Bone loss after ridge expansion with or without reflection of the periosteum

Osseodensification: An Innovative Technique With Manifold Gains

Prosthodontics, which is removable and fixed, is the branch dealing with the replacement of missing teeth. Implant therapy is the popular treatment modality and commonly preferred treatment option by many patients and clinicians for missing teeth in recent years. Primary implant stability (PIS) is one of the crucial factors for osseointegration. It has been considered a crucial factor in the success of implants. Moreover, several factors influence PIS. On the other hand, both secondary implant stability and osseointegration are influenced by the PIS. Bone density, bone volume, bone-to-implant contact, and other factors that enhance or degrade the primary stability. Certain host sites such as the maxillary posterior region demand more dense bone to achieve desired results as they are the low-density areas of the jaw. So, a new promising and growing innovative concept of osseodensification (OD) offers a great solution with multiple benefits and desirable results. This review article aims to enlighten the multiple benefits of OD technique and their mechanism of action.

Alveolar ridge splitting and simvastatin loaded xenograft for guided bone regeneration and simultaneous implant placement: randomized controlled clinical trial

OBJECTIVES

The present study goal was to assess clinically and radiographically using simvastatin (SMV) loaded xenograft for guided bone regeneration (GBR) around simultaneously placed implants with alveolar ridge splitting in patients with horizontally atrophic jaw defect.

MATERIALS AND METHODS

Randomized distribution of the twenty-two patients into two groups (11 patients each) was performed. Group I participants received alveolar ride splitting (ARS) with GBR using SMV gel mixed bone graft and a barrier membrane with simultaneous implant placement. Group II received the same treatment protocol without SMV gel. At the baseline, 6- and 9-months post-surgery, clinical and radiological alterations were assessed.

RESULTS

Six months after therapy, PES records of group I were statistically significantly improved than those of group II (P < .001). Group I exhibited statistically significant expansion of the alveolar ridge over group II after 6 and 9 months (P < .001). When compared to group II over the evaluation interval between 6 and 9 months, group I demonstrated statistically substantially minimal loss of the mean marginal bone level (P < .001). At the 6- and 9-month observation periods, bone density gain was considerably higher in group I than that in group II (P < .001).

CONCLUSION

Alveolar ridge splitting along with GBR-augmented SMV improve the clinical and radiographical outcomes around dental implant over GBR alone.

CLINICAL RELEVANCE

Augmenting GBR with SMV in alveolar ridge splitting could boost implant osseointegration and enhance peri-implant tissue changes.

CLINICAL TRIAL REGISTRATION

NCT05020405.

Bone Graft Packing and Its Association with Bone Regeneration in Maxillary Sinus Floor Augmentations: Histomorphometric Analysis of Human Biopsies

Research in maxillary sinus floor augmentation (MSFA) focussed on the optimisation of microstructural parameters such as microporosity and particle size of bone substitute particles (BS). However, little is known about the impact of BS packing and the corresponding (void) interparticular space on bone regeneration. The aim of this study was to characterise the spatial distribution of BS and its association with BS integration 6 ± 1 months after MSFA. Histological thin-ground sections of 70 human sinus biopsies were histomorphometrically analysed: In serial zones of 100 µm proceeding from the sinus floor (SF) up to the apical end of the biopsy, we measured the distribution of BS particles within these zones in terms of volume (BSV/TV), number and size of BS particles, interparticle spacing (BS.Sp) and bone-to-BS contact. BS particles were not homogeneously distributed over the length of biopsies: The first 200 µm directly adjacent to the SF represented a zone poor in BS particles but with high osteogenic potential. Graft packing density increased from the SF towards the apical part of the AA. Integration of BS particles was inversely associated with the distance to the SF and the graft packing density. A high packing density through excessive compaction of BS particles should be avoided to optimise the macrostructural environment for bone regeneration.

Biological mechanisms underlying complications related to implant site preparation

Implant site preparation is a critical stage of implant surgery that may underpin various complications related to implant surgery. This review discusses the latest available scientific information on risk factors related to implant site preparation. The role of the drilling process in relation to the density of the available alveolar bone, the effects of insertion torque on peri-implant osseous healing, and implant-related variables such as macrodesign and implant-abutment connection are all factors that can influence implant success. Novel information that links osteotomy characteristics (including methods to improve implant initial stability, the impact of drilling speed, and increase of the implant insertion torque modifying the bone-implant interface) with the appropriate instrumentation techniques will be discussed, as well as interactions at the bone-biomaterial interface that may lead to biologic complications mediated by implant dissolution products.

