Survival of three types of veneer restorations in a clinical trial: a 2.5-year interim evaluation. Three-year clinical comparison of survival of endodontically treated teeth restored with either full cast coverage or with direct composite restoration. Endodontic complications after plastic restorations in general practice. Six-year follow-up of titanium and high-gold porcelain-fused-to-metal fixed partial dentures. Clinical performance of sealed composite restorations placed over caries compared with sealed and unsealed amalgam restorations. Clinical performance and caries inhibition of resin-modified glass ionomer cement and amalgam restorations. A two-year randomized, controlled clinical evaluation of bonded amalgam restorations. A clinical and histological evaluation of conservative pulpal therapy in human teeth. Cemented versus screw-retained implant-supported single-tooth crowns: a 4-year prospective clinical study.
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. 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. To test the hypothesis that dentine and pulp protection by conditioning-and-sealing is no less effective than using a conventional calcium hydroxide lining.
                A cohort of healthy adults requiring a new or replacement restoration in a posterior tooth was recruited in six general practices. All procedures received local Ethics Committee approval. Exclusion criteria included signs and symptoms of pulp necrosis or inflammation, and patients unable to commit to a long-term trial. Cavity preparations were randomized to receive a calcium hydroxide lining or conditioning-and-sealing with a smear-removing bonding system. Choice of bulk restorative material (composite resin or amalgam) was at the discretion of the dentist. The key outcome measure was evidence of pulpal breakdown identified at unscheduled (emergency) or scheduled recall examinations. Postoperative sensitivity was recorded on 100 mm VAS at 24 h, 4 days and 7 days. Pulp status was assessed at 6, 12, 24 and 36 month recall, and at any emergency recall appointment. The relationship between pre-treatment and treatment variables and pulp breakdown was assessed by logistic regression (P = 0.05).
                A total of 602 teeth were recruited, with comparable numbers of cavities lined (288, 47.8%) or conditioned and sealed (314, 52.2%). The majority (492, 81.7%) were replacement restorations, and amalgam was the most common bulk restorative material (377, 62.6%). A total of 390 (64.8%) restored teeth were reviewed at 6 months, 307 (51%) at 12 months, 363 (60.3%) at 24 months, and 279 (46.3%) at 36 months post-restoration. Sixteen cases of pulp breakdown were identified within 36 months of restoration placement, 11 presenting as emergencies and five detected at routine recall examination. Logistic regression showed that preoperative pain, cavity treatment by lining or conditioning-and-sealing and the use of rubber dam isolation had no association with pulp breakdown. Pulp breakdown was associated with deep or pulpally exposed cavities (P < 0.001, odds ratio 7.8) and with composite rather than amalgam restorations (P = 0.001, odds ratio 2.13). Re-coding to identify teeth with pulp exposures revealed that pulpal exposure was the key determinant of adverse pulp outcomes (P < 0.0001, odds ratio 28.4) and that composite resin restorations were again more likely to be associated with pulp breakdown than amalgam (P = 0.017, odds ratio 3.92).
                Considered within the context of routine primary dental care: Dentists can be confident that pulps will be equally well protected from post-restorative breakdown up to 36 months by calcium hydroxide lining and conditioning-and-sealing with adhesive resins. Residual dentine thickness appears to be a key determinant of pulp responses after restorative dental treatment. In deep and pulpally exposed cavities in posterior teeth, composites were associated with more pulpal breakdown than amalgams. In a randomized clinical study 47 titanium and gold-alloy fixed partial dentures (FPDs) were placed during a 1-year period. In the titanium group (n = 22) all metal substructures were made of unalloyed titanium. The titanium substructures were fabricated by copy milling, spark erosion and laser welding (Procera, Nobelpharma). Ceramic veneering was carried out with Duceratin titanium ceramics (Ducera, Germany). In the control group (n = 25) the high-gold alloy Degudent U (Degussa, Germany) and Vita VMK 68 ceramics (Vita, Germany) were used. The longest observation time was 6 years. Only one FPD had to be removed due to metal-ceramic failure (titanium group). The clinical performance of all 125 porcelain-fused-to-metal (PFM) veneers with respect to the longevity of the metal-ceramic compound was described by Kaplan-Meyer survivor analyses. Relating survival to a completely intact ceramic veneer, the 5-year survivor rate was 84% for titanium and 98% for the high-gold alloy. PFM titanium restorations exhibited a significantly increased risk of metal-ceramic failure. However, concerning defects requiring removal, no significant differences in titanium versus high-gold alloy occurred. There were no significant differences in the survival distributions between crowns and pontics within the two groups. The 2-year clinical evaluations of paired occlusal restorations are presented. Each study participant received a sealed composite restoration placed over a carious lesion and either a traditional outline-form (unsealed) amalgam or an ultraconservative sealed amalgam restoration. Caries was removed before placement of both types of amalgam restorations. No important clinical differences developed among the three groups of restorations. The authors clinically examined two restorative materials to evaluate their effectiveness in Class II restorations in primary molars and their ability to inhibit recurrent caries.
