The evaluation of healing patterns in surgically created circumferential gap defects around dental implants according to implant surface, defect width and defect morphology / 대한치주과학회지

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.

Effect of Hydroxyapatite containing dentifrice on teeth hypersensitivity after periodontal therapy / 대한치주과학회지

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.

Study of chitosan's effects on periodontal tissue regeneration: a meta-analysis of the histomorphometry / 대한치주과학회지

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.

Histologic evaluation of various membranes on periodontal tissue regeneration of 1-wall intrabony defects in dogs / 대한치주과학회지

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.

rhBMP-2 using biphasic calcium phosphate block as a carrier induces new bone formation in a rat subcutaneous tissue / 대한치주과학회지

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.

The histometric analysis of osseointegration in hydroxyapatite surface dental implants by ion beam-assisted deposition / 대한치주과학회지

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.

The effects of Hydroxyapatite nano-coating implants on healing of surgically created circumferential gap in dogs / 대한치주과학회지

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.

The Effect of Recombinant Human Bone Morphogenetic Protein-2/Macroporous Biphasic Calcium Phosphate Block system on Bone Formation in Rat Calvarial Defects / 대한치주과학회지

No abstract available.

Influence of the Sonic Power Toothbrush on Reduction of Gingival inflammation and on the Amount of Interleukin-6, Prevotella intermedia and Actinobacillus actinomycetemcomitans in Periodontal Pocket / 대한치주과학회지

No abstract available.

Periodontal Repair on Intrabony Defects treated with Anorganic Bovine-derived Xeonograft / 대한치주과학회지

The ultimate goal of periodontal treatment is to regenerate the lost periodontal apparatus. Many studies were performed in developing an ideal bone substitute. Anorganic bovine-derived xenograft is one of the bone substitues, which were studied and have been shown successful for decades. The aim of this study is to evaluate the effect anorganic bovine-derived xenograft. Total of 20 patients, with 10 patients receiving only modified widman flap, and the other 10 receiving anorganic bovine-derived xenograft and flap surgery, were included in the study. Clinical parameters were recorded before surgery and after 6 months. The results are as follows: 1. The test group treated with anorganic bovine-derived xenograft showed reduction in periodontal pocket depth and clinical attachment level with statistically significance(p<0.001) after 6 months. The control group treated with only modified Widman flap showed reduction only in periodontal pocket depth with statistically significance(p<0.001) after 6 months. 2. Although periodontal probing depth change during 6 months did not show any significant differences between the test group and the control group, clinical attachment level gain and recession change showed significant differences between the two groups(p<0.05). On the basis of these results, anorganic bovine-derived xenograft improves probing depth and clinical attachment level in periodontal intrabony defects. Anorganic bovine-derived xenograft could be a predictable bone substitute in clinical use.

A Retrospective study of the type of patients, the distribution of implant and the survival rate of Xive(R) implant / 대한치주과학회지

This study is an analysis of types of patients and distribution of implant site and survival rate of Xive(R) implant. The following results on patient type, implant distribution and survival rate were compiled from 324 implant cases of 140 patients treated at the periodontal dept. of Yonsei University Hospital and G dental clinic between February 2003 and April 2006. 1. There are no dissimilarities between men and women, with patients in their 30, 40, 50s accounting for 80% of patients and accounted for 82% of implant treatments; the largest share of patients and implant treatments. 2. Mn. posterior area accounted for 57% of implant treatments followed by Mx. posterior area(29%), Mx. anterior area(8%) and Mn. anterior area(6%). 3. Partial edentulous patients treated by single crown and bridge-type prosthesis accounted for 96% and fully edentulous patient accounted for the remaining 4%. 4. The major cause of tooth loss is periodontal disease, followed by dental caries, trauma and congenital missing. 5. The distribution of bone quality for maxillae was 54.2% for typeIII, followed by 30.8% for type II, 15% for typeIV and 0% for typeI. As for mandible, the distribution was 63% for typeII, followed by 34% for typeIII, 2.5% for typeI and 0.5% for typeIV. 6. The distribution of bone quantity for maxillae was 55% for type C, followed by 35% for type B, 8% for type D and 2% for type A. As for mandible, the distribution was 60% for type B, followed by 32% for type C, 7% for type A and 0% for type D. 7. The majority of implants were those of 9.5-13 mm in length(95%) and regular diameter in width(82%). 8. The total survival rate was 98%. The survival rate was 97% in the maxillae region and 99% in the mandible region. 9. The survival rate in typeI was 83%, in typeII was 99%, in typeIII was 97% and in typeIV was 100%. As for the bone quantity, the survival rate in type A and D(100%) was most, followed by type B(99%) and type C(96%). The results showed that Xive(R) implant could be used satisfactorily compare for the other implant system. But we most to approach carefully in certain extreme condition especially with poor bone quality and quantity.

