Supreme Ultra/ Adper Easy Bond Self-Etch, 3M ESPE). Restorations were thermocycled and immersed in 0.2 percent methylene blue dye for 24 hours. Samples were assessed visually under 10x magnification; microTBS: Bond sticks (0.9 mm2) were prepared from each group and tested on a universal testing machine. The Kruskal-Wallis test revealed no significant difference in microleakage among the experimental groups at the enamel margin (P=0.191). At the dentin margins, silorane/self-etch restorative system showed significantly less leakage than the dimethacrylate/etch-and-rinse restorative system (P=0.008). Tukey\u27s B rank order test showed that the dimethacrylate/etch-and-rinse restorative system presented the highest microTBS. SBC/self-etch system showed less microleakage at the dentin margins, while DBC/etch-and-rinse system presented higher bond strength

Hardening of dual-cure resin cements and a resin composite restorative cured with QTH and LED curing units

Objective: The aim of this study was to determine the effects of light intensity and type of light unit (quartztungsten-halogen [QTH] or light-emitting diode [LED]) on the hardening of various resin cements and a resin composite restorative. Methods: Disk specimens were prepared from 4 dual-cured resin cements (Variolink II, Calibra, Nexus 2 and RelyX ARC). Two QTH light-curing units (Visilux 2, at 550 mW/cm , and Optilux 501, at 1,360 mW/cm ) and a LED unit (Elipar FreeLight, at 320 mW/cm ) were used for curing. Specimens were light-cured or dual-cured for W, 30 or 40 seconds with 1 of the 3 light units (curing applied to upper surface only) and were tested 24 hours after curing. Additional cement specimens were self-cured and tested at 15, 30 and 60 minutes and at 24 hours. Testing consisted of measurement of Knoop hardness number (KHN) for each specimen. Six KHN values were obtained for the upper surface only of the various cement specimens in each test group. Disk specimens 2.5 mm thick were also prepared from a resin composite restorative (XRV Herculite). These were light-cured as above, and KHN measurements were obtained for both the upper and the lower surfaces. Mean KHNs were determined, and data were analyzed with analysis of variance. Results: The groups were significantly different (p \u3c 0.05). High-intensity light curing resulted in the highest KHN values for all materials with any of the 3 light-curing times. For the cements, LED light curing (with both dual-curing and light-curing modes) resulted in hardness values similar to those achieved with conventional QTH light curing, although there were some exceptions. However, both LED and conventional QTH light curing resulted in inferior hardening of lower surfaces of the XRV Herculite specimens at the 3 curing times. For all cements except Nexus 2, self-curing resulted in significantly lower hardness values than dual curing. The self-curing mechanism of Variolink II cement needed a longer time to activate than those of the other cements. Conclusions: High-intensity light curing and longer curing times resulted in the highest KHNs. The LED curing unit was associated with the lowest hardness values for lower surfaces of the resin composite restorative. © J Can Dent Assoc 2004. 2 2