Piezoelectric vs. conventional implant site preparation: ex vivo implant primary stability

Primary Stability of Implants Inserted into Polyurethane Blocks: Micro-CT and Analysis In Vitro

The approach employed for the site preparation of the dental implant is a variable factor that affects the implant's primary stability and its ability to integrate with the surrounding bone. The main objective of this in vitro study is to evaluate the influence of different techniques used to prepare the implant site on the primary stability of the implant in two different densities of artificial bone.

MATERIALS AND METHODS

A total of 150 implant sites were prepared in rigid polyurethane blocks to simulate two distinct bone densities of 15 pounds per cubic foot (PCF) and 30 PCF, with a 1-mm-thick simulated cortex. The implant sites were equally distributed among piezoelectric surgery (PES), traditional drills (TD), and black ruby magnetic mallet inserts (MM). Two methods have been employed to evaluate the implant's primary stability, Osstell and micro-tomography.

RESULTS

In the present study, we observed significant variations in the implant stability quotient (ISQ) values. More precisely, our findings indicate that the ISQ values were generally higher for 30 PCF compared to 15 PCF. In terms of the preparation technique, PES exhibited the greatest ISQ values, followed by MM, and finally TD. These findings corresponded for both bone densities of 30 PCF (PES 75.6 ± 1.73, MM 69.8 ± 1.91, and TD 65.8 ± 1.91) and 15 PCF (PES 72.3 ± 1.63, MM 62.4 ± 1.77, and TD 60.6 ± 1.81). By utilizing Micro-CT scans, we were able to determine the ratio of the implant occupation to the preparation site. Furthermore, we could calculate the maximum distance between the implant and the wall of the preparation site. The findings demonstrated that PES had a higher ratio of implant to preparation site occupation, followed by TD, and then the MM, at a bone density of 30 PCF (PES 96 ± 1.95, TD 94 ± 1.88, and MM 90.3 ± 2.11). Nevertheless, there were no statistically significant differences in the occupation ratio among these three approaches in the bone density of 15 PCF (PES 89.6 ± 1.22, TD 90 ± 1.31, and MM 88.4 ± 1.17). Regarding the maximum gap between the implant and the site preparation, the smallest gaps were seen when TD were used, followed by MM, and finally by PES, either in a bone density 15 PCF (PES 318 ± 21, TD 238 ± 17, and MM 301 ± 20 μm) or in a bone density 30 PCF (PES 299 ± 20, TD 221 ± 16, and MM 281 ± 19 μm). A statistical analysis using ANOVA revealed these differences to be significant, with p-values of < 0.05.

CONCLUSION

The outcomes of this study indicate that employing the PES technique and osteo-densification with MM during implant insertion may enhance the primary stability and increase the possibility of early implant loading.

Evaluation of implant site preparation with piezosurgery versus conventional drills in terms of operation time, implant stability and bone density (randomized controlled clinical trial- split mouth design)

BACKGROUND

The preparation of the implant bed has a major influence on the success rate and long-term survival of dental implants. Piezoelectric devices and special implant drilling inserts are now emerging to replace conventional drills showing improved bone response and healing around implants. The purpose of this study is to compare the piezoelectric inserts versus the traditional drills for implant site preparation.

METHODS

Twelve male patients who received a total of twenty-four dental implants have been selected to participate in this split-mouth clinical trial. Each patient received two implants; one installed after piezosurgery assisted osteotomy, while the contralateral side received the implant with the original drilling protocol. The timing of surgery, implant stability, and bone density around the installed dental implants have been evaluated during a follow-up period extended to 4 months.

RESULTS

a significant difference in terms of time of surgery (p < 0.005) and in implant stability at 4 months (p = 0.024) on the study side, while a non-statistical significance in terms of bone density was detected (p = 0.468).

CONCLUSION

The piezoelectric implant site drilling protocol seemed to be a reliable and repeatable technique. Despite the limited sample size and lengthier operative time, the piezoelectric inserts enhanced bone quality and implant stability. Clinical trial registration Current Controlled Trials (ClinicalTrials.gov) https://clinicaltrials.gov/ct2/show/NCT05512273 ; the date of registration: 23/08/2022. Retrospectively registered.

