Prevention of intrusion of natural teeth surrounded by freestanding implants.

Intrusion is frequently observed as a complication associated with tooth-implant-supported prostheses: the natural tooth that serves as an abutment moves apically and out of occlusion. However, intrusion of teeth proximal to implants has yet to be reported in the literature. In this manuscript, three presentations of tooth intrusion proximal to implants are reported; potential causes of the phenomenon are discussed; and a potential treatment for patients experiencing this condition is presented. Intrusion of teeth surrounded by freestanding implants is a rare phenomenon, a cause of which may be excessively tight proximal contacts that are below the height of contour of adjacent implants. Alleviating these contacts enables the intruded tooth to erupt back and should be considered a viable treatment option.

Use of a Resin-Bonded Bridge to Replace a Congenitally Missing Lateral Incisor: Treatment of "Intrusion" of Teeth.

Craniofacial growth is an important factor to consider when providing dental implant treatment for adolescents to replace missing teeth. Ongoing longitudinal observation has demonstrated that such tooth replacements may appear intruded over time, because there may be ongoing downward and anterior movement of both the alveolus and the teeth at a rate exceeding that of the dental implant, which acts like an ankylosed unit. This case reports on a 23.5-year-old female patient who, at age 16, had orthodontics completed and was left with a space where the maxillary right lateral incisor was congenitally missing with the hope of future restoration with a dental implant. A resin-bonded bridge had been placed to fill the space in the interim. After approximately 7.5 years, the bridge loosened and the patient sought an implant option as its replacement. Clinical images revealed that the bridge, which contained two bonded wings, may have limited physiologic growth, causing both the maxillary right central incisor and canine to appear intruded compared with the left central incisor and canine. This case illustrates, at the very least, that growth and development may not be complete in females aged 16 years and that the way in which a missing tooth is replaced must be carefully considered given the impact that ongoing growth and development may have on restorative care. Moreover, further growth and development may also impact adults.

Bone regeneration around immediate implants utilizing a dense polytetrafluoroethylene membrane without primary closure: a report of 3 cases.

Case reports document successful use of a high-density polytetrafluorethylene membrane to augment horizontal defects associated with immediately placed implants. This membrane, which is designed to withstand exposure (not require primary closure) to the oral cavity because it is impervious to bacteria, reduces the need for advanced flap management to attain primary closure. Thus, the surgical aspect is less complex and the mucogingival architecture of the area can be maintained. These cases demonstrate successful use of this application and provide evidence for controlled clinical trials to further evaluate this technique.

A prospective, multicenter, randomized-controlled 5-year study of hybrid and fully etched implants for the incidence of peri-implantitis.

BACKGROUND: The dual acid-etched (DAE) implant was commercially introduced in 1996 with a hybrid design incorporating a machined surface in the coronal region from approximately the third thread to the seating surface. This design was intended to reduce the risks of peri-implantitis and other related soft tissue complications that were reported for implants with surface roughness in the coronal region. The objective of this prospective, randomized-controlled clinical trial was to determine the incidence of peri-implantitis for a fully etched implant with the DAE surface extending to the implant platform. METHODS: Patients had implant sites randomly assigned to receive one hybrid control implant and at least one fully etched test implant in support of a short-span fixed restoration to ensure that variables (e.g., demographics, jaw locations, and bone density) were consistent between groups. Prostheses were inserted 2 months after implant placement with follow-up evaluations scheduled annually for 5 years to assess mucosal health based on bleeding on probing, suppuration, and probing depths. Evaluations also included radiographic and mobility assessments. RESULTS: One hundred twelve patients who were enrolled at seven centers received 139 control and 165 test implants (total: 304 implants). With >5 years of postloading evaluations, there was one declaration of peri-implantitis associated with a control implant that was successfully treated later. Clinical probing and radiographic assessments did not reveal differences between groups in mucosal health outcomes or other signs of peri-implantitis. CONCLUSION: Five-year results of this randomized-controlled study showed no increased risk of peri-implantitis for fully etched implants compared to hybrid-designed implants.

Early loading of Osseotite implants 2 months after placement in the maxilla and mandible: a 5-year report.

PURPOSE: In this multicenter study, the performance of Osseotite implants after a 1-stage surgery and abbreviated healing period of 2 months is reported. The implants were followed for up to 5 years. MATERIALS AND METHODS: Partially or completely edentulous patients treated at 10 private practice centers were included in the study. Oral hygiene was assessed using the plaque index and the gingival index prior to surgery and at recall visits at 6 months, 1, 2, 3, 4, and 5 years after initial loading. Bone density and implant/bone fit were evaluated at the time of surgery. Implants were loaded after a healing period of about 2 months. RESULTS: The mean age of the patients at time of enrollment was 60.4 +/- 13.0 years; 44% (86) of the patients were men and 56% (109) were women. In all, 526 implants were placed, 65.4% in the mandible and 34.6% in the maxilla, with 23.0% placed in anterior locations and 77.0% in the posterior. The cumulative success rate of these 526 implants was 97.9% at 5 years. Eight of the 11 implant failures occurred during nonsubmerged healing prior to prosthetic loading. Provisional restorations were placed at 2.1 +/- 0.5 months, at which time implants were evaluated for mobility, gingival health, symptomology, and radiolucency. The distribution of prosthesis types included 118 single-tooth restorations (118 implants), 134 short-span prostheses (327 implants), and 16 long-span restorations (81 implants). DISCUSSION: The benefits of early loading cannot be fully appreciated if there is a substantive increase in implant failures. In this study, a cumulative success rate greater than 97% was maintained throughout 5 years of observation. CONCLUSION: These results suggest that success can be expected with Osseotite implants after a nonsubmerged reduced healing period of 2 months in this patient population.

