共查询到20条相似文献，搜索用时 15 毫秒
1.
Lisa A. Knobloch Peter E. Larsen Paola C. Saponaro Emilie L’Homme-Langlois 《The Journal of prosthetic dentistry》2018,119(5):702-709
Patients with ectodermal dysplasia have abnormalities of 2 or more structures that originate from the ectoderm. The oral manifestations often include the congenital absence of teeth and malformed teeth. This clinical report describes the interdisciplinary care from childhood through the definitive dental rehabilitation completed at skeletal maturation to replace the missing teeth in a patient with ectodermal dysplasia. Treatment began at 9 years of age with an implant-assisted mandibular overdenture to improve function and replace the missing mandibular teeth. Orthodontic treatment for the consolidation of space, composite resin restorations, and interim removable dental prostheses were provided to improve esthetics and replace the missing maxillary teeth. Skeletal growth was monitored, and orthognathic surgery was performed at the cessation of growth. The definitive rehabilitation consisted of a mandibular fixed dental prosthesis supported by dental implants and a maxillary removable dental prosthesis to restore the patient to esthetics and function. 相似文献
2.
Paola C. Saponaro Damian J. Lee Edwin A. McGlumphy 《The Journal of prosthetic dentistry》2017,117(5):587-591
This clinical report describes the management of a fractured 1-piece zirconia stock abutment from an implant with an internal connection using a modified plastic periodontal probe. This minimally invasive approach allows for the retrieval of fractured prosthetic components without causing irreversible damage to the implant’s platform or its internal threads and does not require special equipment or costly instruments. 相似文献
3.
Elif Figen Koçak Yurdanur Uçar Cem Kurtoğlu William M. Johnston 《The Journal of prosthetic dentistry》2019,121(3):510-516
Statement of problem
A good color match combined with a proper translucency match results in excellent esthetics for a metal-free restoration, yet basic color and translucency comparisons between available zirconia systems are not well described.Purpose
The purpose of this in vitro study was to compare the color and translucency of commercially available zirconia materials.Material and methods
Eight specimen disks were formed in each of the single-layer (0.5-mm thick) groups and double-layer (0.5-mm zirconia with 1.0-mm porcelain) groups for each of 5 zirconia-based substructure systems. Colors on black, gray, and white backings were used to obtain CIEDE2000 color differences between the zirconia systems in the layering groups and to obtain relative translucency parameter (RTP) values. Color differences were compared with perceptibility and acceptability thresholds, and comparisons in RTP were made using analyses of variance and the Bonferroni corrected Student t tests (α=.05).Results
The Shrout-Fleiss random set reliability for the duplicate L* determinations was 0.9992, 0.9756 for a*, and 0.9959 for b*. Although some mean color differences were below or at the perceptibility threshold, most differences were at or above the acceptability threshold. For the single-layer configuration, 1 material system had higher RTP values than every other material (P<.001), and another material had lower RTP values than every other material (P<.001).Conclusions
The results of this study present significant differences in both color and translucency among 5 ceramic substrate systems when studied in single layers. Perceivable and often unacceptable differences in color were also found among these materials when layered with porcelain. It is concluded that the esthetics of restorations which use a ceramic substrate is notably affected by the ceramic system used. 相似文献4.
Doğu Ömür Dede Onur Sahin Oğuz Süleyman Özdemir Burak Yilmaz Ersan Celik AySegül Köroğlu 《The Journal of prosthetic dentistry》2017,117(1):138-143
Statement of problem
Lithium disilicate restorations are commonly used, particularly in the anterior region. The color of the underlying composite resin foundation (CRF) and luting cement may negatively affect the color of lithium disilicate ceramic restorations.Purpose
The purpose of this in vitro study was to investigate the effect of CRF and resin cement materials on the color of lithium disilicate ceramics in 2 different translucencies.Material and methods
Twenty disks (11×1.5 mm, shade A2) were fabricated from medium-opacity (mo) (n=10) and high-translucency (ht) (n=10) lithium disilicate (Lds) blocks (IPS e.max Press). Five CRF disks (11×3 mm) were fabricated in 5 different shades (A1, A2, A3, B2, C2) and 30 resin cement disks (11×0.2 mm) in the shades of translucent (Tr), universal (Un=A2), and white-opaque (Wo). Ceramic specimens were placed on each CRF, and the resin cement combination and color was measured with a spectrophotometer. CIELAB color coordinates were recorded, and the color coordinates of both ceramics on the shades of the A2 CRF and resin cement were saved as the control. Color differences (ΔE00) between the control and test groups were calculated. Data were analyzed with 3-way analysis ANOVA and compared with the Tukey HSD test (α=.05).Results
The ΔE00 values were influenced by the shades of the CRF, resin cement materials, and also their interactions (P<.05). The ΔE00 values were not affected by the ceramic type. The ΔE00 values of the Wo cement groups (1.73 to 2.96) were significantly higher than those of the other cement shades (0.88 to 1.29) for each ceramic type and CRF shade (P<.05).Conclusions
Lithium disilicate ceramics in 2 different translucencies were similarly influenced by the color of the underlying cement and CRF. When translucent and universal cement shades were used, the core shade did not affect the final color of the ceramics. White opaque cement caused clinically unacceptable color changes in both ceramics on all shades of CRFs except the C2 CRF and when high translucency ceramic was used on the A2 CRF. These changes were clinically acceptable, but perceptible. 相似文献5.
