Influence of cavity design on quality of margin and marginal adaptation and microleakage of all-ceramic CAD/CAM inlays / 北京大学学报(医学版)

OBJECTIVE@#To investigate the influence of 135° and 90° cavity design on quality of margin and marginal adaptation and microleakage of all-ceramic computer aided design/computer aided manufacturing (CAD/CAM) inlays.@*METHODS@#One hundred extracted human molars were prepared by criteria of buccal occlusal (BO) inlay. On the buccal, the mesial margin was prepared as 135° bevel while the distal margin was prepared as butt-joint. All-ceramic restorations were made in the Sirona CEREC AC CAD/CAM system with VitaBlocs Mark Ⅱ, Upcera UP.CAD, IPS e.max CAD, Upcera Hyramic and Lava Ultimate. The gaps between each inlay's mesial margin-abutment and distal margin-abutment were recorded under an optical microscope. Each inlay was adhered to the abutment and aged by thermal cycling for 10 000 times. Each specimen was cut into 3 slices after staining. Dye penetration was evaluated under an optical microscope for mesial and distal margins.@*RESULTS@#Mean marginal integrity rate, mean marginal gap value and mean depth of microleakage of 135° margin of Group Upcera Hyramic and Lava Ultimate were significantly better than those of Group VitaBlocs Mark Ⅱ, Upcera UP.CAD and IPS e.max CAD(P < 0.05). Mean marginal gap value, mean depth of microleakage and scale of mean depth of microleakage of 90° margin of Group Upcera Hyramic and Lava Ultimate were significantly better than those of Group Upcera UP.CAD and IPS e.max CAD (P < 0.05) while mean marginal integrity rate was not significantly different (P>0.05). Mean marginal integrity rate of 90° margin was significantly better than that of 135° margin in each group (P < 0.05) while mean depth of microleakage between different margins was not significantly different in each group (P>0.05). Mean marginal gap value of 90° margin of Group VitaBlocs Mark Ⅱ and IPS e.max CAD was significantly better than that of 135° margin (P < 0.05) while there was not significant difference in other 3 groups between 90° and 135° margin (P>0.05). Scale of mean depth of microleakage of 135° margin of Group Upcera Hyramic and Lava Ultimate was significant better than that of 90° margin (P < 0.05) while there was not significantly different in other 3 groups between 90° and 135° margin (P>0.05).@*CONCLUSION@#The mesial and distal margins of abutement of all-ceramic inlay should be prepared as butt-joint.

One year clinical evaluation of fracture and marginal integrety of milled biohpp polyetheretherketon (PEEK) versus zirconia veneered single crowns / Avaliação clínica de um ano de fratura e integredade marginal de coroas fresadas à base de biohpp polieteretercetona (PEEK) versus coroas estratificadas de zircônia unitárias (ensaio clínico controlado randomizado)

Objectives: To compare the clinical performance of milled PEEK-based single crowns to zirconia veneered single crowns through evaluation of restoration fracture, margin adaptation, and patient satisfaction. Material and Method: Twenty-four full coverage crowns were fabricated for posterior teeth. The patients were divided into two groups according to crowns' material: Group 1(control group) patients received Zr veneered crowns and Group2 (intervention group) patients received Bio HPP crowns. The preparations were standardized with supra-gingival, chamfer finish line for all teeth. The try-in and provisionalization were performed using CAD/CAM (CAM5-S1) machine with software (Exocad). The restorations were veneered according to manufactures instructions. The restoration surfaces were treated according to the manufacture instructions for each material. Self-adhesive resin cement (by BISCO) was used for both groups for crowns cementation. Fracture, margin integrity and biocompatibility (shade and function) were also evaluated during each recall visit using questionnaire to determine patient satisfaction. These measurements were repeated after two, four, six, eight, ten and twelve months respectively. Results: Fisher's Exact test was used to compare between the two groups; There was no statistically significant difference between the two groups (P-value = 1.000, Effect size = 0.478) for each time period, respectively. Conclusions: Both Zr veneered and Bio HPP crowns revealed successful clinical performance from the clinical performance aspect and patient satisfaction. No significant difference was recorded between the two materials; regarding the clinical performance and patient satisfaction. Therefore, careful checking of the surface of the veneering material one-year post-cementation is recommended (AU)

