Systematic review and meta-analysis of welding procedures in one-piece cast implant-supported frameworks

• Published in: Brazilian oral research Vol. 33; p. e110
• Main Authors: Gomes, Jéssica Marcela de Luna, Moraes, Sandra Lúcia Dantas de, Lemos, Cleidiel Aparecido Araujo, Cruz, Ronaldo Silva, Oliveira, Hiskell Francine Fernandes E, Pellizzer, Eduardo Piza
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Pesquisa Odontológica - SBPqO 01.01.2019; Sociedade Brasileira de Pesquisa Odontológica
• Subjects: Dental Casting Technique; Dental Implants; Dental Marginal Adaptation; Dental Prosthesis Design; Dental Prosthesis, Implant-Supported - methods; Dental Soldering - methods; Dentistry; DENTISTRY, ORAL SURGERY & MEDICINE; Humans; Prosthesis Fitting; Welding; Welding - methods; Welding; Dental Implants
• ISSN: 1806-8324; 1807-3107; 1807-3107
• DOI: 10.1590/1807-3107BOR-2019.VOL33.0110

The objective of this systematic review and meta-analysis was to evaluate the effect of welding techniques on implant-supported prostheses and determine whether they contribute to a better adaptation compared with a one-piece cast. A search was conducted using the PubMed/MEDLINE, Embase, and Cochrane Library databases, and articles published until November 2017 were obtained from these databases. This review followed the PRISMA criteria and is registered on the PROSPERO platform (CRD42017081865). The PICO question was "Do welding procedures in one-piece cast implant-supported frameworks influence implant/abutment-framework marginal misfits?" Eleven studies were selected for a qualitative analysis, and seven studies were selected for a quantitative analysis. A total of 189 specimens were fabricated using different materials (cp-Ti, Ni-Cr, Cr-Co, and noble alloys), and welding techniques such as laser welding, conventional welding, tungsten inert gas, and brazing were applied. A vertical marginal misfit was measured using an optical microscope, a stereomicroscope, and/or a scanning electron microscopy. The qualitative analysis in the studies demonstrated a positive effect of the welding techniques on the adaptation of the infrastructures. The meta-analysis confirmed the results (p < 0.00001; MD: -36.14; 95%CI: -48.69 to -23.59). Within the limitations of this study and regarding the heterogeneity of the samples, we conclude that the soldering point technique is effective for obtaining relatively low values of marginal misfit, with laser welding as the most effective technique. However, additional studies were recommended due to the heterogeneity of different variables (alloys, connection, and misfit evaluation) in the included studies.