Lateral Augmentation Research Articles

Lateral ridge augmentation with two different ratios of deproteinized bovine bone and autogenous bone: A 2-year follow-up of a randomized and controlled trial.

The optimal ratio of deproteinized bovine bone (DPBB) and autogenous bone (AB) for lateral augmentation is presently unknown. To evaluate implant treatment outcome and radiological graft changes after lateral ridge augmentation with 2 different mixtures of DPBB and AB, 2 years after functional loading. Thirteen patients were included in a split mouth, randomized, controlled trial. Four partially edentulous and 10 totally edentulous jaws with an alveolar ridge width of <4 mm were augmented with a graft mixture of 90:10 (DPBB:AB) on one side and 60:40 (DPBB:AB) on the contra lateral side. Graft width changes were measured on CBCT scans at different time points. Implant survival and success rates were calculated. Resonance frequency analysis and marginal bone measurements were performed after 2 years of loading. The survival rate was 94.4% for implants installed in the 90:10 and 100% for implants installed in the 60:40. There were no statistically significant differences in survival rate or success rate between the mixtures. The width was 5.7 mm and 6.2 mm, respectively for the 2 groups without any significant difference between the groups after 2 years of loading. There was a significant difference in graft reduction between the groups, 54.4% (90:10) and 37.5% (60:40), respectively. There were no statistically significant differences in implant stability or marginal bone levels at any time points. The 2 treatment modalities may be successfully used for lateral ridge augmentation and presented good clinical results after 2 years of loading. However, long-term RCTs are required before final conclusions can be provided on this specific topic.

Histomorphometric and immunohistochemical evaluation of collagen containing xenogeneic bone blocks used for lateral bone augmentation in staged implant placement

BackgroundThe osteoconductive properties of collagen containing xenogeneic bone blocks (CCXBB) remain unclear. The aim of this prospective single-arm clinical study was to assess the histological outcomes of CCXBB blocks used as bone replacement grafts for lateral bone augmentation procedures.MethodsIn 15 patients with severe horizontal alveolar ridge resorption, lateral augmentation procedures were performed using CCXBB as bone replacement grafts. Twenty-six weeks postoperatively, a re-entry procedure was performed to evaluate the bone width for adequate implant placement and two histological specimens were retrieved from each patient, one being processed for ground sectioning and the other for decalcified paraffin-included sections. In non-decalcified sections, the relative proportions occupied by bone, biomaterials, and connective tissue present in the biopsies were identified. In de-calcified sections, structures and cells positive for osteopontin (OPN), tartrate-resistant acid phosphatase activity (TRAP), osteocalcin (OSC), and alkaline phosphatase (ALP) were assessed.ResultsSoft tissue dehiscence occurred during the follow-up in 5 out of 15 patients (33.3%). The mean crest width at baseline was 2.78 mm (SD 0.57) and the mean crest width at re-entry was 6.90 mm (SD 1.22), with a mean ridge width increase of 4.12 mm (SD 1.32). Twenty-six bone biopsies were obtained from 13 patients. Histomorphometric analysis showed a mean of 26.90% (SD 12.21) of mineralized vital bone (MVB), 21.37% (SD 7.36) of residual CCXBB, 47.13% (SD 19.15) of non-mineralized tissue, and 0.92% of DBBM. The immunohistochemical analysis revealed a large number of OPN-positive cells 8.12% (SD 4.73), a lower proportion of TRAP positive multinuclear cells 5.09% (SD 4.91), OSC-positive cells 4.09% (SD 4.34), and a limited amount of ALP positive cells 1.63% (SD 2).ConclusionsCCXBB achieved significant horizontal crestal width allowing for staged implant placement in most of the patients. In light of the histological outcomes and implant failures, special attention must be placed to prevent soft tissue dehiscence when CCXBB is used in severe atrophic alveolar crests.

Alveolar Ridge Augmentation Using Dystopic Autogenous Tooth: 2-Year Results of an Open Prospective Study.

