Impact of particulate deproteinized bovine bone mineral and porous titanium granules on early stability and osseointegration of dental implants in narrow marginal circumferential bone defects.

The use of two particulate bone graft substitute materials in experimental narrow marginal peri-implant bone defects was investigated with respect to early bone healing and implant stability. Porous titanium granules, oxidized white porous titanium granules (WPTG), and demineralized bovine bone mineral (DBBM) were characterized in vitro, after which the two latter materials were tested in experimental peri-implant bone defects in six minipigs, with empty defects as control. After mandibular premolar extraction, the top 5mm of the alveoli were widened to 6mm in diameter, followed by the placement of six implants, three on each side, in each pig. Six weeks of healing was allowed. The WPTG showed better mechanical properties. No significant differences in resonance frequency analysis were found directly after compacting or healing, and similar quantities of defect bone formation were observed on micro-computed tomography for all groups. Histomorphometric analysis demonstrated a more coronal bone-to-implant contact in the DBBM group, which also displayed more defect bone fill as compared to the WPTG group. The better mechanical properties observed for WPTG appear of negligible relevance for the early stability and osseointegration of implants.

A novel non-surgical method for mild peri-implantitis- a multicenter consecutive case series.

AIM: The aim of the present study was to evaluate the effect on peri-implant mucosal inflammation from the use of a novel instrument made of chitosan in the non-surgical treatment of mild peri-implantitis across several clinical centers. MATERIALS AND METHODS: In this 6-month multicenter prospective consecutive case series performed in six different periodontal specialist clinics, 63 implants in 63 patients were finally included. The subjects had mild peri-implantitis defined as radiographic bone loss of 1-2 mm, pocket probing depth (PPD) ≥4 mm and a positive bleeding on probing (mBoP) score. The patients were clinically examined at baseline and after 2, 4, 12 and 24 weeks, and radiographs were taken at baseline and at 3 and 6 months. Treatment of the implants with the chitosan brush seated in an oscillating dental drill piece was performed at baseline and at 3 months. Reductions in the clinical parameters (PPD and mBoP) were compared between baseline and the later examination time points. RESULTS: Significant reductions in both PPD and mBoP were observed at all time points compared with the baseline clinical measurements (p < 0.001). The mean PPD and mBoP at baseline were 5.15 mm (4.97; 5.32) and 1.86 (1.78; 1.93), respectively, whereas the mean PPD and mBoP at 6 months were 4.0 mm (3.91; 4.19) and 0.64 (0.54; 0.75), respectively. Stable reductions in PPD and mBoP were evident up to 6 months after the initial treatment and 3 months after the second treatment. All 63 implants were reported to have stable radiographic levels of osseous support. CONCLUSIONS: This case series demonstrated that an oscillating chitosan brush is safe to use and seems to have merits in the non-surgical treatment of dental implants with mild peri-implantitis. To measure the effectiveness of the method, a multicenter randomized clinical trial needs to be undertaken.

Enamel matrix proteins; old molecules for new applications.

Emdogain (enamel matrix derivative, EMD) is well recognized in periodontology, where it is used as a local adjunct to periodontal surgery to stimulate regeneration of periodontal tissues lost to periodontal disease. The biological effect of EMD is through stimulation of local growth factor secretion and cytokine expression in the treated tissues, inducing a regenerative process that mimics odontogenesis. The major (>95%) component of EMD is Amelogenins (Amel). No other active components have so far been isolated from EMD, and several studies have shown that purified amelogenins can induce the same effect as the complete EMD. Amelogenins comprise a family of highly conserved extracellular matrix proteins derived from one gene. Amelogenin structure and function is evolutionary well conserved, suggesting a profound role in biomineralization and hard tissue formation. A special feature of amelogenins is that under physiological conditions the proteins self-assembles into nanospheres that constitute an extracellular matrix. In the body, this matrix is slowly digested by specific extracellular proteolytic enzymes (matrix metalloproteinase) in a controlled process, releasing bioactive peptides to the surrounding tissues for weeks after application. Based on clinical and experimental observations in periodontology indicating that amelogenins can have a significant positive influence on wound healing, bone formation and root resorption, several new applications for amelogenins have been suggested. New experiments now confirm that amelogenins have potential for being used also in the fields of endodontics, bone regeneration, implantology, traumatology, and wound care.