Measurement of soft tissue thickness on posterior palatal area by using computerized tomography in Korean population / 대한치주과학회지

The purpose of this study was to measure the thickness of masticatory mucosa in the hard palate as a donor site for mucogingival surgery by using computerized tomography(CT). Thickness measurements were performed in 84 adult patients who took CT on maxilla for implant surgery and 24 standard measurement points were defined in the hard palate according to the gingival margin and mid palatal suture. Radiographic measurements were utilized after calibration for standardization. Data were analyzed to determine the differences in mucosal thickness by gender, age, tooth positions and depth of palatal vault. The results of this study were as follows: 1. Mean thickness of palatal masticatory mucosa was 3.93+/-0.6mm and females had significantly thinner mean masticatory mucosa(3.76+/-0.56mm) than males(4.04+/-0.6mm)(p0.05). The results suggest that canine and premolar area appears to be the most appropriate donor site for soft tissue grafting procedure. The measurement of the thickness of palatal masticatory mucosa by using computerized tomography can offer useful information clinically but further studies in assessing the validity and reliability of the method using computerized tomography is needed.

Histologic evaluation of macroporous biphasic calcium phosphate(MBCP(R)) and flouorohydrxyapatite(Algipore(R)) in surgically created 1-wall periodontal intrabony defects of minipigs / 대한치주과학회지

Periodontal regenerative therapy and tissue engineering on defects destructed by severe periodontitis need maintaining of space, which provides the environment for cell migration, proliferation and differentiation. Application of bone grafts may offer this environment in periodontal defects. This study evaluated bone graft materials, MBCP(R) and Algipore(R), in surgically created 1-wall periodontal intrabony defects of minipigs by histological analysis. Critical sized(4mmX4mm), one wall periodontal intrabony defects were surgically produced at the proximal aspect of mandibular premolars in either right and left jaw quadrants in four minipigs. The control group was treated with debridement alone, and experimental group was treated with debridement and MBCP(R) and Algipore(R) application. The healing processes were histologically observed after 8 weeks and the results were as follows. 1. In the control group, limited new bone formation was observed. 2. In MBCP group, more new bone formation was observed compared to other groups. 3. Histologically, dispersed mixture of new bone, biomaterial particles and connective tissue were shown and osteoblasts, osteoclasts and new vessels were present in this area. 4. Defects with Algipore showed limited new bone formation and biomaterial particles capsulated by connective tissue. 5. Histologically, lots of osteoclasts were observed around the biomaterial but relatively small numbers of osteblasts were shown. Within the limitation to this study protocol, MBCP(R) application in 1-wall intrabony defect enhanced new bone formation rather than Algipore(R) application.

Effects of various membranes on periodontal tissue regeneration: a meta-analysis of the histomorphometry / 대한치주과학회지

Various periodontal barrier membranes used in many clinical and experimental fields, and many recent studies of membranes have reported good results. To improve clinical results, selection of barrier membranes is an important factor. So, we need not only to evaluate various barrier membranes, but also to understand the property of barrier membranes appropriate to defect characteristics. For this purpose, this study reviewed available literature, evaluated comparable experimental models, and compared various barrier membranes. From above mentioned methods, the following conclusions are deduced. 1. In 1-wall periodontal defect models, new bone formation showed a consistent result, almost 30% of the defect size. New cementum formations measured mostly 40% of the defect size, but showed more variations than new bone formations. This seems to be resulted form difference in experimental methods, so standardization in experimental methods is needed for future studies. 2. Application PLGA barrier membrane to periodontal defect demonstrated improved healing in new bone and new cementum. 3. There was a minimal periodontal regeneration with calcium sulfate barrier membrane only. But, there was better healing pattern in combination of calcium sulfate membrane with bone graft material, such as DFDBA. 4. There was no significant difference between the experimental group that used chitosan membrane only and the control group. But, in combination with bone graft material for space maintanence, periodontal regeneration was improved. Overall, Space maintenance is a critical factor for Guided tissue regeneration using barrier membranes. Also, a barrier membrane itself that has difficulty in maintaining space, achieved better result when used with graft material.

