Two-stage IMZ implants and ITI implants inserted in a single-stage procedure. A prospective comparative study

The aim of this study was to evaluate the feasibility of using a two-stage implant system in a single-stage procedure and to study the impact of the microgap at crestal level and to monitor the microflora in the peri-implant area. Forty edentulous patients (Cawood & Howell class V-VI) participated in this study. After randomisation, 20 patients received two IMZ implants inserted in a single-stage procedure and 20 patients received two ITI implants. After 3 months, overdentures were fabricated, supported by a bar and clip attachment. A standardised clinical and radiographic evaluation was performed immediately after denture insertion and 6 and 12 months later. Twelve months after loading, peri-implant samples were collected with sterile paper points and analysed for the presence of putative periodontal pathogens using culture techniques. One IMZ implant was lost due to insufficient osseointegration. With regard to the clinical parameters at the 12 months evaluation, significant differences for plaque score and probing pocket depth (IMZ: mean 3.3 mm, ITI: mean 2.9 mm) were found between the two groups. The mean bone loss in the first year of functioning was 0.6 mm for both groups. Prevotella intermedia was detected more often in the ITI group (12 implants) than in the IMZ group (three implants). Porphyromonas gingivalis was found in three patients. In one of these patients an implant showed bone loss of 1.6 mm between T0 and T12. Some associations were found between clinical parameters and the target microorganisms in the ITI group. These associations were not present in the IMZ group. The short-term results indicate that two-stage implants inserted in a single-stage procedure may be as predictable as one-stage implants. The microgap at crestal level in nonsubmerged IMZ implants seems to have no adverse influence on the peri-implant microbiological colonisation and of crestal bone loss in the first year of functioning. The peri-implant sulcus can and does harbour potential periodontal pathogens without signs of peri-implantitis during the evaluation period of 1 year.     

Mandibular overdentures supported by two Brånemark, IMZ or ITI implants: a 5-year prospective study

OBJECTIVES: The aim of this prospective comparative study was to evaluate the survival rate and the condition of the peri-implant tissues of the IMZ implant system (two-stage cylindertype), the Br?nemark implant system (two-stage screwtype) and the ITI implant system (one-stage screwtype) supporting a mandibular overdenture during a 5-year follow-up period. MATERIAL AND METHODS: Three groups of 30 edentulous patients were treated with two endosseous implants in the interforaminal region of the mandible. Clinical and radiographic parameters were evaluated immediately after completion of the prosthetic treatment and after 1, 2, 3, 4 and 5 years of functional loading. RESULTS: The five-year survival rate is 98.3% for the IMZ group, 98.3% for the Br? group and 100% for the ITI group. Mean scores on indices for plaque, calculus, gingiva and bleeding were very low at all evaluation periods. Mean marginal bone loss over a period of 5 years, was 1.4 mm for the IMZ group, 0.7 mm for the Br? group and 0.9 mm for the ITI group. CONCLUSION: It is concluded that two implants placed in the interforaminal region, connected with a bar, supply a proper base for the support of a mandibular overdenture in the edentulous patient. After 5 years no clinically relevant and statistically significant radiographic changes had developed between the three implant systems.     

Clinical and radiologic evaluation of 2-stage IMZ implants placed in a single-stage procedure: 2-year results of a prospective comparative study

