BACKGROUND:Research on rough-surfaced implants has demonstrated similar survival rates for short and conventional-length implants. It is not clear whether ultrashort implant in limited alveolar bone of the posterior maxila can achieve good clinical results. OBJECTIVE:To evaluate the clinical effect of ultrashort implants in limited alveolar bone of the posterior maxila. METHODS:Eighteen patients with 21 ultrashort implants in limited alveolar bone of posterior maxila (the mean residual alveolar height=3.19 mm) were included in the study, including 10 males and 8 females, aged 25-68 years. At 12 months after restoration, the patients were detected with cone-beam CT to evaluate the osseointegration and marginal bone level around the implant. RESULTS AND CONCLUSION:Al the 18 patients completed the 12-month folow-up, and the 21 pieces of implants had good osseointegration. No soft tissue inflammation was found. At 12 months after restoration, the marginal bone height in the mesial and distal was (-0.21±0.78) mm and (-0.16±0.55) mm, respectively. Implant marginal bone changes in the mesial and distal had no statistical difference (P > 0.05). Ultrashort implants in limited alveolar bone of the posterior maxila can have good osseointegration, maintain the marginal bone mass around the implant, but stil need long-term clinical observation.

We expressed B cell epitopes of dengue virus envelope protein and NS1 protein in prokaryotic cells,and purified and evaluated for its serological activities.A recombinant multi-epitope chimeric gene named rE including eight B cell epitopes was connected by linker peptide (EAAAK)2 and cloned into prokaryotic expression vector pET-28a(+),and transformed into E.coli BL21(DE3) cells for expression under induction of IPTG.The expressed recombinant protein was purified with 6× His purification media,and identified by SDS-PAGE and Western blot,and its antigenicity was analyzed by using an indirect ELISA assay.The recombinant expression vector pET28a-rE was constructed and expressed in BL21 (DE3) successfully,but the recombinant proteins mainly appeared as inclusion bodies.The target protein was obtained with high purity through the purification of affinity chromatography.SDS-PAGE and Western blot analysis showed that the molecular weight of fusion protein was in the expected line.The established indirect ELISA has high accuracy.This recombinant peptide antigen expressed in E.coli has good potential for serum testing.