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The present study aimed to evaluate the osseoconduction ability of an airborne particle-abraded and etched (SAE) titanium alloy surface when placed in humans with poor bone quality. Four patients scheduled to receive an implant-supported full-arch prosthesis received two additional reduced-diameter implants to be harvested after 6 months of submerged healing. Undecalcified vestibulopalatal/vestibulolingual histologic sections were prepared after the micro-computerized tomography (μCT) examination. Six implant sides from four biopsied implants displayed a type IV bone environment and were included in the present study. Bone-to-implant contact (BIC) was first measured on each implant side. The estimated initial BIC (E-iBIC) was evaluated by superimposing the implant profile 0.25 mm away from its actual position. The μCT provided information about the local and adjacent bony architecture. The mean BIC was 62.5% ± 10.6%, while the mean E-iBIC was 33.1% ± 4.4%. The E-iBIC/BIC ratio was 1.81 ± 0.38. The 3D μCT sections showed the thin bone trabeculae covering the implant surface; although they seemed to be separated from the rest of the bony scaffold, they were much more interconnected than what appeared to be on the 2D histologic preparations. This limited number of human histologic samples document, for the first time, that the SAE titanium alloy implant surface is apparently osseoconductive when placed in poor human bone quality. The average BIC was 1.81 times higher than the E-iBIC. This high osseoconductivity may explain the predictable clinical behavior of implants with this type of SAE textured surface in type IV bone.

The aim of this report is to present a technique for buccal soft tissue contour augmentation with the use of a porcine volume-stable collagen matrix (VSCM). Augmentation of buccal soft tissue at the time of implant placement is often a necessity but is mostly performed using autogenous tissue. The technique using a VSCM can be done at the time of implant placement or, in the case of a two-stage procedure, at the time of implant uncovering. Here, clinical outcomes are reported in two cases when using VSCM concurrently with implant placement at sites in need of buccal contour augmentation to achieve a functional, esthetic result. The use of a xenograft poses several advantages over autogenous tissue while providing similar gains in soft tissue thickness. By eliminating the need to harvest a soft tissue graft from the palate, patient morbidity is reduced, and the reliance on palatal tissue thickness, to determine the amount of achievable augmentation, is eliminated.

Certain bone morphologies and soft tissue thickness (ie, phenotype) are considered to be risk factors for the development of gingival recessions following orthodontic tooth movement. Preoperative evaluation of the periodontal phenotype, in the frame of orthodontic treatment plan, identify teeth at high risk for mucogingival complications related to orthodontic therapy. The new surgical technique is illustrated in a clinical case. A patient with a thin phenotype without visible gingival recession had bone dehiscences in the anterior mandible. Prior to orthodontic treatment, simultaneous bone and soft tissue augmentation was performed using the combination of a highly cross-linked ribose porcine type I collagen membrane and a subepithelial palatal connective tissue graft. Two years after augmentation surgery and initiation of orthodontic treatment, a thick buccal tissue with a wide band of attached gingiva was observed without any clinical signs of root prominences, indicating a substantial change in periodontal phenotype. The clinical findings were corroborated by the 3D analysis, demonstrating substantial bone apposition on the buccal aspect of all roots in the treated area. The described surgical technique offers a valuable approach for regenerating hard and soft tissues in deficient areas prior to orthodontic therapy, thus preventing the development of gingival recessions.

Buccal bone remodeling around immediate implants placed in animals with streptozotocin (STZ)-induced diabetes has not been investigated. The present histologic and microcomputed tomography (μCT) in vivo experiment assessed the buccal bone remodeling around immediate implants, extraction socket healing, and bone-to-implant contact (BIC) in dogs with and without STZ-induced diabetes. Three male beagle dogs with STZ-induced diabetes and three healthy dogs (controls) were included. Fasting blood glucose levels were measured using a glucometer. Under general anesthesia, all animals underwent atraumatic tooth extraction of bilateral maxillary and mandibular second premolar teeth using Piezosurgery and immediate implant placement in the distal root socket. Primary closure was achieved for all implants and adjacent socket sites. After 11 months, all animals were sacrificed, and buccal bone thickness (BBT), marginal bone loss (MBL), BIC, and mesial extraction socket bone volume were assessed in control and diabetic animals using histologic and μCT examination. High-resolution μCT analyses were performed to identify the percentage of osteocytes and blood vessels in bone specimens harvested from a mesial extraction socket in each group. BBT and BIC were significantly higher in control dogs (P < .05), and diabetic dogs demonstrated significantly more MBL than control dogs (P < .05). Compared to healthy subjects, the sockets of induced diabetic dogs lost over 50% of bone horizontally and vertically. Control group had more significant osteocytes (38.85%) and blood vessels (37.87%), whereas the same values for STZ-induced diabetic dogs were 27.92% and 27.76%, respectively. Buccal bone loss and MBL were significantly higher around immediate implants placed in dogs with STZ-induced diabetes and were associated with multiple implant buccal thread exposure. A large percentage of socket space in diabetic dogs healed with nonosseous structure following tooth extraction.

