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1.
Dent Clin North Am ; 59(3): 593-608, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26140967

RESUMO

The clinical example presented in this article demonstrates a risk-based, diagnostically driven treatment planning approach by focusing on 4 key categories: periodontal, biomechanical, functional, dentofacial. In addition, our unique approach allowed the comprehensive clinical management of a patient with complex restorative needs. A full-mouth rehabilitation was completed sequentially without sacrificing the amount of dentistry necessary to restore health, comfort, function, and esthetics. The result exceeded the patient's expectation and was made financially possible by extending treatment over numerous years.


Assuntos
Assistência Odontológica Integral , Reabilitação Bucal/métodos , Planejamento de Assistência ao Paciente , Bruxismo/terapia , Corrosão , Coroas , Porcelana Dentária/química , Restauração Dentária Permanente , Facetas Dentárias , Estética Dentária , Seguimentos , Humanos , Masculino , Ligas Metalo-Cerâmicas/química , Pessoa de Meia-Idade , Medição de Risco , Sorriso , Atrito Dentário/terapia , Descoloração de Dente/terapia , Preparo Prostodôntico do Dente/métodos
2.
Int J Comput Dent ; 18(1): 65-84, 2015.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-25911830

RESUMO

In esthetic rehabilitation, it is a challenge to meet the needs of patients with growing expectations. Creating predictable results is the key to success. This can be accomplished by performing a comprehensive esthetic diagnosis, elaborating treatment proposals that satisfy today's esthetic standards, and using modern computer-assisted methods. The diagnostic wax-up and mock-up are effective tools that allow patients to visualize treatment proposals without invasive procedures. Once the patient has approved the proposals, they provide the basis for the fabrication of the final restoration. The use of modern ceramic materials makes it possible to achieve a good esthetic outcome, even in restorations with extremely thin layer thicknesses. Esthetic cementation is the final step of restorative treatment.


Assuntos
Planejamento de Prótese Dentária , Estética Dentária , Planejamento de Assistência ao Paciente , Adulto , Cimentação/métodos , Cerâmica/química , Assistência Odontológica Integral , Desenho Assistido por Computador , Tomografia Computadorizada de Feixe Cônico/métodos , Cimentos Dentários/química , Materiais Dentários/química , Porcelana Dentária/química , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Incisivo/anormalidades , Modelos Dentários , Fotografia Dentária/métodos , Terapia Assistida por Computador , Preparo Prostodôntico do Dente/métodos , Resultado do Tratamento , Interface Usuário-Computador
3.
Compend Contin Educ Dent ; 36(2): 135-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25822640

RESUMO

This article reviews the case of a male patient with esthetic concerns about a large diastema between teeth Nos. 8 and 9. Through functional analysis, the clinician determined that the patient had a mild temporomandibular disorder, as well as a constriction in his anterior envelope of function. These issues will affect the prognosis of treatment if only orthodontics is used to close the diastema. The clinician determined that implementing a systematic treatment planning approach was critical in achieving a successful outcome, which was accomplished with a combination of orthodontics, occlusal deprogramming, and complex prosthodontics restorations.


Assuntos
Restauração Dentária Permanente , Diastema/terapia , Estética Dentária , Ortodontia Corretiva , Preparo Prostodôntico do Dente/métodos , Adulto , Cárie Dentária/terapia , Diagnóstico Diferencial , Humanos , Masculino , Periodontite/diagnóstico , Periodontite/terapia , Clareamento Dental , Descoloração de Dente/terapia
4.
J Prosthet Dent ; 114(1): 86-91, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25794907

RESUMO

STATEMENT OF PROBLEM: How the location of a ferrule affects the fracture resistance of endodontically treated mandibular premolars is unclear. PURPOSE: The purpose of this in vitro study was to compare the effect of ferrule location on the fracture resistance of endodontically treated mandibular premolars. MATERIAL AND METHODS: Seventy-two extracted human mandibular premolars were selected and divided into 6 test groups (n = 12) according to ferrule location: control group, GHT; endodontically treated teeth without endodontic posts and crowns, GCF; teeth with a 2 mm circumferential ferrule, GBF; teeth with a 2 mm buccal ferrule; GLF, teeth with a 2 mm lingual ferrule; GBLF, teeth with a 2 mm buccal and lingual ferrule; and teeth without ferrule, GWF. After glass fiber posts were cemented with a self-adhesive resin cement and foundation restorations were placed, NiCr crowns were luted to each prepared tooth. All specimens were quasistatically loaded at 30 degrees in a universal testing machine until fractured. Data were then analyzed with 1-way ANOVA, followed by multiple comparisons using the Tukey honestly significant difference test (α=.05). RESULTS: Mean ± SD failure loads for groups ranged from 791.1 ± 177.5 N to 1086.1 ± 181.1 N. One-way ANOVA revealed a statistically significant difference between the groups (P ≤ .05). However, no statistically significant differences were observed among groups (P > .05), except between GHT (control group) and groups GBLF and GWF (P = .025, P = .022). CONCLUSIONS: Within the limitations of this study, the location of the ferrule had no significant effect on the fracture resistance of endodontically treated mandibular premolars.


