Characterisation of bone following ultrasonic cutting

Piezoelectric Bone Surgery. Overview in Applications and Proof of Feasibility in Hand and Plastic Surgery

PURPOSE

Piezoelectric bone surgery was already extensively used in a number of surgical procedures ranging from dental to maxillofacial surgery. The authors aimed to determine whether piezosurgery was suitable and advantageous for performing osteotomies in Hand and Plastic reconstructive surgery.

METHODS

The authors overviewed a variety of applications for Piezosurgery^® Device, from Mectron, in bone reconstructive surgery with over the last 8 years. An overall number of 156 bone cutting procedures in adults and children was described at the phalanges, metacarpal bones and distal radius level, as well as in bone graft harvesting and bone remodeling following carpal scaphoid nonunion, scapho-lunate bone-ligament-bone reconstruction and fibula free flap in maxillofacial defects.

RESULTS

The consolidation rate was 87.5% in scaphoid nonunion grafting and fixation. Bone healing was achieved in all other cases. No intra-operative complications were recorded.

CONCLUSION

Piezosurgery^® allowed high precision in bone cutting as well as custom-made graft and surface roughness were obtained, while preserving nerves, vessels and tendons integrity. The instrument may be handling moved into the surgical space in absence of vibrations, with a clear view onto the bone. The mechanical and biological characteristics of the piezoelectrical effect perfected this technique as an effective and useful instrument in Hand and Plastic surgery. The selective bone cutting properties avoided injuries to the surrounding soft tissues and thermal damage of the bony cells. Best advantages were described in feasibility and flexibility for intra-articular osteotomies, custom-made grafts and reconstructive microsurgical techniques.

Bone Healing Evaluation Following Different Osteotomic Techniques in Animal Models: A Suitable Method for Clinical Insights

Osteotomy is a common step in oncological, reconstructive, and trauma surgery. Drilling and elevated temperature during osteotomy produce thermal osteonecrosis. Heat and associated mechanical damage during osteotomy can impair bone healing, with consequent failure of fracture fixation or dental implants. Several ex vivo studies on animal bone were recently focused on heating production during osteotomy with conventional drill and piezoelectric devices, particularly in endosseous dental implant sites. The current literature on bone drilling and osteotomic surface analysis is here reviewed and the dynamics of bone healing after osteotomy with traditional and piezoelectric devices are discussed. Moreover, the methodologies involved in the experimental osteotomy and clinical studies are compared, focusing on ex vivo and in vivo findings.

Role of Piezo Surgery and Lasers in the Oral Surgery Office

Surgical adjunctive instruments and devices are now available for the up-to-date dental/oral surgical office to help mitigate possible surgical complications. Both the laser and Piezo instruments are unique devices that can offer the clinician certain advantages that may prove beneficial in the treatment of his or her patients.

Cortical Piezo-Puncture as a Minimally Invasive Method for Reducing MiniScrew Implant Insertion Torque: A Preliminary in vitro Study

Objective

The objective of this study was to determine the effect of cortical piezo-puncture (CPP) on maximum insertion torque (MIT), maximum removal torque (MRT), and maximum axial load (MAL) during the insertion of self-drilling miniscrew implants (MSI), in an experimental model with proximal epiphysis of bovine tibia.

Materials and Methods

A comparative study was conducted using two groups of 20 self-drilling MSI inserted in intact bone (control group) and in bone with previous CPP (experimental group). MIT, MRT, and MAL of the 20 mini implants of each group were measured. Using SPSS software, Student’s t-test was applied to compare MIT and MRT and the U-test Mann–Whitney test was applied to compare MAL in both groups as well as Pearson and Spearman correlation.

Results

In the experimental group, average values of 12.85 (±4,32) Newton x centimeters (Ncm), 13.7 (±4,54) Ncm, and 22,474 (±895,95) gF for MIT, MRT, and MAL were found, respectively. In the control group, average values found for MIT, MRT, and MAL were 20.2 (±4,7) Ncm, 22.3 (±5,17) Ncm, and 4688,7 (±320,18) gF, respectively. Statistically significant differences were observed in MIT, MRT, and MAL between control and experimental groups (P < 0,001).

