1 0483 ISO 9001:2000, ISO 13485:2003 FDA Clear for marketing MIS Corporation. All rights Reserved. MCSS002 Rev.1 MIS Implants Technologies Ltd. Shlomi Industrial zone P.O.Box 110 Shlomi 22832, ISRAEL Tel: +972 (0) Fax: +972 (0)
2 2Volume 2. Scientific studies Make it Simple
3 MIS Corporation. All rights Reserved. Published by MIS, which reserves the right to ameliorate the products described in this manual as well as to revise this publication at any time and without informing any person of such revision or change. All rights reserved. No part of this publication may be reproduced, transcribed, stored in an electronic retrieval system translated to any language or computer language, or be transmitted in any form whatsoever without a written consent of the publisher.
4 Index. P. 5 Different survival rates in full maxillary vs. mandibular immediate restoration. P. 9 The incidence of marginal bone loss and failure rate of MIS internal hex. implants bearing different types of prosthesis. P. 13 Radiographic changes of immediately restored implants in periodontally susceptible patients. P. 17 Immediate implantation and immediate loading on lower incisors with MIS Dental Implant System TM. P. 21 MIS technical surface review. P. 2 9 Enhancement of bone formation by bone morphogenetic protein2 during alveolar distraction: an experimental study in sheep.
6 1 Different survival rates in full maxillary vs. mandibular immediate restoration. One year results *A poster presented in the AAP congress, Denver
7 6 Different survival rates in full maxillary vs. mandibular immediate restoration. One year results Jacob Horwitz *, Otman Zuabi *, Eli E. Machtei **, Micha Peled ** Aim of study Purpose: Immediate restoration of dental implants in patients with periodontal disease was examined. We evaluated the influence of insertion torque (IT) and Implant Stability Quotient (ISQ) on the survival and success of dental implants and compared those parameters in mandibular vs. maxillary and extraction vs. non extraction site implants. Materials and Methods: Patients received periodontal treatment after which treatment of the implant region was performed as "all in one": hopeless teeth were extracted, periodontal surgery around remaining adjacent teeth was performed, implants were inserted, and a fixed screwed provisional restoration was delivered. IT and ISQ levels were recorded at baseline, 6 and 12 month post surgery. Results: Nineteen patients were treated, receiving 74 implants. Twelve implants in 4 patients failed, ten of which were maxillary. Survival rates were 93% in mandibular full arches, 52% in maxillary full arches, and 100% in partial arch restorations. Implants exhibited a decrease in ISQ at 6 months followed by an increase at 12 months. There was no statistically significant difference between failed and successful implants in IT and ISQ. Non extraction and extraction sites demonstrated no significant differences in IT, and ISQ. Mandibular implants demonstrated a higher IT and ISQ at baseline, 6 and 12 months. Conclusions: Immediate loading of dental implants in periodontally susceptible patients has a high survival rate in the mandible and in restoring partial edentulism. This procedure proved unpredictable in the restoration of a fully edentulous maxilla. Introduction The successful use of dental implants for over three decades has been extensively documented. Implant therapy has been used for full arch and partial arch as well as single tooth restorations. Implant therapy also serves as an acceptable treatment for the replacement of periodontally hopeless teeth. In a recent review of the literature (van der Weijden et al. 2005), implant patients that were previously treated for periodontitis were shown to run a greater risk for developing complications, evidenced by loss of supporting bone and implant loss, as compared to individuals without such a history. The general aim of our study was to examine immediate restoration of dental implants in periodontally susceptible patients. Specific aims were: 1) to evaluate the influence of primary stability, as measured by insertion torque (IT) and resonance frequency analysis (ISQ) 1 on the survival and success of dental implants and 2) to compare those parameters in immediately restored vs. non restored implants, in immediate vs. delayed implants and in maxillary vs. mandibular implants. Materials and