Geoffrey R. Johnston Faris Z. Jamjoom Damian J. Lee 《The Journal of prosthetic dentistry》2018,119(1):29-32
A technique for the retrieval of wedged implant fragments is described. The technique is suitable for fractured zirconia and metal abutments and titanium bases left behind after fracture or debonding of the custom zirconia abutment from the titanium base of an implant-supported prosthesis. This straightforward, noninvasive, technique facilitates the removal of the fragments or titanium bases without risking damage to the implant, surrounding bone, or soft tissues. 相似文献
6.
Serhat Emre Ozkir Burak Yilmaz Isin Kurkcuoglu Ahmet Culhaoglu Server Mutluay Unal 《The Journal of prosthetic dentistry》2017,117(1):87-92
Statement of problem
Various materials are available to secure implant attachment housings in overdentures. Surface roughness and the adaptation of these materials to the denture base and the housings may increase the microcracks and bacterial adhesion at the interfaces in the long term. The surface characteristics of the interface between the denture base orientation material and the attachment housing have not been extensively studied.Purpose
The purpose of this in vitro study was to evaluate the surface roughness and the adaptation of 5 different housing orientation materials to the housings and the denture base.Material and methods
Fifty-five poly(methyl methacrylate) (PMMA) specimens (15 mm in diameter and 4 mm in height) were prepared with a clearance inside to allow the insertion of overdenture housings. Five different materials were used for housing orientation (Quick Up, Ufi Gel Hard, Tokuyama Rebase II Fast, Meliodent, and Paladent). The specimens were thermocycled 5000 times between 5°C and 55°C. The surface roughness (Ra values) of the specimens was measured with a noncontact profilometer. Scanning electron images were made in order to inspect the PMMA-orientation material-housing interfaces. The Kruskal-Wallis test was used to investigate the differences between the surface roughness values of the orientation materials, and the Iman-Conover test was used for pairwise comparisons (α=.05).Results
The surface roughness values significantly differed between Quick up and Ufi Gel orientation materials only, and Quick up had smaller surface roughness values than Ufi Gel (P=.009). Microcracks were observed among the groups only at the junction of the orientation material and the housing after thermocycling.Conclusions
Ufi Gel Hard showed the roughest surfaces around the overdenture attachment housings. The adaptation between the orientation material and the housing may deteriorate, and increased surface roughness and microcrack formation may be seen around the housings. 相似文献7.
