Sinus Bone Graft Research Articles

Reliability of Short Implants in Oral Rehabilitation

Implant prostheses are often used to restore partially or completely edentulous patients but limited bone height, especially in the posterior mandible, may restrict the use of dental implants. Short implants (i.e. x ≤ 10 mm) may be selected in these situations. They have several advantages: 1 - restricting the need for sophisticated and expensive surgical procedures like sinus lifting, bone grafting and mandibular nerve transposition, 2 - placing short-span dentures and 3 - avoiding cantilevers in the posterior sextants. The limited surface area of SIs, conversely, can be a potential disadvantage as it has less resistance to occlusal forces. Since no report is available on a new type of implants, a retrospective study was performed. A total of 148 short (i.e x ≤ 10 mm) two-piece implants (FMD srl, Rome, Italy) were inserted, 91 in female and 57 in males. The median age was 58 ± 12 (min-max 25–80 years). Implants were inserted 68 in the maxilla and 80 in the mandible. One implant was lost, survival rate = 98.52%. Among the studies variables post-extractive implants on single tooth rehabilitations (p=0.043) was the only significant variable. Then peri-implant bone resorption (i.e. delta IAJ) was used to investigate SCR. Among the remaining 147 implants, 18 fixtures have a crestal bone resorption greater than 1.5 mm (SCR = 87.75). Statistical analysis demonstrated that only diabetes has a negative impact on peri-implant crestal bone resorption (p=0.016). In conclusion FMD implants are reliable devices for oral rehabilitation with a very high SCR and SVR.

A comparative study of the effectiveness of sinus bone grafting with recombinant human bone morphogenetic protein 2–coated tricalcium phosphate and platelet-rich fibrin–mixed tricalcium phosphate in rabbits

The objective of this histologic study was to evaluate platelet-rich fibrin (PRF)-mixed tricalcium phosphate (TCP) and recombinant human bone morphogenic protein 2 (rhBMP-2)-coated TCP in their potential to enhance bone regeneration in sinus elevation in rabbits as well as in their inflammatory features. Bilateral round-shaped defects (diameter 8.0 mm) were formed in the maxillary anterior sinus walls of 36 New Zealand white rabbits. The defects were grafted with TCP only (control group), with rhBMP-2-coated TCP (experimental group A) and with PRF-mixed TCP (experimental group B). Each group included 12 rabbits. The animals were killed at 3 days, 1 week, 2 weeks, 4 weeks, 6 weeks, and 8 weeks. The specimens underwent decalcification and were stained for histologic analysis. There were no significant differences in inflammatory features among the groups at 3 days or the first week after operation. In a histomorphometric analysis, the new bone formation ratio showed significant differentiation between groups A and B. The TCP-only control group showed a relatively lower bone formation ratio rather than the experimental groups. The PRF-mixed TCP group showed a larger bone formation area, compared with both the control group and group A. In the results of the histologic evaluation (hematoxylin-eosin, Masson trichrome stain), the experimental groups A and B showed rapid bone formation, remodeling, and calcification in the second week. Moreover, there was a significant difference between those experimental groups and the control group in the new bone formation area at the fourth, sixth, and eighth weeks. The PRF-mixed TCP showed more rapid bone healing than the rhBMP-2-coated TCP or the TCP-only control.

Study on the position of the posterior superior alveolar artery in relation to the performance of the maxillary sinus bone graft procedure in a Korean population

J Korean Assoc Oral Maxillofac Surg 2012;38:71-7) Objectives: This study sought to investigate the positioning of the posterior superior alveolar artery in relation to the performance of the maxillary sinus bone graft procedure in a Korean population. Materials and Methods: We identified the position of the posterior superior alveolar artery relative to 93 maxillary sinuses in 58 patients and determined the distance from the inferior border of the artery in the premolar and molar areas to the alveolar ridge and sinus floor. Results: The mean distance from the alveolar ridge to the posterior superior alveolar artery in the dentate group (20.62±3.05 mm in the premolar region, 17.50±2.84 mm in the molar region) was greater than as compared to the edentulous group (18.83±2.79 mm in the premolar region, 15.50±1.64 mm in the molar region), and this difference was statistically significant ( P 0.05) between the mean distance from the sinus floor to the posterior superior alveolar artery in the dentate group (8.21±2.79 mm in the premolar region, 7.52±2.07 mm in the molar region) or in the edentulous group (7.75±3.31 mm in the premolar region, 7.97±2.31 mm in the molar region). Conclusion: Prior to surgery, it is important to evaluate the position of the posterior superior maxillary artery by using computed tomography scans. The premolar area is safer than the molar area for performing the maxillary sinus bone graft without bleeding.

