Particulate Cancellous Bone And Marrow Research Articles

Use of endosseous implants for dental reconstruction of patients with grafted alveolar clefts

Purpose : The purpose of this study was to investigate the clinical application of endosseous implants placed into grafted alveolar clefts and to evaluate the short-term outcome. Patients and Methods : Nineteen patients (6 males and 13 females; mean age, 17.9 years; range, 9.7 to 33.6 years at first implant surgery), including 11 with unilateral cleft lip and palate, and eight with unilateral cleft lip and alveolus, were studied. All patients except for one who underwent periosteoplasty received grafts of autogenous particulate cancellous bone and marrow (PCBM) obtained from the ilium. After bone bridge formation, orthodontic treatment and preparation for implant placement were performed. Results : A total of 21 implants were placed in the bone-grafted alveoli of the 19 patients. The most frequently used length was 15 mm. In five patients with insufficient alveolar bone height, a chin bone onlay graft was combined with simultaneous implant insertion. The follow-up period ranged from 1 year to almost 3 years after implant placement, and the clinical outcome was excellent in all except one patient. In this short-term study, the overall survival rate was 90.5%. Conclusion : The grafted alveoli were well suited to the placement of endosseous implants, and this treatment was shown to be a viable option for the dental reconstruction of alveolar clefts. However, the interdental alveolar bone height was insufficient for implant installation in a few patients. Further longitudinal studies are required to determine the optimal timing between secondary bone grafting and implant placement.

Histologic and microradiologic comparison of block and particulate cancellous bone and marrow grafts in reconstructed mandibles being considered for dental implant placement

Purpose: Patterns of healing were investigated in mandibles reconstructed with three different techniques to assess their readiness for implant placement. Patients and Methods: The subjects were 10 patients who had undergone mandibular reconstruction with either nonvascularized iliac block bone grafts (group 1; 3 patients), particulate cancellous bone and marrow (PCBM) grafts (group 2; 3 patients) for mandibular discontinuity, or PCBM grafts for mandibular marginal defects (group 3; 4 patients). Six (groups 2 and 3) or 12 months (group 1) after mandibular reconstruction, bone biopsy specimens were obtained for histologic examination with a trephine bur. As controls, bone specimens were obtained from ungrafted mandibles of patients undergoing dental implant placement. Undecalcified specimens were embedded in polyester resin and examined by routine light microscopy and microradiography. Results: The morphology of the specimens from group 1 was similar to that of group 2, but not to that of the control subjects. However, the morphology of specimens from group 3 was generally similar to that of control subjects. Conclusion: These results suggest that mandibular reconstruction with PCBM grafts allows the placement of dental implants sooner than reconstruction with block bone grafts.

Study on the efficacy of biodegradable polyf( l-lactide) mesh for supporting transplanted particulate cancellous bone and marrow: experiment involving subcutaneous implantation in dogs

Poly( l-lactide) (PLLA) mesh sheets, monofilaments and mesh cylinders filled with fresh autogenic particulate cancellous bone and marrow (PCBM) were implanted subcutaneously into the back of 22 adult dogs for 1 yr. Polypropylene (PP) was used as a control. The inflammatory response to PLLA mesh sheets was slight, similar to PP mesh sheets. However, 3 months after implantation, histiocytes and multinucleate giant cells appeared on the surface of the monofilaments of PLLA mesh sheets and gradually increased in number as the monofilaments were degraded and absorbed. Almost no inflammatory cellular infiltration was seen in the tissue around PLLA mesh sheets or between the monofilaments. When a PLLA mesh cylinder filled with PCBM was implanted subcutaneously, the bone formation reached its peak 1 month after implantation, as in the case of a similar PP mesh cylinder, and bone formation was observed along the inner wall of the cylinder. In addition, a vascular net was abundant within the cylinder. The mechanical strength of the test material (PLLA monofilaments) did not change for almost 2 months after implantation, and 80% of its initial strength was retained for 3 months. These observations suggest that a PCBM graft supported by PLLA mesh would be very effective in the reconstruction of damaged maxillofacial bones, since histological tissue reactions associated with biodegradation of the PLLA mesh are mild and the PLLA mesh does not interfere with bone formation of PCBM. It was also found that the PLLA mesh retains its mechanical strength long enough to allow the PCBM transplant to develop sufficient strength to sustain the damaged region.

海綿骨骨髄細片とアパタイトか粒との混合物移植部への人工歯根の適用に関する実験的研究

The purpose of this study was to evaluate the use of hydroxyapatite coated titanium (Ha-Ti) dental implants in graft sites of particulate cancellous bone and marrow (PCBM), with and without hydroxyapatite particles (HAP). In 76 rabbits, defects were created and restored by PCBM with (MIX group) or without (PCBM group) HAP. The implants were supported in position by titanium meshes in the mandible. In one half of the rabbits, the HA-Ti implants were placed immediately (IM group), and in the other half, the implants were placed 90 days after the graft (90D group). The animals were then killed 7, 14, 30, 60 and 90 days after placement of the HA-Ti implants. The healing process was examined histologically, and histomorphometric measurements were made using a computer-based image analyzer to quantify the rate of implant-bone bonding (IBB-ratio). In the IM and MIX groups, the IBB-ratio was lower than in the other groups in the first 30 days after implantation. After 30 days, there was very little difference in the IBB-ratios among the four groups.

