BACKGROUND: Nowadays the majority of dental implants sold on the market are characterised by surfaces which have been roughened using different technologies, in order to increase the bone-to-implant contact area, with the aim of higher success rates, however there is not yet any reliable clinical evidence to substantiate this, although trends of early success rates are in favour of implants with roughened surfaces. On the contrary, data suggests that after 3 years in function, implants with a very rough surface have a 20% increased risk of being affected by peri-implantitis. The difficulties in the treatment of peri-implantitis and the uncertainty of the long-term prognosis of implants affected by peri-implantitis cast some doubts on the long-term outcome of implants, especially of implants with very roughened surfaces, making the use of implants with machined surfaces interesting once again, although with a more aggressive design aimed at achieving higher insertion torques. AIM/HYPOTHESIS: The aim of this randomised controlled trial of parallel group design was to compare the effectiveness of implant-supported total prostheses supported by four to eight immediately loaded dental implants with a rough surface versus implants with a machined/turned surface. The test hypothesis was that there were no differences between implants with machined and roughened surfaces against the alternative hypothesis of a difference. MATERIAL AND METHODS: Fifty edentulous or to-be-rendered edentulous patients requiring an implant-supported cross-arch prosthesis, were randomised either to receive four to eight implants (iRES SAGL, Lugano, Switzerland) with a roughened surface (25 patients) or with a machined/turned surface (25 patients). Provisional metal-reinforced acrylic prostheses were delivered 48 h after implant placement. Provisional prostheses were replaced after 4 months, by definitive screw-retained metal-resin cross-arch restorations. Outcome measures were prosthesis and implant failures, any complications and peri-implant marginal bone level changes. Patients were followed up to 1 year after loading. All data analysis was carried out according to a pre-established analysis plan. The patient was the statistical unit of the analyses. Differences in the proportion of patients with prosthesis failures, implant failures and complications were compared between groups using the Fisher’s exact probability test. Paired t-tests were used to compare the mean radiographic values at implant placement, and 1-year after loading. Sample t-tests were used to com- pare mean radiographic marginal bone level changes between groups. All statistical comparisons were conducted at the 0.05 level of significance. RESULTS: One year after loading no patient dropped out. No prosthesis failed, but two machined implants were found to be mobile at definitive impression taking in 1 patient (Fisher’s exact test: P = 0.312; difference in proportions = 4%; 95% Cl: 10 to 18). No complications occurred. Both groups presented a significant peri-implant marginal bone loss at 1 year after loading (P < 0.0001), 0.64 mm for rough implants and 0.68 mm for turned implants, respectively, with no statistically significant differences between the two groups (P = 0.482; mean difference = 0.04 mm; 95% Cl: 0.17 to 0.25). CONCLUSIONS AND CLINICAL IMPLICATIONS: Up to 1 year after immediate loading, both implant surfaces provided good and similar results, however, the only two implants which early failed in the same patient had a machined surface. However, these preliminary results must be confirmed by larger trials with longer follow-ups.
Immediately loaded machined versus rough surface dental implants in edentulous jaws: a 1-year post-loading randomised controlled trial.
BARAUSSE, CARLO;FELICE, PIETRO
2016
Abstract
BACKGROUND: Nowadays the majority of dental implants sold on the market are characterised by surfaces which have been roughened using different technologies, in order to increase the bone-to-implant contact area, with the aim of higher success rates, however there is not yet any reliable clinical evidence to substantiate this, although trends of early success rates are in favour of implants with roughened surfaces. On the contrary, data suggests that after 3 years in function, implants with a very rough surface have a 20% increased risk of being affected by peri-implantitis. The difficulties in the treatment of peri-implantitis and the uncertainty of the long-term prognosis of implants affected by peri-implantitis cast some doubts on the long-term outcome of implants, especially of implants with very roughened surfaces, making the use of implants with machined surfaces interesting once again, although with a more aggressive design aimed at achieving higher insertion torques. AIM/HYPOTHESIS: The aim of this randomised controlled trial of parallel group design was to compare the effectiveness of implant-supported total prostheses supported by four to eight immediately loaded dental implants with a rough surface versus implants with a machined/turned surface. The test hypothesis was that there were no differences between implants with machined and roughened surfaces against the alternative hypothesis of a difference. MATERIAL AND METHODS: Fifty edentulous or to-be-rendered edentulous patients requiring an implant-supported cross-arch prosthesis, were randomised either to receive four to eight implants (iRES SAGL, Lugano, Switzerland) with a roughened surface (25 patients) or with a machined/turned surface (25 patients). Provisional metal-reinforced acrylic prostheses were delivered 48 h after implant placement. Provisional prostheses were replaced after 4 months, by definitive screw-retained metal-resin cross-arch restorations. Outcome measures were prosthesis and implant failures, any complications and peri-implant marginal bone level changes. Patients were followed up to 1 year after loading. All data analysis was carried out according to a pre-established analysis plan. The patient was the statistical unit of the analyses. Differences in the proportion of patients with prosthesis failures, implant failures and complications were compared between groups using the Fisher’s exact probability test. Paired t-tests were used to compare the mean radiographic values at implant placement, and 1-year after loading. Sample t-tests were used to com- pare mean radiographic marginal bone level changes between groups. All statistical comparisons were conducted at the 0.05 level of significance. RESULTS: One year after loading no patient dropped out. No prosthesis failed, but two machined implants were found to be mobile at definitive impression taking in 1 patient (Fisher’s exact test: P = 0.312; difference in proportions = 4%; 95% Cl: 10 to 18). No complications occurred. Both groups presented a significant peri-implant marginal bone loss at 1 year after loading (P < 0.0001), 0.64 mm for rough implants and 0.68 mm for turned implants, respectively, with no statistically significant differences between the two groups (P = 0.482; mean difference = 0.04 mm; 95% Cl: 0.17 to 0.25). CONCLUSIONS AND CLINICAL IMPLICATIONS: Up to 1 year after immediate loading, both implant surfaces provided good and similar results, however, the only two implants which early failed in the same patient had a machined surface. However, these preliminary results must be confirmed by larger trials with longer follow-ups.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
