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Al-Dwairi ZN, Al-Aghbari L, Al-Haj Husain N, Özcan M. Durability of cantilever inlay-retained fixed dental prosthesis fabricated from multilayered zirconia ceramics with different designs. J Mech Behav Biomed Mater 2023; 137:105547. [PMID: 36370641 DOI: 10.1016/j.jmbbm.2022.105547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/24/2022] [Accepted: 10/31/2022] [Indexed: 11/09/2022]
Abstract
PURPOSE The purpose of this in-vitro study was to investigate the effect of framework design on fracture resistance and failure modes of cantilever inlay-retained fixed partial dentures (IRFDPs) fabricated from two multilayered monolithic zirconia materials. MATERIALS AND METHODS Seventy-two natural premolar teeth were prepared as abutments for cantilever IRFDPs using three designs: mesial-occlusal (MO) inlay with short buccal and palatal wings (D1), MO inlay with long palatal wing (D2), MO inlay with long palatal wing and occlusal extension (D3). Full-contoured IRFDPs were fabricated from two monolithic zirconia materials; IPS e.max ZirCAD Prime and Zolid Gen-X. Adhesive surfaces were air-abraded and bonded with MDP-containing resin cement. Specimens were subjected to thermocycling (5-55 °C, 5000 cycles); then, mechanical loading (1.2 × 10⁶ cycles, 49 N). Surviving specimens were loaded until failure in the universal testing machine. All specimens were examined under stereomicroscope, and two samples from each group were evaluated using Scanning Electron Microscope. RESULTS Mean failure loads were not significantly different between different framework designs or between two materials. However, IPS e.max ZirCAD Prime showed significantly higher failure rate than Zolid Gen-X during dynamic fatigue (p = 0.009). Samples with D1 design showed higher debonding rate, D2 failed mainly by fracture of the palatal wing and debonding, and D3 failed mainly by fracture of the abutment tooth. Debonded restorations showed mainly mixed failures. CONCLUSION Cantilever IRFDPs with framework designs that maximize adhesion to enamel exhibited promising results. IPS e.max ZirCAD Prime was more susceptible to fractures with the long palatal wing design.
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Affiliation(s)
- Ziad N Al-Dwairi
- Department of Prosthodontics, Faculty of Dentistry, Jordan University of Science and Technology (JUST), Irbid, Jordan.
| | - Latifah Al-Aghbari
- Department of Prosthodontics, Faculty of Dentistry, Jordan University of Science and Technology (JUST), Irbid, Jordan
| | - Nadin Al-Haj Husain
- Division of Dental Biomaterials, Clinic for Reconstructive Dentistry, University of Zurich, Zurich, Switzerland; Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Mutlu Özcan
- Division of Dental Biomaterials, Clinic for Reconstructive Dentistry, University of Zurich, Zurich, Switzerland
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Becker M, Chaar MS, Garling A, Kern M. Fifteen-year outcome of posterior all-ceramic inlay-retained fixed dental prostheses. J Dent 2019; 89:103174. [PMID: 31362035 DOI: 10.1016/j.jdent.2019.07.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/21/2019] [Accepted: 07/22/2019] [Indexed: 10/26/2022] Open
Abstract
OBJECTIVES To evaluate the long-term clinical outcome of inlay-retained fixed dental prostheses (IRFDPs) made from lithium-disilicate glass-ceramic. MATERIAL AND METHODS Forty-five IRFDPs were placed in 42 patients (21 women, mean age 36.1 years and 21 men, mean age 42.0 years). The IRFDPs replaced 4 premolars and 19 first molars in the maxilla and 4 premolars and 18 first molars in the mandible. All teeth were prepared following a standardized protocol for ceramic inlay restorations. Five of the 45 FDPs were hybrid-retained restorations, i.e. one abutment tooth with an inlay retainer and one with a full crown retainer. All restorations were fabricated from heat-pressed lithium-disilicate ceramic (IPS e.max Press, Ivoclar Vivadent AG). The minimal size of the proximal connector was 16 mm2 (4 mm × 4 mm in height and width) with a minimum occlusal ceramic thickness of 1.5 mm. Hydrofluoric acid etching (5%) and silane application was used for conditioning the bonding surfaces. Standard adhesive luting techniques were performed using a dentin adhesive and a resin composite. Standardized follow-up reports were performed annually. The survival rates were performed using the Kaplan-Meier analysis. RESULTS The mean observation period was 100 months (minimum 4, maximum 234 months). Thirty-three FDPs (73%) failed during the observation period and had to be replaced by other restorations. The Kaplan-Meier survival rate for IRFDPs was 57% after 5 years, 38% after 8 years and 22% after 15 years, while for hybrid-retained FDPs it was 100% after 5 years, 60% after 8 years and also 60% after 15 years. CONCLUSION With the design used in the current, study lithium-disilicate ceramic IRFDP had a high clinical failure rate and cannot be recommended for regular clinical use.
