Papers by Author: Byung Ock Kim

Abstract: The purpose of this study is to figure out the effect of maintaining period of PTFE membrane used in GBR with autogeonous bone, heterogeneous bone and synthetic bone on bone formation on rabbits' cranial defect. Eight adult New Zealand white rabbits were used in this study. Four defects were surgically made in their calvaria. Using a trephine bur, 4 'through and through' defects were created and classified into 4 groups, which were consisted of control (no graft), experimental group 1 (autogeonous bone) and experimental group 2 (deproteinized bovine bone: OCS-B®; NIBEC, Korea), experimental group 3 (synthetic bone: MBCP; Biomatlante, France). The defects were covered with PTFE membrane (Cytoplast®, Innova, Canada). Membranes were removed after 1, 2, 4 and 8 weeks post-GBR in each 2 rabbits. And then, all rabbits were sacrificed; specimens were taken and observed histologically..: After removing the membranes after 1 week of the experiment, bone formation was not evident in a control group but the area was replaced with only loose fibrous connective tissue. In group 1(autogeonous bone), thin bone formation and infiltration of connective tissue on the superficial layer were observed. Initial bone formation and infiltration of fibrous connective tissue were evident in group 2(deprotenized bovine bone) and 3(synthetic bone). When the membranes were removed after 2 weeks of the experiment, bridge shaped bone formation was shown in control group but mostly connective tissue took place. More increased bone thickness was evident in group 1 and increased bone formation than first week was shown in group 2 and 3. When the membranes were removed after 4 weeks of the experiment, 2/3 of normal bone thickness was formed in control group still with infiltration of connective tissue. In group 1, regular bone formation with normal bone thickness was shown and in group 2 and 3, similar bone thickness to the normal was evident. After the removal of the membranes in 8 weeks, bone thickness formed in control group was more increased than 4th week, but could not reach normal bone thickness. In group 1, normal bone thickness was formed and similar bone thickness to that of the normal was observed in group 2 and 3. Within the limited study, when performing the GBR procedure, at least 4-week period of the membrane retention is required, and more retention time of the xenograft or synthetic bone is needed than that of autogenous bone for better bone regeneration.

Abstract: The purpose of this study is to evaluate the new bone formation of sinus augmentation with using ICB (Irradiated Cancellous Bone & Marrow; Rockey Mountain Tissue Bank, Denver, Co) and MBCP (Micro-Macroporous Biphasic Calcium Phosphate;Biomatlante, France). Study population consisted of 4 patients with maxillary posterior edentulous dentition and ridge heights were less than 5 mm. ICB (Rockey Mountain Tissue Bank, Denver, Co) and MBCP (Biomatlante, France) is mixed with 50: 50. After 6 months, the bone biopsies were done with 2mm trephine bur from lateral window opening. Mean new bone formations were 26.84 %, the residual grafts were 4.92 and soft tissues were 67.98 %. The small number of biopsies did not permit analysis of statistical significance. The variability of individual patient factors do not permit definitive conclusions. The mixtures of ICB & MBCP were superior or comparable to another various bone alternative materials in new bone formation of sinus floor elevation.

Abstract: This study evaluated the histology results of surgically created bone cavities in the calvaria of rabbits that were subsequently filled with a HA/ß-TCP composite powder developed in Korea (Dentium, Korea). Ten young adult rabbits were used. Four defects were surgically produced in the calvaria of each rabbit. These defects were classified into 4 groups: the control group, no graft materials; experimental group I, normal saline + graft materials; experimental group II, venous blood + graft materials; and experimental group III, graft materials only. The defects were randomly filled with the graft materials. The rabbits were sacrificed with at 1-, 2-, 4-, 6- and 8- weeks after surgery. The histology specimens were prepared using the general method with H & E staining at a 6 ㎛ thickness. Histologically, the degree of new bone formation was similar in all experimental groups. However, for experimental group II, many cells had gathered around the graft materials 1-week after surgery, and new bone formed slightly faster and than in the other groups. No bone formation was observed in the control group. Based on histology findings, the new HA/ß- TCP composite powders appeared to act as a scaffolding material for the regeneration of osseous defects.

Abstract: This study evaluated the efficacy of periodontal tissue regeneration using guided tissue regeneration (GTR) with a mixture of tooth ash and plaster as a bone substitute material in the treatment of class II furcation defects in dogs. GTR was performed at the site of a surgically formed mandibular premolar bifurcation area in dogs. Four adult dogs were used in the animal study. The animals were in a good periodontal state without any systemic disease. A resorbable membrane (Bio-Gide®, Swiss) and bone graft material using a mixture of tooth ash and plaster were used to examine the biological activity. The defect in the control group was filled a Bio-Gide® only. For the experimental group, the defects were filled with a mixture of tooth ash and plaster and covered by a Bio-Gide®. Oral rinsing with 0.12% chlorhexidine was performed twice a day for 2 weeks. In control group, new bone formation was observed adjacent to the preexisting bone. Soft tissue ingrowth was also noted. In experimental group, new lamellar type trabecular bone formation as well as centum and PDL regeneration was observed in the base of the infrabony pocket. More bone regeneration would be expected when GTR is performed using a mixture of human tooth-ash and plaster of Paris as a bone graft material.