Giovanna Iezzi1, Vittoria Perrotti1, Pietro Felice2, Carlo Barausse2, Adriano Piattelli1,3,4, Massimo Del Fabbro5,6. 1. Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara "Gabriele D'Annunzio", Chieti, Italy. 2. Oral Surgery, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy. 3. Biomaterials Engineering, Catholic University of San Antonio de Murcia (UCAM), Murcia, Spain. 4. Fondazione Villaserena per la Ricerca, Città Sant'Angelo, Pescara, Italy. 5. Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy. 6. Dental Clinic, IRCCS Orthopedic Institute Galeazzi, Milan, Italy.
Abstract
PURPOSE: To compare clinical and radiographic outcomes of <7 mm short (SH) implants inserted in native bone vs longer (ST) implants placed in vertically augmented partially edentulous posterior jaws. A further aim was to evaluate if the residual bone dimension plays a role in the outcomes of SH and extra-SH implants. MATERIALS AND METHODS: This review was registered with PROSPERO. An electronic literature search was performed on PubMed, Scopus and Web of Science. Randomized controlled trials (RCTs) with at least 1-year follow-up, comparing fixed prostheses supported by SH vs ST implants in augmented sites were included. Marginal bone level (MBL) changes, implant survival rate, and complications were evaluated through a meta-analysis. Subgroup analysis was performed dividing the SH implants according to length at each follow-up (1-, 3-, 5-year of function). RESULTS: Twenty-five articles fulfilled the inclusion criteria, featuring a total of 650 SH implants placed in 415 patients and 685 ST implants placed in 403 patients. There was a trend for a significantly lower MBL associated with SH implants respect to ST implants at each follow-up, whilst there was no evidence of a difference in failure rates between SH and ST implants, for any SH length considered and at any follow-up. There was evidence for a lower incidence of complications in favor of SH implants at both 1-year (P < .0001) and 3-year follow-up (P = .01), while at 5-year follow-up there was no evidence of a difference between SH and ST groups (P = .30). CONCLUSION: SH implants supporting partial fixed rehabilitations represent a valuable alternative to augmentation procedures in the medium term. While the performance of implants at least 5-mm long is well documented, more studies with at least 5-year follow-up are needed to confirm the promising outcomes observed with <5 mm-long fixtures.
PURPOSE: To compare clinical and radiographic outcomes of <7 mm short (SH) implants inserted in native bone vs longer (ST) implants placed in vertically augmented partially edentulous posterior jaws. A further aim was to evaluate if the residual bone dimension plays a role in the outcomes of SH and extra-SH implants. MATERIALS AND METHODS: This review was registered with PROSPERO. An electronic literature search was performed on PubMed, Scopus and Web of Science. Randomized controlled trials (RCTs) with at least 1-year follow-up, comparing fixed prostheses supported by SH vs ST implants in augmented sites were included. Marginal bone level (MBL) changes, implant survival rate, and complications were evaluated through a meta-analysis. Subgroup analysis was performed dividing the SH implants according to length at each follow-up (1-, 3-, 5-year of function). RESULTS: Twenty-five articles fulfilled the inclusion criteria, featuring a total of 650 SH implants placed in 415 patients and 685 ST implants placed in 403 patients. There was a trend for a significantly lower MBL associated with SH implants respect to ST implants at each follow-up, whilst there was no evidence of a difference in failure rates between SH and ST implants, for any SH length considered and at any follow-up. There was evidence for a lower incidence of complications in favor of SH implants at both 1-year (P < .0001) and 3-year follow-up (P = .01), while at 5-year follow-up there was no evidence of a difference between SH and ST groups (P = .30). CONCLUSION: SH implants supporting partial fixed rehabilitations represent a valuable alternative to augmentation procedures in the medium term. While the performance of implants at least 5-mm long is well documented, more studies with at least 5-year follow-up are needed to confirm the promising outcomes observed with <5 mm-long fixtures.