Three-year prospective multicenter study evaluating marginal bone levels and soft tissue health around a one-piece implant system.

PURPOSE: The aim of this clinical investigation was to evaluate marginal bone remodeling and soft tissue health surrounding a novel one-piece implant system over a 3-year study period. MATERIALS AND METHODS: Subjects missing at least one tooth in either arch were consecutively enrolled in this open prospective 3-year investigation. Five clinics were invited to participate. Strict inclusion and exclusion criteria were used. Marginal bone levels were evaluated using radiographs taken at implant insertion, 6 months, and annually thereafter. Plaque and bleeding indices were recorded at 3 and 6 months and 1 and 3 years following implant insertion. The shapes of papillae were evaluated at implant insertion with the provisional restoration in place, at the insertion of the definitive restoration, and at the 3-year follow-up, using Jemt's papilla index. Life tables and the Mann-Whitney U test were used for statistical analyses. RESULTS: Fifty-six patients were restored with a total of 82 one-piece implants; 47 patients attended the 3-year appointment. One implant had to be removed 1 month postinsertion, giving a cumulative survival rate of 98.8% for the 3-year study period. Most bone resorption (mean, 1.19 ± 1.38 mm; n = 61) occurred during the first year of function, while there was minimal change in mean marginal bone levels between 1 and 3 years (-0.07 ± 1.07 mm; n = 58). Normal peri-implant mucosa was registered for more than 81% of the sites, and no visible plaque was registered for more than 54% of the sites. CONCLUSION: This prospective 3-year multicenter study showed stable marginal bone levels, good soft tissue health, and a high implant survival rate, supporting the hypothesis that the presented one-piece implant system has the capacity to maintain both hard and soft tissues after the first year of initial bone remodeling.

Clinical evaluation of the zygoma implant: 3-year follow-up at 16 clinics.

PURPOSE: The purpose of this clinical investigation was to evaluate the treatment outcome with zygoma implants with regard to implant survival, patient satisfaction, and function of prosthesis replacement after 3 years. PATIENTS AND METHODS: The treatment outcome of 76 patients treated with 145 zygoma fixtures at 16 centers was evaluated with regard to implant survival. Status of peri-implant mucosa and amount of plaque were registered annually. Patients' and dentists' evaluations of the functional and esthetic outcome of the treatment were assessed at delivery of prosthesis and thereafter at each follow-up visit. RESULTS: Sixty of 76 patients were followed for 3 years after prosthetic delivery. Five of 145 placed zygoma implants failed during the course of the study resulting in an overall implant survival rate of 96.3%. At the 3-year follow-up, 75% of the implants sites were registered with normal peri-implant mucosa and 68% with no visible plaque. The patients were fully satisfied with the esthetic and functional outcome of the treatment in 86% and 71%, respectively, at the 3-year follow-up visit. All reported data from dentists scored from acceptable to excellent. CONCLUSION: The multicenter study showed a high predictability of the zygoma implant-supported rehabilitation.

Clinical evaluation of a prospective multicenter study on 1-piece implants. part 1: marginal bone level evaluation after 1 year of follow-up.

PURPOSE: The aim of the present investigation was to evaluate the marginal bone level after 1 year of follow-up of 1-piece implants after immediate provisional restoration fabrication. MATERIALS AND METHODS: Patients received NobelDirect and NobelPerfect 1-piece implants (Nobel Biocare, G6teborg, Sweden) that were immediately restored and placed into function as part of a 3-year, multicenter investigation. Life table analysis was used for evaluation of implant cumulative survival rates. The Student t test (for dichotomous variables) and Pearson correlation (for continuous and ordered categorical variables) were used to estimate the influence of separate parameters on marginal bone. RESULTS: Eighty-seven patients received 152 NobelDirect or NobelPerfect 1-piece implants. Of these, 81 patients returned for the 1-year follow-up and 21 for the 2-year follow-up. Three implants were lost, resulting in a cumulative survival rate of 97.9% after up to 2 years. The average marginal bone level at implant placement was 0.33 mm (SD 1.20, n = 141) superior to the reference point (lower edge of the implant collar). Marginal bone level was -0.77 mm (SD 1.33, n = 138) at 6 months and -0.98 mm (SD 1.38, n = 123) at 1 year. Average bone level at the 2-year follow-up was 0.17 mm (SD 1.20, n = 26). After 1 year of loading, bone level in the maxilla was more apical compared to that in the mandible (P = .05), and a positive correlation was found between bone level at placement and bone level at 12 months (P = .008). Shallow implant positioning resulted in less marginal bone remodeling compared to deep implant positioning. CONCLUSION: On the basis of this prospective multicenter study, stable marginal bone level and soft tissue support the hypothesis that the 1-piece implant has the capacity to preserve both hard and soft tissue.