Retrospective Study of Bone Resorption after Maxillary Sinus Bone Graft

Purpose: This research sought to determine the resorption rate of bone grafted to the maxillary sinus according to the grafted material’s type, patient’s age, systemic disease, implant size, site of implant placement, and residual ridge height. Materials and Methods: This research targeted 24 patients who had immediate Osstem ® implant (US Plus ® ) placement after bone graft. The panorama was taken before the surgery, after the surgery, and 6 months after the surgery. Vertical height change and resorption rate of the grafted bone were measured with the same X-rays and compared. The influence of the following factors on the grafted bone material’s resorption rate was evaluated: grafted material type, patient’s age, systemic disease, implant size, site of implant placement, and residual ridge height. Results: Patients in their 40s had 34.0±21.1% resorption rate, which was significantly higher compared to the other age groups (P＜0.05). There was no significant relationship between systemic disease and grafted bone resorption. There was no significant relationship between implant size (diameter, length) and grafted bone resorption. There was no significant relationship between the site of implant placement and grafted bone resorption. The ramal bone-grafted site was significantly more resorbed than the ramal bone/Bio-Oss ® -grafted site, maxillary tuberosity bone/Bio-Oss ® -grafted site, and ramal bone/maxillary tuberosity bone/Bio-Oss ® -grafted site (P＜0.05). There was no significant difference in the grafted bone resorption rate in the sinus between more than 4 mm and less than 4 mm residual ridge heights. After an average of 6 months, a second surgery was done; given an average follow-up of 1.9 years, the success rate and survival rate of the implant were 96.9% and 98.4%, respectively. Conclusion: These results indicate that the bone resorption rate of grafted bone among patients in their 40s is higher compared to patients in their 50s and over, and that only autogenous bone (ramus) shows higher resorption rate than the mixed graft of autogenous bone and xenogenous graft (Bio-oss) after maxillary sinus graft.

Effects of Platelet‐Rich Plasma on Sinus Bone Graft: Meta‐Analysis

This meta-analysis investigates the effects of platelet-rich plasma (PRP) on the sinus bone graft. PubMed, the Cochrane Library, and EMBASE were searched in January 2010. Of 61 articles searched, eight controlled clinical trials, which included a total of 352 sinus bone graft cases in 191 patients, were included in the final analysis. In the fixed-effects meta-analysis, the implant survival was not significantly different between two groups in the patient-based data of four studies (relative risk [RR]: 1.02; 95% confidence interval [CI]: 0.97 to 1.08) and in the implant-based data of three studies (RR: 1.02; 95% CI: 0.99 to 1.04). The bone formation was significantly greater in the intervention group in the random-effects model (standardized mean difference [SMD]: 1.30; 95% CI: 0.21 to 2.39) in five studies with significant heterogeneity (I(2) = 76.2%). The bone-to-implant contact was not significantly different between two groups in the random-effects model (SMD: 1.02; 95% CI: -1.65 to 3.70) in two studies with significant heterogeneity (I(2) = 82.4%). The present study indicates that there was sufficient evidence to support the use of PRP for bone formation on a sinus bone graft, whereas there was no significant effect on the implant survival and bone-to-implant contact.

