Studies on the effect of ultrasound on properties and bonding strength of dentin smear layer / 口腔医学

Objective@# To explore the effect of ultrasound on dentin smear layer's surface and bonding strength of the universal resin adhesive under self-etching mode. @*Methods@# Forty mandibular third molars without caries were randomly divided into two groups; one was polished with silicon carbide sandpaper; the other was polished with silicon carbide sandpaper followed by ultrasonic treatment. Scanning electron microscope (SEM) was used to observe surface of the dentin. Treated teeth were bonded with two universal resin adhesives, Clearfil Universal Bond (pH=2.3) and All-Bond Universal (pH=3.1), and the penetration of the bonding interface was observed with a confocal laser scanning microscope (CLSM) after Rhodamine B staining. Finally, the micro tensile bond strength test was conducted to test the adhesion. @*Results@# The SEM showed that after polishing with silicon carbide sandpaper, the smear layer of the dentin surface was scratched, and dentin tubules were almost completely blocked, with no obvious dentin tubules exposed. After ultrasonic treatment, the scratches were reduced, and a large number of dentin tubules were exposed. CLSM showed that both adhesives could penetrate the dentin along the dentin tubules more deeply after ultrasound treatment. Micro tensile bond strength tests showed that ultrasonic treatment could enhance the bonding strength of two universal resin adhesives. However, there was no statistical difference in bonding strength between these two universal resin adhesives under the same treatment. .@*Conclusion@# Ultrasound can partially remove the smear layer on dentin's surface, expose dentin tubules, and increase universal resin adhesives' penetration depth and bonding strength under self-etching mode

Operative treatment of benign bone tumor defects in proximal joint by fibula transplantation with vascular and artificial joint replacement / 中国综合临床

Objective To explore the reconstructive methods of benign bone tumor defects in proximal joint. Methods Operative treatment was performed in 11 cases with benign bone tumor defects in proximal joint, a-mong whom 4 cases were treated by curettage,cauterization of wall and bone grafting,3 cases were treated by filling branch through segment fibula transplantation with vascular,2 cases were treated by fibula head transplantation with vascular to reconstruct the glenohumeral joint and rediocarpal joint, and 2 cases were treated by artificial joint re-placement. Results The follow-up ranged from 1.5 to 6 years. All of cases got excellent bone unioned without re-lapse and 2 cases of them developed with little limitation in joint function. Conclusion The importance and recon-structive achievement of fibula transplantation in treating the benign bone tumor defects in proximal joint should be thought fully. The indication of artificial tumor prosthesis replacement should be strictly mastered.