Porcelain Fused Research Articles

Fracture of Porcelain Fused to Yttria-Tetragonal Zirconia Polycrystals Dental Crowns from Dual-motion Cyclic Loading in Aqueous Condition

Porcelain fused to Y-TZP dental crowns are widely used in dental restorations. The fracture damage from concentrated loading especially under dual-motion cyclic loading-simulating chewing remains doubtful. Flat occlusal surface porcelain/Y-TZP ceramic crowns were fabricated following general dental practice and were supported with dentine-like composite to simulate actual dental restorations. Specimens were subjected to eccentric forces in a Willytic chewing simulator with loads of 5, 7 and 8 Kg delivered by means of steel stylus of 4mm diameter in wet condition. The damage evolution was observed at stepwise increase in cycles of 100,000 cycles each. Force measurements were taken using a 3D force sensor during dynamic loading of simultaneous axial-lateral movements. Localized surface damage which was observed at early stages was halted later after 500,000 cycles with distinctive crack patterns. Radial cracks were observed in three locations; the first location was at the porcelain inner layer under the indentation area. The second location was at the marginal extremists similar to lunar cracks observed when using soft intenders. The third location was the mesiobuccal area between the occlusal and axial sides of the crown. This latter finding may explain the chipping damage of the dental crowns. More interestingly at mesiobuccally area between the occlusal and the axial side of the crown which explain the chipping damage of dental crowns, it was believed that extension of radial cracks from indentation area are the major cause of such failure.

An Esthetic Challenge: Case Report Utilizing a Combination of Monolithic Ceramic Veneers and Porcelain Fused to Metal Crown

Copyright: © 2015 Mandiga S, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. *Corresponding author: Denise Estafan, Associate Professor and Director, Esthetic Dentistry, Department of General Dentistry, Division of Reconstructive and Comprehensive Care, New York University College of Dentistry, USA, E-mail: de1@nyu.edu

Bonding Strength of Non-precious Metal Containing no Beryllium Used as Porcelain Fused to Metal Depending on the Temperature of Degassing

치과보철물에 사용되는 도재전장 주조관 중에서 베릴륨이 미 첨가된 Ni-Cr계 비귀금속의 degassing 온도를 다르게 조절하여 금속의 산화막 형성과 metal-ceramic 결합력을 분석하였다. 이를 위해 금속과 세라믹간의 결합강도 측정하기 위해 만능시험기를 이용하여 3점 굴곡 시험을 시행하고, 결합강도 측정 후 합금-도재간의 계면을 관찰하였다. 베릴륨이 포함되지 않은 비 귀금속 합금과 도재간의 결합강도를 측정한 결과는 No-de gassing(32.92±3.55 ㎫), 960℃-degassing(35.66±1.69 ㎫), 980℃-degassing(32.82±3.28 ㎫) 값을 보였지만 유의성은 없었다. Degassing 온도에 따라 산화막 두께는 No degassing(20-25 ㎛), 960℃(5-7 ㎛), 980℃ (10-15 ㎛)로 나타났다. 비귀금속 합금과 세라믹간의 파절양상은 모든 시편에서 금속표면에 세라믹이 일부 부착된 복합파절(mixed failure) 양상을 보였다.

Clinical Evaluation of Porcelain Fused to Metal Inlay-Retained Bridges

Introduction: Inlay retained bridges represent a conservative approach to restore single missing posterior tooth. Objective: To evaluate the clinical performance and survival rate of inlay retained fixed partial dentures. Materials and methods: A total of 12 patients were included in this clinical study. The patient selection, preparation technique as well as restoration fabrication followed current principles in this science. Patients were evaluated after the final cementation at 3, 6, 12, 24 and 36 months as follow-up period. The evaluation criteria were includes, post-operative sensitivity, de-bonding of the retainer, secondary caries, fracture of the retainer and fracture resistance. Results: A high rate success was observed during the different evaluation periods. Post-operative sensitivity during 3 months and de-bonding of the retainers during the 36 month followup was observed in single independent cases. Conclusions: Inlay retained bridges with adhesive cement appear to be an effective restoration in a single posterior missing tooth. Practitioners should consider its use as an alternative to other restorative options.

