Bücher und Digitale Medien

The aim of this paper is to report on three patients who received unconventional implant treatment because of the presence of impacted teeth. To avoid invasive surgical removal of the impacted teeth and delayed implant treatment, implants were placed through the impacted teeth. Of the seven implants placed into four impacted teeth, all healed uneventfully except a short (8.5-mm) implant that became mobile after 4 months. One and three implants now have been loaded for 3.5 and 2 years, respectively. The two other implants were removed after 6 months of uneventful healing. These cases, although limited in number, suggest that implant placement through an impacted tooth might not interfere with implant integration or harm occlusal function, at least in the short term. More study is warranted before this unconventional procedure might be considered as a possible clinical option when, at an impacted tooth site, clinicians seek to avoid invasive surgery.

The application of immediate loading of implants in the edentulous maxilla in multiple-risk patients is presented. Five partially edentulous patients attended with failing prostheses supported by hopeless teeth. An immediate-loading protocol was proposed because the patients rejected provisionalization with a removable prosthesis. Multiple teeth were extracted, and 44 immediately loaded implants were placed, most of them (55.5% to 88.9%) in fresh extraction sites, to support a cross-arch prosthesis that was loaded 3 to 4 days after surgery. The overall implant failure rate was 13.4%; in healed sites it was 20% (2/10) and in fresh extraction sites it was 8.82% (3/34). Prosthetic success was 100%. The overall failure rate was higher than is usually seen with the standard delayed-loading approach. Nevertheless, this immediate-loading protocol was satisfactory for the patients and the practitioner because prosthetic success was maintained during the provisionalization phase.

Purpose: This article provides preliminary clinical results on the Osseotite NT implant, which was developed to simplify surgical procedure and cover an extended range of indications. Placement characteristics of NT and standard Osseotite implants were also compared in an in vitro study. Materials and Methods: The in vitro placement characteristics of NT and standard Osseotite implants of 4.0 mm diameter and 8.5 to 15 mm in length were compared. In addition, a total of 182 NT implants (96 maxillary and 86 mandibular) were placed in 92 patients; of these, 87.9% were placed using a 1-stage technique. The implants were placed in healed sites (43.9%), fresh extraction sockets (37.4%), or recent extraction sites (2 months postextraction) (18.7%). Before restoration, healing times of 3 to 4 months in the mandible and 5 to 6 months in the maxilla were allowed. The entered implant length in the osteotomy site before contacting the bony walls (EILOS) was compared, as well as the number of turns and the time required to seat the implants. Cumulative survival rates (CSRs) were calculated for up to 18 months of follow-up after surgery. Results: The EILOS was between 47.3% and 57.6% of implant length for the NT implants; for the standard implants, it was between 12.0% and 21.2%. With the NT implants, the number of turns and the placement time were reduced by 61% to 64% and 61% to 65%, respectively. In the clinical study, 4 implants failed during the healing period; none failed after prosthesis placement. The CSR was 97.79% for implants placed into fresh or recent extraction sites; in healed sites, the CSR was 98.75%. The cumulative prosthetic success rate was 100%. Discussion: This new implant design is seated with special drills; the drilling sequence requires less time and less torque than that used for standard implants. The low failure rate after prosthetic loading was consistent with that observed for standard Osseotite implants. Conclusion: These preliminary data suggest that the NT implant can be predictable in healed sites and fresh or relatively recent extraction sockets.

Purpose: The purpose of this prospective multicenter study was to evaluate the efficacy of 3i threaded implants for the treatment of edentulous patients in a 1- to 5-year period. This article reports the total data and global results of 3 threaded designs of 3i implants: self-tapping, ICE, and Osseotite. Materials and Methods: A total of 1,583 implants (619 ICE, 545 Osseotite, and 419 self-tapping) were placed between 1995 and 1999 in 528 patients at 13 European clinical centers. The average age of the patients was 53.6 years. Clinical and radiographic evaluations were performed annually for up to 5 years. Results: Of the total implants, 707 were placed in the maxilla and 876 in the mandible. A total of 1,162 implants were placed in posterior segments. Forty-eight implants were lost to follow-up and 55 were failures. The most frequent prosthetic indication was the short-span fixed prosthesis (440 cases), followed by 172 single-tooth replacements, 56 long-span prostheses, and 4 overdentures. Radiographic evaluation after 6, 12, and 24 months of implant loading showed, respectively, mean crestal bone loss of 0.04 ± 1.3 mm, 0.12 ± 1.6 mm, and 0.2 ± 1.7 mm. A cumulative survival rate of 96.5% was observed 5 years after implant placement, with 97.2% survival in the maxilla and 95.8% in the mandible. The survival rate was similar in anterior (96.7%) and posterior (96.5%) segments. Discussion: A total of 55 failures were reported in this study with 47 early failures and 8 late failures. The rate of late failures is of utmost importance for the restorative dentist. Conclusion: This clinical study gives evidence of very high success rates using 3 threaded designs of 3i implants.

