Resorbable Collagen Membrane Research Articles

O040: Randomized clinical trial comparing two resorbable collagen membranes demonstrates good bone formation and soft tissue healing with GBR at single implant sites with dehiscence defects

O040: Randomized clinical trial comparing two resorbable collagen membranes demonstrates good bone formation and soft tissue healing with GBR at single implant sites with dehiscence defects

Feasibility of using allograft bone with resorbable collagen membrane for alveolar ridge vertical defect augmentation for dental implant placement in Patient with Aggressive Periodontitis: A case report

PurposeThis case report demonstrates the feasibility of using allograft bone with a resorbable collagen membrane to correct an alveolar ridge defect and achieve a highly esthetic restoration. Case presentationA 30-year-old woman with generalized aggressive periodontitis and advanced periodontal vertical bone loss in periodontally hopeless upper left right premolar which required a fixed restoration. A staged surgical strategy was devised. First, a resorbable collagen membrane and allograft bone grafts were used to guide bone regeneration in the vertical alveolar defect. After 6 months, complete bone regeneration was achieved and the dental implants were submerged in the bone. Three months later, the implants were exposed and subsequently restored with a crown. ConclusionThe vertical guided bone regeneration strategy of using allograft bone and a resorbable collagen membrane has the potential to eliminate the need for additional procedures, which are required with non-resorbable membranes, sinus lift procedures, and extensive block graft procedures.

Guided bone regeneration in calvarial critical size bony defect using a double-layer resorbable collagen membrane covering a xenograft: a histological and histomorphometric study in rats.

The aim of the present study was to evaluate histologically and histomorphometrically the bone regeneration in critical size calvarial defects in rats grafted with either a deproteinized bovine bone mineral (DBBM) alone or in combination with a single or double layer of native bilayer collagen membrane (NBCM). The secondary objective was to evaluate histologically and histomorphometrically the residual DBBM in these defects. Thirty-two Wistar rats were divided into two groups: a control group of 16 rats with two critical size calvarial defects (CSD) of 5mm performed each on either side of the median sagittal suture, where the frontal defect remained without any filling (negative control), while the occipital defect (positive control) was filled with DBBM; and then a test group of 16 rats, with two CSD filled with DBBM and covered by either a single (SM) or a double layer (DM) of NBCM. The animals were sacrificed at 4 and 8weeks. At 1month, the histological and histomorphometric analysis showed new bone formation (NBF) in the defects that received only DBBM, DBBM+DM, and DBBM+SM (11.5, 17.3, and 22.7%, respectively), while the negative control defects showed only 0.4% of new bone formation. At 2months, the histological and histomorphometric analysis showed NBF in the defects that received only DBBM, DBBM+DM, and DBBM+SM (16.8, 24.5, and 37%, respectively), while the negative control defects showed only 0.9% of new bone formation. The residual xenogeneic material (RXM) was higher in defects covered by SM (30.2% at 1month and 25.3% at 2months) or DM (32.5% at 1month and 28.5% at 2months) compared with defects that were not covered by membranes (15.3% at 1month and 9.4% at 2months). This study demonstrated that GBR with a xenogeneic material in rat calvarial (CSD) of 5mm requires the application of resorbable collagen membranes in either single or double layer, and a single layer alone is sufficient to promote this regeneration.

Dental Implants Placed in Alveolar Ridge Augmented Using Guided Bone Regeneration Procedure Performed Using Resorbable Collagen Membranes and Particulate Bone Grafts Using Simultaneous or Staged Approach Exhibit a High Survival Rate

Guided bone regeneration with collagen membranes and particulate graft materials: A systematic review and meta-analysis. Wessing B, Lettner S, Zechner W. Int J Oral Maxillofac Implants 2018;33(1):87-100. Did not receive any funding support TYPE OF STUDY/DESIGN: Systematic review with meta-analysis of data.