Bilateral Bone Ridge Splitting in Maxilla with Immediate Implant Placement in a Patient with Osteoporosis: A Clinical Report with 2-Year Follow-up

Every year, a higher percentage of bisphosphonates is prescribed for osteoporosis treatment which can lead to bone osteonecrosis after several surgical procedures in the oral cavity. This report describes an approach to restore two missing teeth, employing bilateral bone ridge splitting in the maxilla with immediate placement of implants in a patient using bisphosphonates in the management of osteoporosis. Two titanium implants with a width of 3.45 mm and a length of 10 mm were placed in the maxillary ridge with a diameter of 4.4 mm and 3.0 mm in positions 15 and 24 according to the classification of the World Dental Federation. The implants were placed immediately by bone splitting, using a piezosurgery device and guided bone regeneration with an alloplastic material and a collagen membrane. Five months later, the implants were uncovered and the final porcelain crowns were cemented. 24 months later, the control through clinical and radiographical examinations showed no bone loss in the collar part of the implants and the proper status of the peri-implant soft tissue without any signs of inflammation. Piezosurgery is a useful and safe method of ridge splitting in a very thin ridge (4.5 and 3.0 mm).

Use of a Non-Crosslinked Collagen Membrane During Guided Bone Regeneration Does Not Interfere With the Bone Regenerative Capacity of the Periosteum

PURPOSE

To assess whether the use of a non-crosslinked porcine collagen type I and III bi-layered membrane inter-positioned between the periosteum and a bone defect would interfere with the bone regenerative capacity of the periosteum.

MATERIALS AND METHODS

Sixty rats, each with 1 critical-size calvarial defect (CSD; diameter, 5 mm) in the parietal bone, were randomly allocated to 1 of 3 equal-size groups after CSD creation: 1) the periosteum was excised and the flap was repositioned without interposition of a membrane (no-periosteum [NP] group); 2) the flap including the periosteum was repositioned (periosteum [P] group); and 3) a non-crosslinked collagen membrane was inter-positioned between the flap, including the periosteum, and the bone defect (membrane [M] group). Micro-computed tomography, qualitative histology, immunohistochemistry, and reverse transcription real-time quantitative polymerase chain reaction were performed at 3, 7, 15, and 30 days postoperatively.

RESULTS

A markedly increased radiographic residual defect length was observed in the NP group compared with the P group at 30 days. The NP group also presented a smaller radiographic bone fill area than the P group at 15 and 30 days and then the M group at 30 days. The P and M groups exhibited considerably greater expression of bone morphogenetic protein-2 and osteocalcin than the NP group at 7 days; expression of transforming growth factor-β1 was considerably greater in the NP group at 15 days. Further, the P group presented considerably higher gene expression levels of Runx2 and Jagged1 at 7 days and of alkaline phosphatase at 3 and 15 days compared with the M and NP groups.

CONCLUSION

Interposition of this specific non-crosslinked collagen membrane between the periosteum and the bone defect during guided bone regeneration interferes only slightly, if at all, with the bone regenerative capacity of the periosteum.

Finite Element Analysis and Biomechanical Testing to Analyze Fracture Displacement of Alveolar Ridge Splitting

The alveolar ridge splitting technique enables reconstruction of atrophied alveolar ridges prior implantation. However, in cases of severe atrophy, there is an unpredictable risk of fracturing the buccal lamella during the expansion. Currently, there is no preoperative assessment to predict the maximum distraction of the lamella. The aim of this study was to develop a biomechanical model to mimic the alveolar ridge splitting and a finite element (FE) model to predict the experimental results. The biomechanical testing was conducted on porcine mandibles. To build the FE model high resolution peripheral quantitative computer tomography scans of one specimen was performed after the osteotomy outline, but before the lamella displacement. A servo-electric testing machine was used for the axial tension test to split the lamellae. Results showed, in line with clinical observations, that the lamellae broke primarily at the base of the splits with a median displacement of 1.27 mm. The FE model could predict fracture force and fracture displacement. Fracture force showed a nonlinear correlation with the height of the bone lamella. In conclusion, good correspondence between mechanical testing and virtual FE analysis showed a clinically relevant approach that may help to predict maximum lamella displacement to prevent fractures in the future.