To evaluate the use of chemically unchanged tooth material in lateral alveolar ridge augmentation or for the filling of jaw defects. A total of 20 patients underwent either lateral augmentation of the alveolar process (11 patients) or filling of jaw defects (6 patients) with autogenous unaltered tooth material in a longitudinal 2-year study. In three patients, the jaw defect was so marked that a bone block graft had to be used for augmentation in addition to particulate dental material. In four patients, an autogenous tooth block was exclusively used; in seven, crushed tooth material was exclusively used; and in the remaining six, dystopic teeth that had been extracted were removed, crushed, and reinserted into the defect in particulate form. Fully impacted teeth served as autogenous donor teeth. After a healing time of 3 to 6 months, 28 implants could be placed (10 immediate implants, 18 delayed implants). At 6, 12, and 24 months postrestoration, peri-implant bone loss as assessed by x-ray was 0 mm, 0.4 mm, and 0.6 mm, respectively. Peri-implant probing depth was 1 mm after 1 year and 2 mm after 2 years. Bleeding on probing was not seen in any of the implants after 2 years. Autogenous tooth material appears to be suitable for the restoration of lateral and intraosseous defects of the alveolar ridge with both complete blocks and in particulate form. However, additional long-term studies with higher case numbers will be required for substantiating these results.

Clinical Effectiveness of the Lateral Approach of the Maxillary Sinus Floor Augmentation using Different Gadgets with Simultaneous Implant Placement: A Systematic Review with Meta-Analysis

Objectives: Help the clinician to choose between the newly introduced, specifically designed instruments for this procedure. Methods/Statistical Analysis: after thorough search of Cochrane CENTRAL and PubMed databases, the analysis was limited to clinical studies of the lateral approach sinus augmentation with simultaneous implant placement. Statistical Analysis: Comprehensive Meta Analysis version 2.2.048 software was used. Results: Eight articles were included in the review. Analysis of the formatted tables shows that the type of tool used in sinus lateral approach might affect the success of the procedure. Findings: There was a statistical significance difference of using the ultrasonic tips over the conventional use of rotary tips but it is not usually to be clinically significant; especially if a highly trained surgeon could perform the lateral osteotomy by any tool but the previous studies were highly supporting the ultrasonic tips over the rotary tips in reference to less traumatic surgery with minimal operative and postoperative complications. Application/ Improvements: Randomized clinical trials are needed to compare the newly presented tools like DASK and SLA reamers to properly asses their clinical effectiveness. Studies of patient reported outcomes are needed to clearly evaluate the cost effectiveness of each tool.

Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique

BackgroundPatients with resorbed edentulous alveolar ridges in the posterior maxilla often require lateral window sinus augmentation procedures prior to implant placement. Lateral window sinus augmentation procedures can produce incomplete bone augmentation as consequence of surgical and healing complications producing unusual and complex sinus anatomy. Although incomplete bone formation after sinus augmentation has been described in a previous case reports, this is the first case report that describes grafting these compromised sites prior to implant placement.Case presentationA 65-year-old male patient with no known medical conditions presented with severe chronic localized periodontitis and a combined periodontal-endodontic lesion affecting three first molars. Initial ridge preservation and lateral window sinus augmentation resulted in incomplete bone formation and complex sinus floor anatomy on both right and left sides. A dilating balloon technique on one side and a palatal approach on the other side were utilized for additional sinus augmentation using particulate allograft and resorbable collagen membranes. Healing was uneventful, and implants could be placed and restored at all sites. Periodontal maintenance was conducted every 3 months, and the implants have been in function and periodontally healthy for 2 years.ConclusionDespite initial failure of sinus augmentation to produce suitable implant sites, it is possible to rescue these sites with re-entry grafting procedures and allow successful implant placement and restoration.

Retrospective analysis of 10,000 implants from insertion up to 20years-analysis of implantations using augmentative procedures.