REPLACEMENT OF POSTERIOR MISSING TEETH WITH PORCELAIN FUSED TO METAL (PFM) BRIDGE

Porcelain fused to metal (PFM) bridge is the most of treatment that commonly used as a fixed partial dentures. One of the indication for PFM bridge is to replacing the loss of posterior teeth. This case report discussed about the treatment of posterior missing teeth with PFM bridge. Objective: to explain the clinical procedures of PFM bridges to treat the patient with posterior missing teeth. Case report: A 29-years old woman came to prosthodontic clinic in Faculty of Dentistry University of Padjadjaran with chief complaint of right maxillary posterior missing teeth. The treatment planning that have been choosen for this case was the porcelain fused to metal bridge due this excellent characteristic of resistence to mastication force compared with other types of bridge such as all ceramic or all acrylic bridge. Beside that, the aesthetic achievement of this kind of bridges is more excellent than all metal bridges. Disscussion: A spatial analysis, calculation the number of abutment against which used, and selected design bridge very determine the success of this treatment. In addition to that, the clinical procedures consisting of abutment teeth preparation, an accurate impression, and appropriate cementation were needed to get the satisfactory result. Conclusions: The porcelain fused to metal bridge is a appropriate option for posterior missing teeth treatment that fullfil satisfactorical biomechanical and esthetic factors.

Evaluation of a Virtual Reality Simulation System for Porcelain Fused to Metal Crown Preparation at Tokyo Medical and Dental University

The use of virtual reality simulation (VRS) is a new teaching modality in dentistry, and there is scope for further research evaluating its use under different educational programs. The purpose of this study was to evaluate how VRS with or without instructor feedback influenced students' learning and skills related to porcelain fused to metal (PFM) crown preparation. In this study, forty-three dental students in their fifth year of study at Tokyo Medical and Dental University, Tokyo, Japan, were randomly divided into three groups: the first group used VRS (DentSim) with the instructor's feedback (DSF) (n=15), the second group used VRS without the instructor's feedback (DS) (n=15), and the third group neither used features of VRS (NDS) (n=13) nor received the instructor's feedback. All the students performed PFM crown preparation under the same setup once a week for four weeks. Total scores, preparation time, and twelve evaluation items were compared among the three groups and four experiments. The total scores of students in the DSF and DS groups were significantly higher than those in the NDS group. The presence of the instructor did not result in significant difference when VRS was used for training, while it shortened the preparation time at early stages. The results of this study suggested that the use of the VRS system improved student training for PFM crown preparation.

Porcelain fused to metal (PFM) crowns and caries in adjacent teeth.

To assess the discrepancies in marginal integrity and contact points of Porcelain Fused to Metal (PFM) crowns and its association with caries in adjacent teeth. Cross-sectional study. Dental Section of the Aga Khan University Hospital, Karachi, from January to August 2009. Ninety six (96) patients with PFM crowns on maxillary and mandibular premolars and molars were included in this study. Single unit PFM crowns that were part of fixed bridge with at least one natural adjacent tooth were studied. PFM crown with no adjacent tooth or badly broken down teeth were excluded. Marginal integrity, contact points of PFM crowns and caries in adjacent teeth were assessed clinically and radiographically. The data was collected on a structured Proforma. Fisher's exact test was used for statistical analysis. Marginal overhang and marginal gaps on the mesial surfaces of PFM crowns were observed in 17.7% and 13.5% respectively. Tight contact points and open contacts of PFM crowns with adjacent teeth were 15.6% and 17.8% respectively on mesial surfaces. Caries were present in 33.3% and 20% of teeth present mesial and distal to PFM crowns respectively. The association of faulty contact points of PFM crowns with caries in adjacent teeth was found significant (p < 0.001). The association of marginal discrepancy with caries in adjacent teeth was found significant (p = 0.002). A significant association of faulty contact points and margins of PFM crowns with caries in adjacent teeth was found.