Desheng Sun William A. Brantley Gerald S. Frankel Reza H. Heshmati William M. Johnston 《The Journal of prosthetic dentistry》2018,119(4):650-656
Statement of problem
Although palladium-silver alloys have been marketed for over 3 decades for metal-ceramic restorations, understanding of the corrosion behavior of current alloys is incomplete; this understanding is critical for evaluating biocompatibility and clinical performance.Purpose
The purpose of this in vitro study was to characterize the corrosion behavior of 3 representative Pd-Ag alloys in simulated body fluid and oral environments and to compare them with a high-noble Au-Pd alloy. The study obtained values of important electrochemical corrosion parameters, with clinical relevance, for the rational selection of casting alloys.Material and methods
The room temperature in vitro corrosion characteristics of the 3 Pd-Ag alloys and the high-noble Au-Pd alloy were evaluated in 0.9% NaCl, 0.09% NaCl, and Fusayama solutions. After simulated porcelain firing heat treatment, 5 specimens of each alloy were immersed in the electrolytes for 24 hours. For each specimen, the open-circuit potential (OCP) was first recorded, and linear polarization was then performed from –20 mV to +20 mV (versus OCP) at a rate of 0.125 mV/s. Cyclic polarization was subsequently performed on 3 specimens of each alloy from –300 mV to +1000 mV and back to –300 mV (versus OCP) at a scanning rate of 1 mV/s. The differences in OCP and corrosion resistance parameters (zero-current potential and polarization resistance) among alloys and electrolyte combinations were compared with the 2-factor ANOVA (maximum-likelihood method) with post hoc Tukey adjustments (α=.05).Results
The 24-hour OCPs and polarization resistance values of the 3 Pd-Ag alloys and the Au-Pd alloy were not significantly different (P=.233 and P=.211, respectively) for the same electrolyte, but significant differences were found for corrosion test results in different electrolytes (P<.001 and P=.032, respectively). No significant interaction was found between the factors of alloy and electrolyte (P=.249 and P=.713, respectively). The 3 Pd-Ag silver alloys appeared to be resistant to chloride ion corrosion, and passivation and de-alloying were identified for these alloys.Conclusions
The Pd-Ag alloys test results showed excellent in vitro corrosion resistance and were equivalent to those of the high-noble Au-Pd alloy in simulated body fluid and oral environments. Passivation, de-alloying, and formation of a AgCl layer were identified as possible corrosion mechanisms for Pd-Ag alloys. 相似文献8.
Burak Yilmaz 《The Journal of prosthetic dentistry》2018,119(5):688-692
Computer-aided design and computer-aided manufacturing (CAD-CAM) complete-arch implant-supported fixed prostheses have become popular in recent years and offer several advantages over traditional fabrication techniques. However, they also present challenges, and careful treatment planning is required, particularly for zirconia implant-supported fixed prostheses layered with feldspathic porcelain. This clinical report describes the use of a CAD-CAM high-density polymer implant-supported diagnostic prosthesis to verify the accuracy of the implant impression and evaluate the maxillomandibular relationship, esthetics, and phonetics of the planned CAD-CAM definitive implant-supported fixed prosthesis before CAM processing. 相似文献
9.
Hadi AL-Meraikhi Burak Yilmaz Edwin McGlumphy William A. Brantley William M. Johnston 《The Journal of prosthetic dentistry》2018,119(1):116-123
Statement of problem
Computer-aided design and computer-aided manufacturing (CAD-CAM)-fabricated titanium and zirconia implant-supported fixed dental prostheses have become increasingly popular for restoring patients with complete edentulism. However, the distortion level of these frameworks is not well known.Purpose
The purpose of this in vitro study was to compare the 3-dimensional (3D) distortion of CAD-CAM zirconia and titanium implant-fixed screw-retained complete dental prostheses.Material and methods
A master edentulous model with 4 implants at the positions of the maxillary first molars and canines was used. Multiunit abutments (Nobel Biocare) secured to the model were digitally scanned using scan bodies and a laboratory scanner (S600 ARTI; Zirkonzahn). Titanium (n=5) and zirconia (n=5) frameworks were milled using a CAD-CAM system (Zirkonzahn M1; Zirkonzahn). All frameworks were scanned using an industrial computed tomography (CT) scanner (Nikon/X-Tek XT H 225kV MCT Micro-Focus). The direct CT scans were reconstructed to generate standard tessellation language (STL) files. To calculate the 3D distortion of the frameworks, STL files of the CT scans were aligned to the CAD model using a sum of the least squares best-fit algorithm. Surface comparison points were placed on the CAD model on the midfacial aspect of all teeth. The 3D distortion of each direct scan to the CAD model was calculated. In addition, color maps of the scan-to-CAD comparison were constructed using a ±0.500 mm color scale range.Results
Both materials exhibited distortion; however, no significant difference was found in the amount of distortion from the CAD model between the materials (P=.747). Absolute values of deviations from the CAD model were evident in the x and y plane and less so in the z direction.Conclusions
Zirconia and titanium frameworks showed similar 3D distortion compared with the CAD model for the tested CAD-CAM and implant systems. The distortion was more pronounced in the horizontal and sagittal plane than in the vertical plane. 相似文献10.
