PURPOSE: The aim of this study is to compare the healing response of various Hydroxyapatite(HA) coated dental implants by Ion-Beam Assisted Deposition(IBAD) placed in the surgically created circumferential gap in dogs. MATERIALS AND METHODS: In four mongrel dogs, all mandibular premolars and the first molar were extracted. After an 8weeks healing period, six submerged type implants were placed and the circumferential cylindrical 2mm coronal defects around the implants were made surgically with customized step drills. Groups were divided into six groups : anodized surface, anodized surface with 150nm HA and heat treatment, anodized surface with 300nm HA and heat treatment, anodized surface with 150nm HA and no heat treatment, and anodized surface with 150nm HA, heat treatment and bone graft, anodized surface with bone graft. The dogs were sacrificed following 12 weeks healing period. Specimens were analyzed histologically and histomorphometrically. RESULTS: During the healing period, healing was uneventful and implants were well maintained. Anodized surface with HA coating and 430degrees C heat treatment showed an improved regenerative characteristics. Most of the gaps were filled with newly regenerated bone. The implant surface was covered with bone layer as base for intensive bone formation and remodeling. In case that graft the alloplastic material to the gaps, most of the coronal gaps were filled with newly formed bone and remaining graft particles. The bone-implant contact and bone density parameters showed similar results with the histological findings. The bone graft group presented the best bone-implant contact value which had statistical significance. CONCLUSION: Within the scope of this study, nano-scale HA coated dental implants appeared to have significant effect on the development of new bone formation. And additional bone graft is an effective method in overcoming the gaps around the implants.
Animals ; Bicuspid ; Bone Density ; Dental Implants ; Dogs ; Durapatite ; Hot Temperature ; Mandrillus ; Molar ; Osteogenesis ; Transplants

PURPOSE: This study compared the effects of coating implants with hydroxyapatite (HA) using an ion beam-assisted deposition (IBAD) method prepared with machined, anodized, sandblasted and large-grit acid etched (SLA) surfaces in minipigs, and verified the excellency of coating method with HA using IBAD. MATERIAL AND METHODS: 4 male Minipigs(Prestige World Genetics, Korea), 18 to 24 months old and weighing approximately 35 to 40 kg, were chosen. All premolars and first molars of the maxilla were carefully extracted on each side. The implants were placed on the right side after an 8 week healing period. The implant stability was assessed by resonance frequency analysis (RFA) at the time of placement. 40 implants were divided into 5 groups; machined, anodized, anodized plus IBAD, SLA, and SLA plus IBAD surface implants. 4 weeks after implantation on the right side, the same surface implants were placed on the left side. After 4 weeks of healing, the minipigs were sacrificed and the implants were analyzed by RFA, histology and histometric. RESULTS: RFA showed a mean implant stability quotient (ISQ) of 75.625+/-5.021, 76.125+/- 3.739 ISQ and 77.941+/-2.947 at placement, after 4 weeks healing and after 8 weeks, respectively. Histological analysis of the implants demonstrated newly formed, compact, mature cortical bone with a nearby marrow spaces. HA coating was not separated from the HA coated implant surfaces using IBAD. In particular, the SLA implants coated with HA using IBAD showed better contact osteogenesis. Statistical and histometric analysis showed no significant differences in the bone to implant contact and bone density among 5 tested surfaces. CONCLUSION: We can conclude that rough surface implants coated with HA by IBAD are more biocompatible, and clinical, histological, and histometric analysis showed no differences when compared with the other established implant surfaces in normal bone.
Bicuspid ; Bone Density ; Bone Marrow ; Dental Implants ; Durapatite ; Humans ; Male ; Maxilla ; Molar ; Osseointegration ; Osteogenesis ; Swine, Miniature