Primary Stability of Short Implants Inserted Using Piezoelectric or Drilling Systems: An In Vitro Comparison

The primary objective of the present in vitro study was to evaluate the influence of implant site preparation technique (drills vs ultrasonic instrumentation) on the primary stability of short dental implants with two different designs inserted in simulated low-quality cancellous bone. Eighty implant sites were prepared in custom-made solid rigid polyurethane blocks with two different low cancellous bone densities (5 or 15 pounds per cubic foot [PCF]), equally distributed between piezoelectric (Surgysonic Moto, Esacrom, Italy) and conventional drilling techniques. Two short implant systems (Prama and Syra, Sweden & Martina) were tested by inserting 40 fixtures of each system (both 6.0 mm length and 5.0 mm diameter), divided in the four subgroups (drills/5 PCF density; drills/15 PCF density; piezo/5 PCF density; piezo/15 PCF density). Insertion torque (Ncm), implant stability quotient values, removal torque (Ncm), and surgical time were recorded. Data were analyzed by 3-way ANOVA and Scheffé's test (α = 0.05). With slight variations among the considered dependent variables, overall high primary implant stability was observed across all subgroups. Piezoelectric instrumentation allowed for comparable or slightly superior primary stability in comparison with the drilling procedures in both implant systems. The Prama implants group showed the highest mean reverse torque and Syra implants the highest implant stability quotient values. Piezoelectric implant site preparation took prolonged operative time compared to conventional preparation with drills; among the drilling procedures, Syra system required fewer surgical steps and shorter operative time.

Observational Study on the Preparation of the Implant Site with Piezosurgery vs. Drill: Comparison between the Two Methods in terms of Postoperative Pain, Surgical Times, and Operational Advantages

Purpose

Recent advances show that ultrasonic implant site osteotomy is related to a decreased trauma and a better postoperative healing of the surgical site when compared to traditional drilling techniques. The micrometric bone cutting control and the operative advantages related to the piezoelectric approach are also characterized by a learning curve for the clinician in surgical practice and an increased operative duration of the procedure. The aim of this investigation is to compare the operative time, the postoperative pain, and the amount of painkillers taken by the patient during the healing period.

Methods

A total of 65 patients were treated at the Unit of Oral Surgery (Department of Medical Sciences, Surgery and Health, University of Trieste, Italy) using a split mouth model: 75 drill-inserted implants (G1) and 75 piezoelectric device-inserted implants (G2) were placed. The Visual Analogue Scale (VAS) was performed to evaluate the postoperative pain at 15 days from surgery. The operative time and frequency of intake of painkillers were measured.

Results

The G1 and G2 groups showed a significant difference with a higher use of painkillers observed for G1. The G2 patients showed a lower level of pain (VAS) at all experimental times between 8 hours to 7 days (p < 0.01) postsurgery. At 15 days, the pain levels were similar for both groups. No differences were found in site preparation duration between the study groups.

Conclusions

The evidence supports the application of the piezoelectric approach compared to the drill's osteotomy as a useful technique for implant site preparation. This trial is registered with NCT03978923.

Heat Generation at the Implant-Bone Interface by Insertion of Ceramic and Titanium Implants

PURPOSE

The aim of this study is to record material- and surface-dependent heat dissipation during the process of inserting implants into native animal bone.

MATERIALS AND METHODS

Implants made of titanium and zirconium that were identical in macrodesign were inserted under controlled conditions into a bovine rib tempered to 37 °C. The resulting surface temperature was measured on two bone windows by an infrared camera. The results of the six experimental groups, ceramic machined (1), sandblasted (2), and sandblasted and acid-etched surfaces (3) versus titanium implants with the corresponding surfaces (4, 5, and 6) were statistically tested.