Guided Bone Regeneration of Femoral Segmental Defects using Equine Bone Graft: An In-Vivo Micro-Computed Tomographic Study in Rats

ABSTRACTBackground and objectives: Guided bone regeneration (GBR) is commonly used for osseous defect reconstruction. The objective of this study was to evaluate in real-time (in-vivo) the efficacy of equine bone graft for GBR in segmental critical-size defects (CSD) of the femur in a rat model. Materials and methods: Following ethical approval, 30 male Wistar-Albino rats (age 12–14 months/weight 450–500 grams) were included. Under general-anesthesia, a mid-diaphyseal segmental CSD (5 mm) was created in the femur and stabilized using titanium Miniplate(4 holes,1.0 mm thickness). Depending upon material used for GBR, animals were randomly divided into three groups(n = 10/per group). Negative control-Defect covered with resorbable collagen membrane(RCM); Positive control-Defect filled with autologous bone and covered by RCM; Equine bone-Defect filled with equine bone and covered by RCM. Real-time in-vivo Micro-CT was performed at baseline, 2, 4, 6 and 8 weeks to determine volume and mineral density of newly formed bone (NFB) and remaining bone graft particles (BGP). Results: In-vivo micro-CT revealed increase in volume and mineral density of NFB within defects from baseline to 8-weeks in all groups. At 8-weeks NFB-volume in the equine bone group(53.24 ± 13.83 mm3; p < 0.01) was significantly higher than the negative control(5.6 ± 1.06 mm3) and positive control(26.07 ± 5.44 mm3) groups. Similarly, NFB-mineral density in the equine bone group(3.33 ± 0.48 g/mm3; p < 0.01) was higher than the other (negative control–0.27 ± 0.02 g/mm3; positive control–2.55 ± 0.6 g/mm3). A gradual decrease in the BGP-volume and BGP-mineral density was observed. Conclusion: The use of equine bone for GBR in femoral segmental defects in rats, results in predictable new bone formation as early as 2-weeks after bone graft placement.

A Retrospective Tomographic and Histologic Analysis of Horizontal Bone Augmentation in Maxillary Atrophic Ridges Using Resorbable Membrane with Anorganic Bovine Bone-Derived Mineral and Plasma Rich in Growth Factors.

A total of six patients treated from 2010 to 2014, having a knife-edge ridge (Cawood-Howell Class IV resorbed ridges) and requiring an implant-prosthetic rehabilitation, were selected. Tomographic measurement of the edentulous ridges was performed before grafting and after implant placement. At 6 months postgraft, a total of 41 implants had been inserted, 17 in the posterior region, 12 in the central region, and 12 in the anterior region. No surgical or healing complications were recorded, and the prostheses were loaded 6 to 9 months after implant placement. The tomographic measurements demonstrated an increased area in all the sites where bone augmentation had been performed, corresponding to 11.1% in the anterior region, 94.7% in the central region, and 760.2% in the posterior region. Histology was performed in 2 patients, one at 1 year and the other at 5 years postgrafting, and demonstrated the presence of mature lamellar bone tissue and newly formed bone without morphologic signs of necrosis or inflammation and a reduction of 50% to 30% of the grafted material. Although this study included a small number of clinical cases, it demonstrated how management of the atrophic maxillary ridge, with the goal of implant placement, may be handled using a technique that requires a single anorganic bovine bone-derived mineral treatment combined with a plasma rich in growth factors and resorbable collagen membrane.

Lateral bone augmentation in narrow posterior mandibles, description of a novel approach, and analysis of results.

Combination of particulate grafts and collagen membranes is widely used for augmentation of bony defects for implant placement. Fixation of the barrier membrane may avoid complications due to unfavorable mechanical properties and poor stability leading to collapse of the augmented area. To evaluate a new simplified method for resorbable collagen membrane fixation in lateral bone augmentation procedures in narrow posterior mandibles. This retrospective study analyzed 16 procedures performed in 15 patients who followed lateral ridge augmentation procedures before implant placement in the posterior mandible. A particulate mineralized bone allograft was covered with a cross-linked resorbable collagen barrier membrane, which was fixated with a single, nonresorbable pin. Complications were registered and results analyzed on pre and post op measurements on computerized tomographic scans. Descriptive statistical analysis and ANOVA with repeated measures were performed. No complications were recorded. Average bone gain was 3.3 mm at implant platform level and 4.29 mm at 3 mm apically, both, statistically significant. All sites had sufficient bone width allowing implant placement. Thirty-three implants placed in the augmented areas, integrated and survived for over a 2-year follow-up. The simplified membrane fixation procedure enables large horizontal bone gain with minimal complications while allowing adequate implant placement.