Assuntos
Dente Pré-Molar/fisiopatologia , Coroas , Técnica para Retentor Intrarradicular/instrumentação , Fraturas dos Dentes/fisiopatologia , Preparo Prostodôntico do Dente/instrumentação , Dente não Vital/fisiopatologia , Óxido de Alumínio/química , Cimentação/métodos , Ligas de Cromo/química , Corrosão Dentária/métodos , Materiais Dentários/química , Planejamento de Prótese Dentária , Análise do Estresse Dentário/instrumentação , Vidro/química , Cimentos de Ionômeros de Vidro/química , Humanos , Mandíbula , Cimentos de Resina/química , Preparo de Canal Radicular/métodos , Estresse Mecânico , Propriedades de Superfície , Raiz Dentária/lesões
5.
Dent Update ; 42(10): 933-6, 938, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26855999

RESUMO

This article details the clinical techniques for conventional preformed metal crown placement. It aims to increase the readers' awareness of the clinical advantages of preformed metal crowns and the indications for their use. The second part will discuss the Hall Technique. CPD/Clinical Relevance: This two-part article aims to guide the reader through the conventional and alternative techniques available for placement of a preformed metal crown whilst providing an update of the evidence for each.


Assuntos
Coroas , Ligas Dentárias/química , Restauração Dentária Permanente/métodos , Dente Decíduo/patologia , Anestesia Dentária , Anestesia Local , Cimentação/métodos , Criança , Ligas de Cromo/química , Cárie Dentária/terapia , Adaptação Marginal Dentária , Estética Dentária , Humanos , Satisfação do Paciente , Padrões de Prática Odontológica , Análise de Sobrevida , Preparo Prostodôntico do Dente/métodos , Reino Unido
6.
Rev. Fundac. Juan Jose Carraro ; 20(40): 7-15, 2015. tab
Artigo em Espanhol | LILACS | ID: lil-764266

RESUMO

Las preparaciones dentales para prótesis fija, involucran al tejido duro, además la proximidad que existe con la encía hace necesario la comprensión de su estructura y la función del aparato de protección, para que las restauracionesno invadan el ancho biológico constituido por el epitelio de unión y las fibras gingivales; basándonos en los estudios de Gargiulo en 1961, donde la inserción del tejido conjuntivo mide 1.07 mm y la adherencia epitelial 0.97 mm en promedio, sumados al espacio del surco gingival. El biotipo periodontal es de vital importancia para la elección de la altura de terminación del hombro de la preparación, donde el mismo deberá establecerse, previo sondaje óseo a no menos de 2.5 mm de la cresta según Kois (2008). La utilización de materiales y técnicas para la toma de impresiones definitivas deben ser amigables con los tejidos blandos a fin de no producir alteraciones y que las restauraciones sean predecibles, tanto funcional como estéticamente en el transcurso del tiempo


Dental preparations fixed prosthesis, involving the hard tissue, there is also proximity to the gum is necessary to understand the structure and function of the protection device, to restorations without invading the biologic width consisting of the epithelium junction and the gingival fibers; based on Gargiulo studies in 1961, where the insertion of the connective tissue and epithelial measured 1.07 mm 0.97 mm in average adhesion, coupled with sulcular space. The periodontal biotype is of vital importance for the choice of the termination of the shoulder height of the preparation, where it must be established prior tobone sounding no less than 2.5mm crest according Kois (2008). The use of materials and techniques for making final impressions should be friendly soft so as not to alter tissues and restorations predictable, both functionally and aesthetically over time.


