Impact of simultaneous placement of implant and block bone graft substitute: an in vivo peri-implant defect model

Abstract

Background Insufficient bone volume around an implant is a common obstacle when dental implant treatment is considered. Limited vertical or horizontal bone dimensions may lead to exposed implant threads following placement or a gap between the bone and implant. This is often addressed by bone augmentation procedures prior to or at the time of implant placement. This study evaluated bone healing when a synthetic TiO2 block scaffold was placed in circumferential peri-implant defects with buccal fenestrations. Methods The mandibular premolars were extracted and the alveolar bone left to heal for 4 weeks prior to implant placement in six minipigs. Two cylindrical defects were created in each hemi-mandible and were subsequent to implant placement allocated to treatment with either TiO2 scaffold or sham in a split mouth design. After 12 weeks of healing time, the samples were harvested. Microcomputed tomography (MicroCT) was used to investigate defect fill and integrity of the block scaffold. Distances from implant to bone in vertical and horizontal directions, percentage of bone to implant contact and defect fill were analysed by histology. Results MicroCT analysis demonstrated no differences between the groups for defect fill. Three of twelve scaffolds were partly fractured. At the buccal sites, histomorphometric analysis demonstrated higher bone fraction, higher percentage bone to implant contact and shorter distance from implant top to bone 0.5 mm lateral to implant surface in sham group as compared to the TiO2 group. Conclusions This study demonstrated less bone formation with the use of TiO2 scaffold block in combination with implant placement in cylindrical defects with buccal bone fenestrations, as compared to sham sites.

Osteoblasts in a Perfusion Flow Bioreactor—Tissue Engineered Constructs of TiO2 Scaffolds and Cells for Improved Clinical Performance

“…The BTE approach using in vitro expansion of cells on a scaffold prior to grafting into bone represents a promising alternative to current clinical treatments. TiO2 scaffolds, as used here, show promising results in various in vivo experiments [6,8,11]. However, in a recent study [12] using a chronic non-contained bone defects application, less bone formation was observed in the TiO2 groups compared to membrane alone at the final time point of 12 weeks of healing.…”

“…Although TiO 2 scaffolds favor new bone ingrowth in vivo [6,8,11], in chronic bone defects the rate of bone growth was found to be too slow [12]. Therefore, bone tissue engineering (BTE) strategies are needed for these TiO 2 scaffolds to increase clinical translation.…”

Modularized bioceramic scaffold/hydrogel membrane hierarchical architecture beneficial for periodontal tissue regeneration in dogs

“…In general, the mechanical properties of barrier membranes should meet the clinical need to maintain structural integrity in surgery, as well as withstand forces from regenerating tissue and oral activities after surgery [46,47]. Our organic-inorganic (biphasic) hierarchical porous architectures solve the problem that the membranes absence of expected mechanical property usually fail to repair the periodontal tissue efficiently.…”

Management Of Gap Distance Around Immediate Implants With Topical Melatonin Gel and Hyaluronic Acid ( A Randomized Clinical Trial)

“…Immediate placement of implants has many advantages such as preservation of alveolar bone , better implant orientation , esthetics and psychosocial benefits in addition to it overcomes the drawbacks of delayed implants such as prolonged treatment time, multiple appointments, reduction in alveolar bone dimensions and migration of teeth into the edentulous space (25) The distance between the socket walls and the implant surface may justify augmentation to predictably achieve bone implant contact (BIC) and prevent soft tissue collapse and many preclinical and clinical studies have documented the regeneration of horizontal gaps smaller than 2 mm in the presence of a stable blood clot but when the peri-implant gap distance was more than 2mm the bone graft should be used to seal this bony defect (26)(27)(28) It was postulated that topical application of melatonin has osteoconductive capacity, stimulate new bone formation and reduce the resorption of bone by inhibiting osteoclastogenesis ( 29) Hyaluronic acid play a key role during bone repair by stimulating cell migration, adhesion, and proliferation of undifferentiated mesenchymal cells inducing their differentiation into osteoblastic cells (30) IIP in the esthetic zone represents one of the major challenges in dentistry as it implies a multidisciplinary approach involving prosthetic and periodontal aspects to gain long term stability and functional results furthermore the postextraction morphology of the maxillary premolar sockets presents a number of challenges to clinicians seeking ideal implant position, including the morphology of the lateral walls of the extraction socket and the presence of the interradicular septum in addition to thin tissue biotypes which showed greater recession than thick tissue biotypes (31) (32) According to the previous studies, the role of topical melatonin and hyaluronic acid in establishment of high success osseointegration of immediate implants and minimizing crestal bone loss needs to be investigated.…”