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Notes: Today, partially edentulous patients represent the majority of patients seeking treatment with implant-supported prostheses. This chapter presents the specific aspects of the surgical handling of partially edentulous patients with either single-tooth gaps, extended edentulous spaces or distal extension situations. Due to differences in treatment objectives, a distinction is made between sites without esthetic priority (non-esthetic sites) and with esthetic priority (esthetic sites). In non-esthetic sites, the primary goal of the surgical therapy is to achieve a predictable hard and soft tissue integration of the implant to re-establish function with the implant-supported prosthesis. In esthetic sites, the goal of surgical therapy is to achieve successful tissue integration and to obtain esthetic soft tissue contours to re-establish both function and esthetics. Therefore, the surgeon must have a clear understanding of the specific needs in a given situation, and must master the necessary surgical techniques concerning a correct implant placement and a correct soft tissue handling to achieve the treatment objectives. In non-esthetic sites, a non-submerged approach is clearly preferred, thus avoiding a second-stage procedure for abutment connection. If a soft tissue correction is necessary to re-establish keratinized peri-implant mucosa, this is done at the time of implant placement with mucogingival surgery. In esthetic sites, a submerged implant placement is preferred to achieve esthetically pleasing soft tissue contours. If a soft tissue augmentation is necessary, this is done at the time of implant placement with connective tissue grafts. Thus, the second surgical procedure after 8–10 weeks of healing is reduced to a mucosaplasty like a punch biopsy, avoiding an open flap procedure. Based on favorable properties of the TPS surface, short implants (6 or 8 mm) and short healing periods of 3–4 months have been successfully utilized in partially edentulous patients in the last 14 years. The introduction of the SLA surface allows a further reduction of the healing period to 6 weeks of healing in all sites with normal bone density (class I–III). In summary, the ITI philosophy offers straightforward surgical concepts to predictably achieve the treatment objectives with the least demanding surgical protocol, reducing the related chairtime and costs for the patient and the clinician.

Notes: In recent years, bone grafts and bone substitutes have been increasingly utilized underneath barrier membranes to optimize the treatment outcome of bone reconstructive therapy for defects in the alveolar process. In the present study, 4 different filling materials were evaluated in bone defects of similar dimensions in the mandible of miniature pigs. Blood clots and autografts were used as controls. The defects were covered with barrier membranes and allowed to heal for 4, 12 or 24 weeks. Histologic examination demonstrated that bone repair progressed through a programmed sequence of maturation steps closely resembling the pattern of bone development and growth regardless of whether bone grafts or substitutes were present or not. Histomorphometric analysis showed that autologous bone grafts (autografts) had the best osteoconductive properties during the initial healing period, with 39% of newly formed bone inside the membrane-covered defects at 4 weeks of healing. In addition, 87% of the graft surfaces were already covered by bone at this time. Both values were significantly higher for autografts than for the 4 alternative bone fillers (P〈0.05). At 12 weeks, these differences were no longer apparent, with all 5 filling materials showing similar values. Among the tested bone substitutes, tricalcium hosphate (TCP) showed a significantly higher percentage of bone fill at 24 weeks of healing. It can be concluded that sites filled with autografts clearly demonstrated the best results underneath barrier membranes in the early phase of healing. As far as degradation and substitution are cnncemed, TCP showed the most promising results. This filler, however, needs to be tested further in a more demanding animal model. Less favorable results were obtained for coral-derived hydroxyapatite granules and for demineralized freeze-dried bone allografts.

Notes: In both normal and membrane-assisted situations, healing events are modulated by the activity of endogenous protein molecules known as cytokines. Due to its mitogenic and chemotactic characteristics, the addition of rhTGF-β1 should increase the rate of osteogenesis or increase the potential for bone regeneration in oral osseous defects. This study evaluates the effects of an osteoconductive biodegradable matrix incorporating human recombinant transforming growth factor beta 1 (rhTGF-β1) in conjunction with barrier membranes on bone regeneration in canine alveolar ridge defects. A matrix of calcium carbonate and hydroxyethyl starch served as the carrier for test concentrations of 2.0 μg/0.8 ml and 20.0 μg/0.8 ml of rhTGF-β1. One surgically prepared site in each of 13 adult male foxhounds received 1 of 4 experimental treatment regimens, with 6 sites utilizing barrier membranes. Four sites in each of 2 additional animals, two containing carrier matrix only and 2 with the additional barrier membrane, served as controls. Specimens were retrieved after 2 months of healing and processed for routine light microscopy. The quantity and composition of regenerated bone was examined. Analysis of variance revealed a statistically significant increase (P〈0.05) in the development of bone with the use of rhTGF-β1. Likewise, a statistically significant increase in regeneration was found in membrane-protected sites over non-membrane-protected sites. No statistically significant difference was noted between the low and high dose treatments. The authors conclude that the use of rhTGF-β1 in conjunction with a barrier membrane greatly enhances bone regeneration in osseous oral defects.