A Wide-Body Implant as an Alternative for Sinus Lift or Bone Grafting

The aim was to evaluate the outcome of a short wide-body implant in the atrophic posterior jaw without a grafting procedure. Patients treated with a tapered wide-body implant measuring 8 to 9 mm in width and 7 to 9 mm in length (Max implant; Southern Implants, Irene, South Africa) were recalled to scrutinize implant survival. Preoperative cone beam computed tomography images were analyzed to measure bone height in reference to the mandibular canal and sinus floor. There were 57 implants inserted in 18 men and 24 women after a 2-stage procedure and delayed loading. The mean follow-up was 15 months (SD, 10; range, 1-32 months), with 63.2% of the implants having at least 1 year of follow-up and 26.3% having at least 2 years' follow-up. Forty-six implants were inserted in the posterior maxilla and eleven in the mandible. Fifteen were placed in an extraction socket and forty-two in healed bone. Thirteen implants were supporting a single crown. Two implants failed, resulting in a survival rate of 96.5%, with rates of 90.9% and 97.8% for mandible and maxilla, respectively. This was not affected by gender, jaw, immediate or delayed placement, implant diameter and length, or the use of a bone substitute. The mean preoperative bone height was 7.21 mm in maxilla and 8.76 mm in mandible. In 41 cases implant length surpassed available bone height. Despite the compromised bone condition and height, the survival rate of 96.5% is comparable to normal implants and, therefore, placing a wide-body implant may be an alternative to avoid grafting procedures. This is probably related to the enlarged implant surface area and the good primary stability.

Multiple window access antrostomy in maxillary sinus grafting. Presentation of a clinical serie of 10 cases and literature review

Objectives: A variation on the usual maxillary sinus grafting technique and its results are presented, using a more conservative approach that provides better conditions for applying the graft in complicated situations. Material and Methods: Ten case reports are presented in which the multiple access technique was used due to the existence of large maxillary sinuses, where a wide surgical approach was needed because several implants were to be installed or cases in which sinus bone graft was part of a more extensive reconstructive prodedure. Results: All the implants that were placed after using this technique were correctly integrated and it was possible to proceed to the prosthesis stage without any problems. Conclusions: This modified technique of sinus floor bone grafting can have a beneficial effect with a lower risk of perforations, better preservation of vascularisation in the area and improved integration and stability of the implants and bone graft, specially where wider surgical access is required.

Evaluation of the feasibility of bony window repositioning without using a barrier membrane in sinus lateral approach

Introduction: In the lateral window approach for a maxillary sinus bone graft, there has been considerable controversy regarding the placement of a barrier membrane over the osteotomy site. In particular, when there is no damage to the Schneiderian membrane, clinicians should decide whether to use a barrier membrane or not, considering the benefits and costs. This study presents the clinical cases to demonstrate that only repositioning the detached window can lead to satisfactory bony healing of the grafted material without using a barrier membrane in the lateral approach for a maxillary sinus bone graft. Materials and Methods: Five consecutive patients were treated with the same surgical procedures. After performing the antrostomy on the lateral maxillary wall using a round carbide bur and diamond bur, the bony window was detached by a gentle levering action. After confirming no perforation of the Schneiderian membrane, the grafting procedure was carried out the detached window of the lateral maxillary wall was repositioned over the grafted material without using a barrier membrane. A gross examination was carried out at the postoperative 6 month re-entry, and the the preoperative and postoperative dental computed tomography (CT) at re-entry were compared. Results: All the procedures in the 5 patients went on to uneventful healing with no complications associated with the bone graft. Satisfactory bone regeneration without the interference of fibrous tissue on the gap between the repositioned window and lateral wall of the maxillary sinus was observed in the postoperative 6 month re-entry. The CT findings at re-entry revealed the, reconstruction of the external cortical plate including repositioned bony window. In addition, the loss of the discontinuity of the lateral maxillary wall was confirmed. Conclusion: This preliminary report showed that the detached window, which was just repositioned on the grafted material, could function as a barrier membrane in the lateral approach for a maxillary sinus bone graft. Therefore additional morphometric and histologic studies will be needed.

Comparison of clinical outcomes of sinus bone graft with simultaneous implant placement: 4-month and 6-month final prosthetic loading

