RESUMEN
To determine the clinical performance of zirconia abutment (ZA) by comparing with a titanium abutment (TA) and sub?mucosal?modified zirconia abutment. A systematic search was conducted to retrieve eligible randomised controlled trials (RCTs) from Medline, Cochrane Library, SCOPUS, Embase, Web of Science, and Google Scholar. A search was further divided in two parts. Part I comprises eligible RCTs between zirconia abutment and titanium abutment, and part II included RCTs of zirconia abutment with sub?mucosal modified, pink?veneered glass ceramic versus non?veneered zirconia abutment. Esthetic, biological, and abutment survival was a primary outcome, and technical complications were included as an additional outcome. Fifteen eligible RCTs (Part I: N = 9 and Part II: N = 6) were evaluated, and a total of 362 abutments in 364 subjects were analysed for outcome variables. A sub?group meta?analysis reported no significant difference for Esthetic outcome. However, the overall mean (p =0.03) was higher for zirconia group in those of thin gingival phenotype. Spectrophotometric evaluation of peri?implant mucosal Esthetic does not show any significant difference. Similarly, pink?veneered versus non?veneered group reported no significant difference for thin (<2 mm) and thick (>2 mm) mucosal attachment. Biological outcome does not show any significant difference for comparable groups in both parts. There is marginally lower abutment survival for internally connected zirconia abutment (ZA: 95.4% TA: 100%). Zirconia abutment exhibited excellent Esthetic compared to titanium abutment in those of thin gingival phenotype. Sub?mucosa veneering of zirconia abutment with pink glass c