New Osseodensification Implant Site Preparation Method to Increase Bone Density in Low-Density Bone: In Vivo Evaluation in Sheep

PURPOSE

The aim of this study was to evaluate a new surgical technique for implant site preparation that could allow to enhance bone density, ridge width, and implant secondary stability.

MATERIALS AND METHODS

The edges of the iliac crests of 2 sheep were exposed and ten 3.8 × 10-mm Dynamix implants (Cortex) were inserted in the left sides using the conventional drilling method (control group). Ten 5 × 10-mm Dynamix implants (Cortex) were inserted in the right sides (test group) using the osseodensification procedure (Versah). After 2 months of healing, the sheep were killed, and biomechanical and histological examinations were performed.

RESULTS

No implant failures were observed after 2 months of healing. A significant increase of ridge width and bone volume percentage (%BV) (approximately 30% higher) was detected in the test group. Significantly better removal torque values and micromotion under lateral forces (value of actual micromotion) were recorded for the test group in respect with the control group.

CONCLUSION

Osseodensification technique used in the present in vivo study was demonstrated to be able to increase the %BV around dental implants inserted in low-density bone in respect to conventional implant drilling techniques, which may play a role in enhancing implant stability and reduce micromotion.

Assessment of Temperature Rise and Time of Alveolar Ridge Splitting by Means of Er:YAG Laser, Piezosurgery, and Surgical Saw: An Ex Vivo Study

The most common adverse effect after bone cutting is a thermal damage. The aim of our study was to evaluate the bone temperature rise during an alveolar ridge splitting, rating the time needed to perform this procedure and the time to raise the temperature of a bone by 10°C, as well as to evaluate the bone carbonization occurrence. The research included 60 mandibles (n = 60) of adult pigs, divided into 4 groups (n = 15). Two vertical and one horizontal cut have been done in an alveolar ridge using Er:YAG laser with set power of 200 mJ (G1), 400 mJ (G2), piezosurgery unit (G3), and a saw (G4). The temperature was measured by K-type thermocouple. The highest temperature gradient was noted for piezosurgery on the buccal and lingual side of mandible. The temperature rises on the bone surface along with the increase of laser power. The lower time needed to perform ridge splitting was measured for a saw, piezosurgery, and Er:YAG laser with power of 400 mJ and 200 mJ, respectively. The temperature rise measured on the bone over 10°C and bone carbonization occurrence was not reported in all study groups. Piezosurgery, Er:YAG laser (200 mJ and 400 mJ), and surgical saw are useful and safe tools in ridge splitting surgery.

Biomechanical comparison of a novel engine-driven ridge spreader and conventional ridge splitting techniques

OBJECTIVES

Ridge splitting techniques are used for horizontal ridge augmentation in implant dentistry. Recently, a novel engine-driven ridge splitting technique was introduced. This study compared the mechanical forces produced by conventional and engine-driven ridge splitting techniques in porcine mandibles.

MATERIAL AND METHODS

In 33 pigs, mandibular premolar areas were selected for the ridge splitting procedures, designed as a randomized split-mouth study. The conventional group underwent a chisel-and-mallet procedure (control group, n = 20), and percussive impulse (Newton second, Ns) was measured using a sensor attached to the mallet. In the engine-driven ridge spreader group (test group, n = 23), a load cell was used to measure torque values (Newton centimeter, Ncm). Horizontal acceleration generated during procedures (control group, n = 10 and test group, n = 10) was compared between the groups.

RESULTS

After ridge splitting, the alveolar crest width was significantly increased both in the control (1.23 ± 0.45 mm) and test (0.98 ± 0.41 mm) groups with no significant differences between the groups. The average impulse of the control group was 4.74 ± 1.05 Ns. Torque generated by rotation in the test group was 9.07 ± 2.15 Ncm. Horizontal acceleration was significantly less in the test group (0.82 ± 1.05 g) than the control group (64.07 ± 42.62 g) (P < 0.001).

CONCLUSIONS

Narrow edentulous ridges can be expanded by novel engine-driven ridge spreaders. Within the limits of this study, the results suggested that an engine-driven ridge splitting technique may be less traumatic and less invasive than a conventional ridge splitting technique.