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Affiliation(s)
- Merlind Becker
- Department of Prosthodontics, Propaedeutics and Dental Materials, Christian-Albrechts University, Arnold-Heller Str. 16, 24105 Kiel, Germany.
| | - M Saad Chaar
- Department of Prosthodontics, Propaedeutics and Dental Materials, Christian-Albrechts University, Arnold-Heller Str. 16, 24105 Kiel, Germany
| | - Anne Garling
- Department of Prosthodontics, Propaedeutics and Dental Materials, Christian-Albrechts University, Arnold-Heller Str. 16, 24105 Kiel, Germany
| | - Matthias Kern
- Department of Prosthodontics, Propaedeutics and Dental Materials, Christian-Albrechts University, Arnold-Heller Str. 16, 24105 Kiel, Germany
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Waldecker M, Rues S, Rammelsberg P, Bömicke W. Validation of in-vitro tests of zirconia-ceramic inlay-retained fixed partial dentures: A finite element analysis. Dent Mater 2019; 35:e53-e62. [PMID: 30686709 DOI: 10.1016/j.dental.2019.01.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/13/2018] [Accepted: 01/13/2019] [Indexed: 10/27/2022]
Abstract
OBJECTIVE In the past, discrepancies between laboratory results and clinical behavior have been observed for all-ceramic restorations. This analysis of fracture resistance of zirconia-based inlay-retained fixed partial dentures (IRFPDs) aimed at identifying correlations between an in-vitro test setup and the clinical situation. The effects of tooth material, tooth mobility, restoration design, load direction, and different cements were taken into account. METHODS The in-vitro test model and IRFPD were reverse engineered (Geomagic DesignX) and meshed predominantly with hexahedral elements (approx. 230,000 elements). Homogenous, linear-elastic behavior was assumed for all materials. On the basis of the calculated stresses (ANSYS 18.2) and already known strength distributions for the restorative materials fracture resistance of the complete restoration and force at initial damage (fracture within the veneer) was estimated on the basis of the principal stress hypothesis. Differences depending on the assumed clinical situation and effects of different variables on fracture resistance were evaluated. RESULTS All variables tested in the finite element analysis affected the calculated fracture resistance of the IRFPD. Use of resin teeth led to an underestimation of fracture resistance by up to -57%, whereas fracture resistance of IRFPDs on metal abutment teeth was close to the clinical reference (-6% to +15%). Good correlation between the clinical scenario and that using metal teeth could only be achieved when the natural resilience of the abutment teeth was simulated. SIGNIFICANCE When testing fracture resistance of zirconia-based IRFPDs, metal abutment teeth in combination with simulated tooth resilience can reflect the clinical situation accurately.
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Affiliation(s)
- M Waldecker
- Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Heidelberg, Germany.
