Objective: To observe the effects of radiographic exposure on marginal microleakage for treating dental caries with Filtek Z350 nano resin and FX-Ⅱ reinforced glass ionomer cement. Methods: 40 premolars were randomly divided into four groups with 10 teeth in each group: radiographic exposure group A1 and A2,control group B1 and B2. Cavities were prepared on the buccal side of all the teeth, then the teeth in group A1 and B1 were filled with Filtek Z350 nano resin, and the teeth in group A2 and B2 were filled with FX-II reinforced glass ionomer cement. The teeth in group A1 and A2 were irradiated once a day and 2.0Gy a time, and the total exposure was 70Gy; While the teeth in group B1 and B2 were not irradiated. All the teeth were dyed with 2.0% methylene blue solution after 500 times thermocycling, and the microleakage depth were measured under somatic microscope. Results: Filled with same filling materials, there was no significant difference in microleakage depth between radiographic exposure group and control group (P>0.05). Radiation or not, there was no significant difference in microleakage depth between different filling materials (P>0.05). Conclusions: For patients with head and neck tumor who are prepared for radiotherapy in clinic, Filtek Z350 nano resin and FX-Ⅱ reinforced glass ionomer cement can be used to treat dental caries, they all can obtain fairly stable edge sealing effects.

Objective: To observe the effects of alprostadil, salvianolate and Erigeron breviscapus after replantation of severed finger. Methods: 90 patients with replantation of severed finger were randomly divided into the following 3 groups (n=30): alprostadil group (A group), salvianolate group (B group) and Erigeron breviscapus group (C group). All the patients underwent replantation of severed fingers under brachial plexus block anesthesia, and received routine treatment such as three antibodies and limb heat preservation after operation. The survival rate of finger replantation, vascular crisis, adverse reactions, as well as prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (APTT), fibrinogen (FIB), platelet (PLT) 1 day and 7 days after operation of patients in 3 groups were compared. Results: The survival rate of finger replantation of A group was obviously higher than other 2 groups, but the incidence of vascular crisis of A group was obviously lower than other 2 groups (P˂0.05). There was no significant difference in PT, INR, APTT, FIB and PLT among the 3 groups 1 day and 7 days after operation (P>0.05). The PT, INR, APTT, FIB of patients in 3 groups 7 days after operation were all significantly higher than that 1 day after operation (P˂0.05); but the PLT 7 days after operation was significantly lower than that 1 day after operation (P˂0.05). There was no significant difference in incidence of adverse reactions among the 3 groups (P>0.05). Conclusions: The effects of alprostadil is better than salvianolate and Erigeron breviscapus after replantation of severed finger, so it is worthy of clinical promotion.

Objective: To investigate the effects of different tooth preparation methods on ultrastructure of non-carious sclerotic dentine. Methods: 20 molar teeth with typical sclerotic dentin on the occlusal surface were randomly divided into 4 groups: Teeth in group A were prepared with high-speed turbine dental drill; Teeth in group B were prepared by dental drill and 35% phosphoric acid for 15s; Teeth in group C were prepared by Er,Cr:YSGG laser; Teeth in group D were prepared by laser and 35% phosphoric acid for 15s. Scanning electron microscope was used to observe the ultrastructure of the sclerotic dentin surface. Results: Group A: the sclerotic dentin surface was relatively flat, and covered by smear layer. Group B: the sclerotic dentin surface became rough, the smear layer had been removed and sclerotic column protruded from dentinal tubules. Group C: the sclerotic dentin surface was rough, the intertubular dentin were honeycombing changed, and the dentinal tubules protruded. Group D: the opening of dentinal tubules increased and sclerotic column protruded. Conclusions: Prepare the dentin surface by Er,Cr:YSGG laser can obviously improve the non-carious sclerotic dentine surface, combined 35% phosphoric acid etching at the same time can obtain a better bonding surface.