Patients who have been partially edentulous in the posterior segments for many years frequently present with reduced alveolar bone and/or enlarged sinuses. The choice of treatment for these patients will depend on the volume of residual bone, morphology of the alveolar crest, and amount of space available for the prosthesis. A new, minimally invasive surgical procedure using Summers osteotomes is described for the treatment of the edentulous posterior maxilla in which the bone thickness below the sinus is limited (¡Ý 5 mm). This suggested modified treatment is based on the use of a combination of osteotomes, drills, and screw-type implants with a rough surface texture.

At the end of the 1980s, it was suggested that wide-diameter implants be used to better the prognosis in cases in which the condition of the supporting bone is unfavorable. Technical improvements associated with different shapes and materials used for implants have led to an evolution of our concepts of surgical and prosthetic treatments. The aim of these new suggestions is to optimize the functional and esthetic result while respecting the fundamental principles of osseointegration. Up to the present time, very few studies have been published on wide-diameter implants. However, the short- and medium-term results that have been reported have been very satisfactory.

This multicenter prospective clinical evaluation was undertaken to determine the therapeutic success and marginal bone level stability of 3is self-tapping and ICE implants after 3 years of prosthetic loading. Between July 1995 and June 1996, 189 completely or partially edentulous patients were treated with 614 machined-surface screw-type commercially pure titanium implants (self-tapping or ICE). Two hundred seventy-seven self-tapping implants were placed in 85 patients (average age of 56 years), and 337 ICE implants were placed in 104 patients (average age of 61 years). A total of 360 implants (58.6%) were placed in posterior segments. Easier placement was reported with the ICE implant in normal or dense bone. For the self-tapping implants, survival rates of 92.9% and 91.6% were noted after 1 and 3 years of prosthetic loading, respectively. Survival rates of 95.4% and 93.8% were obtained with the ICE implant for the same periods. Late failures (after loading) were more common than early failures (before loading) for both types of implants. The marginal bone level of 238 self-tapping implants (85.9%) and of 307 ICE implants (91%) was radiographically evaluated at 3 years. Marginal bone level was at the first thread for 95.1% of implants. A loss of marginal bone level of 2 to 4 threads was noted for 4.9% of the evaluated implants. No implant showed bone loss greater than the fourth thread. Overall survival rates of 94.3% and 92.9% were obtained after 1 and 3 years of prosthetic loading, respectively, for 596 and 588 implants. Schlagwörter: bone density, clinical trials, dental implants, multicenter study, self-tapping dental implants

The conventional placement protocol for submerged and non-submerged implants was proposed in the 1960s and 1970s. Multicenter studies have reported satisfactory success rates for both protocols and a similar loss of crestal peri-implant bone after implant loading (0.5 to 1.5 mm). In recent years, placement of submerged implants using a single surgical procedure was introduced, with the immediate placement of a healing abutment. Some studies reported good short-term results using this approach. Recently, a supracrestal apical-coronal positioning of the implant collar has been proposed for posterior sectors using submerged implants. This positioning facilitates the second surgical phase, as well as fabrication of the prosthetic restoration, and limits the amount of crestal bone loss. Schlagwörter: bone resorption, dental implants, endosseous dental implantation, preprosthetic oral surgical procedures

The longevity of teeth depends directly on the state of the periodontal tissues. Many etiologic factors can lead to the loss of a tooth. Tooth loss is frequently associated with bone resorption. The diagnosis of a condition and knowledge of its etiology are essential to assess the prognosis of the remaining teeth and to formulate the correct treatment plan. Many parameters must be investigated to ascertain an accurate diagnosis. An understanding of the patient's needs and the length and likely success of treatment guides the decision of whether to preserve teeth or extract them and place implants. Advanced periodontitis poses a major therapeutic dilemma. Judicious, strategic extractions may permit the placement of long implants in ideal positions.