PURPOSE: The aim of this study was to evaluate the feasibility of using a 2-stage implant system in a single-stage procedure and to study the impact of the microgap between the implant and the abutment. MATERIALS AND METHODS: Sixty edentulous patients (Cawood class V or VI) participated in this study. After randomization, 20 patients received 2 IMZ implants placed in a single-stage procedure, 20 patients received 2 IMZ implants placed in the traditional 2-stage procedure, and 20 patients were treated with 2 ITI implants (single-stage procedure). The implants were placed in the canine area of the mandible. After 3 months, mandibular overdentures were fabricated, supported by a bar-and-clip attachment. A standardized clinical and radiographic evaluation was performed immediately after prosthesis placement and after 12 and 24 months. RESULTS: One IMZ implant of the 1-stage group and 1 IMZ implant of the 2-stage group were lost after 6 and 12 months, respectively. Apart from several significant but clinically irrelevant differences, the 3 groups did not appear to differ markedly with regard to clinical parameters during the evaluation period. The mean bone loss within the first 2 years of functioning (1.1 mm IMZ 1-stage, 0.8 mm IMZ 2-stage, 1.2 mm ITI) was comparable for the 3 groups. DISCUSSION AND CONCLUSIONS: The results of this study suggest that dental implants designed for a submerged implantation procedure can also be used in a single-stage procedure and may be as predictable as when the same implants used in a 2-stage procedure or as 1-stage implants. Placement of the microgap at the crestal level in 2-stage implants did not appear to have an adverse effect on the amount of peri-implant bone loss at 2 years in this study population.     

Mandibular overdentures supported by two Brånemark, IMZ or ITI implants: a ten-year prospective randomized study

Objectives: The aim of this prospective comparative study was to evaluate the survival rate, condition of peri-implant tissues, patient satisfaction and surgical and prosthetic aftercare of the IMZ-implant system (two-stage cylinder type), the Brånemark-implant system (two-stage screw type) and the ITI-implant system (one-stage screw type) supporting a mandibular overdenture during a 10-year follow-up period.
Materials and Methods: Three groups of 30 edentulous patients were treated with two endosseous implants in the interforaminal region of the mandible. Clinical and radiographic parameters were evaluated immediately after completion of the prosthetic treatment and after 1, 5 and 10 years of functional loading. Prosthetic and surgical aftercare was scored during the evaluation period, as well as patient satisfaction.
Results: The 10-year survival rate was 93% for the IMZ group, 98% for the Brånemark group and 100% for the ITI group (IMZ Conclusion: It is concluded that two implants placed in the interforaminal region, connected with a bar, supply a proper base for the support of a mandibular overdenture in the edentulous patient. After10 years, no relevant changes had developed between the three implant systems.     

Mandibular overdentures supported by two Brånemark, IMZ or ITI implants. A prospective comparative preliminary study: One‐year results.

The aim of this prospective comparative study was to evaluate the condition of the peri‐implant tissues of three different implant systems supporting a mandibular overdenture. Ninety edentulous patients (Cawood class V–VI) participated in this study. After randomization, 30 patients were treated with 2 Brånemark implants, 30 patients with 2 IMZ implants and 30 patients with 2 ITI implants. The implants were inserted in the canine region of the mandible. After 3 months overdentures were fabricated supported by a round bar and clip attachment. A standardized clinical and radiographic evaluation was performed 0,6 and 12 months after insertion of the denture. The intra‐oral radiographs were made, using the long‐cone technique with an aiming device. Two implants were lost (1 Brånemark, 1 IMZ) during the healing period. None of the patients showed any sensory change in lip or chin region. The pocket depth in the Brinemark group decreased significantly whereas the mucosa recession increased significantly in both the Brånemark as well as in the IMZ group. After 12 months, there was significantly less bone loss in the ITI group. From our study it was concluded that 2 (Brånemark, IMZ or ITI) implants placed in the interforaminal region connected with a bar supply a proper base for the support of a mandibular overdenture in the (Cawood V–VI) edentulous patient. The ITI implant appears to be the implant of choice for mandibular overdenture therapy. because only one operation is required for a comparable result.     

Mandibular overdentures supported by two Brånemark,IMZ or ITI implants. A prospective comparative preliminary study: One-year results.