Clinical Performance of Moldable Bioceramics and Resorbable Membrane for Bone and Mucosa Regeneration in Maxillofacial Surgery

The objectives are to present the novel concept of moldable injectable osteogenic CaP bioceramic, and the data issued from a non-interventional study to demonstrate the efficacy of an injectable bone substitute (bioceramic/hydrogel) in association with a collagen resorbable membrane and the performance to guide bone regeneration and soft tissue healing in maxillofacial surgery. Historically, dental implantology required both bone augmentation and reconstruction. However, with the aging of the population, it is also necessary to prevent the bone loss after dental extraction. To overcome the limitations associated with autografts, several bone substitutes have been developed. However, there are still numerous difficulties in the handling, reproducibility of the resorption, and bone regeneration associated with the biomaterials. Therefore, it is important to optimize new bone substitute technologies. Bioactive injectable bioceramics, particularly putties, are often used in these applications. In this preclinical and clinical study, we demonstrate the efficacy and the performance of a combined use of calcium phosphate microporous granules and hydrosoluble polymers for maxillofacial bone reconstruction and regeneration. The biomaterial was extruded into bone defects and recovered by aresorbable porcine collagen membrane, after tooth extractions in 78 patients. The clinical follow-up revealed no incidents or complications. Furthermore, infections or foreign body reactions were not reported during the 17 months of follow-up. We analyzed the drilling waste taken from 11 patients during the dental implantation sequence (at 5-10 months). Resorption and bone ingrowth were assessed using microtomography, scanning electron microscopy, light microscopy, and image analysis. We found that the highly kinetic process of resorption/absorption and bone in growth was achieved within a few months. The bone ingrowth was architectured and well vascularized.

Effect of flapless ridge preservation with two different alloplastic materials in sockets with buccal dehiscence defects-volumetric and linear changes.

To test whether or not one out of two alloplastic materials used for ridge preservation (RP) is superior to the other in terms of volumetric and linear ridge changes over time. In 16 adult beagle dogs, the distal roots of P3 and P4 were extracted and 50% of the buccal bone plate removed. Ridge preservation was performed randomly using two different alloplastic bone grafting substitutes (poly lactic-co-glycolic acid (PLGA) coated biphasic calcium phosphate particles consisting of 60% hydroxyapatite (HA) and 40% beta-tricalcium phosphate (ß-TCP=test 1), (a biphasic calcium phosphate consisting 60% HA and 40% ß-TCP=test 2) and a resorbable collagen membrane or a control group (sham). Sacrifice was performed at three time-points (4, 8, 16weeks later). Impressions were taken before extraction, after RP, and at sacrifice, allowing for assessment of volumetric changes. A multi-way ANOVA was computed, and partial Type-II F tests were performed. Both ridge preservation procedures minimized the volume loss compared to spontaneous healing. The median buccal volume changes between pre-extraction and sacrifice were - 1.76mm (Q1 = - 2.56; Q3 = - 1.42) for test 1, - 1.62mm (Q1 = - 2.06; Q3 = - 1.38) for test 2, and - 2.42mm (Q1 = - 2.63; Q3 = - 2.03) for control. The mean ridge width measurements did not show statistically significant differences between test 1 (- 2.51mm; Q1 = - 3.25; Q3 = - 1.70) and test 2 (- 2.04mm; Q1 = - 3.82; Q3 = - 1.81) (p = 0.813), but between test and control (- 3.85mm; Q1 = - 5.02; Q3 = - 3.27) (p = 0.003). Both RP techniques were successful in maintaining the buccal contour from pre-extraction to sacrifice to a similar extent and more favorable compared to spontaneous healing. Alloplastic materials can successfully be used for RP procedures.

Sugar-based collagen membrane cross-linking increases barrier capacity of membranes.

This study examines the permeability and barrier capacity of a sugar cross-linked resorbable collagen membrane ex vivo and in vivo. In an ex vivo study, injectable platelet-rich fibrin (i-PRF), a peripheral blood-derived human leukocyte-and-platelet-rich plasma was used to analyze membrane permeability. in vivo subcutaneous implantation in Wistar rats (n = 4 per time point and group) was used to investigate the barrier capacity of the membrane. The induced in vivo cellular reaction was evaluated at 3, 15, and 30days and compared to sham OP (control) without biomaterial using histological, immunohistochemical, and histomorphometric methods. Ex vivo, the membrane was impenetrable to leukocytes, platelets, and fibrin from peripheral human blood concentrate (PRF). In vivo, the membrane maintained its structure and remained impervious to cells, connective tissue, and vessels over 30days. CD-68-positive cell (macrophage) numbers significantly decreased from 3 to 15days, while from day 15 onwards, the number of multinucleated giant cells (MNGCs) increased significantly. Correspondingly, a rise in implantation bed vascularization from 15 to 30days was observed. However, no signs of degradation or material breakdown were observed at any time point. Ex vivo and in vivo results showed material impermeability to cellular infiltration of human and murine cells, which highlights the membrane capacity to serve as a barrier over 30days. However, whether the induced MNGCs will lead to material degradation or encapsulation over the long term requires further investigation. The data presented are of great clinical interest, as they contribute to the ongoing discussion concerning to what extent an implanted material should be integrated versus serving only as a barrier membrane.