RESULTS

The average temperature increase, 3 mm subcrestally at ceramic implants, differed with high statistical significance (p = 7.163 × 10^-9, resulting from group-adjusted linear mixed-effects model) from titanium. The surface texture of ceramic implants shows a statistical difference between group 3 (15.44 ± 3.63 °C) and group 1 (19.94 ± 3.28 °C) or group 2 (19.39 ± 5.73 °C) surfaces. Within the titanium implants, the temperature changes were similar for all surfaces.

CONCLUSION

Within the limits of an in vitro study, the high temperature rises at ceramic versus titanium implants should be limited by a very slow insertion velocity.

Does the Drilling Technique for Implant Site Preparation Enhance Implant Success in Low-Density Bone? A Systematic Review

PURPOSE

The objective of this systematic review was to investigate the possible association between the drilling technique and proper implant integration and survival in areas with low bone density.

MATERIALS AND METHODS

An electronic search using the MEDLINE/PubMed database was performed including studies published up to April 2018. Animal and clinical studies that evaluated the association between the drilling technique and proper implant integration and survival in low-density bone were included.

RESULTS

Fifteen studies met the inclusion criteria, including 7 experimental and 8 clinical. Undersized, osteotome, Piezosurgery, and osseodensification drilling were the 4 techniques found in the literature to enhance osseointegration of implants in low-density bone. Owing to the methodological variation, meta-analysis was not performed. The 4 drilling protocols were effective in increasing primary stability, but the long-term outcome is comparable with that of the conventional surgical drilling protocol.

CONCLUSION

There is weak evidence suggesting that any of the previously mentioned surgical techniques could enhance successful osseointegration and survival of the implants placed in low-density bone.

Immediate Loading of Implant-Supported Single Crowns after Conventional and Ultrasonic Implant Site Preparation: A Multicenter Randomized Controlled Clinical Trial

Aim

To compare implant survival rate and marginal bone loss (MBL) of immediately loaded single implants inserted by using ultrasonic implant site preparation (UISP) (test) and conventional rotary instrumentation (control).

Methods

Two single implants were inserted for each patient: after randomization, test site was prepared by using an ultrasonic device (Piezosurgery Touch, Mectron, Italy) and control site was prepared by using the drills of the selected implant system (Premium AZT, Sweden & Martina, Italy), until reaching a final diameter of 3 mm in both groups. Identical implants (3.8x11.5 mm) were inserted in all sites at crestal level. Impressions were taken and screwed resin single crowns with platform-switched provisional abutments were delivered with 48 hours. Periapical radiographs were taken at provisional crown insertion (T0), 6 months (T1) and one year (T2) after prosthetic loading to measure MBL. All data were tested for normality and subsequently analyzed by paired samples t-test and forward multiple linear regression.

Results

Forty-eight patients were treated in six centers with the insertion of ninety-six implants (48 test; 48 control). Four implants in four patients failed within the first six months of healing (two in test group; two in control group; no difference between groups). Forty patients (age 60.1±10.7 years; 22 female, 18 male) were included in the final analysis. Mean MBL after six months of loading was 1.39±1.03 mm in the test group and 1.42±1.16 mm in the control group (p>0.05) and after one year was 1.92±1.14 mm and 2.14±1.55 mm in test and control, respectively (p>0.05).

Conclusions

No differences in survival rate and MBL were demonstrated between UISP and conventional site preparation with rotary instruments in immediately loaded dental implants: UISP, with its characteristics of enhanced surgical control and safety in proximity of delicate structures, may be used as a reliable alternative to the traditional drilling systems.

Piezoelectric versus conventional implant site preparation: A systematic review and meta-analysis

BACKGROUND

The use of a piezoelectric device (PED) for implant site preparation (ISP) has been introduced to overcome the limitations of using conventional drills (CDs). With little and inconsistent information in the literature regarding their efficiency for preparing implant osteotomies, the objective of this systematic review was to compare the use of CDs to PEDs for ISP with regard to implant stability values, marginal bone level changes, operating time, and dental implant failure rate.

METHODS

The systematic review was prepared according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The literature was searched for studies that assessed the use of CDs and PEDs for ISP. The Cochrane Collaboration risk of bias tool was used to evaluate the selected studies and meta-analyses were performed using statistical software.

