PURPOSE: To evaluate the outcome of 2 versus 4 implants placed flapless in fully edentulous mandibles and immediately restored with metal-resin screw-retained cross-arch prostheses. MATERIALS AND METHODS: Sixty patients from two different centres were randomised: 30 to the allon- 2 group and 30 to the all-on-4 group according to a parallel group design. To be immediately loaded, implants had to be inserted with a minimum torque of 40 Ncm. Outcome measures were prosthesis and implant failures, complications, and marginal bone level changes. RESULTS: Flaps were raised in 18 patients. A total of 2 implants in 2 patients did not reach the planned insertion torque and were immediately replaced by larger diameter ones. One year after loading, no drop-out or implant failure occurred. Eight biomechanical complications occurred in the all-on-2 group versus 8 complications in the all-on-4 group. There were no statistically significant differences for complications between groups. There were no statistically significant differences for marginal peri-implant bone levels between the two groups (estimate of the difference = -0.16; 95%CI -0.40 to 0.08; P (ANCOVA) = 0.074), with both groups losing a statistically significant amount of marginal bone (0.74 mm for all-on-2 implants and 0.58 mm for all-on-4 implants). There were statistically significant differences between the two centres, with more bone being lost for the Bologna centre (0.26 mm versus 1.07 mm). CONCLUSIONS: These preliminary results, up to 1 year after loading, suggest that immediately loaded mandibular cross-arch fixed prostheses can be supported by only 2 dental implants. Longer followups (approximately 10 years) are needed to properly evaluate this therapeutic option.
Cannizzaro G, Felice P, Soardi E, Ferri V, Leone M, Lazzarini M, et al. (2013). Immediate loading of 2(all-on-2) versus 4 (all-on-4) implants placed with a flapless technique supporting mandibular cross-arch fixed prostheses: 1-year results from a pilot randomised controlled trial. EUROPEAN JOURNAL OF ORAL IMPLANTOLOGY, 6, 121-131.
Immediate loading of 2(all-on-2) versus 4 (all-on-4) implants placed with a flapless technique supporting mandibular cross-arch fixed prostheses: 1-year results from a pilot randomised controlled trial.
FELICE, PIETRO;
2013
Abstract
PURPOSE: To evaluate the outcome of 2 versus 4 implants placed flapless in fully edentulous mandibles and immediately restored with metal-resin screw-retained cross-arch prostheses. MATERIALS AND METHODS: Sixty patients from two different centres were randomised: 30 to the allon- 2 group and 30 to the all-on-4 group according to a parallel group design. To be immediately loaded, implants had to be inserted with a minimum torque of 40 Ncm. Outcome measures were prosthesis and implant failures, complications, and marginal bone level changes. RESULTS: Flaps were raised in 18 patients. A total of 2 implants in 2 patients did not reach the planned insertion torque and were immediately replaced by larger diameter ones. One year after loading, no drop-out or implant failure occurred. Eight biomechanical complications occurred in the all-on-2 group versus 8 complications in the all-on-4 group. There were no statistically significant differences for complications between groups. There were no statistically significant differences for marginal peri-implant bone levels between the two groups (estimate of the difference = -0.16; 95%CI -0.40 to 0.08; P (ANCOVA) = 0.074), with both groups losing a statistically significant amount of marginal bone (0.74 mm for all-on-2 implants and 0.58 mm for all-on-4 implants). There were statistically significant differences between the two centres, with more bone being lost for the Bologna centre (0.26 mm versus 1.07 mm). CONCLUSIONS: These preliminary results, up to 1 year after loading, suggest that immediately loaded mandibular cross-arch fixed prostheses can be supported by only 2 dental implants. Longer followups (approximately 10 years) are needed to properly evaluate this therapeutic option.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.