Objetivo: Comparar o desempenho clínico de coroas unitárias fresadas à base de PEEK com coroas unitárias estratificadas de zircônia por meio da avaliação da fratura da restauração, adaptação marginal e satisfação do paciente. Material e Métodos: Vinte e quatro coroas totais posteriores foram confeccionadas. Os pacientes foram divididos em dois grupos de acordo com o material das coroas: os pacientes do Grupo 1 (grupo controle) receberam coroas estratificadas de Zr e os pacientes do Grupo 2 (grupo de intervenção) receberam coroas BioHPP. Os preparos foram padronizados com linha de término supragengival e chanfro para todos os dentes. O try-in e a provisionalização foram realizados em máquina CAD / CAM (CAM5-S1) com software (Exocad). As restaurações foram estratificadas de acordo com as instruções do fabricante. As superfícies da restauração foram tratadas de acordo com as instruções do fabricante de cada material. O cimento resinoso autoadesivo (BISCO) foi utilizado para a cimentação das coroas em ambos os grupos. Fratura, integridade marginal e biocompatibilidade (tonalidade e função) também foram avaliadas durante cada consulta de retorno usando um questionário para determinar a satisfação do paciente. Essas medições foram repetidas após dois, quatro, seis, oito, dez e doze meses, respectivamente. Resultados: o teste exato de Fisher foi usado para comparação entre os dois grupos; não houve diferença estatisticamente significativa entre os dois grupos (P-valor = 1,000, tamanho do efeito = 0,478) para cada período de tempo, respectivamente. Conclusão: As coroas estratificadas de Zr e BioHPP revelaram um desempenho clínico bem-sucedido do ponto de vista do desempenho clínico e da satisfação do paciente. Nenhuma diferença significativa foi registrada entre os dois materiais; quanto ao desempenho clínico e satisfação do paciente. Portanto, recomenda-se a verificação cuidadosa da superfície do material de estratificação após um ano de cimentação.(AU)

A one-year clinical evaluation of IPS E. max press versus CERASMART endocrowns in anterior endodontically treated teeth: a randomised clinical / Avaliação clínica de um ano de IPS E. max Press versus CERASMART endocrowns em dentes anteriores tratados endodonticamente: um ensaio clínico randomizado

Objective: The purpose of this study was to evaluate and compare gross fracture, patient satisfaction and marginal adaptation of anterior endocrowns restoring endodontically treated anterior teeth fabricated from IPS e.max press and CERASMART hybrid ceramics. Material and Methods: A total of 24 patients were selected to receive an aesthetic endocrown for an upper tooth in the aesthetic zone (central incisor, lateral and canine).The 24 patients were divided into two groups (n= 12 each), where Group 1, the control group, received an IPS e.max press anterior endocrown and Group 2, theintervention group, received a CERASMART anterior endocrown. After cementation all patients were followed up at 3, 6, 9 and 12 months. During each follow-up examination, United States Public Health Servicecriteria were adopted for clinical evaluation to score margin integrity and gross fracture. Questionnaires were also used to evaluate the patients' satisfaction and potential postoperative discomfort. The X2 or Fisher's Exact test were used to compare qualitative variables in the two groups and Friedman's test was used to study the changes over time within each group. The significance level was set at P≤ 0.05. Results: With regard to gross fracture and marginal integrity, there was no statistically significant difference at any time interval between IPS e.max press and CERASMART endocrowns. All patients reported being satisfied with their restorations until the end of the follow-up period. Conclusions: CERASMART anterior endocrowns provided a promising treatment modality compared to IPS e.max press anterior endocrowns. (AU)

