Accuracy of single-unit ceramic crown fabrication after digital versus conventional impressions: A systematic review and meta-analysis.

In the present era when interest in digital dentistry is increasing, the published literature is still confusing about whether digital impression provides similar accuracy as provided by a conventional impression for the fabrication of a single-unit ceramic crown. The aim of the study was to systematically review the in vivo studies comparing marginal, axial, and occlusal fit of single-unit ceramic crowns fabricated after digital impressions with the ones fabricated after conventional impressions. The PubMed, Scopus, and Cochrane online databases were searched for studies comparing the digital impression technique with the conventional technique for single-unit ceramic crowns. Data extraction was done for the year of publication, type of study, country, number of patients, impression system (intraoral scanner [IOS] or conventional impression), marginal fit, axial fit, and occlusal fit. Ten studies were included for meta-analysis regarding the discrepancy in marginal fit, axial fit, and occlusal fit. The digital impression proved to be better than the conventional impression. The mean difference for marginal fit was 6.54 µm (heterogeneity P < 0.00001, I2 = 93%), for axial fit 24.69 µm (heterogeneity P = 0.34, I2 = 11%), and for occlusal fit 6.99 µm (heterogeneity P = 0.03, I2 = 59%). The results of meta-analyses suggest that there is no significant difference between the impression systems (marginally favoring digital impression). The digital impression technique provided better marginal and internal fit of single-unit ceramic crowns than the conventional impression technique. The digital workflow using IOS provided a clinically acceptable marginal fit for single-unit crowns.

Reproducibility and validity of anterior implant esthetic indices: A review.

BACKGROUND: The purpose of this review was to narrate about the reproducibility and validity of different indices evaluating esthetic aspects in anterior single implant-supported restorations. MATERIALS AND METHODS: An electronic search of Medline, Scopus, Embase, Cochrane Central, and Web of Science databases was performed using the keywords "dental implants," "anterior esthetics," "esthetic score," and "esthetic index." Besides, a manual search of dental implant journals was carried out. RESULTS: The electronic search revealed 932 titles. After further review, 14 articles fulfilled the eligibility criteria and were included in this review. Because of the heterogeneity of the study designs, interventions, and parameters used for assessment of esthetics, no meta-analysis could be performed. CONCLUSION: Many indices have been proposed for the evaluation of the esthetic aspects of single implant-supported reconstructions in the anterior maxilla. All of them have some advantages and drawbacks that this review pointed out. The evidence level of studies used for the validation of these indices is poor. It is necessary to achieve a consensus on the tools for assessment of the esthetic aspect and perform evidence-based studies to validate an appropriate index.

Prevalence of Tooth Shade and its Correlation with Skin Colour - A Cross-sectional Study.

INTRODUCTION: Aesthetics has become an important issue in modern society. Tooth shade is one of the factors in determining aesthetics. Studies have revealed that tooth shade is influenced by age, gender, eye colour, skin colour and other factors. AIM: The present study was aimed to assess the prevalence of tooth shade and its correlation with skin colour. MATERIALS AND METHODS: A total of 300 subjects aged 18-20 years were evaluated for tooth shade using Vitapan - 3D shade guide. Anterior teeth were checked under natural light and facial skin colour by Lakme liquid foundation make up as a shade guide. Data was analysed using chi square test and spearman's correlation. RESULTS: Out of 300 students, 114 (38.00%) had A2 tooth shade; the least prevalent tooth shade among Chitradurga population was C1 (4.00%). There was a positive correlation between tooth shade and skin colour which was found to be statistically significant (p <0.05). CONCLUSION: The most prevalent tooth shade among Chitradurga population was A2 and least was C1. There was a significant correlation between tooth shade and skin colour with lighter skin tone subjects having lighter tooth shade hence skin colour can be used as a guide for shade selection.