A new approach to treat bone gaps after midfacial and zygomatic fractures with a collagen membrane.

The aim of the study was to analyze the eligibility of resorbable collagen membrane in the treatment of midfacial fractures to prevent gap formation and subsequent cheek tissue retraction. We included nine patients (six males, three females; mean age 51; range 20-73years; mean bone gap size 8.03×13.12mm) in a retrospective study design. The defect size was assessed by ultrasound. After a healing period of 4 to 55weeks, treatment resulted in a significant reduction of gap size (residual mean bone gap size 6.14×7.32mm). Native resorbable collagen membrane is a promising tool to reduce the size of bony gap in midfacial defects.

How effective is collagen resorbable membrane placement after partially impacted mandibular third molar surgery on postoperative morbidity? A prospective randomized comparative study

BackgroundCollagen membranes have some benefits include promoting wound healing through isolation, clot stabilization, wound stability, and hemostasis, enhancing primary wound coverage through its chemotactic ability to attract fibroblasts, and augmenting flap thickness by providing a collagenous scaffold. The purpose of this study was to compare primary and secondary healing and collagen membrane-based primary healing after surgical removal of partial impacted mandibular third molars, evaluating the incidence of postoperative complications and analyzing the swelling, mouth opening, and pain.MethodsThis was a prospective, randomized controlled study. Patients were randomly assigned to three groups: the SC (Secondary closure) group, the PC (Primary closure) group, and the MBPC (membrane based primary closure) group. Data were collected on pain, mouth opening, swelling, and complications experienced by the patients.ResultsThere was no statistically significant difference between the groups for the pain (p > 0.05), relatively. The swelling recorded on postoperative days 2 and 7 was lower in the SC group than in the PC (p = 0.046 and 0.00) and in MBPC (p = 0.005 and 0.002) groups, respectively. Mouth opening showed a statistically significant difference between the three groups at day 2 (p = 0.00). Wound dehiscence was shown in 6 patients in the PC (20%) group and 2 patients in the MBPC (6.7%) group. Dry socket was observed 3 patients in the SC group (10%), 2 patients in the PC group (6.7%), and no dry socket in the MBPC group. No cases of infection or postoperative bleeding were encountered.ConclusionsThe secondary closure provides a marked advantage over the primary closure in terms of swelling and mouth opening. However, the absence of alveolitis in the primary closure using the collagen membrane and minimal wound dehiscence, suggests that membrane use may support primary healing in terms of wound healing.

Contour changes after guided bone regeneration of large non-contained mandibular buccal bone defects using deproteinized bovine bone mineral and a porcine-derived collagen membrane: an experimental in vivo investigation.

The objective of this study was to evaluate soft tissue contour changes after three different regenerative therapies in chronic ridge defects. Buccal bone defects were created in the mandible of nine beagle dogs. Augmentation procedures were performed 3months later using a bone replacement graft (BRG), resorbable collagen membrane (MBG), or a combination of both procedures (CBG). Silicone impressions were taken before tooth extraction (T1), before the augmentation procedure (T2), and 3months after the regenerative surgeries (T3). Casts were optically scanned and stereolithography files were superimposed to analyze the horizontal changes in ridge contours. After defect creation, most part of the horizontal changes occurred 4 and 6mm below the gingival margin. In the mesial defect (D1) at T3, the mean horizontal gain in MBG amounted to 0.47±0.34mm, 0.79±0.67mm in the BRG, and 0.87±0.69mm for the CBG. In the middle defect (D2), the mean changes for the MBG were 0.11±0.31, 1.01±0.91 for the BRG, and 0.98±0.49 for the CBG. The mean changes in the distal defect (D3) amounted to 0.24±0.72 for the MBG, 1.04±0.92 for the BRG, and 0.86±0.56 for the CBG. The differences reached significance in all defects for the comparison MBG-BRG and MBG-CBG, while similar parameters were observed for the comparison BRG-CBG. BRG and CBG were equally effective and superior to MBG in increasing the horizontal tissue contours. The augmentation seldom reached the values before extraction. Scaffolding materials are needed for contour augmentation when using resorbable collagen membranes.