Objetivo: o objetivo deste estudo foi avaliar e comparar a fratura grosseira, a satisfação do paciente e a adaptação marginal de endocrowns em dentes anteriores tratados endodonticamente, fabricados a partir de IPS e.max press e cerâmicas híbridas CERASMART. Material e Métodos: Um total de 24 pacientes foi selecionado para receber endocrown em um dente superior na zona estética (incisivo central, lateral e canino). Os 24 pacientes foram divididos em dois grupos (n = 12 cada), onde o Grupo 1, o grupo controle, recebeu uma endocrown anterior IPS e.max press e o Grupo 2, o grupo de intervenção, recebeu uma endocrown anterior CERASMART. Após a cimentação, todos os pacientes foram acompanhados em 3, 6, 9 e 12 meses. Durante cada exame de acompanhamento, os critérios do Serviço de Saúde Pública dos Estados Unidos foram adotados para avaliação clínica para pontuar integridade de margem e fratura grosseira. Questionários também foram usados para avaliar a satisfação dos pacientes e potencial desconforto pós-operatório. O teste X2 ou teste de Fisher foi usado para comparar as variáveis qualitativas nos dois grupos, e o teste de Friedman foi usado para estudar as mudanças ao longo do tempo dentro de cada grupo. O nível de significância foi estabelecido em P≤ 0,05. Resultados: Com relação à fratura grosseira e integridade marginal, não houve diferença estatisticamente significativa em qualquer intervalo de tempo entre os endocrowns IPS e.max press e CERASMART. Todos os pacientes relataram estar satisfeitos com suas restaurações até o final do período de acompanhamento. Conclusão: os endocrowns anteriores CERASMART proporcionaram uma modalidade de tratamento promissora em comparação com os endocrowns anteriores IPS e.max press. (AU)

OCT- An Emerging Diagnostic Tool in Sensing Marginal Integrity of Nano Composites.

Objectives: The purpose of the present research was to demonstrate images of failure into the structure of nano composites using optical coherence tomography. Methods: Ten human third mandibular molars were taken in the study. A class V cavity was prepared and restored with nano composite universal. 20 OCT images of each tooth were obtained and a total of 200 images were evaluated after restoration. Spectral domain (SD-OCT), at 840 nm and a measured spatial resolution of 10 µm was used for the study, which is based on the Michelson interferometer set-up and is controlled by the software OCT 800 – Complex Square/LabView, that collects data and generates the image. The restored surfaces were scanned in a bucco-lingual direction and tomographic images were obtained. Later, the crown of each tooth was sectioned in a occlusogingival direction (buccolingually) and images of each section were obtained by a Stereo microscope. Images of OCT and stereo microscope were compared and evaluated. Results: Images obtained by OCT helped in identifying failures at surface and in the internal structure of composites. Significance: Images obtained from OCT helps in detecting the failures, gaps, bubbles which adversely effect the longevity of restoration.

Estudo clínico longitudinal de dentes restaurados com sistemas cerâmicos livres de metal: estudo prospectivo sobre a hipersensibilidade dental pós-operatória / Longitudinal clinical study of teeth restored with metal-free ceramic systems: prospective study about the post-operative dental hypersensitivity

Considerando a importância da hipersensibilidade dental pósoperatória no sucesso clínico das restaurações cerâmicas em curto prazo e a influência da integridade marginal e da linha de cimentação para os resultados longitudinais neste tipo de restauração, o objetivo deste estudo clínico foi avaliar a ocorrência da hipersensibilidade dental pós-operatória em dentes restaurados com cerâmicas livres de metal, com o uso de aparelho estimulador de temperatura e a verificação da integridade marginal da linha de cimentação com o Microscópio Eletrônico de Varredura (MEV). Materiais e Métodos: No primeiro capítulo, 28 laminados cerâmicos foram instalados sendo: 15 com Rely X Veneer (RV) e 13 com Variolink Veneer (VV), cimentadas de acordo com um ensaio clínico randomizado do tipo Split-mouth design. Os dentes restaurados foram submetidos ao teste de limiar de sensibilidade por sensação ao frio através do aparelho estimulador TSA II antes do procedimento restaurador (baseline) e após 5 tempos de análise [24h após a cimentação (t0), 7 dias após t0 (t1), 15 (t2), 30 (t3), 60 dias após t0 (t4)]. No segundo capítulo, 62 dentes foram restaurados sendo 32 cimentados com RV e 30 com VV seguindo o modelo do Split-mouth design. Dezenove coroas foram cimentadas com Rely X U200 [U]. A integridade marginal da restauração cerâmica e da linha de cimentação foi avaliada no MEV e a avaliação clínica baseada nos critérios modificados do USPHS (United States Public Health Service) foi realizada nos tempos [T0 (dia da cimentação), 30 (T1) e 180 dias após T0 (T2)], sendo também realizadas análises fractográficas adicionais das fraturas ocorridas. Resultados: O teste sensorial quantitativo não verificou aumento da sensibilidade dentária após a instalação das restaurações em nenhum dos grupos experimentais (p>0,05), entretanto 57,2% dos pacientes relataram hipersensibilidade dental pós-operatória em hábitos alimentares na avaliação de 30 dias. Para os dentes avaliados na segunda...

