Retrospective study on the survival rate of IBS implant Date : 30. 05. 2013 Written by : Dr. Je Won Wang, Director of research Approved by : Prof. Min Seung Ki
- Contents - 1. Purpose Of Study 2. Materials and Methods 3. Study Results 4. Discussion and Conclusion 5. Reference 6. Clinical Cases
1. Purpose Of Study The aim of this study was to do research retrospectively on the degree of stabilization, loss of marginal bone, and survival rate of IBS Anker Implants (submerged type, RBM surface) that had been placed on patients missing tooth sites and make evaluation of their stability in comparison with the results of previously conducted researches. 2. Materials and methods 2.1 Research materials The materials targeted in this study are Anker Implants (Innobiosurg. Co., LTD, Korea) whose surfaces are RBM-treated and that have an internal connection between abutment and fixture. The fixtures used in this study features macro threads on their tapered bottom sides and micro threads on their straight top sides. The fixtures are 3.8~6.3mm in diameter and 7~13mm in length, which are described in detail in Figures 1 and 2. Fig.1 Fig.1 Anker Anker regular Regular implant Implant used on on clinical clinical evaluation evaluation research. research. Fig.2 Anker Wide Wide Implant implant used used on on clinical clinical evaluation evaluation research. research.
2.2 Methods 2.2.1 Target patients This study targeted ** dental implants that had been placed in ** patients under the IBS Implant System, who received their surgery at one of the 5 dental clinics including ** Dental Clinic and *** Dental Clinic between MM, YY and MM, YY. This study included all the target implants that met certain conditions, but actual examination and analysis were conducted on the patients who continued to visit the clinics for one year before and after the placement of implants and for 6 months after the completion of prostheses. All other patients that did not meet the criteria were excluded. Medical charts were used to do research on such information as patient s age and sex, their health conditions, implant locations and distribution, implants specifications, bone quality on surgical sites, and implant surgery outcomes. All the target patients, except for those who tested positive for the contraindications that were specified by the manufacturer, underwent oral examinations and radiographic tests. 2.2.2 Methods Surgical treatments for dental implants and prostheses were performed under the one-stage procedure or the two-stage procedure while patients were put under generally known local anesthesia, where placement time was defined as when a fixture was placed in bone and final prosthesis completion time was determined as when a crown was fixed with permanent adhesive. Target patients information and surgery information were investigated; the research items were listed in the attached file entitled Clinical Evaluation Report ; and the radiographs taken at each stage were collected. The intraoral radiographs taken before surgery, after surgery, and after prosthesis-mounting were measured by the unit of 0.1mm from respective reference points, which were set in reference to the uppermost part of an implant. (Fig. 3) Reference point Fig.3 Illustration of the reference point
A failure in implant surgery was determined in accordance with the conditions presented by Albreksson et al [1] and Zarb and Albreksson [2] and with the clinical failure conditions of the implant s qualitative evaluation criteria which were classified by Misch into 5 groups. - Criteria - When thermal damage was suspected in the course of placement procedures due to radioactive penetration into the areas surrounding the implant after the placement or during treatment. - When it was judged that a fixture allowed movement during the secondary surgery or a fixture was rotated together when it was tightened to its abutment, leading to failure in the osseointegration. - When a patient complained of pain when they used the prosthesis after its final completion or when the tooth was percussed (tapped). When a fixture had been fractured. For calculation of