BackgroundA sufficient amount of bone is essential to ensure long-term stability of dental implants. To support the bone regeneration process, different techniques and materials are available. It has been questioned whether these techniques and materials may compromise implant survival compared to pristine bone. To properly answer this question, long-term stability up to 20.2 years after insertion of implants placed in augmented or non-augmented sites was retrospectively analysed.MethodsRetrospective analysis included 10,158 implants from 3095 patients in three private practices who underwent implant therapy with or without bone augmentation procedures. Different graft materials and membranes were used for augmentation. If necessary, the graft was stabilised using a titanium mesh. Implant survival was evaluated analysing explantation rates and Kaplan-Meier survival curves in augmented or non-augmented sites. In additional subgroup analyses, augmentation procedures, graft materials and membranes were compared applying descriptive statistics.ResultsThe observation period varied from the day of implantation up to 20.2 years after implant insertion. The overall implant survival was 95.5% (augmented sites 96.33%; native sites 94.27%). Comparison of Kaplan-Meier survival curves revealed significantly better survival of implants in augmented sites (p = 0.0025). When comparing different augmentation procedures, the best results were found for bone condensing followed by lateral augmentation. Graft materials were used in 58.2%, membranes in 36.6% of all implant sites. The most often used graft materials were a deproteinized bovine bone mineral (53.0%) and autogenous bone particles (32.5%). Both provided the best results and showed a significantly better implant survival compared to no graft material using the Kaplan-Meier method (p = 0.0104 and p < 0.0001). A native collagen membrane was used most often (74.0% of the membrane sites) and provided the best results regarding implant survival in the log-rank test.ConclusionsThe retrospective analysis shows that implants inserted in augmented or native bone demonstrate similar implant survival under the conditions of private practice compared to prospective studies. To establish a broad base of support, further well-designed clinical trials are necessary.

Computer-Assisted Analysis of Bone Volume for Sinus Augmentation Procedure

Sinus floor augmentation | Cone beam computed tomography | Graft volume measurement | Computerassisted image interpretation | Surgical simulation | Greffe sinusienne | Tomodensitométrie à faisceau conique | Simulation de greffe osseuse | Mesure volumétrique

Tubularised incised-plate versus tubularisation of an intact and laterally augmented plate for hypospadias repair: A prospective randomised study

ObjectivesTo compare the outcome of hypospadias repair using tubularised incised-plate (TIP) urethroplasty and tubularisation of an intact and laterally augmented urethral plate. Patients and methodsThis prospective randomised study included 370 patients with primary distal hypospadias. All had urethral plate widths of 8–10mm and a glans of ⩾15mm. Exclusion criteria were previous repair, circumcision, a wide urethral plate of >10mm or a narrow plate of <8mm in diameter, a small glans of <15mm in diameter, chordee of >30°, and hormonal stimulation. Patients were randomised into two groups: Group 1 (185 patients) underwent TIP urethroplasty and Group 2 (185 patients) underwent tubularisation of the intact plate with lateral augmentation of the urethral plate using penile skin. The follow-up period was 12–28months. ResultsThere were 172 evaluable patients in Group 1 and 177 in Group 2. The urethroplasty was successful in 83.2% and 94.4% in Groups 1 and 2, respectively. Complications occurred in 16.8% in Group 1 and 5.6% in Group 2 (P=0.001). Meatal stenosis occurred in 7% and 3.4% in Groups 1 and 2, respectively (P=0.130). There were statistically significant differences in the wound dehiscence, fistula, and re-operation rates of Group 1 versus Group 2, at 6% versus 0%, 9.8% versus 2.8%, and 13.4% versus 5.6%, respectively. The presence of mild chordee did not affect the complication rate (P=0.242). The mean (SD) operative time was 56.7 (8.9) min in Group 1 and 93.7 (8.3) min in Group 2 (P<0.001). ConclusionThe outcome of tubularised intact and laterally augmented plate is better than classical TIP urethroplasty of hypospadias. Further trials are mandatory to extend the indications of the technique.

Long-term effects of vertical bone augmentation: a systematic review.

