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Objectives: To evaluate the clinical quality of tooth-supported crowns (SCs), implant-supported crowns (ISCs), and fixed dental prosthesis (FDPs) made of a lithium-disilicate glass-ceramic framework material (IPS Empress 2, Ivoclar Vivadent) after long-term use., Materials and Methods: Between 1997 and 1999, 184 restorations (106 SCs, 32 ISCs, 33 FDPs, 13 diverse restorations) were placed in 73 patients. In 2012/2013, all patients with functioning restorations were invited to participate in a clinical follow-up examination. To investigate the clinical quality, modified California Dental Association (CDA) criteria, periodontal health, and the patient's opinion were evaluated., Results: After 14 years on average, 50 restorations were available for evaluation of the CDA criteria and the patient's opinion, and 24 restorations were available for the periodontal health evaluation. Surface, color, anatomic shape, and margin integrity were considered to be in the range of excellence in 54, 78, 96, and 88%, respectively. There were no unacceptable defects. Most patients (64%) were still entirely satisfied with their restorations. Mean probing depths were significantly higher on teeth with tooth-supported Empress 2 restorations than on control teeth (p = 0.0401). No significant relationship was found between surface quality and plaque accumulation (p = 0.9450, generalized linear mixed model) or between surface quality and periodontal probing ≥ 4 mm (p = 0.4184, generalized linear mixed model)., Conclusions: The clinical quality of the Empress 2 restorations that had survived 14 years on average was totally satisfactory with regard to esthetics, design, and patient's opinion. The periodontal health of all-ceramic restored teeth requires further investigation., Clinical Significance: The practitioner's choice of dental materials is based, at best, on long-term experience. With diminishing concerns about the clinical longevity of all-ceramic restorations, the grading of clinical quality based on esthetics, design, periodontal response, and patients' opinions could, nowadays, serve as a measure for the efficiency of dental ceramic.

Objectives: To prospectively evaluate the clinical long-term outcome of 3- to 6-unit fixed dental prostheses (FDPs) made of hot isostatic pressed (HIP) zirconia frameworks, veneered with a synthetic sintering glass-ceramic., Materials and Methods: A total of 27 different restorations were cemented in 21 patients. FDPs were examined with regard to biological and technical complications/failures. Additionally, clinical quality was assessed based on (i) the California Dental Association (CDA) criteria, (ii) the patient's viewpoint according to Hickel, and (iii) periodontal parameters. Descriptive statistics were computed. The Kaplan-Meier estimator was used for the survival and chipping-free rates. Wilcoxon signed ranks test (ordinal/continuous data) or the McNemar test (binary data) was used to describe the periodontal outcome of abutment teeth versus that of the respective control teeth., Results: After a mean observation period of 10.0 ± 2.1 years, the dataset comprised 15 patients with 20 (mainly posterior) FDPs. The 10-year survival rate and 10-year chipping-free rate were 95.0% (CI 86.0-100%) and 78.8% (CI 62.2-99.7%), respectively. Evaluation based on the CDA criteria yielded satisfactory (excellent or acceptable) results for all categories. This was also confirmed by the high level of patient satisfaction. The periodontal health of tissues adjacent to the study teeth was clinically acceptable, but inferior to the ones of control teeth., Conclusions: FDPs made from CAD/CAM-fabricated HIP zirconia ceramic frameworks have a favorable survival rate. However, because damage to the surface texture showed a disproportionate increase after long-term usage, additional long-term studies are required., Clinical Relevance: The outstanding mechanical properties of zirconia-based systems have contributed to the belief that all-ceramics are a reliable material for prosthetic restorations. However, only long-term reports (such as this one) provide more detailed information on actual clinical efficacy.

Aim: The purpose of this in vivo study was quantification of inflammatory reaction to ceramic restorations made from lithium disilicate and zirconia by measurement of the concentration of indicators of inflammation in the gingival crevicular fluid (GCF)., Material and Methods: Patients out of three prospective cohort-studies investigating three different all-ceramic restoration materials for crowns and fixed dental prostheses were included. Patients needed an associated, unrestored tooth to serve as control. GCF samples were taken from the sulcus of the restored teeth and the related controls (n = 59 pairs) and the concentrations of IL1-beta, IL-1ra and aMMP-8, as indicators of inflammation, were determined by use of ELISA tests. Periodontal status was also assessed clinically by measurement of pocket depth (PD), plaque index (PI) and bleeding on probing (BOP)., Results: The concentrations of the inflammation indicators were not significantly different between restored teeth and controls or between lithium disilicate and zirconia restorations (p > 0.05). Furthermore, no significant difference between PD of restored teeth and controls or between groups could be shown., Conclusion: Within the limitation of the study, treatment with all-ceramic restorations did not induce inflammatory reactions in a group of periodontal healthy patients. No differences between the gingiva reactions of lithium disilicate and zirconia restorations could be shown., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