the survival rate of implants and categorization of failure types, analyses were performed on the patients who continued to see their doctors at the 5 dental clinics under study for more than one year. 2.2.3 Information on target dental clinics and patients Name of Surgeon Name of Clinic Academic background Career of Implant Surgery Use career of IBS products Number of annual implant surgery Wang Je Won Hyewon Dental Clinic Wonkwang Univ. Department of dentistry 18 5 About 800 Cha So Angel Smile Dental Clinic Lycum North Western Univ. Department of dentistry 7 2 About 350 Kim Soon Geom Kim Soon Geom Dental Clinic Chosun Univ. Department of dentistry 11 4 About 500 Lee Young Ik Lee s beauty Dental Clinic Wonkwang Univ. Department of dentistry 10 3 About 250 Kang Boo Hwan Geumcheon Yonsei Dental Clinic Yonsei Univ. Department of dentistry 10 4 About 300
3. Study results 3.1 Analysis of target patients Analysis was conducted on patients who had lost their natural teeth with a view to making followup investigation after the completion of placement of IBS implants and verifying their stability. (1) Target patients: were selected from those who met all of the following conditions: 1) Adult patients who were 18 years or older and had fully grown jaw bones 2) Patients who had firm motivation to receive implant surgery 3) Those who agreed on participation in clinical tests and signed their research consent forms 4) Patients who had not developed any temporomandibular disorders or occlusal problems (2) Exceptions: the patients who met any of the following conditions were excluded from the study: 1) Who were pregnant 2) Who had recently suffered an attack of myocardial infarction 3) Who had uncontrollable internal disorder 4) Who had developed hemorrhagic disorder or had diseases that required anticoagulants 5) Who had had mental disorder or suspected of having developing mental disorder 6) Who were allergic to the materials of dental implants 7) Who had been found to be ethically or morally improper or inappropriate to the participation of the clinical tests as it might cause influences on the result of such tests. 8) Who had lost maxillary molar areas sitting opposite to mandibular molar areas where implants were planned to be placed (except for who had those area restored with, or planned to restore, those areas with prostheses) 9) Who had less than 8mm in height of the alveolar bones where implants were to be placed 10) Who had suffered from systematic disorder so serious as not to proceed with extraction surgery 11) Who had other problems with the placement of implants (e.g., a person changes teeth, or a person has no space for a prosthesis to be placed, etc.)
1) Distribution of the patients age and sex The total number of the target patients was 82 persons and the number of the target implants totaled 151 pieces. 71 implants were placed in 43 male patients (52.3%) and 80 implants were planted in 39 female patients (47.6%). One patient had an average of 1.8 implants placed (Table 1). Table I. The patient characteristics according to Sex SEX No. of Patients (%) No. of Implant placed (%) Male 43 (52.4%) 71 (47 %) Female 39 (47.6%) 80 (53%) Total 82 (100%) 151 (100%) The number of implants placed in and the number of patients who were either 20 years or younger or 70 years or older were both relatively few. The number of the patients in their 50s and 60s took the majority and the number of implants was the largest in the patients in their 50s (Table II). Table II. The patient characteristics according to Age Age No. of Patients (%) No. of Implant placed (%) < 20 5 (6.1%) 5 (3.3%) 20~29 12 (9.8%) 8 (5.3%) 30~39 14 (8.5%) 9 (6.0%) 40~49 15 (18.3%) 16 (10.6%) 50~59 21 (25.6%) 43 (28.5%) 60~69 21 (25.6%) 48 (31.8%) > 70 5 (6.1%) 22 (14.6%) Total 82 (100%) 151 (100%) 2) Patients overall health conditions 15 out of 82 patients were smokers; however, the medical examination revealed that the patients overall physical conditions were good, free of systematic disorder, and that hypertension was the most frequent disorder with 12 patients among those who were found to have such disease (Table III).
