A randomized 5-year clinical evaluation of 3 ceramic inlay systems. All-ceramic two- to five-unit implant-supported reconstructions. A randomized, prospective clinical trial. Three-year clinical comparison of survival of endodontically treated teeth restored with either full cast coverage or with direct composite restoration. Ceramic implant abutments for short-span FPDs: a prospective 5-year multicenter study. Randomized controlled clinical trial of zirconia-ceramic and metal-ceramic posterior fixed dental prostheses: a 3-year follow-up. Alumina ceramic implant abutments used for single-tooth replacement: a prospective 1- to 3-year multicenter study. Survival of three types of veneer restorations in a clinical trial: a 2.5-year interim evaluation. Enamel matrix derivative versus bioactive ceramic filler in the treatment of intrabony defects: 12-month results. Enamel matrix proteins and guided tissue regeneration with titanium-reinforced expanded polytetrafluoroethylene membranes in the treatment of infrabony defects: a comparative controlled clinical trial.
The present follow-up study aimed to evaluate the clinical quality and longevity of 3 ceramic inlay systems and compare them with gold inlays.
                Twenty patients were treated with one Cerec, one Mirage, one Empress, and one gold inlay, respectively, inserted in a randomly selected order in the mandible. The inlays were examined independently by 2 calibrated examiners immediately after and 1, 3, and 5 years after luting. The inlays were rated using the California Dental Association (CDA) quality evaluation system.
                Two Empress inlays required replacement because of fracture between examination (Ex) 1 and Ex 2, and 2 Empress inlays were fractured between Ex 3 and Ex 4. One Cerec inlay had to be recemented after 3 months, and one Cerec inlay fractured between Ex 3 and Ex 4 and was replaced with a gold inlay. Examination showed that the mismatch of color increased from 15% to 50% between Ex 1 and Ex 4 for all ceramic systems. Visible evidence of ditching along the margin increased from 5% at Ex 1 to 70% at Ex 4, and an apparent discoloration of the margin between the tooth and the restoration was seen in 0% to 5% at Ex 1 compared to 30% to 55% at Ex 4.
                Eight percent of the ceramic inlays were fractured during the follow-up period of 5 years. Based on the criteria of the CDA quality evaluation system, 92% of the 60 ceramic inlays and 100% of the 20 gold inlays were rated satisfactory 5 years after luting. The purpose of this study was to evaluate the clinical performance of two to five-unit implant-supported all-ceramic reconstructions and to compare the results of two different all-ceramic systems, Denzir (DZ) and In-Ceram Zirconia (InZ). Eighteen patients were treated with a total of 25 two- to five-unit implant-supported reconstructions. Nine patients were given reconstructions of the DZ system and the other nine reconstructions of the InZ system. The reconstructions were cemented with zinc phosphate cement onto preparable titanium abutments and were evaluated after 6 and 12 months. At the 12-month follow-up, all reconstructions were in function; none had fractured. Superficial cohesive (chip-off) fractures were, however, observed in 6 of the 18 patients (8 of 25 reconstructions). Nine units in the DZ group (in 7 of 13 reconstructions) and one in the InZ group (1 of 12 reconstructions) had chip-off fractures. The difference between the two groups regarding frequency of chip-off fractures was statistically significant (P < 0.01). Marginal integrity was rated excellent at 34 abutments (56%) and acceptable at 27 (44%). Results from this 12-month trial suggest that all-ceramic implant-supported fixed partial dentures of two- to five-units may be considered a treatment alternative. When comparing the two ceramic systems under study, however, this study concludes that the DZ system exhibits an unacceptable amount of veneering porcelain fractures and thus cannot be recommended for the type of treatment evaluated in this trial. Further studies and long-term follow-ups must be performed before the materials and technique can be recommended for general use. Little information exists regarding the outcome of crown build-ups on endodontically treated teeth restored with metal-ceramic crowns or with only a direct-placed composite.
                The aim of this study was to evaluate the clinical success rate of endodontically treated premolars restored with fiber posts and direct composite restorations and compare that treatment with a similar treatment of full-coverage with metal-ceramic crowns.
