임플란트 직경이 골유착에 미치는 영향에 관한 연구

이준호,신상완,권상호,Lee Jun-Ho,Shin Sang-Wan,Kwon Sang-Ho 대한치과보철학회 2003 대한치과보철학회지 Vol.41 No.2

Statement of problem : The survival rate of wide diameter implants was lower than of 3.75-mm implants in some clinical researches. Purpose : The purpose of this study was to investigate the influence of implant diameter on the osseointegration of implants in the rabbit femoral condyle and tibial metaphyses by means of removal torque measurements and histomorphometric analysis. Material and Method : Ten adult New Zealand White rabbits were used in this study Two 3.75-mm diameter implants were inserted through one cortical layer in the tibial metaphyses and one 3.75-mm diameter implant was inserted in the femoral condyle. 5.0-mm diameter implants were inserted in the other leg in the same manner. A total of 60 implants (3.75-mm diameter implants:30 : 5.0-mm diameter implants:30) were installed. After a healing time of 4 and 12 weeks, the peak removal torque values required to shear off the implants were recorded. From the removal torque values (Ncm) obtained, the mean shear stress ($N/mm^2$) was calculated. And the percentage of direct bone-to-implant contact and the percentage of bone area inside the thread were measured by Kappa Image Base-metreo. The Student's t-test was undertaken for statistical analysis (p<0.05). Results : The removal torque value of 5.0-mm diameter implants was higher than of 3.75-mm diameter implants (p<0.05). The difference of shear stress value between 3.75-mm and 5.0-mm diameter implants was not statistically significant (p>0.05). The percentage direct bone-to-implant contact had no statistical difference between two groups (p>0.05). The percentage of bone area inside the thread had no statistical difference between two groups (p>0.05). Conclusion It is concluded that the quality f osseointegration is not influenced by increasing implant diameter.

Implant and root supported overdentures - a literature review and some data on bone loss in edentulous jaws

Gunnar E Carlsson 대한치과보철학회 2014 The Journal of Advanced Prosthodontics Vol.6 No.4

PURPOSE To present a literature review on implant overdentures after a brief survey of bone loss after extraction of all teeth. MATERIALS AND METHODS Papers on alveolar bone loss and implant overdentures have been studied for a narrative review. RESULTS Bone loss of the alveolar process after tooth extraction occurs with great individual variation, impossible to predict at the time of extraction. The simplest way to prevent bone loss is to avoid extraction of all teeth. To keep a few teeth and use them or their roots for a tooth or root-supported overdenture substantially reduces bone loss. Jaws with implant-supported prostheses show less bone loss than jaws with conventional dentures. Mandibular 2-implant overdentures provide patients with better outcomes than do conventional dentures, regarding satisfaction, chewing ability and oral-health-related quality of life. There is no strong evidence for the superiority of one overdenture retention-system over the others regarding patient satisfaction, survival, peri-implant bone loss and relevant clinical factors. Mandibular single midline implant overdentures have shown promising results but long-term results are not yet available. For a maxillary overdenture 4 to 6 implants splinted with a bar provide high survival both for implants and overdenture. CONCLUSION In edentulous mandibles, 2-implant overdentures provide excellent long-term success and survival, including patient satisfaction and improved oral functions. To further reduce the costs a single midline implant overdenture can be a promising option. In the maxilla, overdentures supported on 4 to 6 implants splinted with a bar have demonstrated good functional results.

치과용매식체의 생체반응에 대한 실험적 연구

조재오,임호남 대한구강악안면병리학회 2006 대한구강악안면병리학회지 Vol.30 No.6

The purpose of this study was to observe the histopathologic tissue reaction in vital bone in applying the various treated implants. For this purpose, twelve New Zealand Albino rats, weighing 3.3 to 4 kg were used as experimental animals. All the experimental groups divided into four groups; Machined surface as control, RBM(resorbable blast media), Hydroxyapatite-sand and Porous coating groups. All the experimental implants were examined under the scannning electron microscope. All the experimental rabbits were implanted in the tibial metaphyses of rabbits under the general anesthesia with Ketamine HCl(2.5ML /kg.body wt.) injections. For prevention of infection after implant, prophylactic erythromycine injections, 250mg/body wt.(Aldrich Co. USA) were performed on each. On the sixth week after implant, all the experimental rabbits were sacrificed with over dose of Sedaject(Samwoo Pharm .Co. Korea). All the tissues containing each experimental materials were fixed in ethyle alcohol, and embedded in spurr resin(Polytechnic Co. USA) as usual manner. sectioned in 12 um thickness, grinded , stained with the Vulenueva's osteochrome stain methed and examined histopatholgically. For measuring the distances between the implant and bone without any connective tissue interface, all the distances were calculated the length of the implant direct contact to bones. using the view analyzer program( Korea Optical Co.) and the statistical analysis were performed using the one-way ANOVA test. The statistical differences were considered significant below 5% level. Following results were obtained. On the scanning electron microscopic examination, dull cracked continuous linear indentations were revealed on the machined surface implant, irregular sharp indentation on the resorbabale blast, irregular thin exophytic or indentated leaflets on the hydroxyapatite-sand implant, and long ovoid globular particles were revealed on the porous coating implant surface respectively. On the histopathologic examination, complete osseointegation was noted between the implant and cortex bone on the collar and the apex lesion and in parts, small newley formed bone spicules attached to the screws in marrow tissues with compatibility in all experimental groups, but on the aspect of the tissue compatibility to the various implant materials, the superiority of the materials could not identified. The ratio of drect contact between the bone and implant, the HA sand gorup was the most superior among the gorups and followed by the machine surface, but on RBM and porous coating groups were inferior compared to that on the experimental groups. With these results, the superiority of tissue compatibility among the experimental implant group could not be identified

