He Cai1, Junyu Chen2, Chunjie Li3, Jian Wang1, Qianbing Wan1, Xing Liang4. 1. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, No. 14, Section 3, South Renmin Road, Chengdu 610041, China; Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, No. 14, Section 3, South Renmin Road, Chengdu 610041, China. 2. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, No. 14, Section 3, South Renmin Road, Chengdu 610041, China; Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, No. 14, Section 3, South Renmin Road, Chengdu 610041, China. Electronic address: junyuchen@scu.edu.cn. 3. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, No. 14, Section 3, South Renmin Road, Chengdu 610041, China; Department of Head and Neck Oncology, West China Hospital of Stomatology, Sichuan University, No. 14, Section 3, South Renmin Road, Chengdu 610041, China. 4. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, No. 14, Section 3, South Renmin Road, Chengdu 610041, China; Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, No. 14, Section 3, South Renmin Road, Chengdu 610041, China. Electronic address: xingliangdent@vip.163.com.
Abstract
OBJECTIVES: The implant abutments, which had their own colour, might cause the discoloration of peri-implant mucosa. We aimed to appraise trails comparing the discoloration of peri-implant soft tissue around zirconia and titanium or golden abutments, the tints of which were vastly different. DATA: We included randomized controlled trials (RCTs), controlled clinical trials (CCTs), cohort studies with patients rehabilitated with zirconia, titanium or golden implant abutments, quantitatively comparing the discoloration of peri-implant soft tissue according to CIE-Lab colour scale. SOURCES: A systematic search was conducted in PubMed, EMBASE, CDSR, and CENTRAL databases without any restriction on September 23, 2017. "Grey" literatures were also searched. A manual search was carried out as well. STUDY SELECTION: Of 584 articles initially retrieved, eight were eligible for inclusion. After data extraction, meta-analyses with mean differences (MDs) and their 95% confidence intervals (CIs) were employed. Moreover, the risk of bias within or across studies was assessed by Cochrane Collaboration's tool for assessing risk, the Newcastle-Ottawa scale, funnel plots, or Egger's test. RESULTS: Four RCTs and four cohort studies were included. Soft-tissue discoloration around zirconia abutments was significantly less likely compared to that around titanium abutments (MD = -1.84; 95% CI = -3.62 to -0.07; P = 0.04 < 0.05) or golden abutments (MD = -0.90; 95% CI = -1.60 to -0.20; P = 0.01 < 0.05). CONCLUSIONS: Zirconia abutments with white tint compared to grey titanium or golden abutments seem to restore a more appropriate colour match between peri-implant mucosa and natural teeth. CLINICAL SIGNIFICANCE: Based on the present evidence, the "nature-like" zirconia abutments should be applied more often in the clinic. PROSPERO REGISTRATION NUMBER: CRD42017075930.
OBJECTIVES: The implant abutments, which had their own colour, might cause the discoloration of peri-implant mucosa. We aimed to appraise trails comparing the discoloration of peri-implant soft tissue around zirconia and titanium or golden abutments, the tints of which were vastly different. DATA: We included randomized controlled trials (RCTs), controlled clinical trials (CCTs), cohort studies with patients rehabilitated with zirconia, titanium or golden implant abutments, quantitatively comparing the discoloration of peri-implant soft tissue according to CIE-Lab colour scale. SOURCES: A systematic search was conducted in PubMed, EMBASE, CDSR, and CENTRAL databases without any restriction on September 23, 2017. "Grey" literatures were also searched. A manual search was carried out as well. STUDY SELECTION: Of 584 articles initially retrieved, eight were eligible for inclusion. After data extraction, meta-analyses with mean differences (MDs) and their 95% confidence intervals (CIs) were employed. Moreover, the risk of bias within or across studies was assessed by Cochrane Collaboration's tool for assessing risk, the Newcastle-Ottawa scale, funnel plots, or Egger's test. RESULTS: Four RCTs and four cohort studies were included. Soft-tissue discoloration around zirconia abutments was significantly less likely compared to that around titanium abutments (MD = -1.84; 95% CI = -3.62 to -0.07; P = 0.04 < 0.05) or golden abutments (MD = -0.90; 95% CI = -1.60 to -0.20; P = 0.01 < 0.05). CONCLUSIONS: Zirconia abutments with white tint compared to grey titanium or golden abutments seem to restore a more appropriate colour match between peri-implant mucosa and natural teeth. CLINICAL SIGNIFICANCE: Based on the present evidence, the "nature-like" zirconia abutments should be applied more often in the clinic. PROSPERO REGISTRATION NUMBER: CRD42017075930.