Long-term evaluation of implant placed in sites grafed by lateral window approach on maxillary sinus; a 10-year retrospective study / 대한치주과학회지

Between 1997 May and 2007 May, One hundred and seventeen patients were treated. There were 129 cases of sinus elevation using a lateral window opening procedure and 258 implants placed simultaneously or delayed. The cumulative survival rate of the implants calculated. The implants were evaluated according to surgical site, quality and quantity of bone, graft material, membrane used, the length and diameter of the implant and complications. 1. The 10-year cumulative survival rate of the implants by sinus augmentation using lateral window approach was 96.90%. 2. There was no difference in the survival rate between the implant placed simultaneously with sinus elevation (one stage) and the procedure performed in the delayed procedure (two stage). 3. There was no difference in the survival rate according to the type and amount of graft materials. 4. There was no difference in the survival rate according to the implant site, bone quality and quantity. 5. There was no difference in the survival rate when the CollaTape(R) or Gore-Tex was placed in the window of the lateral wall. 6. There was no difference in the survival rate of the implant length and diameter. 7. The survival rate was as low as 75.00% when there were more than two complications. Implant placement with sinus augmentation using the lateral window approach is a predictable treatment method. Although the vertical height of residual ridge is insufficient and the quality of bone is poor, the normal survival rate of the implants would be expected if an appropriate graft material and membrane is used with greater effort to prevent complications.

A Retrospective study on Branemark TiUnite(R) implant for mandibular posterior single tooth replacement / 대한치주과학회지

The purpose of this study was to evaluate 6 years cumulative survival rate (CSR, %) of mandibular posterior single tooth implants replaced with Branemark TiUnite(R) implant system. The findings from this study were as followed ; 1. The 112 (111 persons) single implants that were placed in the mandibular posterior region were successful except 4 cases and showed 96.42% CSR. 2. The 55 (55 persons) single implants that were placed in the mandibular first molar region were successful except 2 cases and showed 96.36% survival rate. And, among the 57 (56 persons) single implants replacing the mandibular second molar, 2 failed showing 96.49% survival rate. There was no significant statistical difference. 3. Among the total 112 implants, 5.0mm wide diameter implants were placed in 96 cases(85.7%) showing 96.9% survival rate. 4.0mm standard diameter implants were placed in 16 cases showing 93.8% survival rate. There was no significant statistical difference. 4. Long implants above 10.0mm length were placed 103 cases(91.0%) and showed 96.1% survival rate. Short implants within 8.5mm length were placed 9 cases and showed 100% survival rate. There was no significant statistical difference. 5. 37 implants placed in typeI,II bone quality were showed higher survival rate(100%) than that of 52 implants placed in typeIII, IV bone quality(92.3%). But, there was no significant statistical difference. In conclusion, Branemark TiUnite(R) implant showed successful results when replacing manbibular single molar.

A study of the clinical effects of various bone graft materials / 대한치주과학회지

PURPOSE: Various bone graft materials are being used for periodontal tissue regeneration.Th materials are being developed continuously for ideal clinical effects. Therefore, it is necessary to identify the clinical characteristics of each bone graft material through comparing the various bone graft materials statistically and in doing so, proposing a more efficient bone graft material. In this study, the following results were attained through comparing the clinical effects among the bone graft materials, using the statistical method based on the clinical studies published at the department of periodontology of Yonsei hospital. MATERIALS AND METHOD: 6 selected studies of department of Periodontology at Yonsei University Hospital were based on clinical study of bone grafting in intrabony defects. It was compared the clinical parameters among the 6 clinical studies, using the statistical META analysis. RESULT: When comparing the probing depth reduction, there was a relatively great amount of decrease when using the xenograft, Anorganic Bovine Derived Hydroxapatite Bone Matrix/Cell Binding Peptide(ABM/P-15: PepGen P-15(R)) and the autogenous bone and absorbable membrane, d,l-alctide/glycolide copolymer(GC: Biomesh(R)). The allogfrafts showed a relatively low decrease in the probing depth and clinical attachment change. It also showed a slight decrease in the bone probing depth. The allografts showed various results according to different bone graft materials. When comparing the ABM/P-15 and bovine bone powder(BBP(R)), ABM/P-15 showed a relatively high clinical attachment level and the bovine bone powder showed a relatively high clinical attachment level. The probing depth change and gingival recession change showed a lower value than the mean value between the two bone graft materials. The synthetic bone showed a relatively high decrease in clinical attachment level and periodontal probing depth change. There was a relatively larger amount of gingival recession when using Bioactive Glass(BG) but a relatively low bone regeneration effect was seen. CONCLUSION: Good restorative results of the periodontal tissue can be attained by applying the various bone graft materials being used today after identifying the accurate clinical effects.