The aim of this prospective comparative study was to evaluate the condition of the peri-implant tissues of three different implant systems supporting a mandibular overdenture. Ninety edentulous patients (Cawood class V–VI) participated in this study. After randomization, 30 patients were treated with 2 Brånemark implants, 30 patients with 2 IMZ implants and 30 patients with 2 ITI implants. The implants were inserted in the canine region of the mandible. After 3 months overdentures were fabricated supported by a round bar and clip attachment. A standardized clinical and radiographic evaluation was performed 0,6 and 12 months after insertion of the denture. The intra-oral radiographs were made, using the long-cone technique with an aiming device. Two implants were lost (1 Brånemark, 1 IMZ) during the healing period. None of the patients showed any sensory change in lip or chin region. The pocket depth in the Brinemark group decreased significantly whereas the mucosa recession increased significantly in both the Brånemark as well as in the IMZ group. After 12 months, there was significantly less bone loss in the ITI group. From our study it was concluded that 2 (Brånemark, IMZ or ITI) implants placed in the interforaminal region connected with a bar supply a proper base for the support of a mandibular overdenture in the (Cawood V–VI) edentulous patient. The ITI implant appears to be the implant of choice for mandibular overdenture therapy. because only one operation is required for a comparable result.     

Present status of immediate loading of oral implants

PROBLEM: Several conditions must be present to obtain implant integration and long-term clinical success when using the one-stage implant placement procedure with immediate loading. These conditions include (1) primary stability, (2) sufficient bone quality, and (3) elimination of micromovement of the implant before osseous integration is complete. PURPOSE: This report presents the results of research on immediate loading using a new and innovative implant design, Ankylos. METHODS: The author reviewed clinical studies of immediate loaading or oral implants, including two treatment options, removable overdentures and fixed reconstructions. RESULTS: Animal studies have demonstrated that successful osseointegration of Ankylos implants can occur (Figure 2D) when implants are placed and loaded immediately in the presence of some specific conditions. The histological findings involving implants that were placed in humans and immediately loaded showed no fibrous tissue formation (encapsulation). The bone-to-implant contact (osseointegration) was found to be excellent between the immediately-loaded implants and the surrounding alveolar bone. CONCLUSION: The Ankylos implant system with its progressive thread design successfully promotes primary, clinical stability at the time of implant placement. Several animal studies have shown that in implant restorations placed in similar areas of poor bone quality (ie, maxilla and the posterior part of the mandible), the concept of immediate loading can result in long-term clinical success, when loading forces are controlled. Immobilization of the implants and soft diet recommendations that reduce micromovement at the bone-to-implant interface will improve long-term clinical success. In summary, the Ankylos implant is well designed for one-stage placement with immediate loading, as well as for two-stage treatment protocols. Both clinical protocols will result in long-term clinical survival.     

愈合期埋植型和非埋植型种植体周围牙槽骨吸收情况观察

目的：观察比较愈合期两段式埋植型和非埋植型种植体周围牙槽骨吸收情况是否存在差异。方法：收集种植义齿修复下颌后牙区牙体缺损患者44例共94颗,其中54颗两段式埋植型Frialit-2种植体和40颗两段式非埋植型ITI种植体,根据种植体植入术后和愈合后数字化全景X线片来进行种植体周围牙槽骨高度的测量。结果：显示愈合期两段式埋植型Frialit-2种植体和非埋植型ITI种植体周围骨吸收值不存在统计学差异（p=0．667〉0．05）。结论：在本实验条件下,愈合期埋植型和非埋植型种植体周围牙槽骨骨吸收改变与种植体的植入方式无关。     

Osseointegration of Brånemark fixtures using a single‐step operating technique. A preliminary prospective one‐year study in the edentulous mandible.