                Subjects included in this study had one maxillary or mandibular premolar for which endodontic treatment and crown build up was indicated and met specific inclusion/exclusion criteria. Only premolars with Class II carious lesions and preserved cusp structure were included. Subjects were randomly assigned to 1 of the following 2 experimental groups: (1) teeth endodontically treated and restored with adhesive techniques and composite or (2) teeth endodontically treated, restored with adhesive techniques and composite, and then restored with full-coverage metal-ceramic crowns. Sixty teeth were included in the first group and 57 in the second. All restorations were performed by one operator. Causes of failure were categorized as root fracture, post fracture, post decementation, clinical and/or radiographic evidence of marginal gap between tooth and restoration, and clinical and/or radiographic evidence of secondary caries contiguous with restoration margins. Subjects were examined for the listed clinical and radiographic causes of failure by 2 calibrated examiners at intervals of 1, 2, and 3 years. Exact 95% confidence intervals for the difference between the 2 experimental groups were calculated.
                At the 1-year recall, no failures were reported. The only failure modes observed at 2 and 3 years were decementations of posts and clinical and/or radiographic evidence of marginal gap between tooth and restoration. There was no difference in the failure frequencies of the 2 groups (95% confidence interval, -17.5 to 12.6). There was no difference between the number of failures caused by post decementations and the presence of marginal gaps observed in the 2 groups (95% confidence intervals, -9.7 to 16.2 and -17.8 to 9.27).
                Within the limitations of this study, the results upheld the research hypothesis that the clinical success rates of endodontically treated premolars restored with fiber posts and direct composite restorations after 3 years of service were equivalent to a similar treatment of full coverage with metal-ceramic crowns. A prospective, randomized, controlled 5-year multicenter study evaluated the long-term clinical function of CerAdapt ceramic abutments compared to titanium abutments on Brånemark implants supporting short-span fixed partial dentures (FPD).
                Initially, 105 Brånemark implants were placed in a total of 32 patients at three different clinics; 103 implants remained after initial healing. Fifty-three ceramic and 50 titanium abutments were connected to support 36 FPDs, 19 on ceramic and 17 on titanium abutments.
                Thirty patients with 29 FPDs were examined after 5 years. There was a cumulative success rate of 97.2% for FPDs (94.7% for ceramic and 100% for titanium abutment-supported FPDs). One of 53 ceramic and none of 50 titanium abutments failed, giving survival rates of 98.1% and 100%, respectively. There was a mean marginal bone loss of 0.3 mm and 0.4 mm, respectively, for ceramic and titanium abutments. Soft tissues around abutments and adjacent teeth appeared healthy, and no significant differences were recorded for mucosal bleeding and plaque between ceramic and titanium abutments. Crown margins at FPD insertion were positioned as follows: 21% submucosally, 33% at the mucosal margin, and 46% supramucosally. Changes in mucosal level were recorded at 12% of the abutments, with 73% of all changes recorded at ceramic abutments. There was a balance between more or less exposed crown margins during the first 2 years, in contrast to the 2- to 5-year period, when all changes meant less exposed margins.
                Safe long-term functional and esthetic results can be achieved with CerAdapt alumina ceramic abutments on Brånemark implants for short-span FPDs. The aim of this study was to test whether posterior fixed dental prostheses (FDPs) with zirconia frameworks exhibit similar survival rates and technical and biologic outcomes as those with metal frameworks.
                Fifty-nine patients in need of 76 FDPs replacing one to three posterior teeth (molars and premolars) were included in the study. The three- to five-unit FDPs were randomly assigned to 38 zirconia-ceramic and 38 metal-ceramic FDPs. At baseline, 6 months, and 1 to 3 years after cementation, the technical outcome of the reconstructions was examined using the United States Public Health Service (USPHS) criteria. The biologic outcome was analyzed at test (abutment) and control (contralateral) teeth by assessing: probing pocket depth (PPD), probing attachment level (PAL), plaque control record (PCR), bleeding on probing (BOP), and tooth vitality. Radiographs of the FDPs were made. Statistical analysis was performed by applying Kaplan-Meier, Pearson chi-square, Fisher exact, and Mann-Whitney U tests.
