[Analysis of clinical aesthetic effect of buccal alveolar ridge preservation and connective tissue transplantation with single implant].

PURPOSE: To evaluate the clinical aesthetic effect of buccal alveolar ridge preservation (ARP) and connective tissue transplantation (CTG) in patients who received a single implant. METHODS: Forty-three patients with tooth loss admitted to the Department of Stomatology of Shunde Hospital of Southern Medical University from May 2014 to May 2016 were included in the study. Tooth extraction, ARP, implant implantation, CTG and permanent repair were performed respectively. The incidence of bleeding, depth of probing, marginal bone resorption, and red-white aesthetic effect of implants were evaluated 1 year and 3 years after surgery. The buccal mucosa thickness of implants before, immediately after CTG, 1 year and 3 years after surgery were measured. The patient satisfaction was evaluated by visual analogue scale (VAS) from masticatory function, overall aesthetics, attachment height, and color, respectively. The implant conditions at the third year after surgery were observed, and complications during follow-up were recorded. SPSS 20.0 software package was used for statistical analysis of the data. RESULTS: The follow-up rate in the first year after surgery was 100%, and that in the third year after surgery was 90.70%. One year and 3 years after operation, the aesthetic effect of the implant was satisfactory. At the 3rd year after operation, the scores of the near middle gingival papillary were significantly higher than that at the 1st year after operation (P<0.05). The buccal mucosal thickness of the implant immediately after CTG and 1 year and 3 years after surgery increased significantly compared with that before CTG (P<0.05). The buccal mucosal thickness of the implant increased 1.02 mm (relative stability: 90.12%) 1 year after operation and 1.01 mm (relative stability: 84.31%) 3 years after operation, respectively. The satisfaction scores of the patients on chewing function, overall aesthetics, attachment height and color of the implant immediately after CTG, one year after surgery and 3 years after surgery were all > 8. The 3-year survival rate of the implants was 100%, and the 3-year success rate of the implants was 97.44%. During the follow-up, two patients developed peri-implant mucositis, which was relieved after tooth cleaning, but no complications such as tissue flap necrosis, limited opening and tongue movement disorder occurred. CONCLUSIONS: ARP and CTG have good clinical and aesthetic effects on patients with tooth loss. In three years, the buccal mucosal thickness of the implant can be increased and relatively stable, which is worthy of clinical promotion and application.

[Expression and purification of human amelogenin mature peptide in Escherichia coli].

OBJECTIVE: To establish the expression and purification route for human amelogenin mature peptide in Escherichia coli and obtain the purified amelogenin (AMG) mature peptide. METHODS: Recombined plasmid pGEX-4T-1-AMG was transformed to Escherichia coli BL21. After expression, AMG was purified with glutathione S-transferase fusion protein purification system (GSTrapFF) column. RESULTS: Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting hybridization results showed that 45,000 GST-AMG fusing protein and 19,000 target AMG mature peptide were obtained successfully. CONCLUSIONS: pGEX-4T-1-AMG-BL21 system is used successfully to express and purify human AMG mature peptide.