The aim of this study was to compare the survival rate and surrounding tissue condition of sinus bone grafts with simultaneous implant placement between 4-month and 6-month occlusal loading after implantation. Twenty-seven patients (61 implants) who were treated with sinus bone grafts (sinus lateral approach) and simultaneous Osstem GS II implant placement from July 2007 to June 2008 were included in this study. Of these patients, 14 (31 implants) were in the 4-month loading group, and 13 (30 implants) were in the 6-month loading group. We investigated the implantation type (submerged or nonsubmerged), sinus membrane perforation, type of prosthesis, opposed tooth type, primary and secondary stability of implants, and crestal bone loss around implant and surrounding tissue conditions. The amounts of crestal bone-loss at the final recall time (12.56 ± 5.95 mo after loading) of the 4-month and 6-month loading groups were 0.19 ± 0.33 mm and 0.39 ± 0.86 mm, respectively. However, the difference between groups was not statistically significant (P = .211). The width of keratinized mucosa, gingival index, plaque index, and pocket depth of the 4-month and 6-month loading groups were 2.50 ± 1.69 mm and 1.73 ± 1.40 mm (P = .081), 0.72 ± 0.83 and 0.59 ± 0.69 (P = .671), 1.11 ± 0.96 and 0.76 ± 0.79 (P = .226), 3.56 ± 0.98 mm and 3.65 ± 1.06 mm (P = .758), respectively. The primary stabilities of implants in the 4-month and 6-month loading groups were 61.96 ± 12.84 and 56.06 ± 15.55 (P = .120), and the secondary stabilities were 71.85 ± 6.80 and 66.51 ± 11.28 (P = .026), respectively. The secondary stability of the 4-month group was significantly higher than that of the 6-month group. There was no statistical difference (P > .05) between the 4-month and 6-month loading groups regarding the implantation type (submerged or nonsubmerged), sinus membrane perforation, type of prosthesis, or opposed tooth type. In the 4-month and 6-month groups, all of the implants survived until the final recall time. For the cases in which the residual bone was >3 mm and primary implant stability could be obtained, we conclude that loading is possible 4 months after the sinus bone graft and simultaneous implant placement.

I Conferencia Nacional de Consenso sobre el Injerto Óseo del Seno Maxilar

Objective The objectives of the first Spanish Consensus Conference on Sinus Bone Graft were trying to reach agreements points on the major controversies of this technique, and translate them in a summary document. Material and method During the 17th and 18th of October of 2008 took place in Oviedo (Spain) the Conference, sponsored by the Spanish Society of Oral and Maxillofacial Surgery. There, 50 national and international speakers reviewed in 6 workshops the major controversies of sinus bone grafts. Following the conferences, the moderators proposed the main conclusions of each workshop and opened a round of discussion where all attendees participated. Results This document and its conclusions emanate from the presentations made by the speakers and the discussions and agreements of each workshop. Both have been approved after several corrections by all authors before being submitted for publication. They have also obtained the official scientific recognition of the Spanish Society of Oral and Maxillofacial Surgery and should serve as a basis for future scientific studies and meetings. Conclusions The main objective when we perform a sinus bone graft is vital bone formation in the maxillary sinus, to achieve long-term survival of the implants after prosthetic loading. To do this, the technique and sequence of treatment should aim to achieve predictable and stable results over time, although this involves a longer waiting time. The initial implant stability is the key factor for osseointegration and should be the main criterion to indicate simultaneous or delayed implants in the maxillary sinus.

Sinus bone graft using new alloplastic bone graft material (Osteon)—II: clinical evaluation

The objective of this study was to clinically evaluate the use of Osteon as a sinus bone graft material and to measure the loss of sinus bone graft volume and marginal bone loss around the implants. Thirty-two implants were placed in 16 patients after maxillary sinus bone grafting. In 7 patients, maxillary sinus bone graft was performed first and 15 implants were placed after 4 months; in 9 patients, 17 implants were placed simultaneously with maxillary sinus bone grafting. Based on medical records and radiographs, intraoperative and postoperative complications were examined, and at 1 year after the placement of the upper fixture, the success rate of implants, peri-implant soft tissue condition, and the marginal bone loss were evaluated. Additionally, the sinus bone graft volume loss was evaluated by comparing the residual alveolar bone height of the preoperative maxillary sinus floor with that immediately after the operation and after 1 year. Regarding intraoperative complications, perforation of the maxillary sinus membrane occurred in 6 cases (37.5%), and after surgery maxillary sinusitis developed in 2 cases. During the healing period, 1 implant failed in osseointegration. At the last follow-up observation, none of cases showed marginal bone loss of >1 mm and a 96.9% success rate was seen. The follow-up observation period after placement of the superstructure was 12-30 months (average 15). Between the simultaneous placement group and the delayed placement group, marginal bone loss showed no statistically significant difference (P = .455). In the entire patient group, the volume of sinus bone graft loss did not correlate with marginal bone loss (P = .568). Preoperative alveolar bone height was 0.8-8.8 mm (mean 4.64), postoperative alveolar bone height was 12-21.8 mm (mean 17.67), and the alveolar bone height 1 year after the operation was 11.2-20.8 mm (mean 16.78). Between the group with perforation of the maxillary sinus membrane and the group without, no difference in marginal bone loss was observed (P = .628). Additionally, no difference in the volume of sinus bone graft resorption between the two groups was observed (P = .970). It was concluded that Osteon is suitable for use in sinus graft application.

