Clinical longevity and trend analysis of 801 ultrathin ceramic veneers: A clinical cohort study.

STATEMENT OF PROBLEM: Whether ultrathin ceramic veneers are a suitable treatment alternative to conventional ceramic veneers is unclear. PURPOSE: The purpose of this prospective clinical cohort study was to evaluate the efficacy and longevity of nonpreparation and minimally invasive ceramic veneers and the influence of existing restorations and ceramic type and to define the relationship between the number of veneers placed on different teeth and in different locations, as well as age and sex correlations. MATERIAL AND METHODS: A total of 801 veneers were placed on incisors, canines, and premolars on maxillary and mandibular teeth between January 2011 and August 2019 (ABR number: RNN/92/19/KE). Feldspathic or feldspathic and lithium disilicate veneers were made, etched, silanated, and cemented. The restorations were evaluated 2 weeks after placement and then every 6 months by using the modified United States Public Health Service (USPHS) criteria. The relationship between participant age and number of veneers was analyzed by using the Spearman rank coefficient test and the Mann-Whitney U test. Changes in the number of participants and veneers in subsequent years were analyzed based on the Spearman rank correlation coefficient. The trend between the location of veneers and the sex of the participants was analyzed by using the chi-square test for trend. Longevity tables and a survival curve for the veneers were prepared based on the Kaplan-Meier method. The relationships between veneer longevity and the type of ceramic used and the presence of restorations were compared by using the Taron-Ware test (α=.05). RESULTS: The mean longevity of the intact veneers was 8.45 years. Clinical success was 99.7% after 1 year and 97.9% after 4 years; this value remained constant until the end of the study. Most participants were women (n=122; 84.1%), and the mean age was 41 years; median 40 years. The number of veneers placed on mandibular teeth each year increased over the subsequent years. CONCLUSIONS: The longevity of ultrathin veneers after 9 years of observation was not related to the ceramic used or to the presence of a composite resin restoration. Veneers were more commonly placed in middle-aged women and in mandibular anterior teeth.

A prospective comparative analysis of the survival rates of conventional vs no-prep/minimally invasive veneers over a mean period of 9 years.

OBJECTIVES: The present study compares the survival rates of 186 conventional and no-prep/minimally invasive porcelain veneers in 35 patients over a mean period of 9 years. MATERIALS AND METHODS: The veneers were placed on the incisors, canines, and premolars in 35 patients between January 2009 and December 2010. Fourteen patients received 84 conventional veneers, and 21 patients received 102 no-prep/minimally invasive veneers. The restorations were evaluated at baseline and after every 6 months until June 2019 based on modified United States Public Health Service criteria. The data was analyzed by using Wilcoxon-Breslow-Gehan and Taron-Ware tests. Kaplan-Meier survival and success curves were plotted for two groups of veneers. The results were compared by using the log rank test. A test probability of P < .05 was regarded as significant, while a test probability of P < .01 was considered to be statistically significant. RESULTS: The mean survival rate, according to the Kaplan-Meier estimator, was 9.67% for conventional veneers and 100% for the no-prep or minimal prep veneers. A total of ten absolute failures were observed in six patients: eight restoration chipping/fractures, one debonding, and one fracturing of the tooth. Mean success rate time for conventional veneers without absolute or relative failures was 9.32 years, and 10.28 years for no-prep/minimally invasive veneers. CONCLUSIONS: Over a mean observation period of 9 years, the survival rate of no-prep/minimally invasive veneers exceed that of conventional veneers. CLINICAL RELEVANCE: No-prep/minimally invasive veneers appear very effective and should always be considered in certain clinical situations.

Diagnostic value of cone beam computed tomography for recognition of oblique root fractures: An in vitro study.

BACKGROUND: Diagnosis of tooth root fractures is based on radiographic examination, which is not reliable in the case of oblique root fractures. OBJECTIVES: The aim of the study was to evaluate the efficacy of cone beam computed tomography (CBCT) imaging of oblique root fractures. MATERIAL AND METHODS: Twenty-four bovine incisors were used in the study. They were randomly divided into 2 groups: an experimental group with artificially created oblique root fractures and a control group without fractures. The teeth underwent a CBCT evaluation with a CS 9300 cone-beam scanner (Carestream, Rochester, USA) using a 5 × 5 cm field of view with the resolution up to 90 µm, and a dental radiography. The specimens were examined by 2 observers with different job experience. RESULTS: In the CBCT scans, fracture lines were detected in 95.8% of cases (the 1st observer made a proper diagnosis in 100% of cases and the 2nd in 91.7%). Fracture lines were identified on radiographs in 33.3% of roots (the 1st observer was able to see the lines in 41.7% of cases and the 2nd in 25%). The inter-observer agreement was very high (the kappa coefficient for CBCT scans was 1.00 and 0.88 for radiographs). The best diagnostic value was recorded for contiguous slices. CONCLUSIONS: Cone beam computed tomography with a small field of view and high resolution significantly surpasses radiographs in effective imaging of oblique tooth root fractures and should be the method of choice in the diagnosis of these fractures.