Objective:To analyze the prognosis of replanted permanent teeth in children and associated factors. To determine the onset time of root resorption and related factors. Methods: Clinical data of replanted teeth treated in Department of Pediatric Dentistry, Peking University, School and Hospital of Stomatology, from January 2000 to December 2006,were collected, and the follow-up period was no less than six months. The Fisher's exact test and cox regression were used for statistical analysis. Results: The study comprised of 39 patients with 50 replanted permanent teeth. The periodontium healing rate was 18%, while root resorption rate was 82%. Replacement resorption was the most common type of root resorption (64%).The factors significantly affecting periodontium healing were stage of root development and storage of avulsed teeth.Stage of root development and the time of endodontic treatment significantly affected the onset time of root resorption(P<0.05). Conclusion: Replacement resorption is the most common type of root resorption. The factors significantly affecting periodontium healing are stage of root development and storage of avulsed teeth. Stage of root development and the time of endodontic treatment significantly affect the onset time of root resorption.

Objective To understand the association between rs1079727 polymorphism in the DRD2 gene and the distractibility in the school-age children.Method The rs1079727 polymorphisms were genotyped using Sequenom Mass Array and the distractibility was measured based on the Middle Childhood Temperament Questionnaire (MCTQ) in 121 children aged from 8 to 12 years,in order to analyze the function of rs1079727 polymorphism and its interaction with gender or the delivery mode on the distractibility.The results were analyzcd with oneway ANOVA and logistic regression analysis.Results There was association between the distractibility and rs1079727 polymorphism or delivery mode respectively.The means of distractibility for the genotypes of GG (4.37 ±0.53) and AG (4.27±0.69) were significantly higher than that of the genotype of AA(4.01±0.67) (P＜0.05).The proportion of high distractibility in the cesarean children (48.28％) was significantly higher than that in the natural labor children (33.90％) (P＜0.05).The child distractibility occurred through an interaction between rs1079727 polymorphism and gender/delivery mode.The girls with G alleles possessed increased risk of distractibility (OR=2.231,P＜0.05),and the natural labor children with A alleles were tend to be associated with low distractibility(OR =0.048,P＜0.01).Condusion The distractibility based the temperament for the school-age children might be influenced by delivery mode,rs1079727 polymorphism and its interaction with gender/delivery mode.

Background Flicker light can induce myopia,but its mechanism remains unclear.As one of immediate early genes,early growth response-1 (Egr-1) gene can generate rapid response to visual stimulation,however,its effect on the formation and development of myopia is below understood.Objective This study was to investigate the dynamic expression of Egr-1 gene in retinas of flicker light-induced eyes (FL) and compare the results with form deprived eyes (FD).Methods One hundred and fifty 28-day-old C57BL/6J mice were randomly assigned to the normal control group,FD group and FL group.The right eyes of mice were occluded with a semitransparent hemispherical thin plastic shell for 2 weeks in the FD group,and the right eyes of mice were stimulated by 2 Hz flicker light for 2 weeks in the FL group,and then the mice were fed in the normal light environment for 1 week.The refractive state and axial length of the model eyes were measured by murine-specific eccentric infrared photorefraction and A-scan ultrasonography before modeling and 1 hour,I day,1 week,2 weeks after modeling as well as 1 week after termination,respectively.The mice were sacrificed in above-mentioned time points to isolate the retinas.The expressions and location of Egr-1 protein and mRNA in the retinas were detected by Western blot,and reverse transcription PCR (RT-PCR) and immunochemistry.The expressions of Egr-1 markers,neuron and protein kinase C (PKC)-α,in the retinas were assayed by using immunofluorescence.The care and use of the animals followed the administration regulations for experimental animals of Jiangsu Province.Results Two weeks after modeling,the refraction of the FL group was (0.32±0.14) D,which was significantly lower than (-0.66±0.43)D in the FD group (t=6.78,P=0.00).One hour after modeling,The expression levels of Egr-1 mRNA in mouse retinas were 0.626±0.044 and 0.695±0.058 in the FD group and FL group,which were significantly declined in comparison with 1.009±0.089 of the normal group (t=14.81,P=0.01;t=9.15,P=0.03).In 2 weeks after modeling,the expression levels of Egr-1 mRNA were still lower in the FD group and F:L group compared with the normal group (all at P＜0.05).However,the expression levels were significantly elevated in the FD group and FL group compared with the normal group (t=4.13,P=0.01;t=4.26,P=0.01) at 1 week after termination.Western blot showed a dynamic decrease in the expressions of Egr-1 protein with lapse of time in the FD group and FL group with the lowest expressing level in the second week after modeling.In I week after termination of modeling,the expressing level was raised in the FD group or the FL group,but it was still lower than that ir the normal group (t =6.32,P=0.00;t =5.45,P=0.01).Egr-1 protein was mainly expressed in the retinal ganglion cell (RGC) layer,inner nuclear layer and photoreceptor layer in the normal mice,and the expression intensity was obviously weaker in the FD mice and FL mice 2 weeks after modeling.Htowever,the expression was enhanced in 1 week after termination of modeling.Neuron and PKC-α were strongly expressed in the RGCs and bipolar cells in the normal mice.Conclusions The eyes show a myopic trend after induce of flicker light in B6 mice.The expression level of Egr-1 gene in the retina down-regulates with the reduce of refraction in FL eyes,and its dynamic expressing change is consistent between the FD eyes and FL eyes.