Conclusions

CPP before insertion of orthodontic MSI in bovine tibia significantly reduces MIT, MRT, and MAL.

Conventional Drilling Versus Piezosurgery for Implant Site Preparation: A Meta-Analysis

The aim of this study was to evaluate if the stability of dental implants varies between dental implants placed by piezosurgery compared with those placed by conventional drilling. An electronic search in MEDLINE, SCOPUS, and the Cochrane Library was undertaken until August 2016 and was supplemented by manual searches and by unpublished studies at OpenGray. Only randomized controlled clinical trials that reported implant site preparation with piezosurgery and with conventional drilling were considered eligible for inclusion in this review. Meta-analyses were performed to evaluate the impact of piezosurgery on implant stability. Of 456 references electronically retrieved, 3 were included in the qualitative analysis and quantitative synthesis. The pooled estimates suggest that there is no significant difference between piezosurgery and conventional drilling at baseline (weighted mean differences [WMD]: 2.20; 95% confidence interval [CI]: -5.09, 9.49; P = .55). At 90 days, the pooled estimates revealed a statistically significant difference (WMD: 3.63; 95% CI: 0.58, 6.67, P = .02) favoring piezosurgery. Implant stability may be slightly improved when osteotomy is performed by a piezoelectric device. More randomized controlled clinical trials are needed to confirm these findings.

Physics and Histologic Evaluation of Rotary, Ultrasonic, and Sonic Instruments

Rotary instruments (RIs) are the most commonly used to perform osteotomies in many fields of medicine. Owing to a new interest in performing a minimally invasive surgery, over last fifteen years new devices have been used in oral surgery such as ultrasonic instruments (UIs) and, lately, sonic instruments (SIs). Nowadays, bone preservation and regeneration are paramount in many clinical situations and, consequently, it is crucial to rely upon instruments, which cause the least tissue damage during the surgery. Concerning SIs, there is still few information about workload to be applied and related temperature increases; furthermore, there are no comparative in-vivo studies, which analyze the thermal and mechanical effects on bone. Thus, SIs have been compared with UIs and RIs in terms of heat generation, operating time, accuracy, and tissue damage. Decalcification and sectioning procedure resulted in no significant differences between the applied instruments in terms of bone damage. RIs resulted more efficient than UIs (P < 0.001), but demonstrated low accuracy (NRS 4.9), whereas SIs (P = 0.005) required more time to perform the osteotomy. The maximum temperature increase occurred in the ultrasonic group. Even though SI were the slowest, they have proved to be the most accurate (NRS 8.4) in comparison with UI (NRS 7.6) and RI (NRS 4.9). Within the limit of this study, sonic instruments could be considered a safe alternative to ultrasonic instruments.

Piezoelectric technology in otolaryngology, and head and neck surgery: a review

BACKGROUND

Piezoelectric technology has existed for many years as a surgical tool for precise removal of soft tissue and bone. The existing literature regarding its use specifically for otolaryngology, and head and neck surgery was reviewed.

METHODS

The databases Medline, the Cochrane Central Register of Controlled Trials, PubMed, Embase and Cambridge Scientific Abstracts were searched. Studies were selected and reviewed based on relevance.

RESULTS

Sixty studies were identified and examined for evidence of benefits and disadvantages of piezoelectric surgery and its application in otolaryngology. The technique was compared with traditional surgical methods, in terms of intra-operative bleeding, histology, learning curve, operative time and post-operative pain.

CONCLUSION

Piezoelectric technology has been successfully employed, particularly in otology and skull base surgery, where its specific advantages versus traditional drills include a lack of 'blunting' and tissue selectivity. Technical advantages include ease of use, a short learning curve and improved visibility. Its higher cost warrants consideration given that clinically significant improvements in operative time and morbidity have not yet been proven. Further studies may define the evolving role of piezoelectric surgery in otolaryngology, and head and neck surgery.

Morphological characteristics of osteotomies using different piezosurgical devices. A scanning electron microscopic evaluation

PURPOSE

The objective of this study was to compare morphological characteristics of osteotomies performed by 6 Piezosurgical devices.