RESULTS

A total of 755 citations were identified. Of these, 4 studies with 178 implant osteotomies in 80 participants were included. The pooled estimates for the implant stability showed significant differences between the 2 surgical techniques in favor of PEDs at baseline, 8 and 12 weeks. A statistically significant difference in the operating time was also shown between the 2 techniques with more time required using PED. The differences in marginal bone level changes or implant failure rate were not statistically significant.

CONCLUSIONS

With the limitations of this review in mind, PEDs appear to be a viable alternative to traditional drilling techniques for ISP. With the exception of prolonged operating time associated with the use of PEDs, both techniques were comparable in terms of the marginal bone level changes and the risk of implant failure. The favorable influence of the implant stability pattern related to the use of PEDs on the predictability of immediate and early loading protocols need to be confirmed in future studies.

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.

The effect of 2 versus 4 implants on implant stability in mandibular overdentures: A randomized controlled trial

STATEMENT OF PROBLEM

Dental research is rich with articles that investigated the influence of host-site variables, some implant-related variables (implant length, diameter, taper, design, location, and surface topography), different loading protocols or surgical procedures, and measurement methodology on dental implant stability. However, the number of implants and its effect on implant stability remain unclear.

PURPOSE

The purpose of this randomized clinical trial was to investigate the influence of implant number on implant stability by comparing 2 versus 4 implants in mandibular implant overdentures.

MATERIAL AND METHODS

The trial included 20 participants with edentulous mandibular ridges. Participants were randomly assigned to 2 equal groups, a 4-implant (experimental) group consisting of 4 implants installed in lateral-canine and premolar regions; and a 2-implant (control) group, consisting of 2 implants in lateral-canine regions. Implant stability was measured using resonance frequency analysis at implant placement and then at 1, 3, 6, 9, and 12 months. The Student t test was used to compare the implant stability quotient (ISQ) values of the anterior implants in the 4-implant and 2-implant groups. One-way ANOVA followed by the post hoc Bonferroni test was used to compare ISQ values among the different follow-up periods within each group (α=.05).

RESULTS

Mean ISQ values for anterior implants in the 4-implant group were slightly higher than those recorded for the 2-implant group at all follow-up periods. However, these differences were not statistically significant (P>.05). Within-group comparison revealed an initial decrease in implant stability for all implants. This decrease was statistically significant for the 2-implant group (P<.001) and for posterior implants in the 4-implant group (P<.001). This was then followed by a gradual increase in ISQ values for all implants in both groups.

CONCLUSIONS

Increasing the number of implants from 2 to 4 in mandibular implant overdentures did not have a significant influence on implant stability.

Influence of Piezosurgery on Bone Healing around Titanium Implants: A Histological Study in Rats

The aim of this study was to evaluate histomorphometrically the influence of two techniques of dental implant site preparation on bone healing around titanium implants. Fifteen male Wistar rats (±300 g) were used in the study. Each tibia was randomly assigned to receive the implant site preparation either with a conventional drilling technique (control - DRILL group) or with a piezoelectric device (PIEZO group). The animals were sacrificed after 30 days and then the following histomorphometric parameters were evaluated (percentage) separately for cortical and cancellous regions: proportion of mineralized tissue (PMT) adjacent to implant threads (500 μm adjacent); bone area within the threads (BA) and bone-implant contact (BIC). The results demonstrated that there were no statistically significant differences between both groups for cancellous BIC (p>0.05) and cortical PMT (p>0.05). On the other hand, a higher percentage of BA was observed in the PIEZO group in the cortical (71.50±6.91 and 78.28±4.38 for DRILL and PIEZO groups, respectively; p<0.05) and cancellous regions (9.62±4.06 and 19.94±14.18 for DRILL and PIEZO groups, respectively; p<0.05). The piezosurgery also showed higher PMT values in the cancellous zone (9.35±5.54 and 18.72±13.21 for DRILL and PIEZO groups, respectively; p<0.05). However, the DRILL group presented better results for BIC in cortical region (80.42±10.88 and 70.25±16.93 for DRILL and PIEZO groups, respectively; p<0.05). In conclusion, for the implant site preparation, the piezosurgery was beneficial to bone healing rates in the cancellous bone region, while the drill technique produced better results in the cortical bone.