In the present paper, we investigate the behaviour of different dental materials under laser irradiation. We have used e.max Ceram, e.max ZirCAD, and e.max Press dental ceramics and glass ionomer cement Ketac Cem in the present study. The dental ceramics were prepared in the form of samples with thickness of 0.5-2 mm. We used two lasers [solid-state laser (Er:YAG, Fidelis III+, Fotona) and an 810- nm diode laser (FOX, A.R.C)] for the transillumination of ceramic samples. It has been shown that the laser energy transmitted through the ceramic material decreases to 30-40% of the original values along with an increase in the thickness of the irradiated sample. Pigmented ceramic samples show more laser energy loss compared to the samples containing no pigment. We investigated the temperature evolution in composite sandwiched ceramic/cement samples under laser treatment. The increase in the irradiation time and laser power led to a temperature increase of up to 80 °C. The surfaces of irradiated ceramic samples were examined with X-ray photoelectron spectroscopy to evaluate changes in chemical composition, such as a decrease in the C signal, accompanied by a strong increase in the Zr peak for the Er:YAG laser, while the 810-nm diode laser showed no change in the ratio of elements on the surface.

Purpose: Various ceramic implant systems made of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) have become commercially available in recent years. A systematic search of the literature was performed to assess the clinical success of dental Y-TZP implants and whether the osseointegration of Y-TZP is comparable to that of titanium, the standard implant material., Materials and Methods: The internet database MEDPILOT was searched cumulatively for the keywords zircon* and dent* and implant as well as for zircon* and osseointegration. The last search was conducted on January 31st, 2007. Subsequently, the reference lists of the relevant publications were searched. Furthermore, a letter was sent to the 5 identified manufacturers of zirconia dental implants to ask for peer-reviewed publications., Results: Ninety-six articles were found by the search strategy. No controlled clinical studies in humans regarding clinical outcomes or osseointegration could be identified. Clinical data were restricted to case studies and case series. Only 7 animal studies fulfilled the inclusion criteria. Osseointegration was evaluated at 4 weeks to 24 months after placement in different animal models and sites and under different loading conditions. The mean bone-implant contact percentage was above 60% in almost all experimental groups. In studies that used titanium implants as a control, Y-TZP implants were comparable to or even better than titanium implants. Surface modifications may further improve initial bone healing and resistance to removal torque., Conclusions: Y-TZP implants may have the potential to become an alternative to titanium implants but cannot currently be recommended for routine clinical use, as no long-term clinical data are available.

The purpose of this study was to investigate the influences of contaminations and cleaning methods on bonding to dental zirconia ceramic. After saliva immersion and using silicone disclosing agent, airborne-particle abraded ceramic specimens were cleaned with isopropanol (AL), acetone (AC), 37% phosphoric acid (PA), additional airborne-particle abrasion (AA), or only with water rinsing (SS). Airborne-particle abraded specimens without contaminations (CL) were used as control group. For chemical analysis specimens of all groups were examined with X-ray photoelectron spectroscopy (XPS). Plexiglas tubes filled with composite resin were bonded to ceramic specimens using a phosphate-monomer containing composite luting resin. After 3-day water storage, tensile bond strengths (TBS) were tested. XPS analysis of group SS showed the presence of saliva and silicone (Si) contamination on the surface. The ratios of carbon/zirconium and oxygen/zirconium for groups PA and AA were comparable to those ratios obtained for group CL, indicating the removal of the organic saliva contamination. Airborne-particle abrasion and acetone completely removed Si contamination from ceramic surfaces. Isopropanol had little cleaning effect on the two contaminants. TBS (median +/- standard deviation) in MPa of the groups SS (11.6 +/- 3.1), AL (10.0 +/- 2.9), and AC (13.0 +/- 2.8) were statistically lower than those of groups PA (33.6 +/- 5.5), AA (40.1 +/- 3.6), and CL (47.0 +/- 8.1) (p < 0.001), while no differences were found in TBS between groups AA and CL (p > 0.5). Contamination significantly reduced bond strengths to zirconia ceramic. Airborne-particle abrasion was the most effective cleaning method.