MATERIALS AND METHODS

The 6 Piezosurgical units were: (a) Piezotom, (b) SurgySonic, (c) Piezon Master Surgery, (d) VarioSurg, (e) Surgybone, and (f) Piezosurgery 3. Osteotomies on 9 freshly slaughtered cattle ribs (2 cuts by each unit, per rib) from the cortical (first cut at 5 mm) to the cancellous (second cut at 3 mm) bone layer were performed. The osteotomy margins were compared using scanning electron microscopy analysis. The cutting areas, osteotomy bottoms, and osteotomy margins were analyzed morphologically. Statistical evaluation of the 2 cuts regarding the design of the tips (a-d: tapered tool shanks, f: parallel tool shank) was performed by an unpaired t test.

RESULTS

Morphological characteristics were different for each Piezosurgical unit and each examined area. A significant difference (P = 0.0209) of the upper width of the first cut between tapered and parallel tips was shown.

CONCLUSIONS

The morphological characteristics of the produced Piezosurgical osteotomies vary and depend on the Piezosurgical unit and tip.

The effect of piezoelectric surgery implant osteotomy on radiological and molecular parameters of peri-implant crestal bone loss: a randomized, controlled, split-mouth trial

AIM

To evaluate the effect of piezoelectric surgery (PS) implant osteotomy on biochemical and radiological parameters of crestal bone (CB) loss.

MATERIAL AND METHODS

In this randomized, controlled, clinical study, 38 osteotomies were prepared with PS and drilling in the posterior maxilla in a split-mouth design. Implants were placed and left for non-submerged healing. Osteotomy time, insertion torque, pain perception, probing depth, and modified gingival and plaque indices were recorded. Peri-implant sulcular fluid (PISF) was collected from four sites of each implant at 2, 4, 8, 12, and 24 weeks. PISF samples were analyzed by ELISA for receptor activator of nuclear factor kappa-B-ligand (RANKL) and osteoprotegerin. CB loss was assessed on periapical radiographs at the 12th and on cone beam computed tomography (CBCT) at the 24th weeks. The influence of time and osteotomy method on biochemical and radiological parameters of CB loss employed statistical method of Brunner-Langer.

RESULTS

Osteotomy time for PS group was significantly longer than the drill group (P < 0.05). Pain perception that was lower in the PS than in the drill group depended on osteotomy method (P < 0.05). PS group had lower RANKL total amount than the drill group (P < 0.05). Mean CB loss on periapical radiographs at the 12th week for PS and drill groups were 0.11 and 0.18 mm, respectively (P > 0.05). At the 24th week, PS and drill groups showed 0.11 and 0.12 mm CB losses on CBCT, respectively (P > 0.05). However, CB loss values did not depend on osteotomy modality (P > 0.05).

CONCLUSION

PS may modify and reduce bone-destructive inflammatory response during implant osseointegration. Therefore, on the molecular level, it might be a less traumatic osteotomy modality than drilling although this was not reflected by CB loss values in the present study.

Piezoelectric Bone Surgery: A Review of the Literature and Potential Applications in Veterinary Oromaxillofacial Surgery

Piezoelectric bone surgery is a recent and innovative technology, permitting a selective cut of mineralized tissue while sparing soft tissue. Similar to a dental scaler, a high frequency vibration, in the range of 25-35 kHz, is transmitted to a metallic tip. However, the power of the piezosurgical instrument is three to six times higher than that of a dental scaler. The major advantages of this technology include high precision, a design that increases ease of curvilinear osteotomy, less trauma to soft tissue, preservation of neurological and vascular structures, reduced hemorrhage, minimal thermal damage to the bone, as well as overall improvement of healing. The handpiece of the instrument is equipped with a sterile irrigation system and light-emitting diode (LED) light, which improves visibility and overall safety. Piezoelectric surgery is particularly useful when performing delicate bone procedures such as periodontal or endodontic surgery. It is also indicated when performing more invasive bone surgery such as maxillectomy, mandibulectomy, and condylectomy, where preservation of neurovascular structures is important. Piezoelectric instruments are different from rotary instrumentation or oscillating saws, they require light pressure with constant motion of the tip. Training is required to master the technique.