Biomechanical evaluation of oversized drilling technique on primary implant stability measured by insertion torque and resonance frequency analysis

Background

This study evaluated the influence of implant site preparation depth on primary stability measured by insertion torque and resonance frequency analysis (RFA).

Material and Methods

Thirty-two implant sites were prepared in eight veal rib blocks. Sixteen sites were prepared using the conventional drilling sequence recommended by the manufacturer to a working depth of 10mm. The remaining 16 sites were prepared using an oversize drilling technique (overpreparation) to a working depth of 12mm. Bone density was determined using cone beam computerized tomography (CBCT). The implants were placed and primary stability was measured by two methods: insertion torque (Ncm), and RFA (implant stability quotient [ISQ]).

Results

The highest torque values were achieved by the conventional drilling technique (10mm). The ANOVA test confirmed that there was a significant correlation between torque and drilling depth (p<0.05). However, no statistically significant differences were obtained between ISQ values at 10 or 12 mm drilling depths (p>0.05) at either measurement direction (cortical and medullar). No statistical relation between torque and ISQ values was identified, or between bone density and primary stability (p >0.05).

Conclusions

Vertical overpreparation of the implant bed will obtain lower insertion torque values, but does not produce statistically significant differences in ISQ values.

Key words:Implant stability quotient, overdrilling, primary stability, resonance frequency analysis, torque.

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.

Cell viability after osteotomy and bone harvesting: comparison of piezoelectric surgery and conventional bur

The aim of this study was to evaluate and compare the influence of a piezoelectric device versus a conventional bur on osteocyte viability and osteoblast and osteoclast activity using an in vivo mouse model. Osteotomies were created and bone grafts were harvested using either a conventional bur or a piezoelectric device; the resulting injuries and bone grafts were evaluated over an extended time-course using molecular and cellular assays for cell death (TUNEL assay), cell viability (4',6-diamidino-2-phenylindole (DAPI) staining), the onset of mineralization (alkaline phosphatase activity), and bone remodelling (tartrate-resistant acid phosphatase activity). Osteotomies created with a piezoelectric device showed greater osteocyte viability and reduced cell death. Bone grafts harvested with a piezoelectric device exhibited greater short-term cell viability than those harvested with a bur, and exhibited slightly more new bone deposition and bone remodelling. The difference in response of osteocytes, osteoblasts, and osteoclasts to bone cutting via a bur and via a piezoelectric device is negligible in vivo. Given the improved visibility and the margin of safety afforded by a piezoelectric device, they are the instrument of choice when cutting or harvesting bone to preserve soft tissue.

Primary stability comparison using piezoelectric or conventional implant site preparation systems in cancellous bone: a pilot study

PURPOSE

This study compares implant primary stability achieved in cancellous bone after placement in piezoelectric prepared sites versus conventionally drilled sites.

MATERIALS AND METHODS

Four bovine ribs were randomly assigned and placed in a water bath at 36.5 °C. Five sites per rib (total n = 20 sites) were prepared using piezoelectric system (test) or conventional drills (control) with twenty 10 × 3.6-mm Implantium implants placed. Using Osstell Mentor quantitative analysis, 5 resonance frequency analysis [implant stability quotient {ISQ}] values per implant were recorded at 5 locations for a total of 100 measurements.

RESULTS

Independent t test analysis indicated significant difference in primary stabilities between groups: t (17) = 2.637, P = 0.17, with equal variance assumption satisfied (P = 0.196). Examination of means indicated a higher mean ISQ for piezoelectric than for conventional: 58.9 (+8.55) versus 49.2 (+7.33), respectively. Analysis of variance indicated a significant difference in mean ISQ value by rib. Tukey test indicated significantly higher ISQ values for rib A (test) than ribs B, C (control), and D (test).

CONCLUSION

Implant site preparation using the piezoelectric system gives higher implant primary stability in cancellous bone. However, variations in quality across bones may have affected the results.