Table III. The distribution of patients with general health disorders Table III. The distribution of patients with general health disorders No. of Patients Hypertension 12 Osteoporosis 6 Cerebral infarction 6 Diabetes 2 Hepatitis B 1 Hypothyroidism 2 Asthma 1 Valvular heart disease 2 Myocardial infarction 1 Smoking 15 3) Location and distribution of implants Out of a total of 151 implants, 93 (61.6%) were placed on the maxilla while 58 (38.4%) on the mandible; and 89 (58.9%) implants placed on molar areas were more than those placed on anterior areas with 62 (41.1%),. The maxillary molar areas had the highest distribution with 55 implants. (Table IV & Fig 4) Table IV. The distribution of Implants Table IV. The distribution of Implants Anterior (%) Posterior(%) Total (%) Maxillary 38 (25.2%) 55 (36.4%) 93 (61.6%) Mandibular 24 (15.9%) 34 (22.5%) 58 (38.4%) Total 62 (41.1%) 89 (58.9%) 151 12 Location of Implants by Max. tooth position 10 8 6 4 2 0 #17 #16 #15 #14 #13 #12 #11 #21 #22 #23 #24 #25 #26 #27
9 8 7 6 5 4 3 2 1 0 #37 #36 #35 #34 #33 #32 #31 #41 #42 #43 #44 #45 #46 #47 4) Specifications of implants IBS implants placed were 7, 9, 11, and 13mm in length and had diameters of 3.8, 4.3, 4.8, 5.3, 5.8, and 6.3mm, which comprised a full range available at IBS. 7mm implants were mostly placed on molar areas, while 13mm ones were mainly placed on anterior areas. Implants with small diameters of 3.8 and 4.3mm were mostly placed on anterior areas, while those with larger diameters than 4.8mm were mainly placed on molar areas (Table V). Table V. Implant distribution of Length and Diameter Table V. Implant distribution of Length and Diameter Maxillary Mandibular Anterior Posterior Anterior Posterior 7mm 0 11 0 5 9mm 6 31 7 16 Length 11mm 25 8 15 13 13mm 7 5 2 0 Total 38 55 24 34 Φ3.8 7 3 12 3 Φ4.3 26 16 3 9 Φ4.8 5 25 0 15 Diameter Φ5.3 0 4 0 8 Φ5.8 0 3 0 5 Φ6.3 0 4 0 2 Total 38 55 24 34
5) Bone condition analysis on surgical areas The bone shapes of the surgical areas were evaluated and recorded during surgery according to the classification by Lekholm and Zarb [1]. The records showed that the large portion of the bones where implants were places was classified into either D2 or D3; on the other hand, D1 bone was mostly found on mandibular anterior areas, whereas D4 was largely discovered on maxillary molar areas (Table Vi). Table VI. Implant distribution Table according VI. Implant to distribution bone quality according by Letholm to bone and quality Zarb by classification Letholm and Zarb classi Quality D1 13 D2 57 D3 67 D4 14 Total 151 6) Implant surgery IBS implants were applicable in either the 1-stage or 2-stage system, depending on individual circumstances. 47 implants were placed right after extraction and 43 implants within 2 months after extraction, mostly on mandibular and maxillary anterior areas. Most of the delayed placements were performed on maxillary molar areas, especially around maxillary sinus areas. In terms of the surgical method, the 1-stage system was largely used, especially on both mandibular and maxillary anterior areas, while the 2-stage system was performed on maxillary molar areas together with bone augmentation procedures (Table VII). Table VII. Number of implants in relation to treatment type Table VII. Number of implants in relation to treatment type No. of Implants Immediate placement 27 Early placement 53 Placement type Delayed 71 Total 151 1 Stage 97 Surgical treatment 2 Stage 54 type Total 151 7) The shapes of prostheses The types of the prosthesis mounted include single tooth restoration, multiple teeth restoration, and denture in the order of frequency. They were mostly cement retained types (Table VIII).
Table VIII. Characteristics of prothesis Table VIII. Characteristics of prothesis Type of prothesis Retained type No. of Implant Single 76 Bridge 63 Denture 12 Total 151 Cement 139 Screw 0 O-ring 12 Total 151 8) Follow-up period until now and analysis of failures As of April 30, 2013, a minimum of 2 months up to a maximum of 2 years and 4 months had passed since their placement, which could also translate into an average of 18.5 months after the placement and an average of 21.7 month after the completion of prosthesis. One failure had been reported till then (Table IX). The failure developed after 4 months of the placement, in which case the bone of the patient s maxillary sinus was found to belong to D4, where 3 implants were placed under the 2-stage system. The patient did not have any systematic disorder but he had the habits of smoking and drinking. He was meticulously informed of the precautions following the surgery but it was found that he had not observed such instructions. It was presumed that was the reason why his implants failed to achieve osseointegration. Table IX. Follow up period after implants prosthesis F/ up period after prosthesis ~2M ~6M ~12M 12M ~ total ea 3 18 72 58 151 % 2.0 11.9 47.7 38.4 100 9) Results of radiological measurement Radiological analysis showed that, during re-visit periods, the resorption amount of marginal bone was measured to be an average of 0.43mm with a standard deviation of 0.753, where the bone resorption occurred greatly on the medial side than on the distal side. Bones were resorbed more greatly around the implants placed together with bone augmentation procedures than around marginal bones without bone lifting procedures. However, the t-test of the 2 samples did not show any significant statistical difference between two groups (ρ=0.34).
