Clinical study on autologus platelet-rich fibrin aided revascularization of immature permanent teeth / 北京大学学报(医学版)

OBJECTIVE@#To compare the clinical treatment efficiency of platelet-rich fibrin (PRF) assisted revascularization and traditional revascularization in immature permanent teeth.@*METHODS@#Eighteen non-vital immature permanent teeth of sixteen patients which were diagnosed as necrotic pulpitis with (or without) periapical inflammations were treated with PRF assisted revascularization. Twenty-two teeth non-vital immature permanent teeth of twenty patients which were diagnosed as necrotic pulpitis with (or without) periapical inflammations were treated with traditional revascularization. All the cases were accorded with inclusive criteria and were treated at Pediatric Dentistry of Peking University School and Hospital of Stomatology. The cases were followed up clinically and radiographically at regular intervals. Clinical examinations and periapical radiographs were recorded and analyzed. Clinical success rate was evaluated based on the clinical and radiographic findings. The changes of root length, dentine wall thickness and apical foramen width of the teeth from the two groups were measured and compared according to the preoperative and by recalling the periapical radiographs.@*RESULTS@#The cases were followed up for 6-16 months. Clinically, totally 17 out of the 18 teeth in PRF group and 21 out of the 22 teeth in traditional group were asymptomatic with no sensitivity to percussion or palpation. PRF group tended to be more effective than traditional group clinically without significant differences (P=0.446). Radiographically, 15 out of the 18 teeth in PRF group and 15 out of the 22 teeth in traditional group displayed that the roots developed, showing that root length and dentine wall thickness increased and apical foramen closed. There was a marked difference in dentine wall thickening in PRF group in comparison with traditional group (P=0.039). However, the changes of root length increasing (P=0.411) and apical foramen width closure (P=0.737) were comparable in both groups. The result in electric pulp test (P=0.517), root canal calcification (P=0.324) and crown discolor (P=0.386) were also comparable in the two groups.@*CONCLUSION@#PRF assisted revascularization and traditional revascularization in non-vital immature permanent teeth which were diagnosed as necrotic pulpitis with (or without) periapical inflammations resulted in similar clinical outcomes. Both methods showed good prognosis. PRF revascularization seemed to have better effect on dentine wall thickening than traditional method.

Association of Apa I polymorphism of vitamin D receptor gene with bone mass in men / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the association of Apa I polymorphism in vitamin D receptor (VDR) gene with bone mass in men.</p><p><b>METHODS</b>The VDR Apa I genotype was determined by PCR-restriction fragment length polymorphism (RFLP) in 388 unrelated healthy men aged 46-80 years of Han nationality in Shanghai city. Bone mineral density (BMD) and bone mineral content (BMC) at lumber spine 1-4 (L1-4) and at any sites of proximal femur including to femoral neck (Neck), trochanter (Troch) and Ward's striangle (Ward's) were measured by duel-energy X-ray absorptiometry.</p><p><b>RESULTS</b>Frequencies distribution of VDR Apa I genotype were aa for 48.1%, Aa for 44.2% and AA 7.7%. The allele frequencies of Apa I polymorphism were in Hardy-Weinberg equilibrium. No significant association was found between Apa I genotype and BMD or BMC in group of all population or in subgroup of men below 60 years. In men above 60 years, the significant association was found between VDR Apa I genotype and BMD or BMC at L1-4, Neck and Ward's (P < 0.05, P < 0.01) and compared with Aa and aa genotype, AA genotype had significantly higher mean BMD and BMC at L1-4, Neck and Ward's (P < 0.05, P < 0.01). But Apa I genotype is not associated with BMD and BMC at Troch.</p><p><b>CONCLUSIONS</b>Apa I polymorphism is associated with bone mass in men above 60 years, and AA genotype has higher bone mass. Apa I polymorphism in VDR gene possibly influence loss of trabecular and cortical bone mass in old men.</p>