Assuntos
Humanos , Planejamento de Prótese Dentária , Prótese Parcial Fixa , Preparo Prostodôntico do Dente/métodos , Biotipologia , Coroas , Técnica de Moldagem Odontológica , Gengiva/anatomia & histologia , Inserção Epitelial/anatomia & histologia , Materiais Dentários/classificação , Periodonto/anatomia & histologia
7.
Eur J Oral Sci ; 122(4): 310-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24910293

RESUMO

The purpose of this in-vitro study was to evaluate the influence of the framework design on the durability of inlay-retained cantilever fixed dental prostheses (IR-FDPs), made from zirconia ceramic, after artificial ageing. Forty-eight caries-free human premolars were prepared as abutments for all-ceramic cantilevered IR-FDPs using six framework designs: occlusal-distal (OD) inlay, OD inlay with an oral retainer wing, OD inlay with two retainer wings, mesial-occlusal-distal (MOD) inlay, MOD inlay with an oral retainer ring, and veneer partial coping with a distal box (VB). Zirconia IR-FDPs were fabricated via computer-aided design/computer-aided manufacturing (CAD/CAM) technology. The bonding surfaces were air-abraded (50 µm alumina/0.1 MPa), and the frameworks were bonded with adhesive resin cement. Specimens were stored for 150 d in a 37°C water bath during which they were thermocycled between 5 and 55°C for 37,500 cycles; thereafter, they were exposed to 600,000 cycles of dynamic loading with a 5-kg load in a chewing simulator. All surviving specimens were loaded onto the pontic and tested until failure using a universal testing machine. The mean failure load of the groups ranged from 260.8 to 746.7 N. Statistical analysis showed that both MOD groups exhibited significantly higher failure loads compared with the other groups (i.e. the three OD groups and the VB group) and that there was no significant difference in the failure load among the OD groups and the VB group. In conclusion, zirconia IR-FDPs with a modified design exhibited promising failure modes.


Assuntos
Materiais Dentários/química , Planejamento de Dentadura , Encaixe de Precisão de Dentadura , Retenção de Dentadura/instrumentação , Prótese Parcial Fixa , Restaurações Intracoronárias , Zircônio/química , Óxido de Alumínio/química , Dente Pré-Molar , Força de Mordida , Desenho Assistido por Computador , Dente Suporte , Colagem Dentária , Corrosão Dentária/métodos , Análise do Estresse Dentário/instrumentação , Facetas Dentárias , Humanos , Teste de Materiais , Cimentos de Resina/química , Estresse Mecânico , Temperatura , Fatores de Tempo , Preparo Prostodôntico do Dente/métodos , Água/química
8.
J Prosthet Dent ; 112(4): 871-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24750896

RESUMO

STATEMENT OF PROBLEM: Information about the effect of occlusal preparation designs on the stress distribution in different ceramic crowns and the prepared tooth is limited. PURPOSE: The purpose of this study was to investigate the effects of anatomic and nonanatomic occlusal preparation designs on the stress distribution in ceramic crowns, teeth, and bone. MATERIAL AND METHODS: Finite element analysis was performed on models of a mandibular second premolar. A load of 400 N was applied to the models to test ceramic materials (In-Ceram, Empress Esthetic) and occlusal preparation (anatomic, nonanatomic) designs. RESULTS: The lowest stress value occurred in the core material in the Empress Esthetic model prepared with the nonanatomic occlusal preparation design. In all groups, higher stress values were found to be concentrated in the lingual half of the dentin. Lower stress values were located near the apex of the pulp tissue and bony tissue that surround the root apex. CONCLUSIONS: Differences in preparation designs did not result in differences in the distribution or amount of stress in pulp, dentin, or bone. The use of different ceramic materials resulted in no differences in the amount or distribution of stress in pulp and bone. The use of a crown with a high elastic modulus led to increases in stress values in the restoration and the dentin margin, and decreases in stress values in the occlusal surface of the dentin. The nonanatomic design can be recommended as a favorable preparation design for Empress Esthetic ceramic.


Assuntos
Cerâmica/química , Coroas , Materiais Dentários/química , Análise de Elementos Finitos , Preparo Prostodôntico do Dente/métodos , Óxido de Alumínio/química , Silicatos de Alumínio/química , Processo Alveolar/anatomia & histologia , Dente Pré-Molar/anatomia & histologia , Porcelana Dentária/química , Polpa Dentária/anatomia & histologia , Dentina/anatomia & histologia , Módulo de Elasticidade , Humanos , Mandíbula , Estresse Mecânico , Ápice Dentário/anatomia & histologia
9.
J Prosthet Dent ; 111(5): 395-403, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24529652