This study involves a group of 168 teeth in 126 patients treated with crown lengthening and tooth reconstruction (experimental group), and a group of 75 teeth from 62 patients that were judged irrational to treat, extracted, and replaced (control group). In the control group, 13 teeth in 12 patients were not replaced; 37 were replaced with an implant-supported crown, 14 with a tooth-supported partial denture, 2 with a Maryland partial denture; and 9 patients requested a removable prosthesis. In the experimental group, 44 teeth in 37 patients received a conservative restoration (24 direct and 20 indirect), while 124 teeth in 94 patients received a full crown. All 168 teeth were surgically treated with minimally invasive crown lengthening. Endodontic treatment and orthodontic extrusion were applied when necessary. Treatment resulted in healthy periodontal and dental/implant conditions at the 1-year follow-up in both groups. Function and esthetics were described from satisfactory to extremely satisfactory by patients of both groups, with the exception of three patients in the control group who received a mobile prosthesis restoration and reported some difficulties in chewing. When comparing treatment cost and duration of the reconstructed teeth (experimental group) to the treatment cost and duration of extracted and replaced teeth (control group), the difference is significantly in favor of the preservation of natural teeth, both monetarily and in terms treatment time. Saving a tooth with a compromised crown is more favorable for the patient than extraction and replacement. This conservative approach is advisable to clinicians whenever the clinical conditions enable treatment.

A novel macro-hybrid implant design was introduced to afford high apical primary stability and more coronal space to preserve the circumferential extraction socket architecture. This study presents 1-year data from a prospective single-arm cohort study. The data was distilled based on the following criteria: (1) single-tooth immediate tooth replacement therapy (ITRT) in the maxillary anterior and premolar regions in intact (Type 1) extraction sockets that were (2) treated with the dual-zone grafting technique. The clinical and radiographic outcomes of 48 ITRT implants were evaluated. The mean ± SD labial plate dimension changes were 0.33 ± 0.41 mm at the implant abutment interface (L1) and 0.34 ± 0.40 mm at 5.0 mm below (L2). The mean labial plate dimension (thickness) at the 1-year recall was 2.27 ± 0.88 mm (L1) and 1.95 ± 0.95 mm (L2). At ITRT, the ridge contour at the free gingival margin and 3.0 mm below it were 7.54 ± 0.93 mm and 9.44 ± 2.36 mm, respectively; after final restoration delivery, the corresponding values were 7.45 ± 0.95 mm and 10.23 ± 2.30 mm, respectively. The peri-implant soft tissue thickness (PISTT) at the time of implant-level impression-making was 3.29 ± 0.73 mm, with an average Pink Esthetic Score of 12.79. A macro-hybrid implant design showed high levels of primary stability (~60 Ncm), stable ridge contour at 1 year, a labial plate dimension between 1.5 and 2.0 mm, and PISTT > 3.0 mm, which may be a critical factor in providing stable, long-term esthetic outcomes.

Achieving primary stability is a critical challenge presented by immediate implant therapy. Surgeons often utilize wider, tapered implants for this purpose, or they use longer implants to achieve primary stability. Both strategies are associated with negative ramifications. Prosthetically guided implant placement must respect biologic principles, such as tooth-implant and implant-implant distance, gap space between the implant and the facial cortex, and, when possible, screw-retention of the prosthesis. A novel implant design geared toward achieving a predictable level of primary stability while adhering to the aforementioned physiologic principles was recently introduced. Both primary and secondary implant stability, along with hard and soft tissue stability, are demonstrated in this study of 107 consecutively placed implants. Rotational and axial stability can be produced with this newly designed implant, along with predictable osseointegration and tissue preservation.

A postextraction socket is always open to different treatment possibilities. A straightforward clinical classification may help evaluate which surgical approach is best suited for the case being treated. Four different classes are defined on the basis of the local anatomy of the site, available bone volume, and soft tissue level. For every clinical situation, either immediate placement, early placement, alveolar ridge preservation, or staged approach can be selected as a treatment modality according to the classifications listed.