Five-year survival distributions of short-length (10 mm or less) machined-surfaced and Osseotite implants.

BACKGROUND: In cases of reduced alveolar bone height, implants of short length (10 mm or less) may be employed although there is a perceived risk that because of their small stature they will be unable to tolerate occlusal loads and will fail to osseointegrate. PURPOSE: This report describes an analysis of prospective multicenter clinical studies evaluating the risk for failure of short-length implants, comparing dual acid-etched (DAE) Osseotite implants (Implant Innovations, Inc., Palm Beach Gardens, FL, USA) to machined-surfaced implants. MATERIALS AND METHODS: Admission criteria were the same for both data sets. Baseline variables of demographics including age, gender and smoking status, bone quality, location, implant dimensions, and types of prostheses were compared to ensure balance among groups. Cumulative survival rates (CSRs) were calculated with the Kaplan-Meier estimator. RESULTS: The implant data included 2294 implants for the DAE series and 2597 implants for the machined-surfaced series. Patient demographics showed similar percentages of occurrence for all variables. The distributions of implants between short- and standard-length data sets for baseline variables including width, location, and restorative type were similar, qualifying these data sets for comparison of the independent variable of length. Overall, there was a 2.2% difference in 5-year CSRs between the machined-surfaced short- and the standard-length implants. For these implants a 7.1% difference was observed in the posterior maxilla and an 8.5% difference in the anterior maxilla. For DAE implants the overall difference between "standards" and "shorts" was 0.7%, which is not statistically significant. CONCLUSION: In this analysis the difference in CSRs between short- and standard-length implants was greater for machined-surfaced implants than for DAE implants.

The single-tooth implant: a viable alternative for single-tooth replacement.

BACKGROUND: The use of dental implants for single-tooth replacement cases introduces a challenge to the performance of these restorations. Clinical data suggest that single-tooth implant restorations do not benefit from lateral support from the surrounding dentition as do bridged implants, and that these restorations are subjected to greater masticatory forces. Therefore, single-tooth implants are exposed to an increased risk of failure. This prospective clinical trial was designed to evaluate the cumulative success rate of dual acid-etched single-tooth replacement implants in two clinical centers. METHODS: The study protocol included 59 patients between 19 and 73 years. Implants were evaluated for mobility, infection, and crestal bone loss from 30.9 to 60 months. RESULTS: Seventy-one (71) implants were placed in 59 patients, 20 male and 39 female. Forty-seven (47) were placed in the maxilla and 24 in the mandible. The percentages of anterior and posterior implants were 45.1% and 54.9%, respectively. A total of 13 (18.4%) implants were placed in soft, poor quality (Type IV) bone. Beginning 1 month post-implant placement, cases were followed for 30.9 to 60 months with a mean follow-up of 45.9 months. One implant failed (peri-implant infection) yielding an overall success rate of 98.6%. CONCLUSIONS: This success rate for single-tooth replacement dual acid-etched implants compares favorably with bridged implants and with success rates of other single-tooth implant studies. Dual acid-etched implants performed well even under conditions of poor quality bone, where concomitant bone augmentation was performed, and when used for immediate replacement of extracted teeth.

A multicenter prospective evaluation of 2-months loaded Osseotite implants placed in the posterior jaws: 3-year follow-up results.

In this prospective study, the clinical outcome of 2-months loaded implants placed in the posterior jaws was evaluated after up to 3 years of functional loading. 405 Osseotite implants with microtextured acid-etched surface were consecutively placed in 11 fully and 164 partially edentulous patients (mean age 53.5 +/- 15.3 (S.D.) years) using a one-stage technique. 282 implants, supporting 154 restorations, were placed in the mandible, while 123 implants, supporting 75 restorations, were placed in the maxilla. A total of 99 single-tooth restorations, 119 short-span fixed bridges and 11 full-arch prostheses were applied. The mean time interval from surgery to connection of provisional restoration was 2.0 +/- 0.7 months. 9 failures were reported up to 3 years of follow-up; of these, 4 mandibular and 2 maxillary implants failed during the initial healing period (before prosthesis connection), while 3 mandibular implants failed after loading. No other complications occurred throughout the study. Life table analysis showed a cumulative survival rate of 97.5% for the mandible and 98.4% for the maxilla. Post-loading implant survival rate was 98.9% for the mandible and 100% for the maxilla. The excellent outcome of this interim report suggests that microtextured Osseotite implants in the posterior jaws may safely bear a functional load applied 2 months after insertion. The results of the present study are particularly encouraging for implants placed in the maxilla, since both a significant reduction of the healing period compared to the 6 months suggested by the classical Brånemark protocol, and an excellent post-loading function may be achieved also in low quality bone.