RESUMO

STATEMENT OF PROBLEM: Information about the influence of zirconia crown surface treatment and cement type on the retention of zirconia crowns is limited. It is unclear whether zirconia crowns require surface treatment to enhance their retention. PURPOSE: The purpose of this in vitro study was to evaluate the effect of surface treatment on the retention of zirconia crowns cemented with 3 different adhesive resin cements after artificial aging. MATERIAL AND METHODS: Ninety extracted human molars were prepared for ceramic crowns (approximately 20-degree taper, approximately 4-mm axial length) and were divided into 3 groups (n=30). Computer-aided design and computer-aided manufacturing zirconia copings were fabricated. Three surface treatments were applied to the intaglio surface of the copings. The control group received no treatment, the second group was airborne-particle abraded with 50 µm Al2O3, and the third group was treated with 30 µm silica-modified Al2O3, The copings were luted with a self-etch (RelyX Unicem 2), a total-etch (Duo-Link), or a self-etch primer (Panavia F 2.0) adhesive cement. They were stored for 24 hours at 37°C before being artificially aged with 5000 (5°C-55°C) thermal cycles and 100,000 cycles of 70 N dynamic loading. Retention was measured on a universal testing machine under tension, with a crosshead speed of 0.5 mm/min. Statistical analysis was performed with 1-way and 2-way ANOVA. RESULTS: Mean retention values ranged from 0.72 to 3.7 MPa. Surface treatment increased crown retention, but the difference was not statistically significant (P>.05), except for the Duo-Link cement group (P<.05). Analysis of the adhesives revealed that the Duo-Link cement resulted in significantly lower crown retention (P<.05) than the other 2 cements. CONCLUSION: For zirconia crowns, retention seems to be dependent on cement type rather than surface treatment.


Assuntos
Coroas , Materiais Dentários/química , Retenção em Prótese Dentária , Cimentos de Resina/química , Ítrio/química , Zircônio/química , Óxido de Alumínio/química , Desenho Assistido por Computador , Colagem Dentária , Corrosão Dentária/métodos , Planejamento de Prótese Dentária , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Dióxido de Silício/química , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo , Preparo Prostodôntico do Dente/métodos
10.
Dent Mater J ; 32(4): 537-43, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23903633

RESUMO

To evaluate failure loads of teeth restored by use of alumina-coping, and to assess the effects of different amounts of residual tooth structure and different cements, standardized artificial alumina copings were fabricated on seventy-two molars. 24 of the copings were cemented by use of an adhesive resin cement (P-group), n=24 by use of glass-ionomer cement (K-group), and n=24 by use of a self-adhesive modified composite resin-cement (R-group). After artificial ageing (10,000 thermal-cycles between 6.5 and 60°C; 1,200,000 chewing cycles with Fmax=64 N), the specimens were loaded until failure (cross-head-speed: 0.5 mm/min). In the K-group 83% of the specimens failed during chewing simulation. Statistical analysis included chi-squared-test, unpaired-to-sample-t-test, and ANOVA. For severely damaged teeth, loads to failure in the P-group (384 N) were significantly (p=0.03) higher than in the R-group (295 N). For severely damaged teeth, use of composite resin cement resulted in higher loads to failure than use of other cements.


Assuntos
Óxido de Alumínio/química , Cimentação/métodos , Coroas , Materiais Dentários/química , Falha de Restauração Dentária , Dente Molar/fisiopatologia , Preparo Prostodôntico do Dente/métodos , Condicionamento Ácido do Dente/métodos , Fenômenos Biomecânicos , Força de Mordida , Resinas Compostas/química , Corrosão Dentária/métodos , Análise do Estresse Dentário/instrumentação , Cimentos de Ionômeros de Vidro/química , Humanos , Óxido de Magnésio/química , Metacrilatos/química , Cimento de Policarboxilato/química , Técnica para Retentor Intrarradicular , Cimentos de Resina/química , Estresse Mecânico , Temperatura , Tionas/química , Fatores de Tempo , Óxido de Zinco/química
11.
Dent Mater ; 29(8): 815-23, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23746750

RESUMO

OBJECTIVES: Fracture strength measured in vitro indicates that most all-ceramic crowns should be able to withstand mastication forces. Nevertheless, fractures are one of the major clinical problems with all-ceramic restorations. Furthermore, the fracture mode of all-ceramic crowns observed in clinical use differs from that found in conventional fracture strength tests. The aim of the present study was to develop and investigate a method that simulates clinical fracture behavior in vitro. METHODS: 30 crowns with alumina cores were made to fit a cylindrical model with a molar-like preparation design. These crowns were randomly allocated to 3 tests groups (n=10). The crowns in group 1 were cemented to abutment models of epoxy and subsequently fractured by occlusal loading without contact damage. The crowns in group 2 were fractured by cementation with expanding cement. The crowns in group 3 were cemented on an abutment model of epoxy split almost in two and fractured by increasing the diameter of the model in the bucco-lingual direction. The fractured crowns were analyzed by fractographic methods and compared to a reference group of 10 crowns fractured in clinical use. RESULTS: The fracture modes of all the in vitro crowns were similar to clinical fracture modes. The fracture modes in group 1 were most closely matched to the clinical fractures. These crowns also fractured at clinically relevant loads. CONCLUSION: Laboratory tests that induce a distortion of the abutment model during occlusal loading without occlusal contact damage can simulate clinical fractures of all-ceramic crowns.