                Fifty-three patients with 67 FDPs (36 zirconia-ceramic, 31 metal-ceramic) were examined after a mean observation period of 40.3 +/- 2.8 months. Six patients with 9 FDPs were lost to follow-up. The survival of both kinds of FDPs was 100%. No significant differences regarding the technical and biologic outcomes were found. Minor chipping of the veneering ceramic was found in 25% of the zirconia-ceramic and 19.4% of the metal-ceramic FDPs. Extended fracturing of the veneering ceramic occurred solely in zirconia-ceramic FDPs (C: 8.6%, D: 2.8% [USPHS criteria]). Few biologic complications were found. Both types of FDPs rendered the same mean values for the biologic parameters (mean PPD, PCR, and BOP for zirconia-ceramic FDPs = 2.4 +/- 0.3, 0.1 +/- 0.1, and 0.3 +/- 0.2, respectively; mean PPD, PCR, and BOP for metal-ceramic FDPs = 2.4 +/- 0.3, 0.1 +/- 0.1, and 0.3 +/- 0.2, respectively).
                Zirconia-ceramic FDPs exhibited a similar survival rate to metal-ceramic FDPs at 3 years of function. The aim of the study was to compare results after 1 and 3 years when single crowns supported by CerAdapt (test) ceramic abutments or CeraOne (control) titanium abutments were loaded.
                The material was divided into two groups: in group A, 69 (34 test, 35 control) abutments/crowns from all involved clinics were followed for 1 year; and in group B, 20 (10 test, 10 control) abutments/crowns from one of the clinics were followed for 3 years.
                No implant failed, giving a cumulative success rate of 100% for the implants. Two CerAdapt abutments in group A fractured, giving a cumulative success rate of 93% for the CerAdapt and 100% for the CeraOne abutments after 1 year. No abutment failed in group B, giving a cumulative success rate of 100% both for the CerAdapt and the CeraOne abutments between 1 and 3 years. The CerAdapt fractures might have been due to the fact that the abutments were impaired through too-extensive preparation and/or had been exposed to a too-high bending moment. Almost no marginal bone loss was recorded, indicating a stable bone situation both at CerAdapt and CeraOne abutments on single-tooth implants. Healthy conditions, with a relatively stable level of the periimplant mucosa in relation to the abutment/crown, were recorded for soft tissues both at CerAdapt and CeraOne abutments. Both clinicians and patients rated the esthetic result as excellent for practically all cases.
                The results demonstrate the esthetic possibilities and the safety of single-tooth replacement when accepted treatment concepts are followed and documented components are used. The tested abutments worked well, although the fractured CerAdapt abutments indicate that ceramic abutments are more sensitive to handling procedures than the titanium abutments. In this clinical trial, 180 veneer restorations (VRs) were evaluated. The purpose of the study was to collect survival data and to find possible relations between survival and (1) 'type of VR', (2) 'preparation design', (3) 'operator' and (4) the patient-related variables 'tooth-type' and 'vitality of the tooth'.
                The restorations were provided by seven dentists in 1 12 patients on central and lateral maxillary incisors. Experimental variables were: 'type of VR' (either direct resin composite (DC), indirect resin composite (IC) or porcelain (P)), 'preparation design' (with and without incisal overlap) and 'operator'. Failures were recorded at two levels: absolute failure (need for new restoration) and relative failure (need for repair). Survival was defined at three levels: (1) survival of original restoration (Sr, endpoints: 'absolute' failures), (2) functional survival (Sf, endpoints: 'relative' failures) and (3) overall survival (SO, endpoints: both 'absolute-' and 'relative failures').
                The variable 'type of VR' showed significant influence on Sf and So but not on Sr. Sf and So rates of P, IC and DC were, respectively: Sf-P, 94%; So-P, 94%; Sf-IC, 94%; So-IC, 90%; Sf-DC, 80%; So-DC, 74%. VRs on vital teeth showed a significantly better survival than VRs on non-vital teeth at all survival levels.