Methods Patients attending the Unit of Periodontology at the Rambam Medical Center were offered to participate in the study if they met the following criteria: Aged 1875, Diagnosed as having chronic periodontitis and in need of fixed implant restorations of the entire maxilla or mandible or a fixed partial implant restoration in the esthetic zone or a single tooth implant restoration in the esthetic zone. Had no complicating systemic conditions which were contraindications for surgical periodontal treatment and implant treatment (i.e. pregnancy or uncontrolled diabetes). Patients received periodontal treatment, including oral hygiene instructions, scaling and root planning, and periodontal surgery as necessary, after which final eligibility was ascertained. The study was carried out in accordance with the Helsinky Declaration guidelines. All patients signed a consent form. Study models, periapical, panoramic and CT radiographs were used for evaluation * Rambam Health Care Campus, Haifa, Israel. ** Faculty of Medicine, Technion, Haifa, Israel. Table 1 Implant distribution between jaws. Table 2 Survival rates Table 3 Extraction vs. Non Extraction, comparison between groups (mean±s.e.) Maxillary implants. (patients) Mandibular implants. (patients) Total implants. (patients) Variable Total N 74 Failed 12 Survival Rate 84% Variable Insertion Torque Non Extraction 38.7±1.6 Extraction 38.3±1.2 P Single Tooth 4 (4) 1 (1) 5 (5) Maxilla full arch % Insertion ISQ 63.8± ± Partial Arch 21 (7) 13 (5) 34 (10) Mandible full arch % ISQ 6m 59.7±2 60.3± Full Arch 21 (3) 14 (2) 35 (5) Partial arch % ISQ 12m 66.1± ± Total 46 (14) 28 (8) 74 (19) Single tooth % ISQ 60m 4.72± ± Anterior % ISQ 126m 6.45± ± Posterior % ISQ 120m 1.68± ± Table 4 Maxillary vs. Mandibular implants, comparison between groups (mean±s.e.) Table 5 Survival rates according to loading categories. Variable Maxilla Mandible P Variable No. Total No. Failed Survival Rate Ins. Torque 36.44± ± R non extraction % Insertion ISQ 60.64± ± R extraction % ISQ 6m 57.97± ± S non extraction % ISQ 12m 64.06± ± S extraction % ISQ 60m 3.79± ± NSNR non extraction % ISQ 126m 6.09± ± NSNR extraction % ISQ 120m 2.38± ± RRestored implants SSubmerged implants NSNRNon Submerged Non Restored implants
8 7 and treatment planning. A surgical stent and a provisional fixed restoration were fabricated prior to commencement of the combined implantprosthetic treatment. All provisional restorations were screw retained. For the region where implants were planned in conjunction with tooth extraction, this was performed as "all in one" in which hopeless teeth were extracted, periodontal surgery around remaining adjacent teeth was performed where necessary and implants 2 were inserted, guided by the surgical stent. In partial cases 24 implants were selected and in full arch cases 34 implants were selected as abutments for a provisional restoration. The restoration was prefabricated in the laboratory and adapted to those implants. Briefly, conical abutments were screwed in with a 20Ncm torque. Gold cylinders were screwed to the conical abutments, the restoration was connected to the gold cylinders with acrylic resin and screwed out to be adapted and finished extraorally. Finally, the restoration was delivered to the patient, occlusally adjusted and screwed into the conical abutments with a 20 Ncm torque. Single implants were similarly restored with a screwed in crown restoration fabricated from acrylic. The following guidelines were used: 1. a passive fit to the implants, 2. no contact of the restoration with adjacent teeth, 3. single and partial arch restorations were delivered with no occlusal contact of the restoration with the opposing arch in IC and no contact in lateral and protrusive movements, 4. full arch restorations had a balanced occlusion. The rest of the implants either received a healing abutment and left to heal as non submerged one stage implants or received a cover screw and were submerged for a period of 6 months. Patients were prescribed a postoperative CHX 0.2% mouthwash, amoxicillin 500mg TID for seven days and analgesic therapy as necessary. Patients were examined 710 days after surgery for suture removal and then after two, 4 and 8 weeks and 3 months. At 6 months the restoration was removed, interim implant success was evaluated, second stage surgery was performed for the submerged implants, ISQ was