Assuntos
Cerâmica/química , Coroas , Materiais Dentários/química , Óxido de Alumínio/química , Força de Mordida , Cimentação/métodos , Cobre/química , Adaptação Marginal Dentária , Porcelana Dentária/química , Planejamento de Prótese Dentária , Falha de Restauração Dentária , Facetas Dentárias , Elastômeros/química , Resinas Epóxi/química , Etilenos/química , Humanos , Teste de Materiais/instrumentação , Teste de Materiais/métodos , Ligas Metalo-Cerâmicas/química , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo , Titânio/química , Preparo Prostodôntico do Dente/métodos , Água/química , Zinco/química , Cimento de Fosfato de Zinco/química
12.
J Prosthodont ; 21(8): 614-21, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22823334

RESUMO

PURPOSE: This in vitro study aimed to determine the ability of three resin cements to retain zirconia copings under two clinically simulated conditions. MATERIALS AND METHODS: Extracted human molars (72) were collected, cleaned, and divided into two groups. All teeth were prepared with a 15° total convergence angle for group 1 and a 30° total convergence angle for group 2, a flat occlusal surface, and approximately 4-mm axial length. Each group was divided by surface area into three subgroups (n = 12). All zirconia copings were abraded with 50-µm Al(2)O(3), then cemented using Panavia F 2.0 (PAN-1) (PAN-2) Rely X Unicem (RXU-1) (RXU-2), and Clearfil SA (CSA-1) (CSA-2). After cementation, the copings were thermocycled for 5000 cycles between 5°C and 55°C with a 15-second dwell time. Then the copings were subjected to dislodgment force in a universal testing machine at 0.5 mm/min. The force of removal was recorded, and the dislodgement stress was calculated. A Kruskal-Wallis test (nonparametric ANOVA) was used to analyze the data (α= 0.05), and the nature of failure was also recorded. RESULTS: The mean (SD) coping removal stresses (MPa) were as follows: PAN-1: 6.0 (1.3), CSA-1: 4.8 (1.4), RXU-1: 5.5 (2.3), PAN-2: 2.8 (1.1), CSA-2: 3.0 (1.25), and RXU-2: 2.6 (1.2). The Kruskal-Wallis test was significant. Mann-Whitney pairwise comparisons of the subgroups were significant (p < 0.05) for the comparisons between subgroups of group 1 and group 2. Mode of failure was mixed, with cement remaining principally on the tooth for PAN. For CSA and RXU, mode of failure was mixed with cement remaining principally on the zirconia copings. CONCLUSIONS: Retention values of zirconia copings with three different resin cements were not significantly different. Retention of zirconia copings cemented on the teeth with adequate resistance and retention form was higher than that cemented on teeth lacking these forms. The cement remained mostly on the tooth with the adhesive resin cement with a dentin bonding system. The cement remained mostly on the coping with the self-adhesive resin cement.


Assuntos
Coroas , Dente Suporte , Materiais Dentários/química , Planejamento de Prótese Dentária , Retenção em Prótese Dentária , Cimentos de Resina/química , Zircônio/química , Óxido de Alumínio/química , Cimentação/métodos , Desenho Assistido por Computador , Corrosão Dentária/métodos , Falha de Restauração Dentária , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo , Preparo Prostodôntico do Dente/métodos
13.
Am J Dent ; 25(2): 67-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22779278