| | - S Rues
- Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Heidelberg, Germany
| | - P Rammelsberg
- Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Heidelberg, Germany
| | - W Bömicke
- Department of Prosthodontics, Heidelberg University Hospital, University of Heidelberg, Heidelberg, Germany
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All-ceramic inlay-retained fixed dental prostheses for replacing posterior missing teeth: A systematic review. J Prosthodont Res 2018; 62:10-23. [DOI: 10.1016/j.jpor.2017.06.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 04/14/2017] [Accepted: 06/28/2017] [Indexed: 11/22/2022]
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Alkharrat AR, Schmitter M, Rues S, Rammelsberg P. Fracture behavior of all-ceramic, implant-supported, and tooth-implant-supported fixed dental prostheses. Clin Oral Investig 2017; 22:1663-1673. [PMID: 29196948 DOI: 10.1007/s00784-017-2233-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 09/28/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVES In vitro investigation of the effects of fixed dental prosthesis (FDP) support and loading conditions on the fracture behavior of all-ceramic, zirconia-based FDP veneered with computer-aided design/computer-aided manufacturing (CAD/CAM)-manufactured lithium disilicate ceramic. MATERIALS AND METHODS Based on a model for a 3-unit FDP in the molar region (tooth in region 15, implant in region 17), 16 identical zirconia frameworks were fabricated and veneered with milled lithium disilicate ceramic. Another 16 FDPs were manufactured similarly, using a model in which the tooth was replaced by an implant. The specimens underwent 10,000 thermal cycles between 6.5 and 60 °C and 1,200,000 chewing cycles with a force magnitude of 100 N. All were then subsequently loaded until fracture in a universal testing device. Half of the FDPs were subjected to centric and axial loading on the pontic, the others to eccentric and oblique loading on one cusp of the pontic. RESULTS No failures were observed after artificial aging. Fracture loads of tooth-implant-supported restorations were 1636 ± 158 and 1086 ± 156 N for axial and oblique loading, respectively; implant-supported FDPs fractured at 1789 ± 202 and 1200 ± 68 N, respectively. Differences were significant for load application (P < 0.001) and support type (P = 0.020). For the two types of load application, fracture mode differed substantially: complete fracture was observed for centric and axial loading whereas mixed cohesive/adhesive failure was observed for many FDPs loaded eccentrically and obliquely. CONCLUSIONS The high incidence of chipping of manually veneered implant-supported all-ceramics restorations might be reduced by use of CAD/CAM-manufactured lithium disilicate veneers. CLINICAL RELEVANCE FDPs veneered with lithium disilicate resist occlusal forces of 500 N, irrespective of load application and support type. The fracture resistance of implant-supported FDPs was, however, higher than that of combined tooth-implant-supported FDPs. Their clinical use seems to be justified.
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Affiliation(s)
- Abdul Rahman Alkharrat
- Department of Prosthodontics, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany. .,Department of Prosthodontics, University of Würzburg, Pleicherwall 2, 97070, Würzburg, Germany. .,Department of Prosthodontics, Faculty of Dentistry, Damascus University, Damascus, Syria.
| | - Marc Schmitter
- Department of Prosthodontics, University of Würzburg, Pleicherwall 2, 97070, Würzburg, Germany
| | - Stefan Rues
- Department of Prosthodontics, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Peter Rammelsberg
- Department of Prosthodontics, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
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Gumus HS, Polat NT, Yildirim G. Evaluation of fracture resistance of inlay-retained fixed partial dentures fabricated with different monolithic zirconia materials. J Prosthet Dent 2017; 119:959-964. [PMID: 28965678 DOI: 10.1016/j.prosdent.2017.06.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 06/20/2017] [Accepted: 06/21/2017] [Indexed: 10/18/2022]
Abstract
STATEMENT OF PROBLEM Data are lacking on the fracture resistance of monolithic zirconia inlay-retained fixed partial dentures as a conservative treatment for a single missing tooth. PURPOSE The purpose of this in vitro study was to evaluate the fracture resistance of inlay-retained fixed partial dentures produced from 3 different monolithic zirconia materials and based on 2 preparation types and applications with and without thermocycling. MATERIAL AND METHODS A model with missing right and left mandibular first molars was used for different cavity preparations. A tube-shaped cavity and a box-shaped cavity were prepared. Seventy-two epoxy resin casts were prepared from an additional silicone impression. Twenty-four inlay-retained fixed partial dentures from each monolithic zirconia material (Prettau, Zirkonzahn; Katana, Noritake; and Copran, Whitepeaks) were fabricated for each preparation type and cemented to their epoxy model with dual-polymerizing adhesive resin cement; 50% of all specimens were thermocycled for 10000 cycles. The specimens were subjected to a fracture resistance test using a universal testing machine with a crosshead speed of 0.5 mm/min. Fracture surfaces were examined with scanning electron microscopy (SEM), and a specimen from each group was examined for structural changes with differential thermal analysis (DTA). RESULTS No statistically significant differences in terms of fracture resistance were found among brands with both cavity designs and with and without thermal cycles (P>.05). However, SEM and DTA results showed some changes in monolithic zirconia structure after 1 year of aging. CONCLUSIONS The brands and cavity preparation types for single posterior tooth loss generated similar fracture resistance.