OBJECTIVE:To study the development and status quo of narcotics and psychotropic substances (NPS) in China since 1949,and to provide evidence for perfection of NPS control work in China. METHODS:The development and status quo of controlled substances control by China since 1949 were summarized and analyzed through retrieving and collecting literatures,re-ports and policies about NPS from domestic and foreign databases,news reports and related website. RESULTS & CONCLU-SIONS:Chinese narcotics and psychotropic substances control dated back to the release of Interim Regulations on Narcotics Con-trol in 1950 and Regulations on Narcotics Control,Drug Administration Law and other regulations have been issued. It had experi-enced the progress from no legal basis to having laws to follow and from executive-leading to legalization. Narcotics and psychotro-pic substances were gradually unified in systematic control,and the level of regulations rised from department rules to administra-tion regulation. At present,with Regulations on Narcotics and Psychotropic Drugs Control (2005) as regulatory basis and cata-logue of narcotics and psychotropic substances(2013)as object,China Food and Drug Administration are in charge of the national regulation,cooperating with health department,agricultural department,traffic department and other departments.

OBJECTIVE:To study the development and status quo of controlled drugs control in Britain,and to provide evi-dence for narcotics and psychotropic substances(NPS)control in China. METHODS:The development and status quo of NPS con-trol by Britain were summarized and studied through retrieving and collecting literatures,reports and policies about NPS from do-mestic and foreign databases,news reports and international website. RESULTS & CONCLUSIONS:British control for controlled drugs dated back to Pharmacy Act in 1868,and Britain was the first country to control drugs by legislations. A unique British sys-tem of narcotics control was established and improved after issued Rolleston Report and two pieces of Brain Report in Britain. Final-ly,the British system of narcotics control was established,which combined public health prevention with judicial redress. At pres-ent,controlled drugs are classified and controlled by Advisory Committee on Drug Abuse,Serious Organised Crime Agency and National Drug Abuse Treatment Agency subordinated to Ministry of Interior,based on Misuse of Drugs Act.

OBJECTIVE:To study the development and status quo of controlled substances control in the United States,and to provide evidence for narcotics and psychotropic substances (NPS) control in China. METHODS:The development and status quo of controlled substances control by the United States were summarized and studies through retrieving and collecting literatures,re-ports and policies about NPS from domestic and foreign databases,news reports and international website. RESULTS & CONCLU-SIONS:The United States'control for controlled substances dated back to Harrison Narcotics Tax Act in 1914,and the United States is the first nation to control narcotics addiction through the form of tax law after International Opium Convention is executed. Thereafter,the United States gradually extend the range by including cannabis,heroin and psychotropic substances into control range of Narcotics Drugs Import and Export Act,Heroin Act,Marijuana Tax Act,revising and developing comprehensive act Con-trolled Substances Act,and establishing comprehensive law enforcement agency Controlled Substances Enforcement Administration affiliated to Ministry of Justice by Nixon'sWar on Drugsplan.

OBJECTIVE:To study the development and status quo of international narcotics and psychotropic substances (NPS)control,and to provide evidence for NPS control in China. METHODS:The development and status quo of NPS control by international organization were summarized and studied through retrieving and collecting literatures,reports and policies about NPS from domestic and foreign databases,news reports and international website. RESULTS & CONCLUSIONS:International narcot-ics control dated back to opium trade with China in 19th century. International narcotics control system was established preliminarily by Shanghai conference and Haiya conference. The end of World War Ⅰ,the establishment of the League of Nations and the sign-ing of a number of international treaties promoted the development of internal control system. Through World War Ⅱ,the establish-ment of the United Nations and the change of international control organization,a number of international treaties were integrated into Single Convention on Narcotic Drugs in the early 1960s,which was used as the foundation of narcotics control system all round the world. In 1970s,the adoption of Convention on Psychotropic Substances meant psychotropic substances were included in the scope of internal control. In 1980s,the signing of United Nations Convention against Illicit Traffic in Narcotic Drugs and Psy-chotropic Substances marked the establishment of three conventions system of international NPS control. At present,internal NPS control is based on three conventions system and NPS list by Commission on Narcotic Drugs,International Narcotics Control Board and United Nations International Drug Control Program. The vast majority of countries are parties to that. International control orga-nizations and listed control have a great influence on NPS control all round the world.