Survival and Success Rate of Implants in Overdentures: Analyzing Patient and Implant Factors

김효식,이상민,안강민 대한구강악안면임플란트학회 2023 대한구강악안면임프란트학회지 Vol.27 No.1

Purpose: Edentulism can be treated using removable prostheses, fixed prostheses, and implant overdentures. Implant overdentures are more cost-effective than fixed prostheses and offer advantages of retention, support, stability, masticatory power, psychological stability, maintenance of alveolar bone, and improvement of proprioception compared to removable dentures. This study aimed to investigate the survival and success rate of implants in overdentures according to patient and implant factors. Materials and Methods: This study investigated patients who underwent implant surgery for overdenture treatment by a single surgeon at the Oral and Maxillofacial Surgery Department at Seoul Asan Medical Center between 2005 and 2020. A total of 46 patients with 146 implants were included, and the survival and success rates of the implants were analyzed statistically. Additionally, the correlation between these rates and age, sex, implant placement location, and the number of implants was investigated. Results: A total of 146 implants were placed in 46 patients for implant overdentures. The average follow-up period for this study was 5.03 ± 3.89 years. The mean age of the patients was 68.5 ± 9.9 years, and there were 19 men and 27 women. The most commonly placed implants were in the mandibular anterior region, and the majority of dentures had two implants. The overall survival and success rates of implants in overdentures were 98.6% and 95.9%, respectively. Age, sex, implant placement location, and the number of implants showed no significant correlation with implant survival and success rates. Conclusion: The survival and success rates of implants for overdentures are extremely high, with no significant difference from those for fixed prosthetics.

Effectiveness of ultra-wide implants in the mandibular and maxillary posterior areas: a 5-year retrospective clinical study

So-Yeon Kim(So-Yeon Kim),Hyeong-Gi Kim(Hyeong-Gi Kim),Pil-Young Yun(Pil-Young Yun),Young-Kyun Kim(Young-Kyun Kim) 대한구강악안면외과학회 2023 대한구강악안면외과학회지 Vol.49 No.1

Objectives: Ultra-wide implants may be used as a replacement if existing implants fail. This study was conducted to evaluate the factors influencing the prognosis and failure of ultra-wide implants. Patients and Methods: This study evaluated whether sex, age, site, diameter, length, additional surgery, implant stability (primary and secondary), and reason for ultra-wide implant placement affect the 5-year survival and success rates and marginal bone loss (MBL) of ultra-wide implants. Seventy- eight ultra-wide implants that were placed in 71 patients (39 males and 32 females) from 2008 to 2010 were studied. One-way ANOVA analysis was conducted to evaluate the statistical significance of MBL according to the patient’s sex, implant site, and diameter. Independent sample t -tests were used to determine the statistical significance of MBL analysis which was used to determine the significance of the 5-year success and survival rates related to the variables. One-way ANOVA was conducted to evaluate the statistical significance of sex, implantation site, diameter, and MBL. Independent sample t -tests were used to evaluate the correlation between implantability and MBL for implantation reasons, while additional surgery, length, and Kaplan-Meier analysis were used to evaluate 5-year survival and success rates. Results: The mean age of patients was 54.2 years with a survival rate of 92.3% and a success rate of 83.3% over a mean 97.8-month period of observation. MBL averaged 0.2 mm after one year of prosthetic function loading and 0.54 mm at the time of final observation. Success rates correlated with primary stability (P=0.045), survival rates correlated with secondary stability (P=0.036), and MBL did not correlate with any variables. Conclusion: Ultra-wide implants can be used to achieve secure initial fixation in the maxillary and mandibular molar regions with poor bone quality or for alternative purposes in cases of previous implant failure.