Effect of bovine bone (Bio-Oss®) and platelet rich plasma, platelet poor plasma on sinus bone graft in rabbit

Maxillary sinus lift and bone graft are used to reconstruct atrophic maxilla molar area for endosseous dental implants. Many different grafting materials and techniques can be used for maxillary sinus bone graft.Bio-Oss® has been proposed as bone substitute and successfully utilized as osteoconductive filler. Platelet rich plasma (PRP) is an autologous material with many growth factors, such as PDGF, TGF-β, IGF, VEGF, facilitating bone healing process. And Platelet poor plasma (PPP) is the by-product in procedure of producing PRP.Six rabbits were used as experimental animal. Both maxillary sinus were grafted with Bio-Oss® and PRP, and Bio-Oss® and PPP. Rabbits were sacrificed at 4, 8 and 12 weeks. The grafting sites were evaluated by histomorphometric analysis.As a result, using PRP showed excellent bone formation in the early stage, but no further significant effect after that. In late stage, the ability of bone formation of using PRP was even worse than using PPP. The further studies need to be considered in this case.

Alternative Applications of Guided Surgery: Precise Outlining of the Lateral Window in Antral Sinus Bone Grafting

Computed tomography (CT) and the application of CT-based guided implant surgery allow clinicians to provide enhanced precision and accuracy in implant surgery. Because of the difficulty in transferring a patient's often complex anatomic sinus configurations, as viewed on a preoperative CT scan, into precise osteotomy cuts at antral bone graft surgery, a prototype cutting guide was developed. The surgical guide was developed through the use of CT imaging, SimPlant module Oral and Maxillofacial Surgery computer software (Materialise Dental, Glen Burnie, MD), and the stereolithographic process to precisely position the lateral window, facilitating Schneiderian membrane elevation. This report demonstrates the step-by-step method to perform precise guided sinus window preparation using computer software and a stereolithographically generated surgical guide.

Maxillary Tuberosity Block Bone Graft: Innovative Technique and Case Report

Hard tissue defects resulting from trauma, infection, or tooth loss often lead to an unfavorable anatomy of maxillary and mandibular alveolar processes that become not suitable for implant therapy without bone grafting. The goal of pre-implant bone augmentation of the deficient alveolar ridge is reconstruction of the proper alveolar anatomy through the techniques of socket preservation, horizontal and vertical ridge augmentation, sinus bone grafting, and others. A variety of bone grafts and bone grafting materials have been used in the last 30 years for augmentation of deficient alveolar ridge for the purpose of implant treatment of partially and completely edentulous patients. Bone grafting options include autogenous, allogeneic, xenogeneic, synthetic bone, and combination of above. Autogenous bone grafts are considered "the gold standard" due to their compatibility and osteogenic potentials to form the new bone by processes of osteogenesis, osteoinduction, and osteoconduction. A particulate and block autogenous bone has been used for correction of alveolar ridge deficiency. Extraoral sites of autogenous block grafts include: ilium, calvarium, tibia, rib, and others. Intraoral sites of autogenous block grafts include symphysis and retromolar-ramus areas. In the clinical practice, a maxillary tuberosity bone graft has often been used as a particulate graft for augmentation of deficient alveolar ridge or maxillary sinus prior to or simultaneously with implant insertion. This article presents an innovative technique and reports a case of the maxillary tuberosity block bone graft that can be used to correct moderate to severe localized defects of the alveolar process prior to implant placement.