recorded, periapical radiographs taken and patients were referred for final prosthetic restorations. Failed implants were removed and additional implant surgery was provided as necessary to enable successful prosthetic restorations. ISQ measurements and periapical radiographs were again taken 12 months post surgery. Results Results are presented in the following tables. Briefly, nineteen patients were treated, receiving 74 implants. Twelve implants in 4 patients failed, ten of which were maxillary. Survival rates were 93% in mandibular full arches, 52% in maxillary full arches, and 100% in partial arch restorations. Implants exhibited a decrease in ISQ at 6 months followed by an increase at 12 months. There was no statistically significant difference between failed and successful implants in IT and ISQ. Non extraction and extraction sites demonstrated no significant differences in IT, and ISQ. Mandibular implants demonstrated a higher IT than maxillary implants at baseline and a higher ISQ at 12 months. ISQ at baseline and 6 months was also higher though not statistically different. Discussion Overall survival rate in the literature ranges between 80% 3 and 100% 4 Survival rates were 93% (13/14 implants) in full arch mandibular cases, while it was 52% (11/21 implants) in full arch maxillary cases, and 100% (34/34 implants) in partial cases Several factors may contribute to this phenomenon. First, it might possibly be related to the lower mechanical stress that the maxilla can withstand because of its lower density and thinner cortical plates 5. We would speculate that a micromotion exceeding the critical threshold of 150µm can partly explain failures in the present study. Second, the patient group of our study was periodontally susceptible. It has been shown that periodontally susceptible patients exhibit greater failure rates. Hardt 6 described 8.0% failures for perio patients vs. 3.3% for nonperio patients and Evian 7 described 21% vs. 8% failure rates for perio vs. non perio cases, respectively. Conclusions Immediate loading of dental implants in periodontally susceptible patients has a high survival rate in the mandible and in restoring partial edentulism. This procedure proved unpredictable in the restoration of a fully edentulous maxilla. Acknowledgement This study was supported by a scientific grant from MIS ltd. ISRAEL. References 1 Osstell TM Integration Diagnostics AB, Gamlestadsvägen 3B, SE Göteborg, Sweden. 2 MIS Implants Technologies Ltd. P.O.B. 110, Shlomi 22832, Israel. 3 Balshi TJ, Wolfinger GJ. Immediate loading of Brånemark implants in edentulous mandibles: a preliminary report. Implant Dent 1997;6: Misch, C.E. & Degidi, M. (2003) Fiveyear prospective study of immediate/early loading of fixed prostheses in completely edentulous jaws with a bone qualitybased implant system. Clinical Implant Dentistry and Related Research 5: Kourtis SG, Sotiriadou S, Voliotis S, Challas A. Private practice results of dental implants. Part I: survival and evaluation of risk factorspart II: surgical and prosthetic complications. Implant Dent. 2004;13: Hardt, C.R., Grondahl, K., Lekholm, U. & Wennstrom, J.L. Outcome of implant therapy in relation to experienced loss of periodontal bone support: a retrospective 5 year study. Clinical Oral Implants Research 2002;13, Evian CI, Emling R, Rosenberg ES, Waasdorp JA, Halpern W, Shah S, Garcia M. Retrospective analysis of implant survival and the influence of periodontal disease and immediate placement on longterm results. Int J Oral Maxillofac Implants. Case 1 Case 2 Cantilever bridge on hopeless tooth #12 Flap elevation and tooth extraction, showing residual osseous defect Three implants in positions #12, 13, 14. conical abutments connected to implants # 12, 13. Four hopeless mandibular incisors Residual ridge after flap elevation and extractions Surgical guide used for implant positioning Fig 1 Fig 2 Fig 3 Fig 9 Fig 10 Fig 11 Provisional restoration adapted and screwed to implants. Note absence of contact with tooth # 11. Baseline radiographic view Occlusal view 6 months post surgery ISQ measurement with Osstell transducer Resorbable membrane adaptation Grafting with DFDB Fig 12 Fig 13 Fig 14 Fig 4 Radiographic view 6 months post surgery, after 2nd stage surgery and abutment connection to implant # 14. Fig 5 Clinical view with provisional restoration on all three implants. Fig 6 Flap closure and insertion of provisional restoration ISQ ISQ measurement history Fig Fig 7 Fig Data of measurement LL LR
