Single implants are a predictable treatment, and immediate loading can be an option with
acceptable survival rates. Clinical and patient-centered outcomes comparing immediate and
delayed protocol of single implants are unclear. The purpose of this study was to assess
complications, satisfaction, and quality of life of patients rehabilitated with delayed and
immediate loading single crowns. An electronic search was conducted in
PubMed/MEDLINE, Scopus, Web of Science, Cochrane Library, and Embase databases up to
February 2023. Only prospective studies, randomized and non-randomized clinical trials
comparing immediate and delayed loading were included. For the quantitative analysis,
dichotomous and continuous variables were evaluated with a 95% confidence interval. A total
of 20 studies were evaluated. No statistically significant difference between protocols was
observed: satisfaction (I2: 0%; P = 0.42), quality of life (I2: 0 %; P = 0.05), biological
complications (I2: 9%; P = 0.17) mechanical complications (I2: 58%; P = 0.84), and survival
rate (I2: 0%; P = 0.38). Subgroup analysis showed significant differences only for marginal
bone loss when immediate implants were placed in the mandible (IÇ: 15%; P = 0.01) and
posterior zone (I2: 0%; P = 0.001). Complications and patient-centered outcomes for
immediate single-implant crowns were comparable to delayed loading. Scientific evidence
showed no significant difference between loading protocols for survival rates. Although
several factors could interfere with the complication events, implant failures, and marginal
bone loss, the subgroup analysis evidenced that only immediate implants placed in the
posterior mandible zone had higher statistically significant mean marginal bone loss.
Keywords: immediate dental implant loading, implant-supported dental prosthesis, patient satisfaction, quality of life, survival rate