Histomorphometric Evaluation of Mineralized Cancellous Allograft in the Maxillary Sinus Augmentation: A 4 Case Report

The aim of this article is to report the histomorphometric analysis and clinical study of mineralized cancellous bone allografts in maxillary sinus augmentation procedures in 4 cases. Sinus bone augmentation, using a piezoelectric device and mineralized cancellous allografts, was performed in 3 patients. After an average of about 8 months of healing, a trephine core sample was gained from the lateral windows area for histomorphometric analysis. The mineralized cancellous allografts demonstrated normal healing of hard tissues. Upon reentry for dental implant placement or secondary surgery, the graft materials showed hard bony structures within the maxillary sinus. Histomorphometric analysis of the cores revealed an average vital new bone content of 17.88%. Mineralized cancellous allografts showed favorable bone regeneration histologically and was clinically useful in augmenting bone volume for implant placement in the sinus bone graft.

Erbium, chromium:yttrium–scandium–gallium–garnet laser-assisted sinus graft procedure

The possibility of using lasers in the field of dentistry has been a subject of investigation. There are few reports that any laser systems have been used for bony window osteotomy by direct sinus grafting. In this study, erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser of various laser systems was used for 12 sinus bone grafts in ten patients, and the efficiency of the laser was evaluated according to the osteotomy time and the rate of sinus membrane perforation in the clinical results; the mechanism is described. Eight of the 12 procedures were performed by direct sinus grafting with the Er,Cr:YSGG laser without membrane perforation (perforation ratio 33.3%). Operating time for bony window osteotomy with laser alone was 2-7 minutes [3 min 24 s on average; 3.4 +/- 1.4 min (mean +/- standard deviation)], and all the implants placed immediately were successful.

Evaluation of sinus bone resorption and marginal bone loss after sinus bone grafting and implant placement

The objective of this study was to evaluate the sinus bone graft resorption and marginal bone loss around the implants when allograft and xenograft are used. Sinus bone grafting and implant placement (Osstem, Korea) were performed on 28 patients from September 2003 to January 2006. In group I, a total of 49 implants were placed in 23 maxillary sinus areas of 16 patients together with bone graft using xenograft (Bio-Oss) and a minimal amount of autogenous bone. In group II, 24 implants were placed in 13 maxillary sinus areas of 12 patients together with bone graft using a minimal amount of autogenous bone and equal amounts of allograft (Regenaform) and Bio-Oss in group II. Early osseointegration failures of 3 implants in 3 patients (group I: 1 patient, 1 implant; group II: 2 patients, 2 implants) were observed, and revisions were performed for these 3 implant sites, followed by complete prosthodontic treatments. The average height of the remaining alveolar bone before the surgery, immediately after the surgery, and 1 year after the surgery was 4.9 mm, 19.0 mm, and 17.2 mm, respectively, in group I. In group II, the average height of the remaining alveolar bone was 4.0 mm, 19.2 mm, and 17.8 mm before the surgery, immediately after the surgery, and 1 year after the surgery, respectively. The average marginal bone loss 1 year after prosthodontic loading and after 20.8 months' follow-up was 0.6 mm and 0.7 mm, respectively, in group I. A 93.9% success rate was observed for group I, with 3 implants showing bone resorption of >1.5 mm within 1 year of loading. For group II, the average marginal bone loss 1 year after prosthodontic loading and after 19.7 months' follow-up was 0.7 mm and 1.0 mm, respectively. An 83.3% success rate was observed for group II, with 4 implants showing bone resorption of >1.5 mm within 1 year of loading. Based on the observations in this study, it was concluded that mixed grafting with demineralized bone matrix for maxillary sinus bone grafting has no significant short-term merit regarding bone healing and stability of implants compared with anorganic bovine bone alone.

Fungal infection as a complication of sinus bone grafting and implants: a case report

Sinus bone grafts have been used successfully to augment atrophic posterior maxilla for dental implant placement. Even though sinus bone grafting is generally considered to be a safe surgical procedure, postoperative maxillary sinus infections can occur and therefore need to be considered. Bacteria, as well as viruses and fungi, have been identified as causative agents. Because fungal infection of the maxillary sinus after sinus bone grafting is not well known, we report a case of a middle-aged male patient along with the clinical, radiographic, and histologic findings. The patient was referred from his private dentist because of failed sinus bone grafting and osseointegration of implants. The surgical approach to the sinus yielded a friable mass of brownish-red material from the sinus. Review of pathology slides revealed a noninvasive hyphal mass caused by Aspergillus and polypous mucosa. After surgical removal of the mycotic masses, sinus bone grafting, using allograft, was performed. Bone formation after the healing period was favorable and dental implants were placed. There was no recurrence of fungal sinusitis.

