BACKGROUND: Zygomatic implants are an alternative to conventional bone augmentation and implant rehabilitation for the severely atrophic max- illa. Two zygomatic implants can be placed each zygoma and can be successfully immediately loaded. One problem while preparing implant tun- nels for placing zygomatic implants can be the difficulty to control long drills, due to the risk of waving. As a consequence the authors developed two specific tips to be used with a piezoelectric surgery device. AIM/HYPOTHESIS: The aim of this Randomised Controlled Trial (RCT) of split-mouth design was to compare the clinical outcome of site prepara- tion for zygomatic oncology implants using conventional preparation with rotary drills or piezoelectric surgery for placing two zygomatic implants per zygoma. MATERIAL AND METHODS: Twenty edentulous patients with severely atrophic maxillas not having sufficient bone volumes for placing dental implants and <4 mm of bone height subantrally had their hemi-maxillas randomised according to a split-mouth design into implant site preparation with conventional rotational drills or piezoelectric surgery. Two zygomatic oncology implants (unthreaded coronal portion) were placed in each hemi- maxilla. Implants that achieved an insertion torque superior to 40 Ncm were immediately loaded with screw-retained metal reinforced acrylic provisional prostheses. Outcome measures were: prosthesis and implant failures, any complications, time to place the implants, presence of post- operative haematoma, and patient’s preference by independent assessors. All patients were followed up to 1 year after loading. RESULTS: One implant of the conventional drill group did not achieve an insertion torque superior to 40 Ncm since it fractured the zygoma. Two distal oncology implants failed in the same patient (one per group), who was not prosthetically rehabilitated. Six complications occurred at drilled sites and three at piezoelectric surgery sites, the difference being not statistically significant (P = 0.375, Odds Ratio = 4.00, 95%CI of Odds Ratio: 0.45–35.79). Implant placement with conventional drills took on average 14.35 ± 1.76 min and with piezoelectric surgery 23.50 ± 2.26 min, im- plant placement time being significantly shorter with conventional drilling (difference = 9.15 ± 1.69 min, 95%CI: 8.36–9.94 min, P < 0.001). Post- operative haematomas were more frequent at drilled sites (P = 0.001), and 16 patients found both techniques equally acceptable, while four preferred piezoelectric surgery (P = 0.125). CONCLUSIONS AND CLINICAL IMPLICATIONS: Both drilling techniques achieved similar clinical results but conventional drilling required 9 min less and could be used in all instances, though it was more aggressive. These results may be system-dependent, therefore they cannot be generalised to other zygomatic systems with confidence.
Drills versus piezoelectric surgery for placement of zygomatic implants: 1-year split-mouth RCT data
Pietro Felice;Carlo Barausse;Giovanni Zucchelli;
2017
Abstract
BACKGROUND: Zygomatic implants are an alternative to conventional bone augmentation and implant rehabilitation for the severely atrophic max- illa. Two zygomatic implants can be placed each zygoma and can be successfully immediately loaded. One problem while preparing implant tun- nels for placing zygomatic implants can be the difficulty to control long drills, due to the risk of waving. As a consequence the authors developed two specific tips to be used with a piezoelectric surgery device. AIM/HYPOTHESIS: The aim of this Randomised Controlled Trial (RCT) of split-mouth design was to compare the clinical outcome of site prepara- tion for zygomatic oncology implants using conventional preparation with rotary drills or piezoelectric surgery for placing two zygomatic implants per zygoma. MATERIAL AND METHODS: Twenty edentulous patients with severely atrophic maxillas not having sufficient bone volumes for placing dental implants and <4 mm of bone height subantrally had their hemi-maxillas randomised according to a split-mouth design into implant site preparation with conventional rotational drills or piezoelectric surgery. Two zygomatic oncology implants (unthreaded coronal portion) were placed in each hemi- maxilla. Implants that achieved an insertion torque superior to 40 Ncm were immediately loaded with screw-retained metal reinforced acrylic provisional prostheses. Outcome measures were: prosthesis and implant failures, any complications, time to place the implants, presence of post- operative haematoma, and patient’s preference by independent assessors. All patients were followed up to 1 year after loading. RESULTS: One implant of the conventional drill group did not achieve an insertion torque superior to 40 Ncm since it fractured the zygoma. Two distal oncology implants failed in the same patient (one per group), who was not prosthetically rehabilitated. Six complications occurred at drilled sites and three at piezoelectric surgery sites, the difference being not statistically significant (P = 0.375, Odds Ratio = 4.00, 95%CI of Odds Ratio: 0.45–35.79). Implant placement with conventional drills took on average 14.35 ± 1.76 min and with piezoelectric surgery 23.50 ± 2.26 min, im- plant placement time being significantly shorter with conventional drilling (difference = 9.15 ± 1.69 min, 95%CI: 8.36–9.94 min, P < 0.001). Post- operative haematomas were more frequent at drilled sites (P = 0.001), and 16 patients found both techniques equally acceptable, while four preferred piezoelectric surgery (P = 0.125). CONCLUSIONS AND CLINICAL IMPLICATIONS: Both drilling techniques achieved similar clinical results but conventional drilling required 9 min less and could be used in all instances, though it was more aggressive. These results may be system-dependent, therefore they cannot be generalised to other zygomatic systems with confidence.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