Porcelain Fused to Metal Crown as an Abutment of a Metal-Ceramic Resin-Bonded Fixed Partial Denture: A Clinical Report

This clinical report describes a conventional resin-based fixed partial denture for a 42-year-old woman to close an edentulous space in the region of the second maxillary premolar. While the first maxillary molar had been crowned with porcelain fused to metal (PFM) system 10 years ago and the first premolar was intact and sound except for a small carious lesion in the distal aspect. The essential clinical and laboratory procedures are illustrated. Multiple clinical studies document excellent long-term success of resin-bonded fixed partial dentures. In the 1970s, the Rochette resin-bonded fixed partial denture (RBFPD) was introduced. Next, to enhance retention and resistance form of posterior RBFPD preparation of parallel guide surfaces on the interproximal aspects of the adjacent teeth along with rests on the occlusal aspects to counteract dislodging forces was recommended. A 42-year-old woman presented with an extracted left maxillary second premolar. The first maxillary molar had been crowned 10 years ago and the first premolar had a small carious lesion in the mid distal of proximal aspect. To eliminate unnecessary cutting of the PFM of the first molar and crown preparation of the first maxillary premolar, the use of RBFPD was suggested and accepted by the patient. This clinical report described the indication, the selection of a PFM-crowned abutment, and clinical procedures involved in the fabrication of RBFPD that provided a conservative solution for replacement of one posterior tooth. RBFPDs can be used successfully in both the anterior and the posterior regions of the mouth to replace one or two missing teeth. However, the survival rate of RBFPDs is still considerably less than that of conventional fixed partial dentures. The principal reason for failure is debonding of the framework from the abutment tooth. The selection of nonmobile abutment teeth, the preparation design that enhances retention and resistance form, and the tooth bonding technique are critical for success.

Cemented CeraOne® and Porcelain Fused to TiAdapt™ Abutment Single‐Implant Crown Restorations: A 10‐Year Comparative Follow‐Up Study

Long-term data comparing cemented and noncemented single-implant restorations has not been reported. To compare clinical and radiographic performance of single-implant crown restorations made by either directly baked porcelain to custom-made TiAdapt titanium abutments (Nobel Biocare AB, Göteborg, Sweden) (test) or cement crowns onto CeraOne (Nobel Biocare AB) abutments (control) after 10 years in function. Altogether, 35 consecutive patients were provided with 41 turned single Brånemark System implants (Nobel Biocare AB) in the partially edentulous upper jaw. By random, 15 and 20 patients were provided with 18 test and 23 control implant crowns, respectively. Thereafter, clinical and radiographic data were collected and compared between the two groups. None of the implants were found loose during the follow-up period (100%). Few clinical problems were observed, and the overall average marginal bone loss was 0.26 mm (SD 0.64) during 10 years in function. After the final tightening of the crowns, no significant differences were observed between the test and control groups (p > .05). The head of the implants was placed on an average 6.3 mm (SD 2.24) below the cement/enamel junction of the adjacent teeth (range 2.5-10.0 mm). Implants with reported mechanical and/or mucosal problems or placed more apically in relation to the adjacent teeth did not present more bone loss as compared with implants with no problems or placed more coronally, respectively (p > .05). There seems to be no obvious clinical or radiographic differences between the test and control single-implant restorations during 10 years of follow-up. Occasionally, some restorations presented loose abutment screws and/or fistulas during follow-up. This implies a certain need for maintenance where a one-piece single-implant protocol (test) allows both for a simple clinical procedure at placement without cementation problems, as well as for an easy and simple maintenance of installed single implant crowns in long-term function.

Effects of Nitrogen Implantation on the Bonding Strength of Porcelain Fused to Pure Titanium

The present study investigates the effect of nitrogen implantation on the surface of pure titanium on the bonding strength of porcelain and titanium. A series of pure titanium specimens are cut and divided into nitrogen implantation group. The TiN is found in the implantation layer. The bending strength of porcelain-titanium is reinforced after titanium is nitrided.