Table X. Marginal Bone Loss Total (n=151) Non Augmentation group Augmentation group (n=104) (n=47) mean mesial distal mean mesial distal mean mesial distal Mean 0.430 0.526 0.334 0.354 0.374 0.334 0.506 0.608 0.403 SD 0.572 0.637 0.484 0.472 0.541 0.451 0.584 0.612 0.536 10) Analysis of survival rates and comparison with previous studies The survival table summarized the analysis of the total 151 implants in the total 82 patients. 148 implants in the total of 81 patients had survived during the research period (January, 2011 through April, 2013), calculated to be a survival rate of 98%. The failure involved 3 implants in 1 patient; however, no failure in implant surgery resulted after the mounting of prostheses. In comparison with the survival rate and the bone resorption amount measured of the products of similar properties that were investigated by previous studies in terms of implant surface, connection type, and application method, our survival rate turned out to be the highest with 98% and the bone resorption amount proved to be similar (Table XI). Table XI. Comparison of various or Marginal bone loss Authors (Ref. No.) Type of implant Surface Type Company Follow-up Period Survival rate Marginal Bone loss This study RBM Internal submerged IBS 12~30M 98.00 0.43 Kim et al [4] RBM Internal submerged Osstem 15M 97.63 0.28 Yang et al [5] RBM Internal nonsubmerged Renova 12M 96.88 0.88 Shin et al [6] SLA Internal submerged Implantium 12M 1.32 Nam et al [7] RBM Internal submerged Osstem 12~36M 95.6 0.31
4. Discussion and conclusion This study focused on the calculation of survival rates from the implants that had been placed in missing tooth sites in accordance with patients age, bone density on placement sites, fixtures diameter and length, the locations of placement site, and surgical methods. A successful implant surgery might be influenced by such elements as clinicians experience, patients oral habits, oral hygiene, biocompatibility of implant materials; so, previous studies attempted to focus on surgical procedures performed by skillful and experienced dentists with a view to reducing the effects of such influential factors. However, this study tried to increase reliability through the collection of data from 5 dental clinics selected at random from a population that had used IBS s implants and the analysis of the survival rates of implants. The study by Kim, Soo-yeon and Kim, Young-gyun [4] showed a survival rate of 97.63% and a bone resorption amount of 0.28±0.57mm, and the study by Yang, Jinhyeok et al [5] came up with a survival rate of 96.88% and a bone resorption amount of 0.88mm. In comparison with products with same shapes, same surface treatment, and same surgical procedures, IBS implants exhibited a survival rate of 98.00%, which was higher than its counterparts, while it displayed an average bone resorption amount of 0.43mm, which produced a similar result as in other studies yet showed a considerably good result when compared with the level of bone resorption of less than 1~1.5mm within a year as suggested by Albrektsson et al [1] as a successful implant surgery. A patient had a problem with two implants; when he made masticatory movements, he suffered severe pain, which was found through a periodontal probe to originate from inflammation. He was in his 60s and did not follow his doctor s postoperative precautions and continued to smoke and drink excessively, which presumably caused such failure. In summary, the study found that IBS implants had a high survival rate of 98.00%, where survival rate is an index to indicate implant stability, and a bone resorption amount of 0.43mm, which showed results similar to or better than other implants currently available on the market, and concluded with such results that IBS implants were safe.