Objectives: The purpose of this in vitro study was the evaluation of the bond strength and its durability of two composite resins to zirconia ceramic after using different surface conditioning methods., Methods: Plexiglas tubes filled with composite resin were bonded to zirconia ceramic discs (Cercon) which were either in their original state as supplied by the manufacturer only cleaned in isopropanol or were cleaned with an air-powder-water spray with sodium hydrocarbonate solution or were air abraded (50 microm Al(2)O(3)). Groups of 20 specimens each were bonded either with a conventional composite resin (Variolink II) or with a phosphate monomer (MDP)-containing resin (Panavia F) to the ceramic discs. Subgroups of 10 bonded specimens were stored in distilled water (37 degrees C) for either 3 days or for 150 days. Additionally, the 150 days specimens were thermal cycled 37,500 times. Statistical analyses were conducted with the Wilcoxon rank sum test adjusted by Bonferroni-Holm., Results: The initial tensile bond strength (TBS) for Variolink II ranged from 9.0 to 16.6 MPa and were significantly lower (p< or =0.05) than for Panavia F ranging from 18.7 to 45.0 MPa. Air abrasion resulted in significantly higher TBS (p< or =0.01) than the two other surface conditioning methods. After 150 days storage, only the air abraded specimens bonded with Panavia F showed high bond strengths of 39.2 MPa, whereas most other specimens debonded spontaneously or showed very low bond strengths., Significance: The use of the MDP-containing composite resin Panavia F on air abraded zirconia ceramic can be recommended as promising bonding method.

In a previous clinical study, all-ceramic resin-bonded 3-unit inlay-retained fixed partial dentures (IRFPDs) had a significantly worse outcome in the posterior region than did crown-retained 3-unit FPDs made from the same material. Debonding or fractures were causes of failure. To improve the clinical outcome of IRFPDs, a new framework design was developed: (1) The inlay retainers were made out of CAD/CAM-manufactured zirconia ceramic to improve fracture resistance, and additional veneering of the inlays was omitted. (2) The inlay retainers were completed with a shallow occlusal inlay (1-mm minimum thickness) and an oral retainer wing (0.6-mm minimum thickness). The wings were designed to reduce stress on the inlay retainer caused by torsion forces when the FPD is loaded nonaxially and to increase the enamel adhesive surface area. The pontic was circumferentially veneered with feldspathic porcelain. The clinical and laboratory procedures of this new treatment modality are described, and 2 exemplary clinical cases are presented. This new preparation and framework design might improve the clinical outcome of all-ceramic resin-bonded IRFPDs. However, adequate evidence of long-term safety and efficacy is required before this new design can be recommended for general clinical practice.

Purpose: The purpose of this in vivo study was to evaluate the marginal fit of inlay and crown abutments for fixed partial dentures (FPD) made from a new all-ceramic material., Materials and Methods: Sixteen patients were selected for the study. After abutment preparation, impressions were made and master dies were fabricated. FPDs were made with the experimental heat-pressed lithium-disilicate glass-ceramic following the manufacturer's recommendations. At random, one abutment of each FPD was chosen for evaluation (11 crown and 8 inlay abutments). Impressions of the restoration margins were taken before and after adhesive cementation. Replicas of the abutment margins were investigated by SEM. The marginal discrepancies were evaluated in sections of 200 microm. The highest value of each section was applied, and the mean of all sections of each replica was used for statistical analysis., Results: The median of the marginal discrepancies before cementation was 96 microm for crowns and 89 microm for inlays. After adhesive cementation, the median increased for crowns to 130 microm and for inlays to 92 microm, a significant increase in the marginal discrepancies caused by cementation for crowns, but not for inlays. There were no significant differences between the discrepancies of crowns and inlays before or after cementation., Conclusion: The maximum marginal discrepancies found in this study were between 50 and 265 microm before cementation and between 70 and 285 microm after cementation, with no significant differences between the means for crowns and inlays. Adhesive cementation caused a significant increase of the marginal discrepancies for crown, but not inlay, abutments.

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Purpose: The purpose of this in-vitro study was to evaluate the resin bond strength to pre-etched lithium disilicate ceramic using different cleaning methods after two contamination modes (saliva or saliva and silicone). Materials and Methods: Plexiglas tubes filled with composite resin (MultiCore Flow) were bonded to etched and silanized ceramic disks made of lithium disilicate ceramic (IPS e.max Press) using a luting resin (Multilink Automix). Either etched or unetched ceramic surfaces were contaminated with saliva or with saliva followed by a disclosing silicone. Groups of 16 specimens each were bonded after pretreatment using 4 surface cleaning agents (37% phosphoric acid, 5% hydrofluoric acid, 96% isopropanol, air polishing device with sodium bicarbonate) in different combinations. Before measuring tensile bond strength, specimens were stored for 3 or 150 days with thermocycling. Results: After 150 days of storage, etching of saliva-contaminated surfaces with 5% hydrofluoric acid and/or 37% phosphoric acid provided statistically significantly higher bond strengths (37.9 to 49.5 MPa) than the other cleaning methods (1.7 to 15.5 MPa). After saliva and silicone contamination, etching with 5% hydrofluoric acid provided statistically significantly higher bond strengths (44.5 to 50.3 MPa) than all other cleaning methods (0.3 to 13.5 MPa). Conclusion: Ceramic cleaning methods after try-in procedures have a significant influence on the resin bond strength and are dependent on the type of contamination. Re-etching lithium disilicate ceramic with 5% hydrofluoric acid is most effective in removing contamination with saliva and/or a silicone disclosing medium. [ABSTRACT FROM AUTHOR]