10 2 The incidence of marginal bone loss and failure rate of MIS internal hex. implants bearing different types of prosthesis. A Longterm retrospective analysis. *A poster presented in the EAO meeting, Munich
11 10 The incidence of marginal bone loss and failure rate of MIS internal hex. implants bearing different types of prosthesis. A Longterm retrospective analysis. Moshe Tandlich 1, Pini Reizman 2, Lior Shapira 1 Aim of study The aim of this study was to retrospectively evaluate the success rate of internal hex oral implants (MIS implants), installed in a private clinic milieu, after longterm function, and to construct a multivariate correlation model between crestal bone loss and formerly documented proposed predictors (i.e. time, smoking habits, type of abutments, type of prosthesis etc). Materials and methods Patients treated in a private clinic (PR) with oral implants were recalled for a routine dental exam. The exam included a full record of their health condition, habits, state of the prosthetic appliance and their treatment timeline. Only patients who had concluded more than 30 months of followup time were included in this study. Collected data included records of the patients smoking habits, their type of prosthesis (RPD or FPD), the prosthesis span and configuration (e.g. cantilevered pontics, implant to tooth splinting, etc.), type of abutments 1 Dept. of Periodontology, Hadassah Medical Centers, Jerusalem, Israel. 2 Private Practice, Hurdegaryp, The Netherlands. Fig. 1 Calculation of The actual bone loss Actual bone loss = Radiographic bone loss x Known implant length Radiographic implant length Graph 1 10 Patient average bone loss by time of function 5 Patient average bone loss by type of abutment Correlation between patient mean bone loss and some of the suspected variables. The patient mean bone loss serves as the unit of analysis. Crestal bone loss is found to be significantly correlated only with smoking habits. No statistically significant correlation is found between crestal bone loss and time of function. Bone loss (mm) r 2 = ; r = , p = Bone loss (mm) * p< Function time (months) Mean ± SE 0 Milled abutment Cast abutment Patients' average bone loss by type of prosthesis Patient average bone loss by smoking habits * Bone loss (mm) 3 2 Bone loss (mm) Mean ± SE 0 Removable Fixed Mean ± SE 0 Smoker Non Smoker
12 11 used (milled or cast abutments), time of implant installation (immediate, early or late), length of service etc. A panoramic radiogram was taken to evaluate the state of the prosthesis, and was used to measure the amount of crestal bone loss around each implant. The actual bone loss was calculated using the formula (see Fig. 1) Statistical analysis Descriptive statistics were used to report the success rates of the implants. Two different approaches were engaged to analyze the correlation between crestal bone loss and the suspected prognostic variables: In one, each patient s mean crestal bone loss was used as a unit of analysis, and in the other the single implant bone loss served for the statistics. Linear regression and ANOVA were used to describe correlation between suspected variables and crestal bone loss. Results One hundred and ninety implants installed in 46 patients were evaluated, having between thirty months and 9 years with an average of 5.3 years of followup time. Five (2.6%) implants failed and were removed prior to the prosthetic phase (early loss), and another 4 implants failed through time of service (2.1% of all evaluated implants), 3 of them in a patient suffering from osteoporosis. 181 implants were found to be present at the followup examination, however three of them were never rehabilitated, and thus were termed sleeping. The overall success rate was 95.3%. None of the suspected variables was found to be correlated with a failure event. The patients average calculated bone loss was 2.99 mm leaving an average of 0.83 threads exposed. Smoking was the only predictor that was correlated with higher bone loss when data was evaluated using the patient as the unit of analysis. Neither time, nor any of the other suspected variables were found to be correlated with higher bone loss. Removable prosthesis was marginally correlated with higher bone loss (p=0.053). By evaluating the data with