RESUMO

PURPOSE: To analyze the effect of ceramic manufacturing technique and luting cement selection on the marginal adaptation of zirconium oxide-based all-ceramic crowns. METHODS: An extracted mandibular first premolar was prepared for a complete coverage restoration and subsequently duplicated 40 times in a liquid crystal polymer (LCP). All-ceramic crowns (n = 10) were fabricated on LCP models using the following systems: glass-infiltrated zirconia-toughened alumina (In-Ceram Zirconia) and yttrium cation-doped tetragonal zirconia polycrystals (In-Ceram YZ, Cercon, and Procera Zirconia). The restorations (n = 5) were cemented on their respective dies with glass-ionomer cement (Ketac Cem Aplicap) and resin cement (Panavia 21). The absolute marginal discrepancy of the crowns was measured before and after cementation by scanning electronic microscopy at 160 points along the circumferential margin. The data were analyzed using one-way ANOVA for repeated measures and for independent samples, Scheffé's multiple range post hoc test, and Student's t-test (alpha = 0.05). RESULTS: There were statistical differences in the mean marginal openings among the four all-ceramic systems before and after luting (P < 0.0001). The Procera restorations had the lowest pre- and post-cementation values (P < 0.0001). A significant increase in the marginal gap size caused by luting media occurred in all tested groups (P < 0.0001). Resin cement resulted in larger marginal discrepancies than glass-ionomer cement (P < 0.0001).


Assuntos
Desenho Assistido por Computador , Coroas , Cimentos Dentários/química , Adaptação Marginal Dentária , Porcelana Dentária/química , Planejamento de Prótese Dentária , Zircônio/química , Óxido de Alumínio/química , Dente Pré-Molar , Cimentação/métodos , Cimentos de Ionômeros de Vidro/química , Humanos , Óxido de Magnésio/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Modelos Dentários , Fosfatos/química , Cimento de Policarboxilato/química , Polímeros/química , Cimentos de Resina/química , Propriedades de Superfície , Preparo Prostodôntico do Dente/métodos , Ítrio/química , Óxido de Zinco/química
14.
J Contemp Dent Pract ; 13(2): 210-5, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22665750

RESUMO

PURPOSE: The purpose of this study was to investigate the fracture loads and mode of failure of all-ceramic crowns fabricated using Top-Ceram and compare it with all-ceramic crowns fabricated from well-established systems: IPS-Empress II, In-Ceram. MATERIALS AND METHODS: Thirty all-ceramic crowns were fabricated; 10 IPS-Empress II, 10 In-Ceram alumina and 10 Top-Ceram. Instron testing machine was used to measure the loads required to introduce fracture of each crown. RESULTS: Mean fracture load for In-Ceram alumina [941.8 (± 221.66) N] was significantly (p > 0.05) higher than those of Top-Ceram and IPS-Empress II. There was no statistically significant difference between Top-Ceram and IPS-Empress II mean fracture loads; 696.20 (+222.20) and 534 (+110.84) N respectively. Core fracture pattern was highest seen in Top- Ceram specimens.


Assuntos
Coroas , Porcelana Dentária , Falha de Restauração Dentária , Análise do Estresse Dentário , Óxido de Alumínio , Cimentação , Força Compressiva , Planejamento de Prótese Dentária , Humanos , Teste de Materiais , Preparo Prostodôntico do Dente
15.
Quintessence Int ; 43(6): e73-81, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22532962

RESUMO

OBJECTIVE: To evaluate the influence of different conditioning methods of prepared teeth on the retention of cast metal copings bonded with two self-adhesive resin cements. METHOD AND MATERIALS: Mandibular first molars (n = 80) were prepared to receive metal copings. Sixteen molars were stored in water without interim copings as a control group (CG), while 64 molars were covered with interim copings. Eighty cast copings were laboratory fabricated from Ni-Cr alloy. Interim copings were removed, and 64 molars were cleaned and divided into four groups (n = 16) according to pretreatment methods of prepared molars: no pretreatment (T-NT) and conditioning with self-etching adhesive (T-SE), polyacrylic acid (T-PA), or ethylenediaminetetraacetic acid (EDTA) (T-ED). Each group was further subdivided into two subgroups (n = 8) according to luting cements. RelyX Unicem and seT self-adhesive resin cements were used for cementation of copings. Specimens were stored in water at 37°C for 6 months and then cyclically loaded and thermal cycled. Retentive stress in N was recorded for each specimen. Statistical analyses were conducted with two- and one-way ANOVA and Tukey HSD test. RESULTS: Retentive stress ranged from 526.7 to 692.9 N for RelyX Unicem and 339.8 to 492.3 N for seT. There were no statistically significant differences between the mean retentive stress of the CG, T-SE, and T-PA groups (P > .05). The mean retentive stress of group CG was significantly higher than mean retentive stress of groups T-NT and T-ED (P < .05). The mean retentive stress of the control and test groups bonded with RelyX Unicem was significantly higher than the mean retentive stress of the same groups bonded with seT. CONCLUSION: Conditioning of prepared teeth using polyacrylic acid or self-etching adhesive significantly increased the retentive stress of cast metal copings.


