The Role of Different Healing Abutment Sizes in Tissue Volume Preservation of Molar Sockets After Immediate Tooth Extraction and Implant Placement: A Multicenter Clinical Study.

PURPOSE: To evaluate the role of different healing abutment designs in compensating for the buccolingual volumetric tissue change that occurs following flapless single-tooth immediate extraction placement in the molar area. MATERIALS AND METHODS: Patients in need of extraction and replacement of a first or second molar in the mandible or maxilla were consecutively recruited. Immediately after extraction and implant placement, an abutment was connected. Five different types of abutments were randomly selected to be used for each case. The study population was divided into five categories according to abutment design: 5-mm diameter healing abutment (group 1); 6-mm diameter healing abutment (group 2); 7.5-mm diameter healing abutment (group 3); provisional restoration (group 4); and customized healing abutment (group 5). The buccopalatal dimension (BPD) was measured on the study casts at 1, 3, and 5 mm apical to the free gingival margin, and horizontal volumetric changes were compared between baseline and 2, 4, and 6 months. RESULTS: A total of 267 implants were inserted in 246 patients. The breakdown of placed implants for each group was as follows: 67 implants in group 1; 64 in group 2; 71 in group 3; 33 in group 4; and 32 in group 5. Changes in the mean horizontal ridge dimension were as follows. After 6 months in group 1, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 4.21 ± 0.158, 3.38 ± 0. 178 and 2.35 ± 0.178 mm. In group 2, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 3.16 ± 0.198, 2.56 ± 0.198, and 1.62 ± 0.198 mm. In group 3, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 2.53 ± 0.138, 2.16 ± 0.144, and 1.56 ± 0.144 mm. In group 4, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 1.11 ± 0.179, 1.23 ± 0.179, and 1.12 ± 0.179 mm. In group 5, BPD diminished at 1-, 3-, and 5-mm distance from the free gingival margin, respectively, by 0.25 ± 0.225, 0.30 ± 0.225, and 0.19 ± 0.225 mm. Mixed-effect regression and post hoc means comparisons were used to model the impact of the restoration technique, height of measurement, and time on BPD using a significance reference level of .05. Statistical analysis showed that the type of abutment, the height of measurement, and the time significantly influenced the BPD and that there were complex interaction effects between these variables. CONCLUSION: The observed volumetric soft tissue changes in the 6-month short-term follow-up appeared to vary based on the use of different healing abutment sizes that were connected to implants placed immediately after tooth extraction in the molar area. In particular, the use of a customized healing abutment resulted in preservation of the original horizontal dimension of the molar soft tissue.

Implants Survival Rate in Regenerated Sites with Innovative Graft Biomaterials: 1 Year Follow-Up.

In thirteen different dental clinics in Singapore, Spain, Czech Republic and Italy, 504 patients were selected, and 483 dental implants were placed in maxillary sites after alveolar socket preservation (ASP) procedures with an autologous demineralized tooth extracted as graft material from an innovative Tooth Transformer device was obtained. All procedures used were reported in n°638 Ethical Committee surgical protocol of University of Chieti and approved. After 4 months, at dental implant placing, bone biopsies were performed to evaluate the histologic outcomes, and 12 months after implant loading, global implant survival rate, failure percentage and peri-implant bone loss were detected. After ASP, only 27 post-operative complications were observed and after 4 months, bone biopsy histomorphometric analysis showed a high percentage of bone volume (BV) 43.58 (±12.09), and vital new bone (NB) 32.38 (±17.15) with an absence of inflammation or necrosis areas. Twelve months after loading, only 10 dental implants failed (2.3%), with a 98.2% overall implant survival rate, nine cases showed mucositis (1.8%) and eight showed peri-implantitis (1.6%). At mesial sites, 0.43 mm (±0.83) of bone loss around the implants was detected and 0.23 mm (±0.38) at the distal sites with an average value of 0.37 mm (±0.68) (p > 0.568). Several studies with a longer follow-up will be necessary to confirm the preliminary data observed. However, clinical results seem to suggest that the post-extraction socket preservation procedure using innovative demineralized autologous tooth-derived biomaterial may be a predictable procedure to produce new vital bone able to support dental implant rehabilitation of maxilla edentulous sites.

Alveolar Socket Preservation with Different Autologous Graft Materials: Preliminary Results of a Multicenter Pilot Study in Human.

BACKGROUND: The histological and histomorphometrical results were evaluated between vital whole and non-vital endodontically treated teeth used as autologous grafts in post-extractive socket preservation procedures. METHODS: Twenty-eight patients (average age 51.79 ± 5.97 years) with post-extractive defects were enrolled in five dentistry centers. All patients were divided into two groups: with whole teeth (Group 1) and teeth with endodontical root canal therapy (Group 2). The extracted teeth were processed with the Tooth Transformer device to obtain a demineralized and granulated graft material used with a resorbable collagen membrane for socket preservation. After four months, 32 bone biopsies were obtained for histological, histomorphometric, and statistical analysis. RESULTS: During the bone healing period, no infection signs were observed. Nineteen biopsies in group 1 and 13 biopsies in group 2 were detected. The histological analysis showed neither inflammatory nor infective reaction in both groups. Autologous grafts surrounded by new bone were observed in all samples and, at high magnification, partially resorbed dentin and enamel structures were detected. No gutta-percha or cement was identified. Small non-statistically significant differences between the groups, in total bone volume (BV), autologous graft residual, and vital bone percentage were detected. CONCLUSIONS: The study showed that the TT Transformer grafts were capable of producing new vital bone in socket preservation procedures. The histomorphometric results showed no statistical differences comparing whole and endodontically treated teeth in bone regeneration. Further studies will be carried out in order to understand the advantages of the autologous graft materials obtained from the tooth compared with the current biomaterials in bone regeneration treatments.

The monocortical window (MCW): a modified split-crest technique adopting ligature osteosynthesis.

Split-crest procedures performed with ultrasonic devices have proven to be a viable and effective surgical treatment when the alveolar ridge shows forms of resorption in thickness while its height remains virtually unchanged. However, in the case of stiff, type 1, corticalized mandibular bone, it may be very difficult or even impossible to have any elasticity and lateral augmentation in between the split bone walls. Furthermore, a complete detachment of the outer lamellae may also occur during expansion maneuvers or during implant insertion. This study describes the use of a steel-wire ligature osteosynthesis technique to give primary stability both to the expanded cortical window and to the implants themselves when they have none at all. This osteosynthesis is simple, quick, safe, and bone-saving in force delivery. It is also extremely cheap as well as being effective in obtaining ridge expansion, bone regeneration, and implant positioning in an all-in-one procedure. This article describes the foundations in the literature as well as new elements in the technique. Three short case studies are used by way of example.