The aim of the present prospective clinical study was to analyze the feasibility of inserting Brånemark fixtures according to a one-stage procedure including transmucosal healing and to subsequently evaluate the predictability of osseointegration as well as the potential of such implants for stabilizing complete overdentures in the edentulous mandible. Five patients (2 women, 3 men), completely edentulous in the mandible and with a mean age of 60 years, volunteered for this study. Two fixtures of various length Lpar;10–20 mm) and 3.75 mm in diameter were inserted in the lower canine regions. A standard surgical procedure including a mid-crestal incision was used. After the placement of the fixtures, healing abutments, which are normally used during second-stage surgery, were inserted instead of the usual cover screws. Three months after implant placement a clinical and radiographic examination was performed to confirm the presence or absence of osseointegration of the fixtures prior to exchanging the healing abutments with the spherical attachments. Finally, different clinical (Plaque Index, Bleeding Index, probing depth, Periotest® mobility) and radiographic (bone loss, peri-implant radiolucency) parameters were recorded 9 months after loading of the fixtures by means of a complete mandibular overdenture, retained by two ball attachments in the canine regions. All fixtures were perfectly stable (mean Periotest values of ?2) and presented favorable peri-implant soft tissue conditions, and no patient was complaining about any particular symptom. As far as retention and stability of their implant supported overdenture was concerned, the participants without exception considered the therapeutic result as being perfectly adequate. The evaluation of the radiographic analysis showed a similar initial bone loss rate as reported in the literature for a submerged surgical procedure. Therefore, within the specific limits of this study. it may be concluded that Brånemark fixtures can be inserted using a single-step surgical protocol predictably leading to successful osseointegration and subsequently provide similar peri-implant results as reported for the traditional two stage technique. However, a longer period of observation as well as a more significant number of cases will be necessary to confirm these promising preliminary data.     

Submerged or non-submerged healing of endosseous implants to be used in the rehabilitation of partially dentate patients

OBJECTIVE: To evaluate bone-level alterations that occurred at implants of the Astra Tech(R) System that were placed in the load carrying, posterior parts of the dentition using either a submerged (two-stage) or a non-submerged (one-stage) installation protocol. MATERIAL AND METHODS: Eighty-four patients that required 115 fixed partial dentures (FPDs or cases) entered the prospective study. All subjects were assigned one patient and > or =one case numbers. For the randomization of cases, a custom-made program based on balanced random permuted blocks was utilized. The cases were assigned to two treatment groups, namely one-stage installation procedure, non-submerged technique (group A) and two-stage installation procedure, submerged technique (group B). Several subjects contributed with cases to both groups A and B. Periodontal, endodontal and open caries lesions were treated prior to implant installation. All patients received careful oral hygiene instruction and training in self-performed plaque control measures. The surgical technique used for fixture installation followed the outline described in the manual for the Astra Tech System. The FPDs were placed 3 months (mandible) and 6 months (maxilla) following implant installation. Immediately following FPD placement, a baseline examination was performed that included assessment of plaque, soft-tissue inflammation and bone level. Clinicians who were otherwise not involved in the study performed the radiographic measurements. Clinical and radiographical examinations were repeated once a year after the baseline examination. DATA ANALYSIS: The primary outcome variable was the change in the bone level at the implants from the time of placement of the bridge (FPD) to the 1- and 2-year reexaminations. Fisher's permutation test was used to test if differences existed between groups A and B, and between patients (men/women, smokers/non-smokers, age), sites (maxilla/mandible) and implants (length, diameter). Pitman's test was used to study correlations between bone shape and quality data and different radiographic bone-level data. RESULTS: It was demonstrated that tissue healing following implant installation appeared to be independent of the surgical protocol, i.e. whether the marginal portions of the implants during surgery were fully or only partly submerged under the ridge mucosa. Thus, (i) in both treatment groups the number of implants that failed to osseointegrate (early failures) was small (<2%); (ii) at the end of the recommended periods of bone healing prior to loading, - in both groups, maxilla=6 months and mandible=3 months - the level of the marginal bone was close to the coronal rim of the fixture; group A: 1.54+/-0.92 mm, group B: 1.31+/-0.77 mm. The current study also demonstrated that irrespective of surgical protocol (two-stage, one-stage), implants supporting the FPDs exhibited only small amount of radiographic bone loss during the first year of function (group A: 0.02+/-038 mm, group B: 0.17+/-0.64 mm). Moreover, during the second year of function, the amount of additional bone loss that occurred in the two treatment groups was close to zero. CONCLUSION: Periimplant bone-level change during function seemed to be unrelated to whether initial soft- and hard-tissue healing following implant installation had occurred under submerged or non-submerged conditions.     

