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.
Bone Density ; Dental Implants* ; Dentistry ; Humans ; Maxilla ; Maxillary Sinus ; Molar ; Retrospective Studies* ; Survival Rate ; Tooth ; Transplants

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

BACKGROUND/AIMS: It is still unclear whether Super Paramagnetic Iron Oxide-Magnetic Resonance Imaging (SPIO-MRI) is a clinically useful imaging modality for patients with hepatocellular carcinoma (HCC). This study searched for the clinical usefulness and limitations of SPIO-MRI with respect to tumor detection capacity, false positive and negative rate, and early recurrence rate. METHODS: From December 1999 to February 2001, 218 patients who were surgical candidates by 3-phase dynamic helical CT (3dHCT) were enrolled. We reviewed the medical records and radiologic findings, retrospectively, and postulated the post-operative pathologic findings and the early recurrences within 3 months as the standards for the true positive lesion. RESULTS: The mean number of nodules detected by SPIO-MRI was significantly more numerous than that of 3dHCT (p<0.01). Modifications of treatment strategy due to the discordant findings between SPIO-MRI and 3dHCT for tumor resectability were observed in 22 (10.1%) out of 218 patients. Early recurrences were observed in 10 patients (7.8%). The false positive and negative rates of SPIO-MRI were 6.3% and 13.3%, respectively. CONCLUSIONS: We demonstrated that the tumor detection rate of SPIO-MRI was better than that of 3dHCT. Given the relatively acceptable false positive and negative rates, SPIO-MRI could be an appropriate preoperative imaging modality for patients with HCCs.
Adult ; Aged ; Carcinoma, Hepatocellular/*diagnosis ; *Contrast Media ; False Negative Reactions ; False Positive Reactions ; Female ; Ferrosoferric Oxide ; Humans ; Iron/*diagnostic use ; Liver Neoplasms/*diagnosis ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Oxides/*diagnostic use ; Tomography, Spiral Computed

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

This study is an analysis of distribution of patients who installed Implantium(R) implant in Yonsei University Dental Hospital and types of implant site for about 1 years recall check and success rate. 164 implants were installed to 52 patients in this study. It shows the conclusion below. 1. Patients at the age of 40s and 50s were 65% of all implant cases and average number of implant was 4 (man), and 2.7 (woman). 75 implants were operated on maxilla and 89 were mandible. 19 implants on anterior region and 145 implants on posterior region. 2. Most distribution of bone qaulity for implant site was type III(37.2%) and bone quantity was type C(61.7%) 3. The majority of implants were those of 10, 12mm in length (85%) and regular diameter in width (48.8%). 4. 30 implants were installed with the advanced technique-GBR, window opening, osteotome technique. 5. Two implants were removed before prosthodontic treatment due to the osseointegraton failure. The success rate was 98.8% in 15.2 months follow up period and the marginal bone loss was 0.28mm. The results provided us with basic data on patient type, implant distribution, bone condition, and survival rate. Within the limit of present study, It was concluded that Implantium(R) implant could be used satisfactorily in various clinical situations.
Follow-Up Studies ; Humans ; Mandible ; Maxilla ; Prosthodontics ; Survival Rate

Recent study shows that implant design has a great impact on initial stability in bone. The ITI TE(R) implant, designed originally for immediate placement has a tapered/ cylindrical form which fits the anatomical shape of the natural alvelous or tooth root. The increased diameter at the collar region coupled with more threads lead to more bone contact and enhanced stability. The aim of this retrospective study is to evaluate the clinical use and the efficacy of recently introduced ITI TE(R) implant with a new macro-design. The following results are compiled from 139 patients who received ITI TE(R) implant surgery at the periodontal department. of Yonsei University Hospital between July 2002 and September 2005. 1. 139 patients received 173 ITI TE(R) implants in their maxilla and mandible (Mx 82, Mn 91). Posterior area accounted for 84% of the whole implant surgery. 2. In the distribution of bone quality, type III(41.0%) was the most, followed by type IV(41.0%) and type II (27.7%). As for the bone quantity, type B(43.9%) was the most, followed by type C(42.2%), type D(12.2%) and type A(1.7%). 3. 125 implants(83.9%) were treated by single crown, which accounted for the majority. 4. The total implant survival rate was 100% after a mean follow-up period of 21.2 months. This preliminary data with ITI TE(R) implant showed excellent survival rate although the majority of implants evaluated in this study were placed in the posterior region of the jaw and compromised sites.
Ants* ; Crowns ; Follow-Up Studies ; Humans ; Jaw ; Mandible ; Maxilla ; Retrospective Studies* ; Survival Rate* ; Tooth Root

The purpose of this study was to evaluate cumulative survival rate (CSR, %) of mandibular posterior single tooth implants replaced with ITI SLA (sand-blasted, large-grit, acid-etched) implant system and compare the CSR between first and second molar. The findings from the results were as follows; 1. Total of 158 implants were inserted into 147 patients. 68 patients were males, 79 patients were females and their mean age was 47.8 years. 98 implants were placed in first molar area and 60 implants were placed in second molar area. In terms of diameter, implants with wide diameter over 4.8mm dominated (91.1%). Implants with length over 10mm were used (96.2%). 2. In the two cases, there was a slight transient numbness which recovered within 1-2 months. Nine SynOcta screw type abutments demonstrated screw loosening. There were ten cases of crown fallen-out from decementation. 3. Only one failed out of 158 implants. The CSR was 99.4%. The CSRs for first molar and second molar were 99% and 100%, respectively. From the results, it was concluded that single tooth replacement implant in the mandibular posterior area, might be considered as the effective treatment modality comparable to the conventional crown and bridge.
Crowns ; Dental Implants, Single-Tooth ; Female ; Humans ; Hypesthesia ; Male ; Molar ; Retrospective Studies* ; Survival Rate ; Tooth*