Assuntos
Coroas , Dente Suporte , Colagem Dentária/métodos , Retenção em Prótese Dentária , Cimentos de Resina/química , Preparo Prostodôntico do Dente/métodos , Condicionamento Ácido do Dente/métodos , Resinas Acrílicas/química , Cimentação/métodos , Ligas de Cromo/química , Resinas Compostas/química , Materiais Dentários/química , Restauração Dentária Temporária/métodos , Ácido Edético/química , Humanos , Teste de Materiais , Metacrilatos/química , Dente Molar/patologia , Poliuretanos/química , Estresse Mecânico , Temperatura , Fatores de Tempo , Água/química
16.
Int J Prosthodont ; 25(2): 170-2, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22371840

RESUMO

This study evaluated the influence of two preparation types on the marginal fit of computer-aided design/computer-assisted manufacture (CAD/CAM) alumina copings. Two subgroups of four alumina copings each were fabricated using alumina master dies with either a chamfer or 90-degree shoulder preparation. Copings were scanned with an x-ray microtomographic scanner, and marginal fit was evaluated. The preparation types presented no statistically significant differences regarding marginal gap (P = .410) and absolute marginal discrepancy (P = .229). No correlation was found between marginal fit of CAD/CAM alumina copings and preparation type. Marginal fit could be considered within the limits of clinical acceptance.


Assuntos
Óxido de Alumínio/química , Desenho Assistido por Computador , Coroas , Dente Suporte , Adaptação Marginal Dentária , Materiais Dentários/química , Preparo Prostodôntico do Dente/métodos , Planejamento de Prótese Dentária , Humanos , Projetos Piloto , Propriedades de Superfície , Microtomografia por Raio-X
17.
J. appl. oral sci ; 19(4): 370-377, July-Aug. 2011. tab
Artigo em Inglês | LILACS | ID: lil-599761

RESUMO

OBJECTIVES: To investigate if general dental practitioners (GDPs) in private practice in Jordan follow universal guidelines for preparation of anterior teeth for resin bonded all-ceramic crowns (RBCs). MATERIAL AND METHODS: A sample (n=100) of laboratory models containing 208 tooth preparations for IPS Empress and In Ceram, featuring work from different GDPs, was obtained from 8 commercial dental laboratories. Aspects of preparations were quantified and compared with accepted criteria defined following a review of the literature and recommendations of the manufactures' guidelines. RESULTS: Subgingival margins on the buccal aspect were noticed in 36 percent of the preparations, 54 percent demonstrated overpreparation with a tendency to overprepare the teeth on the mesiodistal plane more than buccolingual plane. Twenty percent of samples presented a shoulder finish line while a chamfer margin design was noticed in 39 percent. Twenty-nine percent and 12 percent of samples had either a feathered or no clear margin design respectively. Incisal underpreparation was observed in 18 percent of dies of each type. Only 17 percent of all preparations were found to follow the recommended anatomical labial preparations while 29 percent of the RBC preparations were found to have the recommended axial convergence angle. In total, 43 percent of preparations were found to have the recommended depth of the finish line. CONCLUSIONS: It was found that relevant guidelines for RBC preparations were not being fully adhered to in private practice in Jordan.


Assuntos
Humanos , Coroas , Cerâmica/uso terapêutico , Colagem Dentária/métodos , Padrões de Prática Odontológica/normas , Preparo Prostodôntico do Dente/normas , Óxido de Alumínio , Porcelana Dentária , Fidelidade a Diretrizes , Jordânia , Laboratórios Odontológicos , Prática Privada/normas , Preparo Prostodôntico do Dente/métodos
18.
J Appl Oral Sci ; 19(4): 370-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21710098

RESUMO

OBJECTIVES: To investigate if general dental practitioners (GDPs) in private practice in Jordan follow universal guidelines for preparation of anterior teeth for resin bonded all-ceramic crowns (RBCs). MATERIAL AND METHODS: A sample (n=100) of laboratory models containing 208 tooth preparations for IPS Empress and In Ceram, featuring work from different GDPs, was obtained from 8 commercial dental laboratories. Aspects of preparations were quantified and compared with accepted criteria defined following a review of the literature and recommendations of the manufactures' guidelines. RESULTS: Subgingival margins on the buccal aspect were noticed in 36% of the preparations, 54% demonstrated overpreparation with a tendency to overprepare the teeth on the mesiodistal plane more than buccolingual plane. Twenty percent of samples presented a shoulder finish line while a chamfer margin design was noticed in 39%. Twenty-nine percent and 12% of samples had either a feathered or no clear margin design respectively. Incisal underpreparation was observed in 18% of dies of each type. Only 17% of all preparations were found to follow the recommended anatomical labial preparations while 29% of the RBC preparations were found to have the recommended axial convergence angle. In total, 43% of preparations were found to have the recommended depth of the finish line. CONCLUSIONS: It was found that relevant guidelines for RBC preparations were not being fully adhered to in private practice in Jordan.