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Affiliation(s)
| | - Nilufer Tulin Polat
- Professor, Department of Prosthodontics, Faculty of Dentistry, Inonu University, Malatya, Turkey
| | - Guler Yildirim
- Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Inonu University, Malatya, Turkey.
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Rathmann F, Bömicke W, Rammelsberg P, Ohlmann B. Veneered zirconia inlay-retained fixed dental prostheses: 10-Year results from a prospective clinical study. J Dent 2017. [DOI: 10.1016/j.jdent.2017.06.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Möllers K, Parkot D, Kirsten A, Güth JF, Edelhoff D, Fischer H. Influence of tooth mobility on critical stresses in all-ceramic inlay-retained fixed dental prostheses: A finite element study. Dent Mater 2012; 28:146-51. [DOI: 10.1016/j.dental.2011.10.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 06/28/2011] [Accepted: 10/31/2011] [Indexed: 10/15/2022]
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Gabbert O, Karatzogiannis E, Ohlmann B, Schmitter M, Karl J, Rammelsberg P. Fracture load of tooth-implant-retained zirconia ceramic fixed dental prostheses: effect of span length and preparation design. Clin Oral Implants Res 2011; 23:719-725. [PMID: 21812819 DOI: 10.1111/j.1600-0501.2011.02191.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Evaluation of the effect of different span length and preparation designs on the fracture load of tooth-implant-supported fixed dental prostheses (TIFDPs) manufactured from yttrium-stabilized zirconia frameworks. MATERIAL AND METHODS Forty-eight TIFDPs were manufactured using a CAD/CAM system and veneered with a press ceramic. Rigidly mounted implants (SLA, diameter 4.1 mm, length 10 mm) in the molar region with a titanium abutment were embedded in PMMA bases pairwise with premolars. All premolars were covered with heat-shrink tubing to simulate physiological tooth mobility. Six different test groups were prepared (a) differing in the preparation design of the premolar (inlay [i]; crown [c]), (b) the material of the premolar (metal [m]; natural human [h]) and (c) the length of the TIFDPs (3-unit [3]; 4-unit [4]). All TIFDPs underwent thermomechanical loading (TCML) (10,000 × 6.5°/60°; 6 × 10(5) × 50 N). The load to fracture (N) was measured and fracture sites were evaluated macroscopically. RESULTS None of the restorations failed during TCML. The mean fracture loads (standard deviations) were 1,522 N (249) for the 3-unit, inlay-retained TIFDPs on a metal abutment tooth (3-im), 1,910 N (165) for the 3-cm group, 1,049 N (183) for group 4-im, 1,274 N (282) for group 4-cm, 1,229 N (174) for group 4-ih and 911 N (205) for group 4-ch. Initial damages within the veneering ceramic occurred before the final failure of the restoration. The corresponding loads were 24-52% lower than the fracture load values. CONCLUSIONS All restorations tested could withstand the mastication forces expected. Fracture-load values for 3- and 4-unit inlay-crown and crown-crown-retained TIFDPs should spur further clinical investigation.
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Affiliation(s)
- Olaf Gabbert
- Department of Prosthodontics, University of Heidelberg, Heidelberg, Germany
| | | | - Brigitte Ohlmann
- Department of Prosthodontics, University of Heidelberg, Heidelberg, Germany
| | - Marc Schmitter
- Department of Prosthodontics, University of Heidelberg, Heidelberg, Germany
| | - Jochen Karl
- Department of Prosthodontics, University of Heidelberg, Heidelberg, Germany
| | - Peter Rammelsberg
- Department of Prosthodontics, University of Heidelberg, Heidelberg, Germany
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Harder S, Wolfart S, Eschbach S, Kern M. Eight-year outcome of posterior inlay-retained all-ceramic fixed dental prostheses. J Dent 2010; 38:875-81. [DOI: 10.1016/j.jdent.2010.07.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Revised: 07/28/2010] [Accepted: 07/29/2010] [Indexed: 10/19/2022] Open
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Abstract
Zirconia is unique in its polymorphic crystalline makeup, reported to be sensitive to manufacturing and handling processes, and there is debate about which processing method is least harmful to the final product. Currently, zirconia restorations are manufactured by either soft or hard-milling processes, with the manufacturer of each claiming advantages over the other. Chipping of the veneering porcelain is reported as a common problem and has been labelled as its main clinical setback. The objective of this systematic review is to report on the clinical success of zirconia-based restorations fabricated by both milling processes, in regard to framework fractures and veneering porcelain chipping. A comprehensive review of the literature was completed for in vivo trials on zirconia restorations in MEDLINE and PubMed between 1950 and 2009. A manual hand search of relevant dental journals was also completed. Seventeen clinical trials involving zirconia-based restorations were found, 13 were conducted on fixed partial dentures, two on single crowns and two on zirconia implant abutments, of which 11 were based on soft-milled zirconia and six on hard-milled zirconia. Chipping of the veneering porcelain was a common occurrence, and framework fracture was only observed in soft-milled zirconia. Based on the limited number of short-term in vivo studies, zirconia appears to be suitable for the fabrication of single crowns, and fixed partial dentures and implant abutments providing strict protocols during the manufacturing and delivery process are adhered to. Further long-term prospective studies are necessary to establish the best manufacturing process for zirconia-based restorations.