Two-part implants inserted in a one-stage or a two-stage procedure. A prospective comparative study

OBJECTIVE: The aim of this study was to evaluate the feasibility of using a two-part implant system in a one-stage procedure and to monitor the microflora in the peri-implant area in relation to clinical and radiographic outcome. MATERIAL AND METHODS: After randomisation, 40 edentulous patients (Cawood & Howell class V-VI) received two IMZ implants in the anterior mandible inserted by either a one-stage (n = 20) or a two-stage (n = 20) surgical procedure for overdenture treatment. A standardised clinical and radiographic evaluation was performed after denture insertion as well as 6 and 12 months thereafter. Twelve months after loading, peri-implant samples were collected and analysed for the presence of putative periodontal pathogens using culture technique. RESULTS: No striking differences were found between the two groups with regard to the clinical parameters during the evaluation period. The mean bone loss in the first year of functioning was 0.6 mm in both groups. With regard to the gingiva score, plaque score, bleeding score or bone loss between T0 and T12, no associations were found with the presence of the cultured microorganisms. An association was present between pockets >or= 4 mm and the presence of Peptostreptococcus micros in the two-stage group. CONCLUSIONS: The short-term results indicate that two-part implants inserted in a one-stage procedure may be as predictable as inserted in the common two-stage procedure. The peri-implant sulcus can and does harbour potential periodontal pathogens without significant signs of tissue breakdown.     

Tissue integration of non‐submerged implants. l‐year results of a prospective study with 100 ITI hollow‐cylinder and hollow‐screw implants.

It has been postulated that the wound healing in a closed submerged location is one of the prerequisites for osseointegration of dental implants. The purpose of the present study was to evaluate the tissue integration of intentionally non-submerged titanium implants inserted by a one-stage surgical procedure. 100 ITI implants were consecutively placed in 70 partially edentulous patients. After a healing period free of masticatory loading for at least 3 months, the implants were examined. The clinical status showed for all implants neither detectable mobility nor signs of a peri-implant infection. Therefore, prosthetic abutments were inserted, and the patients were restored with fixed partial dentures. All patients were regularly recalled at 3-month intervals, and no patient dropped out of the study. Thus, all 100 implants were re-evaluated 12 months following implantation. Plaque- and sulcus bleeding indices, probing depth, clinical attachment level, width of keratinized mucosa, and periotest scores were assessed. In addition, standardized radiographs were analyzed for the presence of peri-implant radiolucencies and for the location of alveolar bone levels around the implants. Based on predefined criteria, the implants were classified as successful or failing. 98 implants were considered successful, and 1 implant failing. The remaining implant exhibited a peri-implant infection requiring local and systemic antimicrobial treatment. The results of this short-term study indicate that intentionally non-submerged ITI implants yield a high predictability for successful tissue integration.     

Treatment of edentulism using Astra Tech implants and ball abutments to retain mandibular overdentures.

The goal of this study was to provide evidence to support simplified treatment of mandibular edentulism using denture fabrication and implant placement to circumvent the need for second-stage surgeries or prosthodontic superstructures. A 5-year prospective clinical trial is reported, which involved treatment of mandibular edentulism using the single-stage surgical placement of a TiOblast microthreaded titanium screw implant with immediate replacement of a relieved mandibular overdenture and eventual retention of the overdenture with reduced ball abutments. Fifty-eight patients were treated; 116 implants were placed using a single-stage surgical approach, with a duplicate mandibular denture as the tomographic/surgical template. Mandibular dentures were relieved and relined with a tissue conditioning material and placed immediately after implant surgery. After 3 months, Conical Seal Design ball abutments were placed and attachments were secured in the overdentures by heat-polymerizing laboratory reline methods. Five of the 116 consecutively placed implants failed at 2 to 4 months, providing an immediate implant survival rate of 95.69% at the time of attachment connection. Pain and inflammation were not common to all failures, and infection was not reported in any of the 5 failures. The immediate placement of implants by a single-stage surgical procedure in the parasymphyseal region of the mandible, followed by placement of a relined mandibular denture, results in predictable and asymptomatic healing of implants that display the clinical and radiographic features of osseointegration. Encouraging results at the immediate observation period (attachment connection) must be tempered by the need for prudent and detailed clinical and radiologic evaluation over the 5-year trial period.     