the single implant serving as the unit of analysis, time of function (p=0.03), smoking and presence of removable prosthesis (p<0.05) were found to be correlated with higher bone loss. Although the correlation between bone loss and time was found to be statistically significant, its strength was low (r 2 =2.5%), presenting a mm calculated rate of monthly bone loss (i.e mm/year). Conclusions The results of the present study confirm that MIS internal hex implants exhibited an overall success rate of 95% after a longterm followup period. By evaluating the data with the patient serving as the unit of analysis only smoking habits were found to be correlated with higher crestal bone loss. None of the other suspected variables was found to be a statistically significant predictors of bone loss. Acknowledgement This study was supported by a scientific grant from MIS ltd. ISRAEL. Table 1 number of failed implants and their relative rates Early loss Late loss Number 5 4 Rate (%) % failure rate 'Sleeping' implants Functioning implants % success rate Total Sites' bone loss by time of function Site s bone loss by type of abutment Graph Correlation between each implant bone loss and some of the suspected variables. The single implant calculated bone loss serves as the unit of analysis. The implant bone loss is correlated with time of function, smoking habits and type of prosthesis. * p<0.05. Bone loss (mm) r 2 = ; r = , p = ; y= *x Bone loss (mm) Function time (months) Mean ± SE 0 Cast abutment Milled abutment Site s bone loss by type prosthesis Site s bone loss by smoking habits 5 4 * 5 4 * Bone loss (mm) 3 2 Bone loss (mm) Mean ± SE 0 Removable Fixed Mean ± SE 0 Non Smoker Smoker
14 3 Radiographic changes of immediately restored implants in periodontally susceptible patients. One year results. *A poster presented in the EAO meeting, Munich
15 14 Radiographic changes of immediately restored implants in periodontally susceptible patients. One year results. Zuabi O 1, Horwitz J 1, Peled M 2, Machtei EE 3 1 Unit of Periodontology, Department of Oral & Maxillofacial Surgery, Rambam Medical Center, Haifa, Israel. 2 Department of Oral & Maxillofacial Surgery, Rambam Medical Center. Faculty of Medicine, Technion, Haifa, Israel. 3 Unit of Periodontology, Department of Oral & Maxillofacial Surgery, Rambam Medical Center. Faculty of Medicine, Technion, Haifa, Israel. Abstract Objectives: 1. To evaluate the radiographic bone level changes ( CB) of immediately restored (R) vs. nonrestored (NR) dental implants. 2. To compare radiographic bone level changes between jaws and between healed and extraction sites in periodontally compromised patients. Materials & Methods: Chronic periodontitis patients with hopeless teeth received periodontal therapy after which implant surgery was performed and a provisional restoration immediately provided on part of the implants. Results are reported in mm as mean ±SE of bone level changes between insertion, 6 and 12 months. Results: 74 MIS implants were inserted in 19 patients, receiving 3 maxillary and 2 mandibular full arch cases, 7 maxillary and 5 mandibular partial arch cases and 5 single tooth cases, one of which was mandibular. 12 implants failed, resulting in an overall 84% survival rate, 78% in the maxilla and 94% in the mandible. R implants in extraction sites had a 65% survival rate vs. 94% in healed nonextraction sites. NR implants placed in extraction sites had a 86% survival rate vs. 100% in healed nonextraction sites. For R vs. NR groups CB0 6 months was 0.99±0.13 vs. 0.81±0.16 (p>0.05), CB612 months was 0.24±0.13 vs. 0.81±0.13(p<_0.05) and CB012 months was 1.27±0.18 vs. 1.67±0.17 (p>0.05). There were no differences in CB between any timepoint in extraction vs. nonextraction or in maxillary vs. mandibular implants. Conclusions: 1. First year bone level changes of immediately restored implants do not differ from those of nonrestored implants. 