Considering the importance of post-operative dental hypersensitivity in clinical success of ceramic restorations in the short-term and the influence of the marginal integrity and the cementing line in the longitudinal results in this type of restoration, the aim of this clinical study is to evaluate the occurrence of post-operative hypersensitivity of teeth restored with metal-free ceramics, with the use of stimulating device temperature and verification of marginal integrity of cementation line with the scanning Electron Microscope (SEM). Materials and Methods: In the first chapter, 28 metal free restorations were installed, being 15 with Rely X Veneer (RV), 13 with Variolink Veneer (VV), cemented according to a Split-mouth design clinical trial model. The restored teeth were subjected to sensitivity threshold test by the cold sensation through the stimulator TSA II apparatus before the restorative procedure (baseline) and after 5 times of analysis [24h after cementation (t0 ) 7 days after t0 (t1) 15 (t2), 30 (t3), 60 days after t0 (t4)]. In the second chapter, 62 teeth were restored, being: 32 with RV, 30 with VV, according to a randomized clinical trial based in Split-mouth design. 19 crows were cemented with Rely X U200 [U]. The marginal integrity of ceramic restoration and the cementation line was evaluated in SEM and a clinical assessment based on modified criteria of the USPHS (United States Public Health Service) was performed at the times [t0 (day cementation), 30 (t1) and 180 days after t0 (t2)]. Results: Quantitative sensory testing found no increase in tooth sensitivity after installation of restorations in any of the experimental groups (p <0.05). However, 57,2% of patients reported postoperative dental hypersensitivity in eating habits on 30-day control. For teeth evaluated in the second stage of the study, 58.02% presented with horizontal marginal cement excess at T0, reduced to 14,82% in T1, problem not present in T2. One crown that...

CAD/CAM In Dental Restorations: An Overview.

In the last two decades, exciting new developments in dental materials and computer technology have led to the success of dental computer aided design/computer aided manufacturing (CAD/CAM) technology. CAD/CAM is proving to be a valuable image enhancer, production booster and profit generator. Highly sophisticated chair side and laboratory CAD/CAM systems have been introduced. This article provides an overview of various CAD/CAM systems.

The effect of the endodontic access cavity on the marginal leakage of crowns / 대한치과보존학회지

The marginal integrity of the crown can be broken during endodontic access cavity preparation due to the vibration of burs. Therefore, the purpose of this study was to evaluate the effect of endodontic access cavity preparation on the marginal leakage of full veneer gold crowns. 24 intact molars were mounted in acrylic resin blocks and prepared for crowns by a restorative dentist and crowns were cast with gold alloy. 20 Crowns were cemented with glass ionomer cement and 2 crowns were not cemented for positive control. 200 thermo-cycles from 5degrees C to 50degrees C with a travel time of 20s were completed. Then samples were randomly divided into 2 experimental groups of 9 each. Endodontic access preparation and zinc-oxide eugenol temporary fillings were done in Group 1. Teeth in Group 2 were not treated. Samples were coated with 2 layers of nail varnish and were immersed in 1% methylene blue dye for 20 hrs. Endodontic access was prepared in 2 samples, which were coated with nail varnish on all surfaces for negative control. After washing in running water, gold crowns were cut with a #330 bur. Four buccolingual sections, 2 mm apart, were cut from the central section of each tooth and were examined and scored under the microscope for dye leakage. Score 1: leakage to the cervical 1/3 of the axial wall, Score 2: leakage to the middle 1/3 of the axial wall, Score 3: leakage to the coronal 1/3 of the axial wall, Score 4: leakage to the occlusal surface. The median value for Group 1 is 4 and for Group 2 is 2. The result of this study showed that samples in Group 1 leaked more than those in Group 2. This finding was significant(P<0.001).