Is the osseointegration of immediately and delayed loaded implants the same?—comparison of the implant stability during a 3‐month healing period in a prospective study

Objectives: The objectives of the present study were (1) to compare the stability of delayed loaded (DL) and immediately loaded (IL) ITI SLA implants during the first 3 months of the healing period using resonance frequency analysis (RFA) and (2) to determine the factors that affect implant stability during the healing period.
Materials and methods: To compare implant stability, RFA was performed on two groups of patients (12 patients received 25 IL implants and 47 patients received 79 DL implants) with a total 104 ITI SLA implants. Implant stability was measured directly by RFA at implant placement and consecutively once a week for 12 weeks. Statistical analyses were carried out to study implant stability differences between IL and DL groups.
Results: One of the 25 implants in the IL group failed, and no implant was lost in the DL group. Implant stability between the IL and DL groups showed a statistically significant difference ( P <0.05). The mean implant stability quotient of all measured implants from implant insertion to 12 weeks was 72.88 ± 5.39 for the DL and 75.86 ± 3.60 for the IL types. The lowest stability was at 4 weeks for DL implants (mean: 71.58 ± 5.11) and 2 weeks for IL implants (mean: 71.33 ± 2.97). In both groups, bone types I and II showed higher implant stability than bone type III ( P <0.05).
Conclusions: The findings of this study indicate that differences in osseointegration between IL and DL implants may be predicted according to differential implant stability.     

Localized ridge augmentation using a micro titanium mesh: a report on 27 implants followed from 1 to 3 vears after functional loading

The present paper describes the clinical and radiographic healing results of 27 implants followed from 1 to 3 years after functional implant loading. Prior to implant placement, alveolar ridges with insufficient bone volume were augmented using autogenous bone grafts and a micro titanium mesh for graft stabilization. After a mean interval of 5.2 months implants were installed. Following an osseointegration period of on average 7.2 months, implants were supplied with suprastructures. The mean loading period for the 27 implants was 21 months. All implants exhibited ankylotic stability and healthy peri‐implant soft tissues. The detailed analysis of clinical parameters (probing depth, level of mucosal margin, attachment level, modified plaque and sulcus bleeding indices) and radiographic measurements (crestal bone level), revealed findings similar to those at implants placed into non‐augmented bone. Peri‐implant bone resorption was calculated to be 1.0 mm for the 1st year after implant loading and 0.1 mm for the following year. Pain, suppuration or semilunar bone defects were absent at all implants. It was concluded that loaded dental implants which have been inserted into an augmented alveolar ridge using autogenous bone grafts and a micro titanium mesh for graft stabilization, demonstrate clinical and radiographic findings similar to those of implants placed into a pristine ridge.     

Early loading (2 or 6 weeks) of sandblasted and acid-etched (SLA) ITI implants in the posterior mandible. A 1-year randomized controlled clinical trial