2. First year bone changes around immediately restored dental implants in periodontally susceptible patients were slightly higher than most reports in the literature. This indicates a potential influence of periodontal susceptibility and previous disease on the success rate of dental implants. Introduction Implant therapy serves as an acceptable treatment for the replacement of periodontally hopeless teeth. In a recent review of the literature (van der Weijden et al. 2005), implant patients that were previously treated for periodontitis were shown to run a greater risk for developing complications, evidenced by loss of supporting bone and implant loss, as compared to individuals without such a history. Likewise, Hardt (Hardt et al. 2002) also implicated a higher failure rate in patients who experienced loss of alveolarbone support. There are, however, other reports demonstrating survival rates in periodontally compromised patients that are not different from healthy patients (Baelum & Ellegaard 2004). Immediate restoration of dental implants has been gaining popularity in the last years (Jaffin et al. 2000, 2004; Gapski et al. 2003; Nikellis et al. 2004; Drago & Lazzara 2004, Tarnow et al. 1997). Survival and success rates in these publications seem to be similar to those of the traditional protocol of loading at 36 months after implant insertion. Obviously, patients with hopeless teeth due to periodontal disease would benefit from such a treatment modality, especially if those teeth could be extracted and immediately restored with implant supported crowns and/or bridges. Crestal bone loss is often used as a tool to evaluate implant status and, particularly, its success (Bragger 2000). Conventional radiography using the longcone paralleling technique, supported by positioning devices is generally used to evaluate marginal bone changes at interproximal sites of osseointegrated implants (Salvi & Lang 2004). More specifically, Crestal bone loss <_1.5mm in the first year is considered a criterion for implant success (Albrektsson et al. 1986). There is, as yet, little available information about radiographic bone changes in immediately restored implants in periodontally compromised patients, both short and long term. Aims 1. To evaluate the influence of immediate restoration on radiographic bone changes around dental Table 2 Restoration type, Analysis of Variance between groups (mean ± SE) variable R S NR P CBM Baseline 0.52± ± ± CBD Baseline 0.50± ± ± CB Baseline mean 0.52± ± ± Fig 1. CBM 06m 0.873± ± ± Table 1 General Data: Maxillary vs. mandibular implants CBD 06m CB mean 06m CBM 612m 1.09± ± ± ± ± ± ± ± ± Maxillary implants. (patients) Mandibular implants. (patients) Total (patients) CBD 612m 0.32± ± ± Single Tooth 4 (4) 1 (1) 5 (5) CB mean 612m 0.24± ± ± Partial Arch 21 (7) 13 (5) 34 (10) CBM 012m 1.19± ± ± Full Arch 21 (3) 14 (2) 35 (5) CBD 012m 1.33± ± ± Total 46 (14) 28 (8) 74 (19) CB mean 012m 1.27± ± ±
16 15 implants. 2. To compare radiographic bone changes between the maxilla and the mandible and between healed and extraction sites in periodontally compromised patients. Materials and Methods Inclusion criteria: 1. Healthy non pregnant patients with periodontitis aged Need a full or partial arch fixed implant restoration. 3. Had no contraindications for surgical periodontal treatment and implant treatment. Study models and CT radiographs were used for planning. A surgical stent and a screw retained metal reinforced acrylic provisional fixed restoration were prefabricated. Patients received periodontal treatment as needed. Screw type externalhex sandblasted acidetched implants were used 1. At least 3 implants were selected as abutments in full arch cases and 2 3 Implants were selected in partial arch cases. Implants were selected to serve as abutments according to location and stability, measured by Resonance Frequency Analysis (RFA) 2. We had three groups of implants: immediately restored (R), Submerged (S) and nonsubmerged nonrestored (NR). Periapical radiographs using a parallelism appliance 3 were taken at implant surgery, at 6 and 12 months post surgery. All radiographs were digitized and stored electronically using a scanner 4. Next, using a computersoftware for digital measurement 5, the distance between the alveolar crest and the implant shoulder was measured. Radiographic data is reported as the distance in mm between implant shoulder and alveolar bone crest (mean ± SE), both separately for the mesial (CBM) and distal (CBD) aspects of the implants and as a calculated mean of mesial and distal values (CB mean) (Figure 1). Data Management and Analysis Data analysis was performed in two ways using a statistical software program 6. Student ttest for paired observation was utilized to assess the changes from baseline to 6 ( CBM 06m and CBD 06m) and 12 months ( CBM 012m and CBD 012m) and from 6 to 12 months ( CBM 612m and CBD 612m) within the same treatment group. Student ttest for unpaired observations was used to compare those variables in the maxilla and mandible and in extraction and nonextraction sites. Analysis of variance (ANOVA) was used to compare data between the three loading groups, namely R, S and NR. A 95% significance level was used. Results 74 MIS implants were inserted in 19 patients, 17 females, receiving 3 maxillary and 2 mandibular full arch cases, 7 maxillary and 5 mandibular partial arch cases and 5 single tooth cases, one of which was mandibular (Tables 1). 