Locking system strengthened by biomimetic mineralized collagen putty for the treatment of osteoporotic proximal humeral fractures.

The current study is to observe the effect of the locking system strengthened by biomimetic mineralized collagen putty for the treatment of senile proximal humeral osteoporotic fractures. From January 2012 to December 2015, 80 cases of senile patients with osteoporotic proximal humeral fractures were randomly divided into an observation group and a control group, each group with a total of 40 cases. The control group was simply treated with locking plate. The observation group was treated with locking plate in combination with biomimetic mineralized collagen putty. The therapeutic effect thereby was observed. The excellent and satisfactory rate was 90% in observation group and was 72.5% in control group. The difference between the two groups was statistically significant (χ2 = 5.3312, P < 0.05). The fracture healing time was 11.82 ± 3.62 weeks in observation group and 19.78 ± 5.46 weeks in control group. The shoulder joint function score was 89.63 ± 8.12 in observation group and 76.92 ± 8.18 in control group. There was significant difference between the two groups (t = 7.1272; 12.7834, P < 0.05). The complication rate was 10% in the observation group and 32.5% in the control group (χ2 = 7.3786, P < 0.05). Locking system strengthened by biomimetic mineralized collagen putty has advantages such as accelerating healing of senile proximal humeral fracture, improving the therapeutic effect, reducing the complications. As one of the optimal internal fixation method, it provides a new option for better treatment of senile osteoporotic fracture.

Clinical evaluations of mineralized collagen in the extraction sites preservation.

The purpose of this study was to explore the different effects between biomimetic mineralized collagen (MC) and ordinary physically blended hydroxyapatite/collagen (HA/Col) composite in evaluating new bone formation and regenerated bone height in human extraction sockets. Thirty-four patients who cannot retain teeth caused by trauma or decay were randomly selected from Department of Stomatology of Dongzhimen Hospital from December 2013 to December 2014. The patients were randomly divided into two groups. After the operation of tooth extraction, 17 patients were implanted with biomimetic MC (MC group), and other 17 patients were implanted with ordinary physically blended nHA/Col composite (nHA/Col group). X-ray positioning projection by auto-photographing was taken to test the distance between the lowest position and the neighboring CEJm-CEJd immediately, 1 month and 3 months after the operation. The height of new bone formation of the MC group was significantly higher than the nHA/Col group. Biomimetic MC showed better clinical outcomes in the bone formation for extraction site preservation and would have broad application prospect in the field of oral and maxillofacial surgeries.

Test in canine extraction site preservations by using mineralized collagen plug with or without membrane.

The aim of this study was to discuss the feasibility of porous mineralized collagen plug and bilayer mineralized collagen-guided bone regeneration membrane in site preservation in extraction sockets. The third mandibular premolars on both sides were extracted from four dogs, thus there were 16 alveolar sockets in all dogs and were randomly assigned into three groups. Group A had six alveolar sockets, and groups B and C had five alveolar sockets, respectively. Each alveolar socket of group A was immediately implanted with a porous mineralized collagen plug and covered with a bilayer mineralized collagen-guided bone regeneration membrane after tooth extraction. Alveolar sockets of group B were implanted with porous mineralized collagen plug only, and group C was set as blank control without any implantation. The healing effects of the extraction sockets were evaluated by gross observation, morphological measurements, and X-ray micro-computed tomography after twelve weeks. Twelve weeks after operation, both groups A and B had more amount of new bone formation compared with group C; in terms of the degree of alveolar bone height, group A was lower than groups B and C with significant differences; the bone mineral density in the region of interest and bone remodeling degree in group A were higher than those of groups B and C. As a result, porous mineralized collagen plug could induce the regeneration of new bone in extraction socket, and combined use of porous mineralized collagen plug and bilayer mineralized collagen guided bone regeneration membrane could further reduce the absorption of alveolar ridge and preserve the socket site.

A novel combination of nano-scaffolds with micro-scaffolds to mimic extracellularmatrices improve osteogenesis.

To improve bone engineering for clinical applications, we coupled nanofiber-peptide hydrogel to nano-hydroxyapatite/collagen to form a bioactive scaffold (cnHAC) that mimics extracellular matrices. In comparison to nano-hydroxyapatite/collagen, we found that cnHAC promoted cell adhesion and spreading, and DNA content measurements, alkaline phosphatase activity assays, and reverse transcriptase-polymerase chain reaction analyses of osteogenic gene expression showed that cnHAC significantly improved cellular attachment, proliferation, and osteogenic differentiation in vitro (P < 0.05). In vivo models based on rat calvarial implants showed that cnHAC significantly enhanced bone regeneration (P < 0.05). In conclusion, we demonstrated that novel cnHAC scaffolds could potentially facilitate future bone regenerative medicine.