Influence of surgical ultrasound used in the detachment of flaps, osteotomy and odontosection in lower third molar surgeries. A prospective, randomized, and "split-mouth" clinical study.

BACKGROUND: As third molar surgery is the most commonly procedure performed in Dentistry and has been accompanied by serious postoperative disorders such as pain, edema and trismus, the study aimed to evaluate if ultrasound device would be able to reduce such postoperative features. The aim of this study was to assess the effects of soft tissue flap elevation, osteotomy and odontosection using piezosurgery versus conventional technique in mandibular third molar extractions. MATERIAL AND METHODS: Twenty patients with impacted mandibular third molars underwent tooth extractions using two different methods. Ten patients were included in the Piezo Flap Group (PFG - the flap was elevated using piezosurgery) and ten patients were part of the Piezo Ostectomy Group (POG - osteotomy and odontosection were carried out with ultrasound tips). The contralateral tooth was included in the Control Group (CG - conventional technique). The patients were evaluated at postoperative periods of 1, 3, 7 and 14-days. The measured parameters were duration of surgery, pain, trismus and swelling. RESULTS: The mean duration of surgery for the PFG was 17.21 minutes (CG 10.07 minutes) and POG was 40.09 minutes (CG 15.97 minutes). There was no statistically significant difference in pain and trismus for any of the postoperative periods evaluated in PFG and POG (p>0.05). There was a statistically significant difference in swelling between the PFG and POG, presenting less swelling at the 3-day postoperative period (p=0.038; p<0,05). However, for the remaining analyzed periods there was no difference (p>0.05). CONCLUSIONS: Piezosurgery for tissue elevation of the surgical flap, osteotomy and dental sectioning in mandibular third molar extraction surgery promoted less edema in the early postoperative stages in mandibular third molar extractions despite the longer surgical duration.

Comparison between piezoelectric surgery and conventional saw in sagittal split osteotomies: a systematic review.

A systematic review of the advantages and disadvantages of piezoelectric surgery in comparison with conventional saws for sagittal split osteotomy (SSO) was performed. Relevant studies published in the last 10 years were identified through a search of the PubMed/MEDLINE, Science Direct, and Embase databases and assessed against predetermined eligibility criteria. The initial search resulted in 1736 articles. After applying the inclusion and exclusion criteria, 12 articles remained. A total of 799 patients with an average age of 27.5 years underwent SSO performed using a saw or ultrasonic device. Results showed that it took longer to perform the osteotomies using an ultrasonic device than using a conventional saw. At ≥6 months of follow-up, neurosensory disturbance was seen in 4.7% of patients who underwent piezoelectric surgery versus 61.6% of patients who underwent surgery in which a conventional saw was used. It was found that the use of piezoelectric surgery in SSO leads to the best outcome regarding neurosensory disturbance when compared to conventional saws (P=0.04) at ≥6 months of follow-up. Further studies are required for the evaluation of the other clinical parameters assessed.

Potential of autogenous or fresh-frozen allogeneic bone block grafts for bone remodelling: a histological, histometrical, and immunohistochemical analysis in rabbits.

Our aim was to compare the wound healing of autogenous bone grafts with that of fresh-frozen allogeneic block bone in rabbits. We used 25 animals. One was killed before the experiment to provide the allogeneic bone, and the remainder were killed at four time points (n=6 in each group). On histometrical analysis there was a significant difference between the two groups only at 45days and between 15 and 45days in the intergroup analysis. However, there was significantly more revascularisation (p<0.05), resorption (p<0.05), and bony replacement (p<0.05) in the autogenous group in the immunohistochemical analysis. In later periods, the autogenous bone was replaced by newly-formed bone in all samples, whereas it was always possible to find regions of devitalised bone in the fresh-frozen allogeneic bone grafts. Autogenous grafts were completely replaced whereas, in the fresh- frozen allogeneic grafts, we found acellular tissue that had been incorporated into the receptor bed interface during the later evaluation times.