ABSTRACTExtraction, periodontitis, or trauma can cause a reduction on the alveolar ridge. This could result in an insufficient alveolar bone width and height. Different techniques of vertical bone augmentation are described in literature. However, nowadays there is not enough evidence against lateral augmentation procedures to verify if these techniques are stable over a long period of time. Objective This review analyses the different techniques that are used to vertically augment the bone and evaluate if these techniques are stable over a long period of time.Material and Methods The MEDLINE-PubMed database was searched from its earliest records until December 22, 2014. The following search term was used: Alveolar Ridge augmentation [MESH]. Several journals were hand searched and some authors were contacted for additional information. The primary outcome measure that was analyzed was marginal bone level change around dental implants in the augmented sites, and the secondary outcomes were survival and success rates of dental implants placed in the augmented sites.Results The search yielded 203 abstracts. Ultimately, 90 articles were selected, describing 51 studies meeting the eligibility criteria. The marginal bone level change for the inlay technique and vertical guided bone regeneration are in agreement with the success criteria. Alveolar distraction showed more marginal bone level change after the first year of loading, and for the inlay technique very few studies were available.Conclusions Based on the available data in the current existing studies with a follow-up period of at least 4 to 5 years, one can summarize that there seems to be a trend that the onlay technique, alveolar distraction, and vertical guided bone regeneration are stable for at least 4 to 5 years.

Continuous delivery of rhBMP2 and rhVEGF165 at a certain ratio enhances bone formation in mandibular defects over the delivery of rhBMP2 alone — An experimental study in rats

The aim of the present study was to test the hypothesis that different amounts of vascular endothelial growth factor and bone morphogenic protein differentially affect bone formation when applied for repair of non-healing defects in the rat mandible. Porous composite PDLLA/CaCO3 carriers were fabricated as slow release carriers and loaded with rhBMP2 and rhVEGF165 in 10 different dosage combinations using gas foaming with supercritical carbon dioxide. They were implanted in non-healing defects of the mandibles of 132 adult Wistar rats with additional lateral augmentation. Bone formation was assessed both radiographically (bone volume) and by histomorphometry (bone density). The use of carriers with a ratio of delivery of VEGF/BMP between 0.7 and 1.2 was significantly related to the occurrence of significant increases in radiographic bone volume and/or histologic bone density compared to the use of carriers with a ratio of delivery of ≤0.5 when all intervals and all outcome parameters were considered. Moreover, simultaneous delivery at this ratio helped to “save” rhBMP2 as both bone volume and bone density after 13weeks were reached/surpassed using half the dosage required for rhBMP2 alone. It is concluded, that the combined delivery of rhVEGF165 and rhBMP2 for repair of critical size mandibular defects can significantly enhance volume and density of bone formation over delivery of rhBMP2 alone. It appears from the present results that continuous simultaneous delivery of rhVEGF165 and rhBMP2 at a ratio of approximately 1 is favourable for the enhancement of bone formation.

Staged ridge-split evaluated using cone beam computed tomography and peri-implant plastic surgery in the mandibular arch

AbstractLack of sufficient bone to place an implant at a functionally and an esthetically appropriate position is a common problem, especially in the mandibular posterior region. Narrow edentulous alveolar ridges &lt;5 mm wide require bone augmentation before implant placement to establish a bony wall of at least 1 mm around the endosseous implant. Various surgical widening techniques are available, including lateral augmentation with or without guided bone regeneration, ridge-split technique and horizontal distraction osteogenesis. The ridge-split technique aims at creating a new implant bed by longitudinal osteotomy of the alveolar bone. The buccal cortex is repositioned laterally by greenstick fracture, and the space between the buccal and lingual cortices is filled with a graft material. Peri-implant plastic surgery focuses on harmonizing peri-implant structures by means of hard- and soft-tissue engineering and includes bone structure enhancement, soft-tissue enhancement, precision in implant placement and improves quality of the prosthetic restoration. The rationale for the peri-implant plastic surgery approach goes well beyond pure esthetics as it creates peri-implant keratinized mucosa and interimplant soft-tissue height in order to avoid food impaction, interimplant airflow, and speech problems. This case report demonstrates a staged ridge-split technique evaluated with cone beam computed tomography using a piezosurgical unit and a surgical technique to restore a papilla-like tissue at the time of the second-stage implant surgery.