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Affiliation(s)
- B Al-Amleh
- Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
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Höland W, Schweiger M, Watzke R, Peschke A, Kappert H. Ceramics as biomaterials for dental restoration. Expert Rev Med Devices 2009; 5:729-45. [PMID: 19025349 DOI: 10.1586/17434440.5.6.729] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Sintered ceramics and glass-ceramics are widely used as biomaterials for dental restoration, especially as dental inlays, onlays, veneers, crowns or bridges. Biomaterials were developed either to veneer metal frameworks or to produce metal-free dental restorations. Different types of glass-ceramics and ceramics are available and necessary today to fulfill customers' needs (patients, dentists and dental technicians) regarding the properties of the biomaterials and the processing of the products. All of these different types of biomaterials already cover the entire range of indications of dental restorations. Today, patients are increasingly interested in metal-free restoration. Glass-ceramics are particularly suitable for fabricating inlays, crowns and small bridges, as these materials achieve very strong, esthetic results. High-strength ceramics are preferred in situations where the material is exposed to high masticatory forces.
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Affiliation(s)
- Wolfram Höland
- Research and Development, Ivoclar Vivadent AG, Bendererstr. 2, FL-9494 Schaan, Liechtenstein.
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Ohlmann B, Rammelsberg P, Schmitter M, Schwarz S, Gabbert O. All-ceramic inlay-retained fixed partial dentures: Preliminary results from a clinical study. J Dent 2008; 36:692-6. [DOI: 10.1016/j.jdent.2008.04.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 04/28/2008] [Accepted: 04/30/2008] [Indexed: 10/22/2022] Open
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Gabbert O, Ohlmann B, Schmitter M, Gilde H, Ruef T, Rammelsberg P. Fracture behaviour of zirconia ceramic cantilever fixed dental prostheses in vitro. Acta Odontol Scand 2008; 66:200-6. [PMID: 18622828 DOI: 10.1080/00016350802241555] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Evaluation of the fracture resistance of all-ceramic cantilever fixed dental prostheses (FDPs) manufactured from zirconia frameworks and veneered with a press ceramic. MATERIAL AND METHODS Two mandibular premolars were prepared either with a box inlay cavity or with a full crown chamfer preparation and then duplicated. 40-three-unit cantilever FDPs replacing one premolar, with a group size of eight for each design, were manufactured. In group i-i the cantilever FDPs were retained by two inlays, in group i-c by an inlay-crown combination, and in group c-c by two crowns. The frameworks in groups i-c-R and c-c-R were reinforced by an additional shoulder on the oral side of the zirconia frameworks. All FDPs were subjected to thermal cycling (TC) and 600,000 cycles of mechanical loading (ML) with 50 N. The load to fracture was measured and fracture sites were evaluated. RESULTS The mean fracture values ranged from 172 N to 792 N. Fracture-strength values were significantly lower for the i-i retained FDPs than for the i-c and c-c combinations. There was no significant effect of the reinforcing shoulder in groups i-c-R and c-c-R. For FDPs with a crown on the terminal tooth, fractures were usually within the distal wall of the distal crown. CONCLUSIONS Inlay-inlay retained cantilever FDPs cannot withstand the mastication forces expected. Fracture load values for inlay-crown and crown-crown-retained FDPs encourage further clinical investigation. The mode of fracture indicates that reinforcement of the distal crown wall might enhance fracture resistance.
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