Densitometric analysis of prf vs xenograft for sinus augmentation procedures 5 years follow‐up

Background: The autologous platelet concentrates Platelet-Rich Plasma (PRP) and Platelet-Rich Fibrin (PRF) are used in various medical fields, particularly in oral and maxillofacial surgery. Platelet-rich fibrin (PRF) is derived from an autogenous preparation of concentrated platelets that containes high levels of polypeptide growth factors and therefore has the potential to be used as regenerative treatment for bone defects. Growth factors are the key elements in wound healing, particularly in bone regeneration. Aim: The purpose of this study was to examine the suitability of autologous PRF in combination with xenograft as regenerative treatment for maxillary sinus augmentation in humans and compare it to xenograft alone using densitometric measurements. Material and methods: The sample of presented study consists of 10 patients partially edentoulous in the lateral region of the upper jaw. Lateral approach for maxillary sinus augmentation with immediate placement of two dental implants were used in all of 10 patients. In the first group of 5 patients sinus augmentation was performed using xenographic bone graft (Bio-Oss®, Geistlich, Germany) only and finally covered with resorbable collagen membrane (Bio-Gide®, Geistlich, Germany). In the second group of 5 patients sinus augmentation was performed using combination of autologous PRF and xenograft (Bio-Oss®, Geistlich, Germany) and covered using combination of resorbable collagen membrane (Bio-Gide®, Geistlich, Germany) and PRF membrane. Following the healing period of 6 months, the osseointegration of inserted implants was assessed with resonance frequency analysis and considered adequate. All inserted implants were loaded with metal-ceramic restorations. All patients were followed for 24 months after loading through clinical follow-ups and digital radiographic imaging after 6, 12, 18 and 24 months. Densitometric analysis was done based on radiographic images. Results: After comparing the average densities of all inserted implants, the results showed statistically significant increase of density in group of patients where combination of xenograft and autologous PRF for sinus augmentation was used. Conclusions and clinical implications: The results of this study indicate that PRF can improve densitometric parameters associated with maxillary sinus floor elevation procedures and immediate implant placement, improving clinical implant stability and promoting bone healing following augmentation. PRF can be used as an effective modality for promoting bone healing and osseointegration process.

Randomized clinical trial: a resorbable collagen membrane for GBR at sites with dehiscence defects

Randomized clinical trial: a resorbable collagen membrane for GBR at sites with dehiscence defects

Guided Bone Regeneration with Collagen Membranes and Particulate Graft Materials: A Systematic Review and Meta-Analysis.

The aim of this meta-analysis was to evaluate different methods for guided bone regeneration using collagen membranes and particulate grafting materials in implant dentistry. An electronic database search and hand search were performed for all relevant articles dealing with guided bone regeneration in implant dentistry published between 1980 and 2014. Only randomized clinical trials and prospective controlled studies were included. The primary outcomes of interest were survival rates, membrane exposure rates, bone gain/defect reduction, and vertical bone loss at follow-up. A meta-analysis was performed to determine the effects of presence of membrane cross-linking, timing of implant placement, membrane fixation, and decortication. Twenty studies met the inclusion criteria. Implant survival rates were similar between simultaneous and subsequent implant placement. The membrane exposure rate of cross-linked membranes was approximately 30% higher than that of non-cross-linked membranes. The use of anorganic bovine bone mineral led to sufficient newly regenerated bone and high implant survival rates. Membrane fixation was weakly associated with increased vertical bone gain, and decortication led to higher horizontal bone gain (defect depth). Guided bone regeneration with particulate graft materials and resorbable collagen membranes is an effective technique for lateral alveolar ridge augmentation. Because implant survival rates for simultaneous and subsequent implant placement were similar, simultaneous implant placement is recommended when possible. Additional techniques like membrane fixation and decortication may represent beneficial implications for the practice.

How Effective Is the Tent Screw Pole Technique Compared to Other Forms of Horizontal Ridge Augmentation?