合成ヒドロキシアパタイトと自家海綿骨骨髄の混合移植に関する実験的研究 血管密着型ｉｎｃｕｂａｔｉｎｇ ｃｈａｍｂｅｒによる異所性骨形成実験

Hydroxyapatites (HAPs), which are synthetic ceramics (complex calcium phosphates), are very similar to bone and tooth minerals in their complex and have a biocompatibility. Recently, HAPs are used as a bone implant material in variety of situations, eg, surgical reconstruction, augmentation of the facial skeleton, also used to fill acquired and congenital bone defects.Autogenous particulate cancellous bone and marrow (PCBM) had been known to have an active osteogenesis. These implant materials produce desirable effects on regeneration in osseous defects.The aim of this investigation was to ascertain experimentally the biocompatibility, osteoinductive and/or conductive ability of a combined implant material with HAP and autogenous bone in an ectopic situation. Mixed type of materials, porous HAP granules and PCBM (volume ratio, HAP: PCBM=2: 1), were implanted into adult dogs using an vessel attached type incubating chamber which enabled to make the circumstances being free from the influences of recipient site. This chamber was attached to bilateral carotid artery, HAP-PCBM mixed group was implanted on one side and HAP alone group on the other side. Periodical (7, 14, 28, 60, 90 days) histopathological examinations were carried out by light and electron microscopies after implantation.The results were as follows:New bone formation was not observed in HAP alone group throughout the experimental period (90 days). Implanted HAP was encapsulated with fibrous tissue and these tissues were infiltrated with a few inflammatory cells. Macrophages and multinuclear giant cells (MGC) were observed on the HAP-tissue interface (MGC, I supposed to be a fusion cell type of macrophage). HAP resorption occurred by the activities of macrophage and MGC.After 28 days, a newly formed calcified bone matrix surrounded by transplanted trabecular bone chips was observed in HAP·PCBM group. These new bones, initially grew toward the HAP granules, were formed along with the HAP's surface. The osteoconductive ability of HAP in an ectopic site was also confirmed with this results. Under the same experimental conditions, a lamellar bone formation, which was a matured type of bone formation, was confirmed after 90 days.MGC have a different ultramicroscopical features depending on the contact materials. Namely, MGC surrounding a newly formed bone matrix had a ruffled border and clear zone, which were characteristic in osteoclast, but N1GC around HAP or transplanted bone chips had not such organelles.

Evaluation of hydroxylapatite particles in repair of alveolar clefts in dogs

Twelve adult mongrel dogs were used to evaluate the use of hydroxylapatite (HA) in the closure of alveolar clefts. Bilateral alveolar clefts were surgically created in each animal. After healing, they were implanted randomly with either HA or particulate cancellous bone and marrow (PCBM). The results were evaluated clinically, radiographically, and histologically for healing, acceptance of the implant, closure of the fistula, and bony ingrowth. The results show that HA was as successful in closure of the fistulas and re-establishing an intact maxilla as PCBM. Minimal osteoid and bone was interspersed in the HA implant sites. No complications resulted from the HA graft.

下顎部骨移植に関する臨床的研究 ＩＸ 良性腫よう切除後の下顎骨欠損に対する修復・再建

Tumor resections through mandibular preservation as far as possible were carried out for 6 benign tumors composed of 3 ameloblastomas, 2 myxomas and 1 cementifying fibroma. Grafts of 1 particulate cancellous bone and marrow (PCBM), 4 bone chips and 1 block bone taken from the iliac bone without the crest were used for repair or reconstruction of the various types of the defects. All patients were in good clinical courses without postoperative infection. In this paper the results of above bone grafts for mandibular defects which clinically were observed during the past 3 to 6 years were discussed.

Reconstruction of the mandible.

Forty-five patients were evaluated for reconstruction of the mandible. Thirty-four patients had a particulate cancellous bone and marrow (PCM) crib graft placed. Thirty of 34 were successful at the primary operation producing a success rate of 88%. By using secondary procedures all 33 patients repaired to date have been rehabilitated. A dynamic bendable defect bridging plate with cancellous cortical graft (DBDB plate with CCG) was used in 7 patients, 4 of whom had tumor surgery and 3 of whom were operated on after trauma to the anterior mandible. All 7 cases were successfully rehabilitated in achieving a stable, functioning mandibular arch. An osteomyocutaneous flap was planned to reconstruct the anterior mandible in 4 cases; 1 in this group was not reconstructed. The PCM graft has been our first line approach to the mandibular non-union but with experience we are beginning to rely on the DBDB plate with CCG for large bony defects after both trauma and secondarily after tumor surgery. When indicated, the osteomyocutaneous flap has been eminently successful in restoring function and form in the tumor patient.

Autogenous particulate cancellous bone and marrow (PCBM) graft for reconstruction of bony defects in maxillo-facial surgery

Autogenous particulate cancellous bone and marrow (PCBM) graft for reconstruction of bony defects in maxillo-facial surgery