330 cases of impacted mandibular third molar were divided into 3 groups,A:younger than 18 years,B:18-25-year-old,C:ol-der than 25-year.Operation time(min)of group A,B and C was 21.95 ±5.86,6.45 ±4.92 and 18.77 ±9.64(B vs A or C,P <0.01), intraoperative complication rates were 2.73%,6.36% and 30.91%(P <0.01),postoperative complication rates were 51.82%,23.64%and 66.36%(P <0.05),respectively.18-25 year-old is the suitable age for removal of impacted mandibular third molars.

To study the therapeutic effect of the combination of orthodontics and fixed denture renovation preliminary in treating consecutive teeth loss. Before the fixing denture renovation,12 cases of consecutive teeth loss were treated to become interval teeth loss by using the orthodontic treatment. All patients received simultaneous functional and cosmetic restoration. The abutment teeth were healthy and the renovational teeth were stable. The combination of orthodontics and fixed denture renovation showed good effect in treating the consecutive teeth loss. It is a good clinical renovation. It is worthy to apply in clinic.

Objective: To know condom use negotiation with clients and regular sex partners and condom use in female sex workers (FSWs), and provide reference for the development of comprehensive HIV/AIDS intervention for FSWs. Methods: The cross sectional survey was conducted in Jianshui county and Mengzi county in Honghe Hani and Yi autonomous prefecture. A total of 476 FSWs aged 16 years and above were recruited from entertainment venues, and the information about their demographic characteristics, condom use negotiation and condom use were collected by using questionnaires. Logistic regression model was used to analyze related factors of condom use after negotiation between FSWs and clients unwilling use condom. Results: A total of 852 FSWs who aged (24.29±8.44) years old participated in the survey. In past month, 499 FSWs had negotiation for condom use with unwilling clients (58.6%, 499/852), after negotiation, 441 FSWs (88.4%, 441/499) had consistent condom use in each sex with the clients. In the past one month, 99 FSWs had negotiation for unwilling use condom with regular sex partners (14.4%, 99/687), after negotiation, 54 FSWs (54.5%, 54/99) had consistent condom use in each sex with regular sex partners. Among the FSWs, 266 (53.3%, 266/499) reported that they could say "It is a mandatory requirement" to persuade clients who were unwilling to use condom. 97(19.4%, 97/499) reported that they could say "There is risk for infection" to persuade clients who were unwilling to use condoms. 115 (23.1%,115/499) reported that they could say "It is a mandatory requirement" and "there is risk for infection" to persuade their unwilling clients to use condoms. 21 (4.2%, 21/499) reported that they used other strategies. 22 (4.4%, 22/499) felt that it was difficult to persuade clients to use condoms. Multivariate logistic regression analysis showed that compared with FSWs who felt difficult in persuading clients to use condoms, FSWs who felt moderate difficulty were more likely to have consistent condom use after negotiation (OR=4.00, 95%CI: 1.55-10.32) and FSWs who felt easy in persuading clients to use condoms were also more likely to have consistent condom use (OR=30.17, 95%CI: 3.22-282.44). Compared with FSWs used other strategies to persuade their clients to use condoms, FSWs who said it was a mandatory requirement were more likely to have consistent condom use after negotiation (OR=4.44, 95%CI: 1.41-14.01) and FSWs who said it was a mandatory requirement and there was risk for infection were also more likely to have consistent condom use (OR=5.52, 95%CI: 1.55-19.73). Conclusions Negotiation for condom use increased the rate of condom use in FSWs in sex with clients who were unwilling to use condom. The negotiation strategy of "It is a mandatory requirement" would promote condom use in FSWs in sex with clients who were unwilling to use condom. Besides, the negotiation strategy of saying "there is risk for infection" had additional effects.