Objective : To evaluate the effect of screw-retained abutment integrated crown and cement-retained in first molar tooth implant restorations． Methods : A retrospective study was conducted to select 91 patients．A total of 104 implant restorations were completed，of which 52 were screw-retained abutment integrated crown (SR) and 52 were cement-retained ( CR) ．The data of the patients on the day of implant restoration and 6th and 12th month after teeth were conducted，the bone height of the mesial and distal edges of the implants were measured，the perio- dontal clinical indexes around the implants and the patient satisfaction score were recorded at the time of reexamina- tion，and the proximal contacts after implant crown restoration was evaluated according to Barnes evaluation stand- ard. Results : 6 and 12 months after restoration，the implant retention rate in SR group and CR group was 100% ; in the screw retention group，the retention screws of 3 restorations were loosen at 6 months，and the torch force was applied to 35 N / cm ; at 12 months after restoration，the qualified rate of proximal contacts in the screw retention group was 90．38% ，which was significantly lower than that of 99. 04% in the adhesive retention group ( P = 0. 037) ．There was no difference in marginal bone absorption and periodontal soft tissue indexes mPLI and mSBI between the two groups． Conclusion The two retention methods can both achieve good implant effects，and ce- ment-retained restorations has more advantages in the first molar tooth restoration of proximal contact and the pre- vention of food impaction.

Background and purpose: Breast cancer is a group of heterogeneous diseases which has racial disparities. Our study was to elucidate the clinicopathologic features of breast carcinoma in Shanghai Han and Xinjiang Uygur women and to analyze the racial differences. Methods: In this study, 125 cases of breast invasive ductal carcinoma of Shanghai Han women and 85 cases of Xinjiang Uygur women were collected. The clinical stage was analyzed. Histological grading was observed. Immunohistochemical staining of ER, PR, HER-2, CK5/6, CK14, EGFR, Ki-67 was performed. Molecular subtypes were studied. Results:The average age of onset of breast cancer in Xinjiang Uygur women was younger than in Shanghai Han women (P<0.05), and Xinjiang Uygur women were more likely to be diagnosed at less than 35 years old (P<0.01). The proportion of stageⅠwas higher in Shanghai Han women (20.0%vs 8.2%), while the proportion of stageⅢwas higher in Xinjiang Uygur women (50.6%vs 27.2%) (P<0.01). The proportion of grade 2 was higher in Shanghai Han women (67.2% vs 43.5%), while the proportion of grade 3 was higher in Xinjiang Uygur women (47.1%vs 31.2%) (P<0.01). The proportion of luminal A subtype was higher in Shanghai Han women (36.8%vs 18.3%), while the proportion of basal-like subtype was higher in Xinjiang Uygur women (29.6%vs 12.0%) (P<0.01). The molecular subtype was associated with race and histological grade (P<0.05).Conclusion:There are racial differences in clinicopathologic features of breast carcinoma between Shanghai Han and Xinjiang Uygur women.