The tent screw pole technique is one of the methods available for practitioners to perform horizontal ridge augmentation to facilitate dental implant placement. The purpose of this study was to evaluate the efficacy of the tent screw pole technique for horizontal ridge augmentation and to compare the results with those of the tunnel technique and open ridge augmentation. In this retrospective cohort study, 35 patients underwent horizontal ridge augmentation with the tent screw pole technique, a 1:1 ratio of mineralized freeze-dried bone allograft and particulate bovine hydroxyapatite, and a resorbable collagen membrane. The incidence of early wound dehiscence and membrane exposure, the number of courses of antibiotics and postoperative visits required for their management, and the number of sites that subsequently had successful implant placement were recorded. These parameters were compared with those in 21 patients who had undergone horizontal ridge augmentation by the tunnel technique and 31 patients who had been treated using an open procedure and a resorbable polytetrafluoroethylene (PTFE) membrane in the authors' previous study (J Oral Maxillofac Surg 74:1752, 2016). Implant placement rate was similar for all 3 methods (71 to 97%). However, there were significant differences among the 3 surgical techniques for membrane exposure and wound dehiscence (P=.0033), graft loss (P=.0256), courses of antibiotics (P=.0017), and postoperative visits (P=.0043). The PTFE method consistently had the highest rate of complications, whereas the tent screw and tunnel techniques were comparable. All 3 techniques allowed a high rate of implant placement; however, the PTFE technique was consistently associated with increased postoperative complications compared with the other 2 methods. The tent screw technique might be more favorable than the tunnel technique in cases in which the bony deficiency is flat.

Effects of bone grafting, performed with corticotomies and buccal tooth movements, on dehiscence formation in dogs.

A randomized split-mouth experiment was performed in dogs to determine the effects of bone grafting, together with corticotomies and buccal tooth movements, on dehiscence formation. Bilateral full-thickness mucoperiosteal buccal flaps were raised, and corticotomies were performed with a piezosurgery unit adjacent to the maxillary second premolars in 7 dogs. The experimental (graft+) sidereceived a demineralized freeze-dried allograph and a resorbable collagen membrane. The second premolars were expanded with archwires for 9weeks, followed by 3weeks of consolidation. Soft tissue measurements included probing depths, attachment loss, and recession. Tooth movements were monitored using intraoral, radiographic, and model measurements. Bone surrounding the second premolars was evaluated with microcomputed tomography. New bone formation was analyzed histologically using calcein and alizarin fluorescent labels, and hematoxylin and eosin stains. Postsurgical healing progressed normally with no signs of infection. The graft+ and control (graft-) second premolars underwent similar amounts of expansion (about 2.5mm intraorally; about 1.7mm radiographically) and tipping, with no statistically significant side differences. The soft tissue periodontium was not affected on either side. There were bony dehiscences on both the graft+ and graft- sides, with slightly but significantly (P=0.038) more bone loss over the mesial root on the graft- side. Bone material density was significantly (P=0.028) greater on the graft+side. Buccal bone apposition was evident surrounding graft particles, and mineralized particulate graft material was present at the apical aspect of the roots on the graft+side. Bone grafting does not prevent dehiscence formation because only a limited amount of new bone is formed, primarily at the more apical aspects of the tooth's roots.

Novel Approach for Lateral Window Sinus Membrane Elevation Using Medical Grade Polyurethane Sponges: Case Report

Introduction: The lateral window approach for maxillary sinus augmentation is a delicate procedure that can be tedious and time consuming. This case report introduces and describes a novel approach to sinus augmentation using dense medical grade polyurethane sponges to elevate the Schneiderian membrane in a simplified manner with reduced risk for sinus membrane perforation.Case Presentation: A 55‐year‐old female patient was referred for evaluation to replace retained tooth #A with a dental implant. Clinical and radiographic assessment indicated a retained deciduous tooth, pneumatization of the maxillary sinus, and a buccal ridge deformity. Tooth #A was extracted, and sinus elevation was performed via a lateral approach by gradually introducing medical grade dense polyurethane sponges. Expansion of the sponges allowed elevation of the sinus membrane from the lateral, inferior, and medial sinus walls. Bovine bone mineral xenograft was placed into the subantral cavity and the buccal deficiency. A resorbable collagen membrane was positioned over the grafted material, covering the lateral osteotomy window. A total lift of 13.7 mm was achieved according to the cone beam computed tomography images obtained, permitting placement of a 4.1 × 10 mm dental implant.Conclusion: This case report describes a novel approach of elevating the sinus membrane by using dense polyurethane sponges to safely and gently elevate the Schneiderian membrane.

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.