PURPOSE: The carrier for the delivery of bone morphogenetic proteins(BMPs) should also serve as a scaffold for new bone growth. In addition, predictable bone formation in terms of the volume and shape should be guaranteed. This study evaluated the ectopic bone formation of recombinant human BMP-2(rhBMP-2) using a micro macroporous biphasic calcium phosphate (MBCP: mixture of betaTCP and HA) block as a carrier in a rat subcutaneous assay model. MATERIALS AND METHODS: Subcutaneous pockets were created on the back of 40 male Sprague-Dawley rats. In the pockets, rhBMP-2/MBCP and MBCP alone were implanted. The blocks were evaluated by histological and histometric parameters after a healing interval of 2 weeks (each 10 rats; MBCP and rhBMP-2/MBCP) or 8 weeks (each 10 rats; MBCP and rhBMP-2/MBCP). RESULTS: The shape and volume of the block was maintained stable over the healing period. No histological bone forming activity was observed in the MBCP alone sites after 2 weeks and there was minimal new bone formation at 8 weeks. In the rhBMP-2/MBCP sites, new bone formation was evident in the macropores of the block. The new bone area at 8 weeks was greater than at 2 weeks. There was a further increase in the quantity of new bone with the more advanced stage of remodeling. CONCLUSIONS: A MBCP block could serve as a carrier system for predictable bone tissue engineering using rhBMPs.
Animals ; Bone and Bones ; Bone Development ; Calcium ; Humans ; Hydroxyapatites ; Male ; Osteogenesis ; Rats ; Rats, Sprague-Dawley ; Subcutaneous Tissue

PURPOSE: The aim of this study was to evaluate the factors affecting healing patterns of surgically created circumferential gap defects around implants in dogs. MATERIALS AND METHODS: In four mongrel dogs, all mandibular premolars were extracted. After 8 weeks of healing periods, implants were submerged. According to the surface treatment, turned surface was designated as a group A and rough surface as a group B. In each dog, surgical defects on the left side were made with a customized tapered step drill and on the right with a customized paralleled drill. Groups were also divided according to the width of the coronal gaps: 1.0mm, 1.5mm, or 2.0mm. The dogs were sacrificed following 8 weeks and the specimens were analyzed histologically and histomorphometrically. RESULTS: During the postoperative period, healing was uneventful and implants were well-maintained. As the size of the coronal gap was increased, the amount of bone-to-implant contact was decreased. The bone healing was greater in rough surface implants compared to the turned ones. About the defect morphology, tapered shape showed much bone healing and direct bone to implant contact even in the smooth surface implants. CONCLUSION: Healing of the circumferential defect around dental implant is influenced by the implant surface, defect width and the morphology of the defect. When using rough surface implants, circumferential gap defects within 2 mm do not need any kinds of regenerative procedures and the healing appeared to be faster in the tapered defect morphology than the paralleled one.
Animals ; Bicuspid ; Dental Implants ; Dogs ; Mandrillus ; Postoperative Period

PURPOSE: In dental clinical fields, various periodontal membranes are currently used for periodontal regeneration. The periodontal membranes are categorized into two basic types: resorbable and non-resorbable. According to the case, clinician select which membrane is used. Comparing different membranes that are generally used in clinic is meaningful. For this purpose, this study evaluates histological effects of various membranes in canine one wall intrabony defect models and it suggest a valuation basis about study model. MATERIAL AND METHOD: The membranes were non-resorbable TefGen Plus(R), resorbable Gore Resolut XT(R) and resorbable Osteoguide(R). One wall intrabony defects were surgically created at the second and the mesial aspect of the fourth mandibular premolars in either right or left jaw quadrants in two dogs. The animals were euthanized 8 weeks post-surgery when block sections of the defect sites were collected and prepared for histological evaluation. RESULTS: 1. While infiltration of inflammatory cells were observed in control, TefGen Plus(R) and Gore Resolut XT(R), it was not observed in Osteoguide(R). 2. TefGen Plus(R) had higher integrity than others and Osteoguide(R) was absorbed with folding shape. Gore Resolut XT(R) was divided everal parts during resorbtion and it was also absorbed from inside. 3. Quantity of new bone and new cementum was not abundant in all membranes. 4. For histologic evaluation of membranes we should consider infiltration of inflammatory, migration of junctional epithelium, integrity of membrane, quantity of new bone and new cementum, connective tissue formation and aspect of resorption. CONCLUSION: This histologic evaluation suggests that Osteoguide(R) provides periodontal regenerative environment with less inflammatory state. It is meangful that this study model suggests a valuation basis about other study model.
Animals ; Bicuspid ; Connective Tissue ; Dental Cementum ; Dogs ; Epithelial Attachment ; Jaw ; Membranes ; Polyglactin 910 ; Regeneration