Implant survival and risk factor analysis in regenerated bone: results from a 5-year retrospective study

Hong, Ji-Youn,Shin, Eun-Young,Herr, Yeek,Chung, Jong-Hyuk,Lim, Hyun-Chang,Shin, Seung-Il Korean Academy of Periodontology 2020 Journal of Periodontal & Implant Science Vol.50 No.6

Purpose: The aims of this study were to evaluate the 5-year cumulative survival rate (CSR) of implants placed with guided bone regeneration (GBR) compared to implants placed in native bone, and to identify factors contributing to implant failure in regenerated bone. Methods: This retrospective cohort study included 240 patients who had implant placement either with a GBR procedure (regenerated bone group) or with pristine bone (native bone group). Data on demographic features (age, sex, smoking, and medical history), location of the implant, implant-specific features, and grafting procedures and materials were collected. The 5-year CSRs in both groups were estimated using Kaplan-Meier analysis. Risk factors for implant failure were analyzed with a Cox proportional hazards model. Results: In total, 264 implants in the native bone group and 133 implants in the regenerated bone group were analyzed. The 5-year CSRs were 96.4% in the regenerated bone group and 97.5% in the native bone group, which was not a significant difference. The multivariable analysis confirmed that bone status was not an independent risk factor for implant failure. However, smoking significantly increased the failure rate (hazard ratio, 10.7; P=0.002). Conclusions: The 5-year CSR of implants placed in regenerated bone using GBR was comparable to that of implants placed in native bone. Smoking significantly increased the risk of implant failure in both groups.

인접치아가 임플란트 치은연하 세균총의 분포에 미치는 영향

이동영,이만섭,권영혁,박준봉,허익,정종혁,Lee, Dong-Young,Lee, Man-Sub,Kwon, Young-Hyuk,Park, Joon-Bong,Herr, Yeek,Chung, Jong-Hyuk 대한치주과학회 2005 Journal of Periodontal & Implant Science Vol.35 No.3

The aim of present study is to evaluate the influence of adjacent tooth to the microbiology of clinically healthy implant. Control group included patients who had clinically healthy implant and tooth with healthy $periodontium(PD{\leq}3mm)$, test group was composed of patients who had clinically healthy implant and tooth with periodontal pocket(PD>3mm). The criteria of clinically health implant are no pain or discomfort, the restorative suprastructure provide satisfactory fit and function, and the tissue around the fixtures were firm and probing with standard periodontal probe with a rounded tip 0.5mm in diameter resulted in penetration of no more than 5mm when using a force of 0.5N at any location. 38 patients, partially edentulous subjects with endosseous root-form implants were selected. All subjects were medically healthy and had not taken systemic antibiotics and professional plaque control 3 months before sampling. Number of control group is 25(mean age $52{\pm}13$, 26 teeth, 34 implants) and test group is 13(mean age $60{\pm}13$, 13 teeth, 17 implants). All teeth and implants of each patient were examined probing depth(PD), bleeding on probing(BOP), and plaque index(PI), and samples of subgingival plaque were obtained at each site with sterile curet or fine paper points, then the plaque transferred to PBS. Obtained samples were examined for the presence of P. gingivalis, T. forsythensis, and T. denticola by the polymerase chain reaction(PCR). The relationship among clinical parameters and the colonizations by the 3 bacterial species from natural teeth and implants region were analyzed by student t-test. The results of this study were as follows: 1. PD was different in teeth between 2 groups(p<0.05), but the other parameters were not. 2. Statistically significant difference was not found in clinical parameters of implants between 2 groups. 3. All bacterial prevalences of teeth were higher in test group than in control group, and prevalence of T. forsythensis had statistically significant difference between 2 groups(p<0.05). 4. Prevalences of P. gingivalis and T. forsythensis are higher in test group than control group, and that of T. denticola is higher in control group than in test group. But there were no statistically significant differences between 2 groups. In conclusion, there is no statistically significant difference in prevalence of implant microbiology between 2 groups. But if the number of samples increased, it will be possible to find out statistical significance in prevalence of P. gingivalis. It seems that pocket of adjacent tooth influences prevalence of P. gingivalis. These results mean that improvement of the periodontal condition before implantation is very important.