The Analysis of Bone regenerative effect with carriers of bone morphogenetic protein in rat calvarial defects / 대한치주과학회지

Bone morphogenetic proteins have been shown to possess significant osteoinSductive potential, but in order to take advantage of this effect for tissue engineering, carrier systems are essential. Successful carrier systems must enable vascular and cellular invasion, allowing BMP to act as a differentiation factor. The carrier should be reproducible, non-immunogenic, moldable, and space-providing, to define the contours of the resulting bone. The purpose of this study was to review available literature, in comparing various carriers of BMP on rat calvarial defect model. The following conclusions were deduced. 1. Bone regeneration of ACS/BMP, beta-TCP/BMP, FFSS/BMP, FFSS/beta-TCP/BMP, MBCP/BMP group were significantly greater than the control groups. 2. Bone density in the ACS/BMP group was greater than that in beta-TCP, FFSS, FFSS/beta-TCP carrier group. 3. Bone regeneration in FFSS/BMP group was less than in ACS/BMP, beta-TCP/BMP, MBCP/BMP group. However, New bone area of FFSS/beta-TCP/BMP carrier group were more greater than that of FFSS/BMP group. ACS, beta-TCP, FFSS, FFSS/beta-TCP, MBCP were used for carrier of BMP. However, an ideal carrier which was reproducible, non-immunogenic, moldable, and space-providing did not exist. Therefore, further investigation are required in developing a new carrier system.

Retrospective studies of dental implant placement at each intraoral site and situation / 대한치주과학회지

PURPOSE: Developments in micro/macrostructures of implants and surgical techniques brought out stable outcomes of implant dentistry. The aim of this study was to evaluate the distributions of implant patients, the types of implanted sites, and the success or survival rates of various implant systems and to analyze the implant placement done at each specificintraoral site and situation. MATERIALS AND METHODS: The data of dental implantations collected between 1992 and 2006 at the Department of Periodontology in 00000 University Hospital were analyzed. RESULTS: 1. Largest part of the patients were at the age of 40s and 50s in bothgender who lost their teeth mostly by periodontaldiseases and caries at the posterior intraoral sites as major ones. Bone densities of type II(mandible) and III(maxilla) were likely to be seen with quantity of type B. Lengths of the implants between 10 and 15 mm and wide platform took the largest part. 2. Survival rates of Implantium(R)(98.8%), Xive(R)(100%) and ITI TE(R)(100%) were high when Frialit-2(R) showed 82%(poor bone density area) or 87.2%(combined with additional therapy). IMZ(R) had lowest cumulative survival(67.5%) and success rate(49.4%) amongst all. 3. Replacement with 2 wide or 3 regular platforms showed no significant differences in survival rate and marginal bone loss atmandibular posterior area. In single restoration of mandibular second molar, 5-year success rate of machined surface Branemark(R)(70.37%) was lower than that of rough surface ITI(R) SLA(100%). 4. Replacement of single tooth in anterior area showed high survival rate of 94.5%. 5. The success rates of Branemark Ti-Unite and ITI SLA at posterior maxilla with poor bone density both showed stable outcomes. 6. 10-year cumulative survival rate of implants with maxillary sinus augmentation by lateral window approach appeared to be 96.60%. Low survival rate(75%) was shown when there were more than two complications combined. Height of grafted bone remained stable above the implant apex. CONCLUSIONS : Rough surfaced implants showed stable outcomes in most of the situation including poor bone density and additional therapy combined.

Initial tissue response of biodegradable membrane in rat subcutaneous model / 대한치주과학회지

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.