The aim of this 1-year prospective controlled clinical trial was to evaluate the effect of early loading of ITI solid screw titanium implants with a sandblasted and acid-etched (SLA) surface on clinical and radiographic parameters. MATERIAL AND METHODS: Twenty-seven consecutively admitted patients presenting bilateral edentulous posterior mandibular areas and in need of prosthetic reconstruction were recruited. Sixty-seven ITI standard solid screw implants with an SLA surface, a diameter of 4.1 mm and a length of 8, 10 or 12 mm were installed bilaterally in molar and premolar areas according to a one-stage surgical protocol. One week (test) and 5 weeks (control) after implant placement, solid ITI prosthetic abutments were connected using a torque of 35 N cm. No provisional restoration was fabricated. Two weeks (test) and 6 weeks (control) after implant placement, porcelain-fused-to-metal single-tooth crowns were cemented. Clinical measurements were obtained at day 0 and 2, 6, 12, 24 and 52 weeks thereafter. Periapical radiographs were taken immediately after implant placement, after 6 weeks and at the 1-year examination. RESULTS: After 1 year, implant survival was 100%. Two test and one control implants rotated at the time of abutment connection and were left unloaded for 12 additional weeks. At the 1-year examination, no statistically significant differences were found between the test and control sites with respect to pocket probing depths (2.6 mm +/- 0.5 vs. 2.7 mm +/- 0.5), mean clinical attachment levels (3.1 mm +/- 0.4 vs. 3.2 mm +/- 0.5), mean percentages of sites bleeding on probing (9.7% vs. 8.3%), mean widths of keratinized mucosa (1.8 mm +/- 0.4 vs. 1.9 mm +/- 0.5), mean PerioTest values (-1.4 PTV +/- 0.9 vs. -1.6 PTV +/- 0.8) or mean crestal bone loss measurements (0.57 mm +/- 0.49 vs. 0.72 mm +/- 0.50). CONCLUSION: Based on these results, loading of titanium implants with an SLA surface as early as 2 weeks did not appear to jeopardize the osseointegration healing process in the posterior mandible. Furthermore, implants rotating at 35 N cm, if left unloaded for additional 12 weeks, did not negatively affect clinical and radiographic outcomes.     

Implant stability measurement of delayed and immediately loaded implants during healing

The purpose of the present study was (1) to measure the primary stability of ITI implants placed in both jaws and determine the factors that affect the implant stability quotient (ISQ) determined by the resonance frequency method and (2) to monitor implant stability during the first 3 months of healing and evaluate any difference between immediately loaded (IL) implants and standard delayed loaded (DL) implants. The IL and DL groups consisted of 18 patients/63 implants and 18 patients/43 implants. IL implants were loaded after 2 days; DL implants were left to heal according to the one-stage procedure. The ISQ was recorded with an Osstell apparatus (Integration Diagnostics AB, Gothenburg, Sweden) at implant placement, after 1, 2, 4, 6, 8, 10 and 12 weeks. Primary stability was affected by the jaw and the bone type. The ISQ was higher in the mandible (59.8+/-6.7) than the maxilla (55.0+/-6.8). The ISQ was significantly higher in type I bone (62.8+/-7.2) than in type III bone (56.0+/-7.8). The implant position, implant length, implant diameter and implant deepening (esthetic plus implants) did not affect primary stability. After 3 months, the gain in stability was higher in the mandible than in the maxilla. The influence of bone type was leveled off and bone quality did not affect implant stability. The resonance-frequency analysis method did not reveal any difference in implant stability between the IL and DL implants over the healing period. Implant stability remained constant or increased slightly during the first 4-6 weeks and then increased more markedly. One DL and IL implant failed; both were 8 mm long placed in type III bone. At the 1-year control, the survival rate of the IL and the DL implants was 98.4% and 97.7%, respectively. This study showed no difference in implant stability between the IL and DL procedures over the first 3 months. IL short-span bridges placed in the posterior region and full arch rehabilitation of the maxilla with ITI sandblasted-and-etched implants were highly predictable.     

Immediate function of cortically anchored disk-design implants without bone augmentation in moderately to severely resorbed completely edentulous maxillae.