Implant treatment planning regarding augmentation procedures: panoramic radiographs vs. cone beam computed tomography images.

To evaluate the impact of cone beam computed tomography (CBCT) imaging on treatment planning regarding augmentation procedures for implant placement. Panoramic radiographs and CBCT images of 40 patients requesting single-tooth implants in 59 sites were retrospectively analyzed by six specialists in implantology, and treatment planning was performed. Therapeutic recommendations were compared with the surgical protocol performed initially. Bone height estimation from panoramic radiographs yielded to higher measures and greater variability compared to CBCT. The suggested treatment plan for lateral and vertical augmentation procedures based on CBCT or panoramic radiographs coincided for 55-72% of the cases. A trend to a more invasive augmentation procedure was seen when planning was based on CBCT. Panoramic radiography revealed 57-63% (lateral) vs. 67% (vertical augmentation) congruent plans in agreement with surgery. Among the dissenting sites, there was a trend toward less invasive planning for lateral augmentation with panoramic radiographs, while vertical augmentation requirements were more frequently more invasive when based on CBCT. Vertical augmentation requirements can be adequately determined from panoramic radiographs. In difficult cases with a deficient lateral alveolar bone, the augmentation schedule may better be evaluated from CBCT to avoid underestimation, which occurs more frequently when based on panoramic radiographs only. However, overall, radiographic interpretation and diagnostic thinking accuracy seem to be mainly depending on the opinion of observers.

The outcome of intraoral onlay block bone grafts on alveolar ridge augmentations: a systematic review.

Aim: The purpose of this study was to systematically review clinical studies examining the survival and success rates of implants placed with intraoral onlay autogenous bone grafts to answer the following question: do ridge augmentations procedures with intraoral onlay block bone grafts in conjunction with or prior to implant placement influence implant outcome when compared with a control group (guided bone regeneration, alveolar distraction, native bone or short dental implants.)? Material and Method: An electronic data banks and hand searching were used to find relevant articles on vertical and lateral augmentation procedures performed with intraoral onlay block bone grafts for dental implant therapy published up to October 2013. Publications in English, on human subjects, with a controlled study design –involving at least one group with defects treated with intraoral onlay block bone grafts, more than five patients and a minimum follow-up of 12 months after prosthetic loading were included. Two reviewers extracted the data. Results: A total of 6 studies met the inclusion criteria: 4 studies on horizontal augmentation and 2 studies on vertical augmentation. Intraoperative complications were not reported. Most common postsurgical complications included mainly mucosal dehiscences (4 studies), bone graft or membrane exposures (3 studies), complete failures of block grafts (2 studies) and neurosensory alterations (4 studies). For lateral augmentation procedures, implant survival rates ranged from 96.9% to 100%, while for vertical augmentation they ranged from 89.5% to 100%. None article studied the soft tissues healing. Conclusions: Survival and success rates of implants placed in horizontally and vertically resorbed edentulous ridges reconstructed with block bone grafts are similar to those of implants placed in native bone, in distracted sites or with guided bone regeneration. More surgical challenges and morbidity arise from vertical augmentations, thus short implants may be a feasible option. Key words:Alveolar ridge augmentation, intraoral bone grafts, onlay grafts, block grafts, dental implants.

Tissue reactions after simultaneous alveolar ridge augmentation with biphasic calcium phosphate and implant insertion--histological and immunohistochemical evaluation in humans.