Escalating role of piezosurgery in dental therapeutics

Dentistry, an art in science and tranquilizer in medicine, has seen a lot of changing concepts over a decade and one such novel innovation is piezosurgery. Piezosurgery is a true revolution in bone surgery as it fulfils both biological and technical criteria. It has a variety of applications ranging from minor surgical procedures to complex implantology, plastic and reconstructive surgeries. Piezosurgery uses a low frequency modulated ultrasonic insert which produces microvibrations in the range of 60-200micro meter/sec and leads to safe and precise bony incision without damaging underlying vital structures like nerves, mucosa and vessels. It overcomes technical difficulties such as visibility by producing bloodless field during surgery and removes debris simultaneously through internal irrigation mechanism. The soft tissues remain safe and biological factors like release of certain cytokines promote bone healing and enhance patients recovery. This critical review outweighs piezosurgery over traditional tools and emphasizes on its clinical and biological aspects contributing to beneficial dental health.

Dynamics of bone healing after osteotomy with piezosurgery or conventional drilling - histomorphometrical, immunohistochemical, and molecular analysis

BACKGROUND

Piezosurgery is an osteotomy system used in medical and dental surgery. Many studies have proven clinical advantages of piezosurgery in terms of quality of cut, maneuverability, ease of use, and safety. However, few investigations have tested its superiority over the traditional osteotomy systems in terms of dynamics of bone healing. Therefore, the aim of this study was to evaluate the dynamics of bone healing after osteotomies with piezosurgery and to compare them with those associated to traditional bone drilling.

METHODS

One hundred and ten rats were divided into two groups with 55 animals each. The animals were anesthetized and the tibiae were surgically exposed to create defects 2 mm in diameter by using piezosurgery (Piezo group) and conventional drilling (Drill group). Animals were sacrificed at 3, 7, 14, 30 and 60 days post-surgery. Bone samples were collected and processed for histological, histomorphometrical, immunohistochemical, and molecular analysis. The histological analysis was performed at all time points (n = 8) whereas the histomorphometrical analysis was performed at 7, 14, 30 and 60 days post-surgery (n = 8). The immunolabeling was performed to detect Vascular Endothelial Growth Factor (VEGF), Caspase-3 (CAS-3), Osteoprotegerin (OPG), Receptor Activator of Nuclear Factor kappa-B Ligand (RANKL), and Osteocalcin (OC) at 3, 7, and 14 days (n = 3). For the molecular analysis, animals were sacrificed at 3, 7 and 14 days, total RNA was collected, and quantification of the expression of 21 genes related to BMP signaling, Wnt signaling, inflammation, osteogenenic and apoptotic pathways was performed by qRT-PCR (n = 5).

RESULTS

Histologically and histomorphometrically, bone healing was similar in both groups with the exception of a slightly higher amount of newly formed bone observed at 30 days after piezosurgery (p < 0.05). Immunohistochemical and qRT-PCR analyses didn't detect significant differences in expression of all the proteins and most of the genes tested.

CONCLUSIONS

Based on the results of our study we conclude that in a rat tibial bone defect model the bone healing dynamics after piezosurgery are comparable to those observed with conventional drilling.

Intraoperative complications during sinus floor elevation using two different ultrasonic approaches: a two-center, randomized, controlled clinical trial

PURPOSE

The aim of this study was to assess the prevalence of intraoperative complications during maxillary sinus elevation with lateral approach using a piezoelectric device with two different surgical techniques.

MATERIALS AND METHODS

Antrostomies were randomly performed by outlining a window (group A, 36 patients) or by eroding the cortical wall with a grinding insert until the membrane was visible under a thin layer of bone, before outlining the window (group B, 36 patients). Occurrence of membrane perforation, laceration of vascular branches, and surgical time was recorded.

RESULTS

Seventy-two patients underwent sinus floor elevation: four perforations (11.1%) were observed in group A (two occurred during elevation with hand instruments) and zero perforations in group B (p < .05). No evidence of vascular lacerations was registered in both groups. A clinically insignificant but statistically shorter surgical time was recorded in group A (9.2 ± 3.7 minutes) than in group B (13.3 ± 2.4 minutes; p < .05).

CONCLUSIONS

Within the limits of the present study, it may be concluded that ultrasonic erosion of the lateral wall of the sinus is a more predictable technique than piezoelectric outlining of a bone window in preventing from accidental perforations of Schneiderian membrane during sinus augmentation procedures.