Notes: In the present multi-center study. non-submerged ITI implants were prospectively followed to evaluate their long-term prognosis in fully and partially edentulous patients. In a total of 1003 patients, 2359 implants were consecutively inserted. Following a healing period of 3–6 months, the successfully integrated implants were restored with 393 removable and 758 fixed restorations. Subsequently, all consecutive implants were documented annually up to 8 years. At each examination, the clinical status of all implants was evaluated according to predefined criteria of success. Therefore, the data base allowed the evaluation of 8-year cumulative survival and success rates for 2359 implants. In addition, cumulative success rates were calculated for implant subgroups divided per implant type, implant length. and implant location. Furthermore, the actual 5-year survival and success rates could be determined for 488 implants. During the healing period, 13 implants did not successfully integrate, whereas 2346 implants fulfilled the predefined criteria of success. This corresponds with an early failure rate of 0.55%. During follow-up, 19 implants were classified as failures due to several reasons. In addition, 17 implants (= 0.8%) demonstrated at the last annual examination a suppurative periimplant infection. Including 127 drop out implants (= 5.4% drop out rate) into the calculation, the 8-year cumulative survival and success rates resulted in 96.7% and 93.3%, respectively. The analysis of implant subgroups showed slightly more favorable cumulative success rates for screw type implants (〉 95%) compared to hollow-cylinder implants (91.3%). and clearly better success rates for mandibular implants (= 95%) when compared to maxillary implants (= 87%). The actual 5-year survival and success rates of 488 implants with 98.2% and 97.3%. respectively, were slightly better than the estimated 5-year cumulative survival and success rates of 2359 implants indicating that the applied life table analysis is a reliable statistical method to evaluate the long-term prognosis of dental implants. It can be concluded that non-submerged ITI implants maintain success rates well above 90% in different clinical centers for observation periods up to 8 years.

Notes: Abstract Aim: This study evaluated the impact of the IL-1 genotype and smoking status on the prognosis and development of complications of osseointegrated implants.Material and methods: The clinical charts of 180 consecutively admitted patients were analyzed with respect to the occurrence of biological complications in conjunction with oral implants. Biologic complications were defined as clinical conditions with suppuration from the peri-implant sulcus, development of a fistula or peri-implantitis with radiologic bone loss. All patients had received one or more ITI® dental implants, which had been in function for at least 8 (range: 8–15) years. This patient population had received 292 implants. From these, 51 implants in 34 patients showed late (infectious) biologic complications, and 241 implants had survived without any biologic complications at all.Results: Of the 180 patients, 53 were smokers, who were subdivided in a series of classes according to their intensity of smoking and 127 were never smokers. Sixty-four of 180 (36%) patients tested positive for the IL-1 genotype polymorphism. This prevalence corresponds to previous reports for the prevalence of European descent populations. The results for the non-smoking group indicated no significant correlation between implant complications and a positive IL-1 genotype. However, there was a clear association for heavy smokers between a positive IL-1 genotype and implant complications. 6 of 12 or half of the heavy smokers and IL-1 genotype-positive patients had either an implant failure, i.e. loss of implant, or a biologic complication during the follow-up period.Conclusions: These findings have led to the conclusion that there is a synergistic effect between a positive IL-1 genotype and smoking that puts dental implants at a significantly higher risk of developing biologic complications during function.

Notes: Objective: To investigate whether cross-section imaging influences the planning and therapy of standard implant cases in the posterior mandible.Material and methods: In a prospective study conducted over 16 months, the planned treatment (standard implant therapy without bone augmentation procedures in the premolar and molar regions of the mandible) was compared with the postoperative result in 50 randomly selected patients. Clinical examinations and panoramic radiographs were performed pre- and postoperatively, whereas cross-sectional tomography was performed only preoperatively.Results: The vertical magnification factor in the panoramic radiographs was very constant pre- and postoperatively with 1 : 1.27 and in the spiral tomograms with 1 : 1.52. In 11 of 77 implant sites, the mandibular canal could not be evaluated in the spiral tomograms. The additional information from cross-sectional spiral tomography did not influence the original planning in 74 of 77 (96.1%) implant sites. Based on the postoperative panoramic radiograph, the average distance from the tip of the implants to the mandibular canal was 3.04±2.06 mm. In two cases (2.6%), transient postoperative altered tactile sensation of the mental nerve was found.Conclusion: The information from preoperative cross-sectional spiral tomography has minor impact on treatment planning in standard implant cases in mandibular premolar and molar regions. The clinical examination provides sufficient information for selecting implant diameter and the panoramic radiograph provides sufficient information for implant length selection.