Prospective multicenter study of marginal bone level and soft tissue health of a one-piece implant after two years.

STATEMENT OF PROBLEM: A novel 1-piece implant purported to provide for stable tissue support, immediate function, and immediate placement in extraction sockets has been developed. Stabilization of the marginal bone level over time requires documentation. PURPOSE: The aim of this study was to evaluate marginal bone level differences and soft tissue health between the 1- and 2-year follow-up of a 1-piece implant design. MATERIAL AND METHODS: Eighty-two implants, restoring both single teeth and multiple edentulous situations, in 56 consecutively treated patients, were included. Marginal bone level was evaluated on radiographs made at implant insertion, 6-month follow-up, and annually thereafter. At 3-, 6-month, and 1-year follow-ups, presence of plaque and the soft tissue response were evaluated using plaque and bleeding on probing indexes. The papilla index was used to determine papilla size at implant insertion with the provisional restoration in place and at the insertion of the definitive restoration. The change over time in marginal bone level was analyzed with a 1-way analysis of variance (ANOVA) paired design with time as main effect (1 to 2 years) and subjects as block effect (alpha=.05). RESULTS: One implant failure occurred, resulting in a 98.8% cumulative survival rate (CSR) for the follow-up time of 2 years. The mean (SD) change in bone level between years 1 and 2 was 0.08 mm (1.19) (95% CI-0.30 to 0.46) (P=.68), demonstrating a stable marginal bone level. Normal implant mucosa was noted for approximately 90% of the sites at the 1-year follow-up. The mean (SD) papilla score at placement was 1.3 (0.66) and increased to 1.7 (0.67) at insertion of the definitive prosthesis. CONCLUSIONS: The stable marginal bone level and soft tissue health observed indicate that the 1-piece implant tested has the ability to preserve both hard and soft tissue. Based on the high implant survival rate and favorable tissue response, the 1-piece implant can be recommended for clinical use.

Feasibility and long-term stability of surgically assisted rapid maxillary expansion with lateral osteotomy.

Surgically assisted rapid maxillary expansion (SARME) has become a widely used and acceptable means to expand the maxilla in adolescents and adult patients. The method takes advantage of bone formation at the maxillary edges of the midline, while they are separated by an external force. The purpose of the present retrospective investigation was to evaluate the feasibility and long-term stability of maxillary expansion in patients in whom lateral pre-expansion osteotomy had been performed. The subjects were 20 patients (14 females, six males, mean age 30.6 years, range 16.2-44.2 years) whose malocclusions were treated solely or partly with SARME during 1988-1996. Two orthodontists carried out the post-orthodontic expansion treatment. The surgical technique followed a minimally invasive osteotomy on the lateral maxillary walls. Study models were obtained before surgery (T1), once expansion and the following orthodontic treatment were completed, before possible second-stage osteotomy (T2), and at long-term follow-up (T3). Using the study models, the width of the dental arch was measured with a digital sliding calliper. In addition, transverse occlusal relationships were examined at each time point. The results indicated that (1) SARME is possible when the minimally invasive operation technique is used, (2) long-term stability of maxillary expansion following the present technique compares favourably with the widening and stability achieved with other, more invasive, osteotomies. With age, several possible uncertainties are introduced to affect the course of SARME adversely. Therefore, more extensive osteotomies can be recommended in older patients.

A clinical evaluation of the Zygoma fixture: one year of follow-up at 16 clinics.

PURPOSE: To evaluate treatment outcome with Zygoma fixtures (Nobel Biocare, Göteborg, Sweden) with regard to fixture survival, patient satisfaction, and function of prosthesis replacement. MATERIALS AND METHODS: The treatment outcome of 76 patients treated with 145 Zygoma fixtures at 16 centers was evaluated. Patient's and dentist's evaluations of the functional and aesthetic outcome of the treatment were assessed at delivery of prosthesis and at the 1-year follow-up visit. At the 1-year follow-up visit, the status of the peri-implant mucosa around the abutments and the amount of plaque were registered. RESULTS: Sixty-six of the 76 patients, with 124 Zygoma fixtures supporting the prosthetic restorations, were evaluated at the 1-year follow-up. The overall survival rate for the Zygoma fixtures was 97.9% after 1-year of follow-up. Eighty percent of the patients were fully satisfied with both aesthetic and functional outcome at the time of prosthetic insertion and at the 1-year follow-up. All reported data from the dentists, with the exception of one restoration with several abutment screw loosenings, scored from acceptable to excellent for the aesthetic and functional outcome of the treatment. The status of peri-implant mucosa was recorded as normal in approximately 60% of the sites. Plaque, when present, was more often detected on the palatal surfaces compared with the buccal surfaces. CONCLUSION: This 1-year follow-up of Zygoma fixtures has shown good results with an acceptable number of minor complications and a majority of satisfied patients.