Simultaneous lateral augmentation and implant placement is considered as standard procedure in deficient edentulous ridges in oral implantology. Histological studies monitoring osteogenesis after application of alloplastic bone substitutes in humans are scarce. Bone formation upon simultaneous augmentation with biphasic calcium phosphate (BCP) and implantation was histologically investigated after 6months in situ. The results of this secondary analysis are reported tempting to ascribe specific observations to uneventful submerged healing or compromised healing of soft tissues including occurrence of dehiscences and premature graft exposure. Histology of biopsies from lateral, crestal bone augmentations using alloplastic BCP comprising seven sites with compromised, prematurely exposed healing and six sites with uneventful submerged healing was investigated for expression of osteogenic, osteoclastogenic, and angiogenic differentiation markers. Histology revealed alkaline phosphatase (ALP)-positive osteoblasts and immunoreactivity for osteogenic markers osteocalcin and collagen type I in biopsies with submerged healing, while inflammatory infiltrates and accumulations of multinucleated giant cells around BCP granules were observed in compromised sites. All specimens presented adequate vessel density. Multinucleated giant cells showed inconsistent staining for the osteoclast marker tartrate-resistant acid phosphatase (TRAP). The histological findings of this study indicate an osteoconductive nature of the BCP applied. Premature exposure of the bone substitute reduced new bone formation and may bear a risk for inflammatory and foreign body reactions. A predictable appositional bone formation in simultaneously augmented sites using BCP is linked to an uneventful healing process.

Ridge splitting technique for horizontal augmentation and immediate implant placement

Insufficient width of the alveolar ridge often prevents ideal implant placement. Guided bone regeneration, bone grafting, alveolar ridge splitting and combinations of these techniques are used for the lateral augmentation of the alveolar ridge. Ridge splitting is a minimally invasive technique indicated for alveolar ridges with adequate height, which enables immediate implant placement and eliminates morbidity and overall treatment time. The classical approach of the technique involves splitting the alveolar ridge into 2 parts with use of ostetomes and chisels. Modifications of this technique include the use of rotating instrument, screw spreaders, horizontal spreaders and ultrasonic device. The purpose of this article is to thoroughly describe all the different approaches in ridge splitting technique. 2 interesting clinical cases of narrow alveolar ridges treated with ridge splitting and immediate implant placement are also presented.

The Monocortical Window (MCW): A Modified Split-Crest Technique Adopting Ligature Osteosynthesis

Split-crest procedures performed with ultrasonic devices have proven to be a viable and effective surgical treatment when the alveolar ridge shows forms of resorption in thickness while its height remains virtually unchanged. However, in the case of stiff, type 1, corticalized mandibular bone, it may be very difficult or even impossible to have any elasticity and lateral augmentation in between the split bone walls. Furthermore, a complete detachment of the outer lamellae may also occur during expansion maneuvers or during implant insertion. This study describes the use of a steel-wire ligature osteosynthesis technique to give primary stability both to the expanded cortical window and to the implants themselves when they have none at all. This osteosynthesis is simple, quick, safe, and bone-saving in force delivery. It is also extremely cheap as well as being effective in obtaining ridge expansion, bone regeneration, and implant positioning in an all-in-one procedure. This article describes the foundations in the literature as well as new elements in the technique. Three short case studies are used by way of example.

Current perspectives on the role of ridge (socket) preservation procedures in dental implant treatment in the aesthetic zone

Augmentation of the extraction socket (ridge preservation) is increasingly being advocated in anticipation of implant placement. The aim of this article is to review the available evidence with regards to ridge preservation procedures, investigating whether these techniques improve dental implant treatment outcomes. Evidence is examined to compare these techniques to other treatment alternatives such as implant placement with simultaneous lateral augmentation. An electronic PubMed search was conducted using search terms relevant to assessing treatment outcomes in association with ridge preservation. Titles were screened and full text obtained where relevant. Further full text articles were obtained from analysis of those papers yielded from the original search. Twenty-two papers were finally selected for analysis. Ridge preservation techniques are effective in minimizing post-extraction alveolar ridge contraction. However, there is insufficient evidence to suggest that the use of these techniques in conjunction with dental implant treatment improves implant treatment outcomes. Furthermore, ridge preservation does not necessarily eliminate the need for further simultaneous augmentation at the time of implant placement. The delayed healing associated with ridge preservation using socket grafting necessitates a commitment to a delayed placement protocol. The extended treatment time, compromised healing and expense related to ridge preservation suggests a more cautious approach with regards to the indication of such techniques.