Statement of problem
Resin cements are available in various shades from different manufacturers. However, there is no standard for the optical properties of these cements, which may result in differences in the color of translucent ceramic restorations.Purpose
The purpose of this in vitro study was to evaluate the effects of different shades and brands of resin cements on the color of a lithium disilicate ceramic.Materials and methods
Ten ceramic disks (11×1.5 mm, shade A2) were fabricated from lithium disilicate high-translucency blocks. Eighty cement disks (11×0.2 mm) were fabricated from 4 brands (Maxcem; Variolink; Clearfil; and RelyX) of resin cements in translucent and universal (shade A2) shades. Color measurements of ceramic specimens were made without (control) and with each brand/shade of resin cement material (test) with a spectrophotometer, and International Commission on Illumination Lab (CIELab) color coordinates were recorded. Color differences (ΔE00) between the control and test groups were calculated. ΔE00 results were analyzed by 2-way ANOVA and subsequent pairwise testing. Comparisons were performed using the Student t test, and then all P values were corrected with the step-down Bonferroni procedure (α=.05).Results
The effect on the ΔE00 values (P<.001) of the brand and shade of resin cement materials was significant. Both shades of RelyX cement groups had significantly lower and Variolink_translucent cement group had significantly higher ΔE00 results than other brands (P<.05). Only RelyX_translucent and RelyX_universal were significantly different from each other for comparisons within brands (P<.05). The effect of RelyX_universal cement on the ceramic was not visually perceptible (ΔE00≤1.30). Clinically unacceptable results (ΔE00>2.25) were observed only for Variolink_translucent cement (2.36).Conclusions
Same-shade resin cements from different manufacturers had different effects on the color of lithium disilicate ceramic. The effects of different shades of resin cements from the same manufacturer on the color of lithium disilicate ceramic were statistically different for only RelyX, which may also be considered clinically different based on clinical acceptability thresholds for color difference values (ΔE00). Accordingly, this effect may be considered clinically different for Variolink but not clinically different for Maxcem and Clearfil. 相似文献11.
Ryan M. Mizumoto Faris Z. Jamjoom Burak Yilmaz 《The Journal of prosthetic dentistry》2018,119(4):552-559
Statement of problem
In implant dentistry, a variety of techniques are used to manage fractured abutment and prosthetic screws. All of them pose various degrees of difficulty to both the clinician and patient and risk involving damage to the implants and prostheses.Purpose
The purpose of this systematic review was to classify and organize the various reported techniques for managing fractured abutment and or prosthetic screws into a risk-based, decision making tree that could be used to guide the clinician through this difficult and time-consuming clinical procedure.Material and methods
A systematic search of the PubMed/MEDLINE database for articles published before June 2016 was performed by 2 independent reviewers. Studies published in English that described a clinical technique to retrieve or manage a fractured abutment or prosthetic screws were included. Techniques were classified according to risk of irreversible damage to the implant. Low-risk techniques were defined as those involving the use of basic hand instruments and instrument modification; moderate-risk techniques were defined as those involving the use of screw retrieval kits, rotary instruments, and screw modification; and high-risk techniques were defined as those involving modification of the implant. Published techniques were then organized into a decision-making tree.Results
A total of 35 articles were included. The reported techniques ranged from straightforward instrumentation and instrument modification to screw or implant modifications. Seven techniques were considered low risk, 17 moderate risk, and 11 high risk.Conclusions
The proposed risk-based decision tree is a useful tool in helping clinicians choose the most appropriate strategy or sequence of strategies that offers maximum benefit to the patient while minimizing associated risks. 相似文献12.
Fethi Atil Ahmet Culhaoglu Ismail Doruk Kocyigit Zahit Adisen Melda Misirlioglu Burak Yilmaz 《The Journal of prosthetic dentistry》2018,119(1):12-16
This clinical report describes the oral rehabilitation with implant-supported fixed dental prostheses in the maxilla and mandible of a patient with cleidocranial dysplasia. Cone-beam computed tomography and a tilted implant protocol in the mandible helped to establish a conservative approach for bone preservation, prevent surgical complications, enable proper implant positioning to avoid anatomic structures, and support the fixed dental prostheses. 相似文献
13.
W V Campagni 《The Journal of prosthetic dentistry》1985,54(1):13-15
A technique for cementation of a provisional resin splint or crown has been presented. The splint is lubricated with silicone grease and cemented with a noneugenol cement mixed with antibiotic ointment. The grease aids in the complete removal of the cement. The use of a sterile composite resin syringe and preloaded disposable tip allows delivery of the grease to the splint with minimal chance of bacterial cross contamination to the patient. 相似文献
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