12 implants failed, resulting in an overall 84% survival rate, 78% in the maxilla and 94% in the mandible. R implants in extraction sites had a 65% survival rate vs. 94% in healed nonextraction sites. NR implants placed in extraction sites had a 86% survival rate vs. 100% in healed nonextraction sites. Baseline bone levels were comparable in failed and surviving implants, mean bone levels ranging between 0.33±0.1mm and 0.52±0.24mm, (p>0.05). Mean baseline bone height was 0.52±0.14mm, 0.09±0.06 mm and 0.34±0.21 mm in the R, S and NR groups. There was a statistically significant difference in CBM 612m between R and S groups (0.27mm±0.17mm and 0.99mm±0.18mm respectively, p=0.0219) as well as a difference in CB mean 612m between those same groups (0.24±0.13 vs. 0.85±0.12, p=0.0096). Mean bone level changes ranged between 1.19±0.19 and 1.88±0.3mm in the various treatment groups with no difference between them (Table 2). Data from the S and NR groups was combined to form a Non Restored group, which was compared to the R group. There were statistically significant differences (p<0.05) between R and NR groups in baseline CBD and CB mean (0.50±0.13mm vs. 0.15±0.1mm and 0.52±0.11mm vs. 0.18±0.08mm) and in CBM 612m (0.27±0.17mm vs.0.91±0.16mm), CBD 612m (0.32±0.13mm vs. 0.77±0.15mm) and CB mean 612m (0.24±0.13mm vs. 0.81±0.13mm). No difference between groups was found for CB 012m (Table 3). Baseline bone level was higher in nonextraction vs. extraction sites (0.17±0.08mm vs. 0.57±0.15mm for CBM, 0.1±0.09mm vs. 0.56±0.13mm for CBD and 0.13±0.06mm vs. 0.58±0.12mm for CB mean, p<0.05). A significant difference in CBD 012m (1.81±0.16 vs. 1.25±0.21mm, p<0.05) was found (Table 4). Discussion In the present study mean baseline bone level was higher for submerged twostage implants (S group). Obviously, the implant shoulder in this group was placed more apically than nonsubmerged implants to allow primary flap closure. 6month bone loss, however, was similar in both the submerged and nonsubmerged groups. In the 612 month period the rate of bone loss in the R group decreased to mm while in the S group, in which second stage surgery was performed, it was higher ( mm). Interestingly, first year bone loss in the S group was slightly higher than in the R group despite a shorter exposure to the oral environment, corroborating Lorenzoni et al. (2003) who found that bone loss was lower in immediately restored vs. conventionally restored implants. Second stage surgery, accountable for 40% of initial bone loss (Weber et al. 1996) may partly explain this phenomenon. First year mean bone loss in the present study ranged between 1.19 and 1.88mm in the various study groups. This amount of bone loss corroborates results from some previous publications (Albrektsson et al. 1986; Payne et al. 2004). More specifically, De Bruyn (De Bruyn et al. 2001), in a study with similar loading groups, found an average marginal bone loss at 1 year of 1.6 mm, which is similar in magnitude to the present study. Results in the literature, however, vary widely. In view of these figures we interpret first year bone loss in the present study as slightly higher than in most reports. This may be the result of various parameters, most notably, the influence of the patients' periodontal disease history. The effect of this parameter on implant survival rates has been previously described (Karoussis et al. 2003, Evian et al. 2004, Hänggi et al ) and reviewed (van der Weijden et al. 2005) and may be the most significant factor affecting bone levels and not only survival rates. Conclusions First year bone level changes around immediately restored dental implants in periodontally susceptible patients were found to be slightly higher than most reports in the literature. This indicates a potential influence of periodontal susceptibility on the success rate of dental implants. Further long term studies and studies on larger cohorts are necessary to further investigate the relationship between periodontal disease and immediate restoration of dental implants. Acknowledgment This study was partly supported by a grant from MIS Implants Technologies Ltd. 1 MIS Implants Technologies Ltd. P.O.B. 110, Shlomi 22832, Israel. 