OBJECTIVE:To make proposals to improve narcotics and psychotropic substances(NPS)control in China. METH-ODS:NPS control system of international organizations,the United States,Britain and China were compared in terms of concept, classification,regulatory basis and agency,etc. The suggestions and reference were put forward. RESULTS & CONCLUSIONS:NPS of international organizations,the United States,Britain and China are drug types included in relevant categories,besides ana-leptics,precursor chemicals and other drugs are included in control catalogue by the United States and Britain. NPS are divided in-toⅠ-Ⅳcategories by international organizations,Ⅰ-Ⅴcategories by the United States,A,B,C categories and temporary catego-ry by Britain,and narcotics,first and second class psychotropic substances by China. NPS control basis of the United States,Brit-ain and China are Controlled Substances Act,Misuse of Drugs Act and Regulations on Narcotics and Psychotropic Drugs Control, respectively;major regulation organizations are Controlled Substances Enforcement Administration,Advisory Committee on Drug Abuse subordinated to Ministry of Interior,Special Drug Section under China Food and Drug Administration,respectively;there al-so are differences in the functions of control organization and cooperative units. Considering about the problems of NPS control in China,it is suggested to improve laws and regulations system,establish independent system,extend abuse surveillance network and encourage chronic non-cancer pain therapy.

OBJECTIVETo evaluate the prognosis of luxated permanent teeth and analyze the associated factors of pulp healing after luxation injuries.

METHODSThe dental records of patients presented for treatment due to luxation injuries at the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology from January 2000 to December 2006 were collected, and the follow-up period was not shorter than six months. The following information was recorded, age and gender; type of injury; location of injured tooth; stage of root development; time elapsed between the injury and the first dental care; emergency treatment or not; pulp healing. Logistic regression was used to compare qualitative data and determine the associated factors of pulp healing after luxation injuries.

RESULTSThe study was comprised of 157 patients with 238 luxated permanent teeth. The frequency of pulp necrosis was 16.0%, dental pulp calcification 2.1% and pulp survival 81.9%. The frequency of pulp necrosis was highest in intrusion (66.7%). The factors significantly affecting pulp healing were stage of root development and type of injury.

CONCLUSIONSThe risk of pulp necrosis was greatest in intrusion. The stage of root development and the type of injury were significant factors related to pulp healing after luxation injuries.

Adolescent ; Child ; Child, Preschool ; Dental Pulp ; injuries ; Dental Pulp Calcification ; diagnosis ; etiology ; Dental Pulp Necrosis ; diagnosis ; etiology ; Female ; Humans ; Male ; Prognosis ; Retrospective Studies ; Tooth Avulsion ; complications ; diagnosis ; therapy

OBJECTIVETo analyze the prognosis of uncomplicated crown fractures and the related factors.

METHODSClinical data of uncomplicated crown fractures treated in Department of Pediatric Dentistry, Peking University School of Stomatology from 2000 to 2006 were collected, and the follow-up period was not shorter than six months. The following information was recorded, including patients' age and gender, type of injury, with or without luxation injury, location of injured tooth, stage of root development, time elapsed between the injury and the first dental care, emergency treatment or not, pulp healing. Logistic regression was used for statistical analysis.

RESULTSThe study comprised of 307 patients with 415 uncomplicated crown-fracture teeth. The frequency of pulp necrosis was significantly higher in crown-fracture teeth with luxation injuries (34.0%) than in crown-fracture teeth without luxation injuries (22.7%) (P < 0.05). Age of patients and type of injury were significantly related to pulp prognosis in crown-fracture teeth without luxation injuries. While stage of root development and type of injury were significantly related to pulp prognosis in crown-fracture teeth with luxation injuries.

CONCLUSIONLuxation injuries was significantly related to the prognosis of uncomplicated crown-fracture teeth.

Child ; Crowns ; Dental Pulp ; Dental Pulp Necrosis ; Humans ; Incisor ; Male ; Retrospective Studies ; Tooth Avulsion ; Tooth Crown ; Tooth Fractures ; Tooth Root