                Forty subjects, each in need of two Class II restorations in primary molars, took part in this study. Each patient received one Class II restoration of resin-modified glass ionomer cement and one of amalgam. The authors evaluated the restorations at six-month, one-year, two-year and three-year recall appointments. On exfoliation, teeth with experimental restorations were retrieved and microscopically examined for inhibition of demineralization at restoration margins.
                The results of the clinical evaluation demonstrated no significant differences between the resin-modified glass ionomer cement restorations and the amalgam restorations (P < .05). Polarized light microscopic examination of the returned teeth that were restored as a part of this study indicated that the resin-modified glass ionomer cement had significantly less enamel demineralization at restoration margins than did amalgam (P < .0001).
                The resin-modified glass ionomer cement functioned clinically as well as amalgam for Class II restorations in primary molars. However, the resin-modified glass ionomer exhibited significantly less enamel demineralization at restoration margins than did amalgam.
                Resin-modified glass ionomer cement restorative material functions well for Class II restorations in primary molars and exhibits less recurrent caries at restoration margins than does amalgam. The clinical performance of adhesively bonded dental amalgam restorations was compared with that of traditionally placed non-bonded control amalgams in a randomized prospective study.
                One-hundred thirteen Class II Dispersalloy amalgams were placed in permanent molars and premolars of 31 (21 males, 10 females) human subjects with their informed consent. By random assignment, 60 amalgam restorations were adhesively bonded using ED Primer and Panavia 21 TC (both Kuraray Co, Japan), and 53 traditional non-bonded restorations were placed. Most preparations involved replacement of defective amalgam restorations. Clinical recalls were conducted by experienced evaluators using modified USPHS criteria for occlusal and proximal anatomic form, occlusal and proximal marginal adaptation, and occlusal and proximal surface roughness.
                For the categories of anatomic form, marginal adaptation, surface quality, and temperature sensitivity, there were no significant differences between bonded and non-bonded amalgam restorations (chi-square analysis, p > 0.05). Three non-bonded restorations were lost at 4, 7, and 24 months from preparations with no deliberate retention.
                After two years' clinical service, there were no failures among the amalgam restorations adhesively bonded using ED Primer and Panavia 21 TC, but three non-bonded restorations failed due to lack of retention. For traditional preparations, adhesively bonded amalgams of the type investigated perform as well as non-bonded amalgams over two years' clinical service. Three intermediary base materials, a zinc oxide-eugenol (Cavitec) and two calcium hydroxide liners (Life and Dycal), were selected at random for use as a base beneath amalgam or composite restorations on humans following complete caries removal. Life and Dycal, selected at random, were also used as direct and indirect pulp capping agents as clinically indicated. Clinical evaluations of signs and symptoms were made before treatment and at one-week, six-month, and one-year intervals following treatment. Histological evaluations were performed on three complete caries removal teeth and 18 direct pulp capping teeth six months following treatment. No significant differences in clinical symptomatology resulted between the materials in the complete caries removal group or the indirect and direct pulp capping groups. The purpose of this controlled prospective clinical study was to compare cemented and screw-retained implant-supported single-tooth crowns followed for 4 years following prosthetic rehabilitation with respect to peri-implant marginal bone levels, peri-implant soft tissue parameters, and prosthetic complications.
                Twelve consecutive patients were selected from a patient population attending the Implantology Department at the University of Padova. They all presented with single-tooth bilateral edentulous sites in the canine/premolar/molar region with adequate bone width, similar bone height at the implant sites, and an occlusal scheme that allowed for the establishment of identical occlusal cusp/fossa contacts. Each patient received 2 identical implants (1 in each edentulous site). One was randomly selected to be restored with a cemented implant-supported single-tooth crown, and the other was restored with a screw-retained implant-supported single-tooth crown. Data on peri-implant marginal bone levels and on soft tissue parameters were collected 4 years after implant placement and analyzed to determine whether there was a significant difference with respect to the method of retention (cemented versus screw-retained).
                All patients completed the study. All 24 implants survived, resulting in a cumulative implant success rate of 100%. Statistical analysis revealed no significant differences between the 2 groups with respect to peri-implant marginal bone levels and soft tissue parameters.
                The data obtained with this study suggested that the choice of cementation versus screw retention for single-tooth implant restorations is likely not based on clinical results but seems to be based primarily on the clinician's preference.
                Within the limitations of this study, the results indicate that there was no evidence of different behavior of the peri-implant marginal bone and of the peri-implant soft tissue when cemented or screw-retained single-tooth implant restorations were provided for this patient population.
There is no reliable evidence to show a benefit of one type of veneer restoration (direct or indirect) over the other with regard to the longevity of the restoration.