Cross-sectional TEM Analysis of Porcelain Fused to Gold-coated Titanium

This study investigated the interfacial microstructure between gold-coated titanium and low-fusing porcelain. The square surfaces of cast titanium split rods were sputter-coated with gold using a sputter coater at 40 mA for 1,000 seconds. Specimens were prepared for transmission electron microscopy (TEM) by cutting and polishing two pieces of the gold-coated split-rod specimens, which were glued and embedded in Cu tubes with an epoxy adhesive. TEM observation was also conducted for the gold-coated specimens after degassing and porcelain fusing. Due to the gold coating, intermetallic compounds of Au-Ti formed under the sputtered gold layer after degassing and porcelain fusing. Ti3Au and Ti3Al layers were also observed beneath the Au-Ti intermetallic compound layer. There was good adhesion of porcelain to the Au-Ti compound and Ti oxides without any gaps or formation of a Ti-deficient intermediate layer, which is normally observed at the titanium-porcelain interface. The results of this TEM study suggested that gold-sputter-coating the cast titanium surface produced a Ti-Au intermetallic compound and suppressed the formation of a Ti-deficient intermediate layer, resulting in improved adherence between porcelain and titanium.

Clinical Evaluation of Porcelain Fused to Electroformed Gold Coping Crowns: Preliminary Results after 30-43 Months

Purpose: Porcelain-fused-to-gold copings prepared by the electroforming technique were introduced as an alternative to conventional metal/ceramic crowns. However, there are few clinical studies that have evaluated this technique. The purpose of this study was to prospectively evaluate the clinical performance of Auro Galvano Crowns (AGCs).Methods: One hundred and twenty-seven AGCs were used to treat patients at the Tsurumi University Dental Hospital from October 2002 to December 2003. All the crowns were evaluated using the modified California Dental Association (CDA) quality assessment system at baseline and at all follow-up appointments.Results: A total of 122, 119, and 72 crowns were examined at the 1-, 2-, and 3-year follow-ups, respectively. During the observation period, four crowns were removed because of partial fracture of the veneered porcelain in premolar and posterior teeth. No chips were detected during this observation period. All of the crowns examined were rated as satisfactory according to the modified CDA quality assessment system. During this period, the cumulative survival rate was 96.1%.Conclusion: Within the limitations of this clinical study, AGCs luted with adhesive resin cement functioned satisfactorily with a relatively low fracture rate compared to porcelain-fused-to-metal (PFM) and all-ceramic crowns. Since the observation period was short, long-term observation will be necessary in order to further evaluate these crowns.

Mechanical Properties of Porcelain Fused to Gold Alloy at High Temperature : The Effective Method for Evaluation of Sag-Resistance

Mechanical Properties of Porcelain Fused to Gold Alloy at High Temperature : The Effective Method for Evaluation of Sag-Resistance

Clinical Observation of Porcelain Fused to Metal Crown and Bridge Marginal Fitness of its Crown

Clinical Observation of Porcelain Fused to Metal Crown and Bridge Marginal Fitness of its Crown

Studies on Physical Properties of Porcelain Fused to Metal

Studies on Physical Properties of Porcelain Fused to Metal

Study of bond strength of dental porcelain fused to metal.

SYNOPSIS IN INTERLINGUA UN STUDIO DEL FORTIA ADHESIVE DE PORCELLANA DENTAL FUSIONATE A METALLO.-Pro evalutar le effecto del atmosphera in le furno super le fortia ligatori, 12 specimens pro tests del fortia tensil de metallo describite in Specification No. 14 del ADA esseva preparate con un strato uniforme de material ceramic fusionate al barra. In 3 del specimens le material ceramic esseva fusionate in aere, in 3 in un vacuo, in 3 in oxygeno, e in 3 le nude metallo passava a transverso le cyclo de ignition. Le specimens manipulate sub oxygeno produceva le plus alte valores de fortia ligatori, e le specimens manipulate in vacuo produceva le valores le plus basse.

How to Utilize Porcelain Fused to Gold as a Crown and Bridge Material

How to Utilize Porcelain Fused to Gold as a Crown and Bridge Material

An Improved Porcelain Fused to Gold Bridge

An Improved Porcelain Fused to Gold Bridge