PURPOSE: Chitosan & chitosan derivative(eg. membrane) have been studied in periodontal regeneration, and recently many studies of chitosan have reported good results. If chitosan's effects on periodontal regeneration are enhanced, we can use chitosan in many clinical and experimental fields. For this purpose, this study reviewed available literatures, evaluated comparable experimental models. MATERIALS AND METHODS: Ten in vivo studies reporting chitosan's effects on periodontal tissue regeneration have been selected by use of the 'Pubmed' and hand searching. RESULTS: 1. In Sprague Dawley rat calvarial defect models, amount of newly formed bone in defects showed significant differences between chitosan/chitosan-carrier/chitosan-membrane groups and control groups. 2. In beagle canine 1-wall intrabony defect models, amount of new cementum and new bone showed significant differences between chitosan/chitosan-membrane groups and control groups. The mean values of the above experimental groups were greater than the control groups. CONCLUSION: The results of this study have demonstrated that periodontal regeneration procedure using chitosan have beneficial effects, which will be substitute for various periodontal regenerative treatment area. One step forward in manufacturing process of chitosan membrane and in use in combination with other effective materials(eg. bone graft material or carrier) may bring us many chances of common use of chitosan in various periodontal area.
Animals ; Chitosan ; Dental Cementum ; Hand ; Membranes ; Rats ; Regeneration ; Transplants

PURPOSE: The purpose of this study was to evaluate the effects of hydroxyapatite containing toothpaste for patients who received periodontal therapy and felt hypersensiptivity. MATERIAL AND METHODS: After application of toothpaste, patients were evaluated for VAS(Visual Analog scale) scores to a cold stimulate on baseline, 1 week, and 4 weeks. VAS scores were analyzed by statistical methods. RESULTS: The results of this study were as follows. 1. VAS scores in control group on baseline, 1 week, 4 weeks were 5.39+/-2.05, 4.75+/-2.00, 4.21+/-1.75. 2. VAS scores in experimental group on baseline, 1 week, 4 weeks were 5.61+/-2.37, 4.81+/-2.46, 4.08+/-2.54. 3. Decrease of VAS scores on hypersensitivity after 1week was 0.64+/-0.49(p<.0001) in control group, 0.80+/-1.65 (p<.0001) in experimental group. 4. Decrease of VAS scores on hypersensitivity after 4weeks was 1.18+/-1.60(p<.0001) in control group, 1.53+/-1.88 (p<.0001) in experimental group. 5. When compared, decrease of VAS scores after 1 week between 2 groups were not statistically different(p=0.2622). 6. When compared, decrease of VAS scores after 4 weeks between 2 groups were not statistically different(p=0.1219). CONCLUSION: It was confirmed that hydroxyapatite containing toothpaste have the similar effect with pre-existing proven dentifrice for relieving teeth hypersensitivity.
Cold Temperature ; Dentifrices ; Durapatite ; Humans ; Hypersensitivity ; Tooth ; Toothpastes

The edentulous posterior maxilla generally provides a limited amount of bone height because of atrophy of the ridge and pneumatization of the maxillary sinus. Maxillary sinus augmentation is one of the surgical techniques for reconstruction of the severely resorbed posterior maxilla. The purpose of this study was to evaluate the survival rate of implants and the long-term changes of graft height after maxillary sinus augmentation by lateral window approach. From September 1996 to July 2004, maxillary sinus augmentation with mixed grafts of autograft, allograft, xenograft and alloplast were performed on 45 patients and 100 implants were placed. We evaluated the survival rate of implants and the changes of BL(bone length)/IL(implant length) according to time using panoramic radiographs. The survival rate of implants was 91.0% for follow-up period. The mean reduction of graft heights was 0.34mm(3.0%) for 6 months and 1.22mm(10.66%) for 3 years after augmentation. The total mean BL/IL was 1.34+/-0.21 during 5 year observation period after augmentation and decreased slightly over time. The result means that graft materials were stable above the implant apex. BL/ILs of 1 stage procedure were significantly decreased at 1-2 year, 3-4 year after augmentation and no statistically significant changes were observed in those of 2 stage procedure. The graft materials of both procedures were stable above the implant apex. No statistically significant changes of BL/IL were observed in the grafts combined with low amount of autogenous bone or without autogenous bone. The graft materials of both groups were stable above the implant apex. The results indicated that the placement of dental implants with maxillary sinus augmentation showed predictable clinical results and the grafts combined with low amount of autogenous bone or without autogenous bone had long-term resistance to resorption in maxillary sinus.
Allografts ; Atrophy ; Autografts ; Dental Implants* ; Follow-Up Studies ; Heterografts ; Humans ; Maxilla ; Maxillary Sinus* ; Survival Rate ; Transplants*