5. References [1] Albrektsson T, Zarb GA, Worthington P, Ericsson AR. The long-term efficacy of currently used dental implants: A review and proposed criteria of success. Int J Oral Maxillofac Implants 1986;1:11-25. [2] Zarb GA, Albrektsson T. Consensus report: towards optimized treatment outcomes for dental implants. J Prosthet Dent 1998;80: 641-648. [3] Misch CE. Contemporary Implant Dentistry. 2nd ed. Mosby, 1999:21-32. [5] Lekholm U, Zarb GA. Patient selection and preparation. In:Brånemark P-I, Zarb G.A., Albrektsson T.(eds). Tissue-integrated prostheses:osseointegration in clinical dentistry.chicago:. Quintensence 1985:199-209. [6] Kim SY, Kim YK Short-term retrospective clinical study of Resorable blasting media surface tapered implants. J Korean Oral Maxillofac Implants, 33;2:149-153. [7] Yang JH, Kim ST, Jung EW, Nam W, Jung YS, Sim JS, Moon HS, Lww KW, Cho KS, Choi SH multilateral analysis of Renova implant placement and its survival rate. J Korean Acad Periodontol 2008:38:413-428 [8] Shin YK, Han CH, Heo SJ, et al. Radiographic evaluation of marginal bone level around implants with different neck designs after 1 year. Int J Oral Maxillofac Implants 2006;21:789-794. [9] Nam Gy, Chang BS, Uhm HS. Retrspective analysis of several implants success rate. J Korean Acad Periodontol 2003;33:37-47.
6. Clinical cases 1) CASE #1 Information Name : Lee Soon *** Gender : Female Age : 35 Date of installation : 03.01.2011 / 20.01.2011 / 06.05.2012 Location of installation : #13, 14, 15, 16, 21, 23, 24, 25, 26, 35, 36 46,47 Bone quality : D3 (soft) Fixture size : IBS4811 Prosthetics date / method : 07.04.2011 / 05.09.2012 / close Quantity Consumed : 13 unit Operation Method (1-1 or 2-2) : 2-2 Sinus : GBR : Narrow Ridge : Immediate Loading : X Clinic Name : Hyewon Dental Clinic Surgeon Name : Wang Je Won
6. Clinical cases 2) CASE #2 Information Name : Oh Jeong *** Gender : Female Age : 66 Date of installation : 20.02.2012 Location of installation : #34 Fixture size : IBS3811 Bone quality : D3 (soft) Prosthetics date / method : 07.02.2013 / close Quantity Consumed: 3 unit Operation Method (1-1 or 2-2) : 2-2 Sinus : X Narrow Ridge : GBR : Immediate Loading : X Clinic Name : Angel Smile Dental Clinic Surgeon Name : Cha So
6. Clinical cases 3) CASE #3 Information Name : Song Seong *** Gender : Male Age : 53 Date of installation : 27.03.2012 Location of installation : #45, #47 Fixture size : IBS4313, IBS4811 Bone quality : D2 (hard) Prosthetics date / method : 25.05.2012 / close Quantity Consumed: 2 unit Operation Method (1-1 or 2-2) : 2-2 Sinus : X Narrow Ridge : X GBR : X Immediate Loading : X Clinic Name : Kim Soon Geom Dental Clinic Surgeon Name : Kim Soon Geom
6. Clinical cases 4) CASE #4 Information Name : Kim Hyeon *** Gender : Female Age : 26 Date of installation : 23.03.2012 Location of installation : #24 Fixture size : IBS4811 Bone quality : D3 (soft) Prosthetics date / method : 14.12.2012 / close Quantity Consumed: 1 unit Operation Method (1-1 or 2-2) : 2-2 Sinus : socket Narrow Ridge : X GBR : Immediate Loading : X Clinic Name : Lee s beauty Dental Clinic Surgeon Name : Lee Young Ik
6. Clinical cases 5) CASE #5 Information Name : Park Jin *** Gender : Female Age : 60 Date of installation : 16.04.2012 Location of installation : #44 Fixture size : IBS4313 Bone quality : D2 (hard) Prosthetics date / method : 12.11.2012 / close Quantity Consumed: 1 unit Operation Method (1-1 or 2-2) : 2-2 Sinus : X Narrow Ridge : X GBR : Immediate Loading : Clinic Name : Geumcheon Yonsei Dental Clinic Surgeon Name : : Kang Boo Hwan