Single and two implant-supported overdentures: A comparison of objective prognostic parameters and QOL

Niharika Yadav(Niharika Yadav ),Deeksha Arya(Deeksha Arya ),Saumyendra Vikram Singh(Saumyendra Vikram Singh ),Kamleshwar Singh(Kamleshwar Singh ),Mayank Singh(Mayank Singh ),Divya Mehrotra(Divya Mehro 대한치과이식임플란트학회 2022 The Korean Academy of Implant Dentistry Vol.41 No.3

Purpose: This study compared a) crestal bone loss, b) implant stability quotient (ISQ), c) probing depth, d) denture fracture incidence, and e) posterior residual ridge resorption (RRR) of two implant and single implant-supported overdentures and assessed the quality of life (QOL) was evaluated before and after giving the prosthesis. Materials and Methods: The study was a randomized longitudinal cohort study. Eighty subjects were selected for the study and divided randomly into two groups (n=40): Group 2IOD— two implant-supported overdentures; Group 1IOD— Single implant-supported overdentures. Except for the number of implants, the common surgical, implant, and the prosthetic protocol was followed for the two groups. An oral health impact profile EDENT questionnaire was completed by the patients before giving the implant-supported overdenture and after one year of prosthesis delivery to evaluate the effects of oral health on the quality of life. Probing pocket depth (mm), ISQ (resonance frequency analysis), denture fracture incidence, posterior RRR (mm), and crestal bone loss (mm) were assessed and compared at the baseline and one year after implant placement (early loading protocol) for the two groups. Standard statistical tests, including an unpaired t-test with SPSS software, were used for the analysis. Results: The average crestal bone loss in group 2IOD was insignificantly lower than group 1IOD. The ISQ values were higher for group 2IOD than group 1IOD at one year. The ISQ values for both groups at 12 months were similar (P>0.05). The probing depth at both time intervals yielded insignificant intergroup differences. No denture fracture was reported in either group. At 12 months, posterior ridge resorption in group 2IOD was 0.33±0.08, which was significantly lower than in group 1IOD. Conclusions: A one implant-supported overdenture is a comparable treatment option with two implant-supported overdentures for edentulous patients, having the advantages of lower cost and less surgical trauma. However, there may be more posterior RRR with this treatment modality.

Implant Stability Change Measurement of Flaplessly Placed Immediate Implant on Mandibular First Molar

태양열,정찬호,박관수 대한구강악안면임플란트학회 2020 대한구강악안면임프란트학회지 Vol.24 No.3

Purpose: This study aims to evaluate the stability change of implants placed immediately after extraction of the mandibular first molar with Resonance Frequency Analysis (RFA). Materials and Methods: For 24 patients, 25 implants with sandblasted, large grit, and acid-etched (SLA) surface were placed with flapless surgery. Implant stability at implant placement and impression taking procedure were measured with Osstell ISQ. The average interval between implant placement and impression taking was 1.82 months, and implants' success rate was 100%. The average follow-up period was 23.8 months. Results: The average RFA value of implants measured in all directions increased by 6.4, and the average RFA value measured in the buccolingual direction increased by 5.9. Moreover, the average RFA value measured in the mesiodistal direction increased by 6.9. There was a statistically significant difference between the buccolingual side's RFA value and the RFA value in the mesiodistal side at implant placement. There was not a completely linear relationship between the RFA value at implant placement and insertion torque. Conclusion: The change of RFA value can be a useful evaluation method for implant stability of the immediately placed implant after tooth extraction. It may help evaluate the healing of immediately placed implant and determine the appropriate loading time.

임플랜트의 지대주 연결방식, 임플랜트의 직경 및 지대주 연결부위의 직경 차이에 따른 응력분포에 관한 삼차원 유한요소분석

오세웅,양재호,이선형,한중석,Oh Se-Woong,Yang Jae-Ho,Lee Sun-Hyung,Han Jung-Suk 대한치과보철학회 2003 대한치과보철학회지 Vol.41 No.4

Statement of problem. Higher incidence of prosthetic complications such as screw loosening, screw fracture has been reported for posterior single tooth implant. So, there is ongoing research regarding stability of implant-abutment interface. One of those research is increasing the implant diameter and prosthetic table width to improve joint stability. In another part of this research, internal conical type implant-abutment interface was developed and reported joint strength is higher than traditional external hex interface. Purpose. The purpose of this study is to compare stress distribution in single molar implant between external hex butt joint implant and internal conical joint implant when increasing the implant diameter and prosthetic table width : 4mm diameter, 5mm diameter, 5mm diameter/6mm prosthetic table width. Material and method. Non-linear finite element models were created and the 3-dimensional finite element analysis was performed to see the distribution of stress when 300N static loading was applied to model at $0^{\circ},\;15^{\circ},\;30^{\circ}$ off-axis angle. Results. The following results were obtained : 1. Internal conical joint showed lower tensile stress value than that of external hex butt joint. 2. When off-axis loading was applied, internal conical joint showed more effective stress distribution than external hex butt joint. 3. External hex butt joint showed lower tensile stress value when the implant diameter was increased. 4. Internal conical joint showed lower tensile stress value than external hex butt joint when the implant diameter was increased. 5. Both of these joint mechanism showed lower tensile stress value when the prosthetic table width was increased. Conclusion. Internal conical joint showed more effective stress distribution than external hex joint. Increasing implant diameter showed more effective stress distribution than increasing prosthetic table width.