PURPOSE: The purpose of this study was to evaluate the bone regeneration of novel biodegradable amorphous calcium phosphate. MATERIALS AND METHOD: An 8-mm, calvarial, critical-size osteotomy defect was created in each of 20 male Sprague-Dawley rats(weight 250~300g). The animals were divided into two groups of 10 animals each and allowed to heal for 2 weeks(10 rats) or 8 weeks(10 rats). The first group was the control group and the other group was the experimental group which received the novel biodegradable calcium phosphate. RESULTS: The healing of the calvarium in the control group was uneventful. The histologic results showed little bone formation in the control group. The experimental group which received the novel biodegradable calcium phosphate showed a normal wound healing. There were a lot of new bone formation around the biomaterial in 2 weeks. The bone formation increased in 8 weeks when compared to 2 weeks and there was a significant bone increase as well(P<0.01).The novel biodegradable calcium phosphate showed statistical significance when compared to the control group (P<0.05). The novel biodegradable calcium phosphate in 8 weeks showed a significant increase in bone formation when compared to 2 weeks (40.4+/-1.6)(%). The biodegradable calcium phosphate which is made from mixing calcium phosphate glass(CPG), NaCO and NaOH solution, is biocompatible, osteoconductive and has a high potency of bone formation. CONCLUSION: We can conclude that the novel biodegradable calcium phosphate can be used as an efficient bone graft material for its biodegradability and osteoconductivity.
Animals ; Bone Regeneration* ; Calcium* ; Humans ; Male ; Osteogenesis ; Osteotomy ; Rats* ; Rats, Sprague-Dawley ; Skull ; Transplants ; Wound Healing

PURPOSE: Various kinds of biodegradable membranes are currently used in dental clinics. And the frequency and the necessity of their usage are increasing due to their numerous advantages. Therefore it is important to understand the difference of various membranes and histological reaction against implanted membranes. MATERIALS AND METHODS: Biodegradable membranes of Biogide(R), Resolute(R), and Tutodent(R) were cut into small pieces by 1.0x0.5cm. The membranes were implanted 1.5cm apart from each other under the epithelium on the skull of 18 Sprague Dawley rats. The animals were sacrificed at 3, 7, and 14 days after surgical procedure. The specimens were examined by histological analysis. RESULTS: 1. Early period after implantation of the membranes showed connective tissues surrounding membranes and there were a few inflammatory cells present. 2. In Biogide(R) and Tutodent(R) specimens, inflammatory cells and surrounding tissues were shown to infiltrate from outside with slight density difference inside. In Resolute(R) specimens, membranes were fragmented. Inflammatory cells and connective tissues were also observed inside. 3. In Resolute(R) specimen, giant cells were present which implicates that foreign body reaction has occurred. 4. Biogide(R) had lower integrity than other membranes and is not enough to be used alone in defect area. However, Resolute(R) had superior firmness than others. Tutodent(R) had middle level of integrity. CONCLUSION: This experimental model enabled to observe early inflammatory reactions and morphological changes of materials and can be used to develop and evaluate the efficacy of biodegradable membranes. Duplication of standardized human oral environment will be required in future experiments.
Animals ; Connective Tissue ; Dental Clinics ; Epithelium ; Foreign-Body Reaction ; Giant Cells ; Humans ; Membranes* ; Models, Theoretical ; Rats* ; Rats, Sprague-Dawley ; Skull