                Preparation of the incisal edge for incisal coverage is considered to be unnecessary to assure or improve the strength of VRs. Veneers on non-vital teeth showed higher risk to fail than veneers placed on vital teeth. Porcelain veneers showed the best overall survival. This study examined the clinical efficacy of enamel matrix derivative (EMD) and bioactive ceramic filler (BCF) in the treatment of intrabony periodontal defects and evaluated factors influencing the treatment outcome.
                Thirteen chronic periodontitis patients, 41 to 74 years of age, who had two proximal intrabony defects in different jaw quadrants with > or =3 mm vertical radiographic bone loss were selected for this study. After initial therapy, the sites in each patient were randomly assigned to EMD or BCF treatment. Clinical attachment level (CAL), probing depth (PD), tooth mobility (TM), gingival recession (GR), bleeding on probing, and dental plaque were recorded at baseline and at 6 and 12 months. At surgery, the intrabony component was characterized by recording the number of bony walls, distance in millimeters from the buccal crest (BC) to the most apical point of the defect, distance from the cemento-enamel junction (CEJ) to the BC, and the mesio-distal width of the defect at the level of the bony crest.
                BCF treatment resulted in a significant gain in proximal CAL (P = 0.005) and a reduction in proximal PD at 6 months (P <0.001), but there was no further improvement from 6 to 12 months. Paired comparisons by time for the EMD group revealed a significant reduction in proximal PD at 12 months (P = 0.001), whereas the gain in proximal CAL approached significance (P = 0.056). Mean GR increased significantly from baseline to 6 months in both groups (P = 0.001). Regression analysis revealed that within the EMD group, smoking and TM negatively influenced the gain of attachment, whereas within the BCF group, gingival recession increased with age, increasing CEJ to BC distance, and increasing mesial-distal width of the defect.
                The gain in proximal attachment after treating intrabony defects by flap surgery with BCF was significant (P = 0.004) and twice that following treatment with EMD (P = 0.056). Patient and site variables affected the clinical outcome differently. Several studies have documented the clinical efficacy of guided tissue regeneration (GTR) with non-resorbable expanded polytetrafluoroethylene (ePTFE) membranes and enamel matrix proteins (EMP) in the treatment of infrabony defects. The objective of this controlled clinical study was to compare the clinical outcomes of 3 surgical modalities in the treatment of deep interproximal infrabony defects.
                Ninety (90) defects in 90 healthy subjects affected by chronic periodontitis were assigned to 1 of 3 treatment groups by blocking to prognostic variables. The test group was treated with the application of EMP and the simplified papilla preservation (SPP) technique; the second group was treated with titanium-reinforced ePFTE membranes and the SPP technique; and the third group was treated with the SPP technique used as access flap control procedure. No differences were observed in terms of baseline oral hygiene and defect characteristics among the 3 groups, indicating that the blocking approach was effective. A stringent infection control program was adopted for 1 year.
                The 1-year results indicated that: 1) all treatment modalities resulted in clinically significant improvements in clinical attachment levels (CAL) and reduction in probing depth (PD); 2) a statistically significant treatment effect was demonstrated comparing the EMP test, the membrane control, and the flap control groups in terms of CAL gains; 3) both the EMP test and the membrane control groups showed significant CAL gains compared to the flap control group; 4) a statistically significantly greater amount of CAL gain was demonstrated in GTR-treated compared to EMP-treated patients; 5) deeper residual probing depths but smaller increases in gingival recession were demonstrated following EMP therapy; and 6) smoking habits reduced the clinical outcomes of both regenerative procedures.
                The use of a regenerative procedure is indicated in the treatment of deep vertical bony defects since both the regenerative techniques (GTR and EMD) in the present study resulted in clinically and statistically significant improvements in clinical parameters compared to the access flap procedure. The use of EMP can be helpful in esthetically-sensitive sites and in reducing patient morbidity.
There is no strong evidence available to support any differences in the clinical performance of ceramic inlays and other posterior restorations. There is a limited number of well-designed clinical trials within this research area. Greater attention to the design and reporting of studies should be given to improve the study quality of ceramic restoration trials.