Analysis of the healing process in sinus bone grafting using various grafting materials

The purpose of this study was to compare differences in the healing process in the sinus bone grafting using various grafting materials. Maxillary sinus bone grafts were divided into 4 groups according to the graft material used: group I, a mixture of autogenous bone and BioOss (Osteohealth Co., Shirley, NY); group II, a mixture of BioOss and Orthoblast II (Greencross; Isotis); group III, BioOss only; and group IV, synthetic bone, Osteon (Genoss, Korea), only. To evaluate the healing status of the graft surgery, bone specimens were collected from the lateral sinus using a 2.0-mm trephine bur at 4 and 6 months after surgery. Histology of the bone specimens was prepared, and the percentage of newly formed bone fraction, lamellar bone/woven bone ratio (LB/WB), and newly formed bone/graft material ratio (NB/GM) were measured to indicate the suitability of the materials and the healing of the grafts. The LB/WB ratio and NB/GM ratio were markedly increased at 6 months compared with the values at 4 months. It was observed that good bone healing was achieved even for grafts of xenogeneic bone only or synthetic bone only. Cases grafted with a mixture of allogeneic and xenogeneic bone showed no great advantage regarding bone healing. The results indicated that grafts of xenogeneic or synthetic bone can be effective for sinus bone grafting.

Controlling Systematic Perioperative Anaerobic Contamination During Sinus-Lift Procedures by Using Metronidazole: An Innovative Approach

Analysis of tomodensitometric controls following sinus grafts clearly demonstrates a quite systematic lack of homogeneity. Sinus contamination by anaerobic bacteria seems almost unavoidable during bone graft surgery, and this problem may jeopardize the healing process. The aim of this study was to characterize in a systematic way the nonhomogeneities observed at 1, 2, or 3 months postsurgery within allogenous sinus grafts, and to assess the possible influence of a 0.5% sterile solution of metronidazole incorporated in the sinus bone graft. This clinical study was conducted on 72 patients treated with single or bilateral sinus-lifts: 94 sinus elevations performed with freeze-dried bone allograft (Phoenix, TBF, Mions, France), with (test group) or without (control group) metronidazole. In the test group, each bone graft was hydrated with 2 mL of a 0.5% metronidazole solution, i.e., only 10 mg of metronidazole. All the patients went through a first presurgical computerized tomography (CT)-scan followed by a second scan performed at 1, 2, or 3 months postsurgery (which was used as the preimplant reference scan). For 11 patients, 2 postsurgical CT-scans were performed respectively at 10 days and 2 months. Using an arbitrary gray scale (Arbitrary Densitometric Unit) which functions according to the Hounsfield unit principle, the degree of radiographic homogeneity of the grafts was established. Density scattering provides some information on the homogeneity or nonhomogeneity of the bone graft. The 12 grafts performed without metronidazole show significant nonhomogeneities at 1, 2, or 3 months. Moreover, when a CT-scan is performed during the first postoperative days (at 10 days), the presence of air bubbles in the graft is confirmed. The tomodensitometric aspects of all grafts treated with metronidazole in this series are absolutely identical: they show a high degree of homogeneity. Sixty-three cases (76.8%) are homogeneous, and 19 cases (23.2%) are significantly homogeneous. The time at which the control scan is performed (10 days, 1, 2, or 3 months) does not seem to influence significantly the degree of homogeneity assessed. In the control group, some inflammatory events associated with facial oedema were observed in 25% of the cases. In the test group, no such event was recorded for the 82 sinus-lifts treated with metronidazole. A possible correlation may exist between the occurrence of non homogeneities within the bone grafts and the anaerobic bacterial contamination. The local use of a very small quantity of metronidazole (equivalent to only 1/20 of a common 200 mg oral tablet) could provide more security when performing sinus-lift procedures and an improved quality of the graft. This protocol should not be considered as an antibiotherapy, but only as way to limit the initial contamination of bone graft.