BACKGROUND:Bioceramic has similar components compared to human bone tissue and it has shown good ostoconductivity both in vitro and in vivo.Meanwhile,it is biocompatible.So,bioceramics is considered as one of the most promising materials which can be applied to bone tissue engineering.OBJECTIVE:To summarize the properties of bioceramics and the research progress in experimental studies and clinical applications.METHODS:PubMed was searched for relevant articles published during 2000 to 2016 with the key words of bioceramics,hydroxylapatite,calcium phosphate,bioglass,bone tissue engineering in English.RESULTS AND CONCLUSION:Bioceramic materials can be divided into two categories:calcium phosphates and bioactive glass.Calcium phosphates have good biocompatibility and osteoconductivity,while the mechanical property is not so satisfying.Bioactive glass is biocompatible and beneficial to the expression of some osteogenic genes,but it is brittle and weak.Some kinds of bioceramics have already been applied to clinical practice.In recent years,calcium phosphates have also been used as coated materials to improve the properties of tissue-engineered scaffolds.Bioceramics combined with synthetic polymers,shows better mechanical performance and biodegradation.Even so,it still has plenty of problems and challenges as a widely used bone repair material in clinical practice.

Objective To evaluate the results of the orthognathic surgery with computer aided simulation-three-dimensional(3D) printed surgical guide and dental model surgery in the treatmemt of patients with mandibular excess and facial asymmetries.Methods The coordinate system was built in ProPlan CMF 2.0 software,and the horizontal plane consisted of PoL,PoR,OrL,middle sagittal plane through nasion point and basion point and the plane perpendicular to the horizontal plane,coronoid plane through nasion point and the plane perpendicular to the horizontal plane and middle sagittal plane.The orientation of maxilla and mandibular distal segment was calculated by each triangle(U 1-U6L-U6R,L1-L6L-L6R,Me-M5L-M5R) before and after orthognathic surgery.A total of 60 mandibular excess patients with facial asymmetries were enrolled in this retrospective study.They were divided into two groups,group I with computer aided simulation,group Ⅱ with dental model surgery.The difference of maxillary occlusal plane roll and yaw angle,mandibular occlusal plane roll and yaw angle,and mandibular body plane roll and yaw angle were calculated.Statistical analysis was performed with SPSS 17.0 software.Results The yaw angle of mandibular occlusal plane of the dental model surgery and computer aided simulation was 0.36°± 0.48° and 0.84° ±0.36° (P=0.043),respectively.The roll angle of mandibular occlusal plane of the dental model surgery and computer aided simulation was 0.26°±0.79° and 0.54°±0.40°(P=0.032),respectively.The yaw angle of mandibular body plane of the dental model surgery and computer aided simulation was 0.60°± 1.04° and 0.23°±0.52°(P=0.008),respectively.The roll angle of mandibular body plane of the dental model surgery and computer aided simulation was 0.82°± 0.72° and 0.53°± 0.37° (P=0.028),respectively.The changes in computer aided simulation group were more obvious than that in the dental model surgery group,but the difference was not significant in the yaw angle of maxillary occlusal plane and the roll angle of maxillary occlusal plane between the two groups(P ＞ 0.05).Conclusions It was more effective to correct mnandibular asymmetry by computer aided simulation than dental model surgery.