Assuntos
Cerâmica/uso terapêutico , Coroas , Colagem Dentária/métodos , Padrões de Prática Odontológica/normas , Preparo Prostodôntico do Dente/normas , Óxido de Alumínio , Porcelana Dentária , Fidelidade a Diretrizes , Humanos , Jordânia , Laboratórios Odontológicos , Prática Privada/normas , Preparo Prostodôntico do Dente/métodos
19.
Eur J Esthet Dent ; 6(1): 76-86, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21403928

RESUMO

UNLABELLED: The most common esthetic challenge associated with endodontics is the discoloration of natural tooth structure. Also in fixed prosthesis, discolorations represent an esthetic limit, particularly in the case of all-ceramic restorations. In fact, the final esthetic result can be compromised by the grey radiated through the coping and soft tissue. PURPOSE: The aim of the study was to evaluate the masking ability of Procera alumina restorations. MATERIALS AND METHODS: Clinical evaluation was investigated by using tests of discolored teeth. Each abutment, classified with Natural Die Material (Ivoclar Vivadent), were manufactured three alumina copings with thickness of 0.4, 0.6, and 0.8 mm, respectively. Masking ability for each coping was evaluated in relation to the degree of discoloration. On the basis of the results obtained, seventeen discolored teeth, treated with Procera alumina restorations, were evaluated. Color match, porcelain surface, marginal discoloration, and marginal integrity were clinically examined following modified CDA/Ryge criteria. CONCLUSION: The Procera AllCeram alumina system seems to be a reliable and excellent technology for the prosthetic treatment of moderate and serious discolored anterior teeth with an exceptionally natural look.


Assuntos
Óxido de Alumínio/química , Coroas , Porcelana Dentária/química , Planejamento de Prótese Dentária , Estética Dentária , Técnica para Retentor Intrarradicular , Descoloração de Dente/reabilitação , Cimentação/métodos , Cor , Desenho Assistido por Computador , Dente Canino/patologia , Dente Suporte , Cimentos Dentários/química , Adaptação Marginal Dentária , Prótese Parcial Fixa , Seguimentos , Humanos , Incisivo/patologia , Propriedades de Superfície , Preparo Prostodôntico do Dente/métodos , Resultado do Tratamento
20.
J Prosthet Dent ; 104(5): 306-17, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20970537

RESUMO

STATEMENT OF PROBLEM: Unresolved controversy exists concerning the remaining coronal tooth structure of anterior endodontically treated teeth and the best treatment option for restoring them. PURPOSE: The purpose of this study was to evaluate the effect of post, core, crown type, and ferrule presence on the deformation, fracture resistance, and fracture mode of endodontically treated bovine incisors. MATERIAL AND METHODS: One hundred and eighty bovine incisors were selected and divided into 12 treatment groups (n=15). The treatment variations were: with or without ferrule, restored with cast post and core, glass fiber post with composite resin core, or glass fiber post with fiber-reinforced core, and metal- or alumina-reinforced ceramic crown (n=15). The restored incisors were loaded at a 135-degree angle, and the deformation was measured using strain gauges placed on the buccal and proximal root surfaces. Specimens were subsequently loaded to the point of fracture. Strain and fracture resistance results were analyzed by 3-way ANOVA and Tukey HSD tests (α=.05). RESULTS: Ferrule presence did not significantly influence the buccal strain and fracture resistance for the ceramic crown groups, irrespective of core and crown type. Ferrule presence resulted in lower strains and higher fracture resistance in the metal crown groups, irrespective of core. The cast post and core showed lower strain values than groups with glass fiber posts when restored with metal crowns. CONCLUSIONS: Core type did not affect the deformation and fracture resistance of endodontically treated incisors restored with alumina-reinforced ceramic crowns. The presence of a ferrule improved the mechanical behavior of teeth restored with metal crowns, irrespective of core type.


Assuntos
Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Técnica para Retentor Intrarradicular , Preparo Prostodôntico do Dente/métodos , Dente não Vital/fisiopatologia , Óxido de Alumínio , Animais , Fenômenos Biomecânicos , Bovinos , Resinas Compostas , Coroas , Ligas Dentárias , Porcelana Dentária , Vidro , Incisivo , Fraturas dos Dentes/prevenção & controle
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