This article presents an advanced dental diagnostic instrument-the pre-pain sensation electric pulp tester with current indication. The tester adopts an alternating current signal generator with a specific frequency as the stim- ulating source which can induce a pre—pain sensation similar to a cool-sour feeling or tingling without causing any pain when the current flows through the patient's dental pulp.The dentist can judge the vitality of the dental pulp by the data displ.ayed on the tester.The tester is superior to other similar instruments both at home and abroad with its better accuracy and repeatability. This instrument adopts the integrated circuit and some other new techniques such as automatic boost,automatic switching on and off of the power and automatic data-holding. Compact,light and easy to operate it has high reliability,safety and low power consumption. At present,it is a more advanced dental electric pulp tester.

Objective To investigate the prevalence of genital Chlamydia trachomatis (GCT) infection and associated risk factors in male clients attending sexually transmitted disease (STD) clinics in Guangdong and provide integrated intervention strategy for this group.Methods Convenient sampling was used to recruit participants from April to June in 2015 in Guangdong province.The information about their socio-demographic characteristics and sexual behaviors were collected by using a questionnaire,and blood samples were taken from them to test the antibodies against HIV,syphilis and HCV.First pass urine was taken to test GCT and gonorrhea.Results A total of 1 749 participants with the average age of 39.53 years were recruited.The majority of them were married (73.87％,1 292/1 749),residents of Guangdong (92.28％,1 614/1 749) and in Han ethnic group (99.49％,1 740/1 749).The positive rates for GCT,HIV,syphilis,HCV,Neisseria gonorrhea,and WBC in urinalysis were 6.06％ (106/1 749),0.46％ (8/1 749),3.43％ (60/1 749),0.45％ (7/1 550),2.74％ (48/1 749),7.89％ (138/1 749) respectively.Multivariate analysis showed that risk factors for GCT infection include IDUs (OR=13.98,95％CI:3.35-58.38),anal sex with men (OR=3.11,95％ CI:1.45-6.71),Neisseria gonorrhea positive (OR =9.64,95％ CI:5.09-18.24),and WBC positive (OR =1.96,95％ CI:1.08-3.55).Conclusions This study demonstrated the high prevalence of GCT infection in male clients attending STD clinics in Guangdong.Therefore precision intervention should target this population at high-risk.