The completely edentulous maxilla remains a challenge in implant dentistry. Conventional two-stage surgical techniques require two independent invasive surgeries separated by a 5-6-month healing period. In addition, an increased risk of trauma to the implant-bone interface may be caused by a removable transitional complete denture during the interim submerged period, which can compromise implant success or increase crestal bone loss around the implants during initial bone healing. The purpose of this clinical trial was to evaluate the safety and efficacy of immediately loading a fixed implant-supported prosthesis without bone augmentation in moderately to severely resorbed, completely edentulous maxillae. Over a 41-month period, 783 titanium implants (627 laterally inserted disk implants, with or without 156 axially inserted Structure implants) were placed in 72 consecutive patients with completely edentulous maxillae using an immediate loading protocol. After 6 months of function, the fixed restorations were removed and each implant status was verified using radiographs, Periotest evaluations, clinical osseointegration criteria, and torque testing at 20 N-cm. Six months postoperatively, 98% of the implants were radiologically and clinically osseointegrated. Fifty-six gold screws (7%) required retightening after 10 months, but no screw fractures occurred during this study period. The postrestorative follow-up of these patients ranged from 6 to 48 months. As of this report, all of the fixed prostheses remain functional, and no additional implants have been lost. This clinical trial demonstrates that immediate loading of nonsubmerged, laterally inserted disk-design implants may provide adequate primary anchorage and longterm osseointegration in completely edentulous maxillae. The initial multicortical anchorage afforded by the disk-design implant in this study, coupled with biomechanical splinting of the disks (sometimes with more traditional root-form design implants) using a rigid prosthesis, permits a one-stage predictable implant procedure offering rapid restoration of patients to masticatory function.     

Clinical and radiological results of patients treated with three treatment modalities for overdentures on implants of the ITI® Dental Implant System. A randomized controlled clinical trial.

In a randomized controlled clinical trial carried out at the Ignatius teaching hospital in Breda, The Netherlands, 110 edentulous patients with severe mandibular bone loss were treated with implants of the ITI Dental Implant System using 3 different treatment strategies: a mandibular overdenture supported by either 2 implants with ball attachments, 2 implants with an interconnecting bar, or by 4 interconnected implants. In this study, results of clinical and radiographic parameters were evaluated and compared over a period of 19 months after implant placement. A total of 283 ITI Dental Implants were placed. Six implants (2%) were lost during the osseointegration period. No further implant losses occurred after that. At the 19 month evaluation mean values and standard deviations for bleeding index were 0.51 +/- 0.5 (bleeding incidence = 70%) and for plaque index they were 0.46 +/- 0.5 (plaque incidence = 45%). The mean values and standard deviations for probing depth and loss of attachment were 2.7 +/- 1.1 mm and 0.26 +/- 0.6 mm respectively. The radiographic evaluation showed a mean bone loss of 1.5 mm +/- 0.26 after 19 months for all the implants. In cases with 4 interconnected implants there was significantly more bone loss around the central 2 implants (2.1 +/- 0.31 mm) in comparison with the lateral 2 (1.4 +/- 0.25 mm). No significant correlations were found between plaque and bleeding indices and bone loss.     

Early loading of nonsubmerged titanium implants with a sandblasted and acid-etched (SLA) surface: 3-year results of a prospective study in partially edentulous patients

PURPOSE: The aim of this study was to evaluate the success rate of ITI implants with the SLA surface that were loaded after 6 weeks of healing. MATERIALS AND METHODS: In this prospective cohort study, a total of 104 implants were placed in posterior sites of 51 partially edentulous patients exhibiting bone densities of Class 1, 2, or 3. After a healing period of 6 weeks, all implants were functionally loaded with cemented crowns or fixed partial dentures. The patients were recalled at 3, 12, 24, and 36 months for clinical and radiographic examination. RESULTS: One implant failed to integrate during healing, and 1 implant was lost to follow-up and considered a dropout. The remaining 102 implants showed favorable clinical and radiographic findings and were considered successfully integrated at the 3-year examination. This resulted in a 3-year success rate of 99.03%. DISCUSSION: The peri-implant soft tissues were stable over time, as evidenced by no changes in the mean probing depths and the mean attachment levels during the follow-up period. None of the radiographs exhibited signs of continuous peri-implant radiolucency, which confirmed ankylotic stability of all 102 implants. The radiographic evaluation of the bone level at the implant indicated stability of the bone crest levels. CONCLUSION: The results of this prospective study demonstrated that early loading of ITI implants with the SLA surface after an unloaded healing period of 6 weeks provided successful tissue integration with high predictability, and that successful tissue integration was well maintained up to 3 years of follow-up in this study population.