Bücher und Digitale Medien

This investigation was designed to evaluate clinical feasibility of the use of narrow-diameter implants to support mandibular overdenture. Twelve patients presenting with an edentulous mandible were recruited from 9 dental offices (n=1~2 per office). Each patient received two to four implants in the mandible. The implants were placed without additional bone augmentation. 36 implants were placed in total. All achieved satisfactory crestal bone stability and soft tissue maintenance at 1 year post final prosthetic restoration.

A 12-month prospective consecutive case series study was conducted to evaluate the effectiveness of a novel porcine collagen matrix to correct moderate to severe buccogingival recession defects. A total of 10 healthy patients (8 women and 2 men; age range: 30 to 68 years) with 26 maxillary and mandibular recession gingival defects > 4 mm deep were included. Healthy maturation of gingival tissues with natural color and texture matching the adjacent soft tissue areas were observed at all reevaluation visits. Complete root coverage was not achieved in all cases, possibly due to severe buccal bone loss in most of the selected cases, which negatively impacted the results. Nevertheless, when a novel porcine collagen matrix was used, a mean root coverage of 63.15% was achieved, and gains in clinical attachment level and keratinized tissue height were seen. Future randomized clinical trials are needed to further explore the potential of porcine collagen matrix for treatment of localized gingival recession defects.

This investigation was designed to evaluate crestal bone stability and soft tissue maintenance to Laser-Lok tapered tissue-level implants. Twelve patients presenting with an edentulous site adequate for the placement of two implants were recruited from four dental offices (2 to 4 patients per office). Each patient received two Laser-Lok tissue-level implants placed with a 3-mm interimplant distance according to a surgical stent. The implants were placed so that the Laser-Lok zone sat at the junction between hard and soft tissues. A total of 24 implants were placed, and all achieved satisfactory crestal bone stability and soft tissue maintenance 1 year after receiving the final prosthetic restoration.

Making treatment decisions in dental implantology has evolved over the last five decades. These decisions and the clinical management of sites thereafter are selected based on recent changes, including the achievement of osseointegration, reestablishment of biologic width bone remodeling, the peri-implant soft tissue phenotype, the way peri-implantitis is defined, and advancements in digital technology. This article discusses these key aspects and their effects and influence on implant therapy.

This ex vivo study evaluates the incidence of sinus membrane perforation during implant site osteotomy with two different types of drills and drilling techniques. Fifty goat heads with 50 sinus pairs (100 sinus sides) were assigned to two groups (osseodensification bur [OB] group and inverse conical shape bur [ICSB] group) to simulate transcrestal sinus elevation (50 sinus sides per group). An osteotomy was performed to pass through the lateral sinus wall no more than 3 mm. The integrity of the sinus membranes was examined and confirmed under a microscope. Of the 50 sinuses per group, the OB group presented with 14 (28%) perforated sinuses, while the ICSB group presented with 2 (4%) perforated sinuses. Of the 14 perforations from the OB group, 6 (42.9%) showed a pinpoint perforation pattern, 4 (28.5%) of which were not visible until direct air pressure was applied. Overall, the ICSB drill group demonstrated a lower sinus perforation rate than the OB group.

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.