The Optimization of Lateral Control Augmentation Based on Genetic Algorithms

The control augmentation systems are very important to keep the stability and manipulability in the flight control systems. The general flight control laws are designed by static designs and dynamic fits. To improve the adaptive capability, a new method of control laws design was introduced by using dynamic optimization genetic algorithms. The control parameters were adjusted online in the flight envelope. The dynamic optimization model was built for aircraft lateral control augmentation function. The control parameters were regulated by dynamic optimization genetic algorithms. Finally an example of a lateral flight control augmentation system of an aircraft is used with a simulation. The simulation results show the proposed method is achievement. DOI: http://dx.doi.org/10.11591/telkomnika.v11i6.2601

A randomized and controlled clinical trial of two different compositions of deproteinized bovine bone and autogenous bone used for lateral ridge augmentation

The aim of the study was to radiologically and histologically evaluate the graft healing and volumetric changes after lateral augmentation with two different compositions of deproteinized bovine bone (DPBB) and autogenous bone (AB). Thirteen patients with a mean age of 59.6±12.1years (six men and seven women) were included in this randomized and controlled trial, designed as a split-mouth study. Ten edentulous and four partially edentulous jaws with an alveolar ridge width of ≤4mm were laterally augmented with a graft composition of 60:40 (DPBB/AB) on one side and 90:10 (DPBB/AB) on the contralateral side. Cone beam computed tomography (CB/CT) was obtained immediately postoperatively and after a healing period of 7.5months. Width changes were measured on CB/CT scans. After a mean healing period of 8.1months (range, 7.9-8.3), biopsies were retrieved perpendicular to the crest from each graft by means of a trephine bur. Histomorphometry was performed, and the following variables were recorded: Ingrowth of new bone (percentage of total graft width), percentage of DPBB, bone and soft tissue, and percentage of DPBB particles in contact with bone. The mean gained width of the alveolar crest after 7.5months was significantly more for the 60:40 mixture compared with the 90:10 mixture, 3.5 (±1.3) mm and 2.9 (±1.3) mm, respectively. There was a significant difference in graft width reduction between 60:40 and 90:10 after 7.5months, 37 (±19.9)% and 46.9 (±23.5)%, respectively. New bone ingrowth had occurred in 82.1 (±23.3)% and 82.3 (±26.6)% of the graft, respectively. There were no statistical differences between fractions of different tissues between the 90:10 and 60:40 compositions. However, there were significantly more soft tissue and less new bone formation closer to the periosteum compared with the graft portion closer to the residual bone in both 60:40 and 90:10 compositions. There was significantly less graft width reduction with a mixture of 60:40 (DPBB/AB) compared with a mixture of 90:10 composition, but the results from the histomorphometry showed no statistical differences comparing the groups.

Bone-Forming Capabilities of a Newly Developed NanoHA Composite Alloplast Infused with Collagen: A Pilot Study in the Sheep Mandible

Lateral or vertical bone augmentation has always been a challenge, since the site is exposed to constant pressure from the soft tissue, and blood supply only exists from the donor site. Although, for such clinical cases, onlay grafting with autogenous bone is commonly selected, the invasiveness of the secondary surgical site and the relatively fast resorption rate have been reported as a drawback, which motivated the investigation of alternative approaches. This study evaluated the bone-forming capability of a novel nanoHA alloplast infused with collagen graft material made from biodegradable polylactic acid/polyglycolic acid versus a control graft material with the same synthesized alloplast without the nanoHA component and collagen infiltration. The status of newly formed bone and the resorption of the graft material were evaluated at 6 weeks in vivo histologically and three dimensionally by means of 3D microcomputed tomography. The histologic observation showed that newly formed bone ingrowth and internal resorption of the block were observed for the experimental blocks, whereas for the control blocks less bone ingrowth occurred along with lower resorption rate of the block material. The three-dimensional observation indicated that the experimental block maintained the external geometry, but at the same time successfully altered the graft material into bone. It is suggested that the combination of numerous factors contributed to the bone ingrowth and the novel development could be an alternative bone grafting choice.