2 Osstel Integration Diagnostic AB, Galmestadsvagen 3B, SE Goteborg, Sweden. 3 XCP film holder. Rinn. DENTSPLY International, York, PA, USA. 4 DiMAGE Scan Elite II, Konica Minolta Holdings Inc. Japan. 5 Virtual Measuring Tape. Tel Aviv, Israel. 6 Statview 512+, BrainPower Inc., Calabasas, CA. Table 3 Restored vs. NonRestored implants (Mean±SE) Table 4 Nonextraction vs. Extraction sites, comparison between groups (Mean ± SE) Variable Restored NonRestored P Variable Non Extr. Extr. P CBM Baseline 0.52± ± CBM Baseline 0.17± ± CBD Baseline 0.50± ± CBD Baseline 0.10± ± CB Baseline mean 0.52± ± CB Baseline mean 0.13± ± CBM 06m 0.87± ± CBM 06m 0.92± ± CBD 06m 1.09± ± CBD 06m 1.11± ± CB mean 06m 0.99± ± CB mean 06m 1.03± ± CBM 612m 0.27± ± CBM 612m 0.59± ± CBD 612m 0.32± ± CBD 612m 0.72± ± CB mean 612m 0.24± ± CB mean 612m 0.63± ± CBM 012m 1.19± ± CBM 012m 1.51± ± CBD 012m 1.33± ± CBD 012m 1.81± ± CB mean 012m 1.27± ± CB mean 012m 1.66± ±
18 4 Immediate implantation and immediate loading on lower incisors with MIS Dental Implant System TM. *A poster presented in the ICOI meeting, Jeju island
19 18 Immediate implantation and immediate loading on lower incisors with MIS Dental Implant System TM. Dueksang Jang *, DDS Immediate loading on root form titanium dental implants is a stilltodevelop field in implant dentistry. And yet, more articles support using this technique as time goes by. * Christmas Dentistry, Korea Initial drills to verify path and parallelism this time checking with xray is recommended. Two 3.3mm diameter and 16mm length BioCom (M.I.S.) implants were used in #32, #42 sockets. Straight body with slight apical tapering of the implant helps good primary stability. Right after installation, with mount still on check the path and depth again. 20Ncm of removal torque was achieved minimal requirement for immediate loading. The cervical position of the implant should be within the line connecting the labial surface of the adjacent teeth. Pickup type surgical impression was taken to record the fixture position. Healing caps were placed and the central incisor sockets were filled in with Bioplant HTR to reduce ridge resorption. Medical grade calcium sulfate barrier was applied on the central incisor sockets.
20 19 One of the prerequisites for immediate loading is adequate primary stability including at least 45Ncm of insertion torque, 20Ncm of removal torque, 65 of ISQ value, under minus 4 of periotest value, et cetra. Other recommendations for immediate loading could be the good quality of bone, enough length and diameter of implants, crossarch stabilization if possible, in case of opposing removable prosthesis, utilize temporary implants for immediate provisionals, aesthetic demand for upper anterior teeth, and so on. Lower incisor areas can be good candidates for immediate loading because of the usual type 1 or 2 quality of bone, the area usually has not so high occlusal forces applied, and the instant aesthetic demand is still high second to the upper anterior area. Immediate implantation right after tooth extraction is another field of interest which needs some technical challenges, including the difficulty to get an ideal path and position, lack of soft tissue covering, and it is not easy to achieve good primary stability. Immediate prosthesis can be a smart way to overcome the lack of soft tissue when the other technical difficulties related to immediate implantation have already been solved. Sutures were completed with simple interrupted and horizontal and vertical mattress sutures. An abutment was connected on next day of implant surgery and fastened with a 20Ncm torque controller. Immediate provisional restoration was cemented right after connecting the abutment, avoiding the cement remnants. Occlusal view after 10 weeks of implant surgery right before the cementation of the final prosthesis. Labial view of final ceramometal prosthesis in the centric occlusion. Standard radiograph of final prosthesis. Any questions to Dr. Dueksang Jang: