OBJECTIVETo study the clinical manifestation and its pathogenesis of the developmental enamel defects in primary dentition of children with low birth weight and premature birth history.

METHODSOne hundred and seventy-six children (aged 3-8 years old) were studied about the clinical manifestation of the developmental enamel defects in the primary dentition and its relationship with their medical history.

RESULTSThe prevalence of enamel defects in primary dentition in these children was 77.3%. There was no significant correlation between enamel defects and gender. Enamel opacity mostly affected the upper and lower second primary molars. Enamel hypoplasia mostly affected the maxillary and mandibular primary incisors and the maxillary first primary molars.

CONCLUSIONEnamel defects mainly result from children's general disorder at birth or within one year after birth.

Child ; Child, Preschool ; China ; epidemiology ; Dental Enamel ; abnormalities ; Dental Enamel Hypoplasia ; diagnosis ; epidemiology ; Female ; Humans ; Infant, Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Male ; Molar ; abnormalities ; Prevalence ; Tooth, Deciduous ; abnormalities

Objective:To explore the effects of internet-based group cognitive-behavioral therapy(IGCBT)on the depressive and anxiety symptoms in patients with major depressive disorder(MDD).Methods:Eighty pa-tients with MDD were recruited and randomly divided into IGCBT combined drug therapy group and control group with drug therapy.Blind assessments were performed using the Hamilton Depression Scale(HAMD)and Hamilton Anxiety Scale(HAMA)three times at baseline,4 weeks after treatment and 8 weeks after treatment,respectively.Results:The effective rates of HAMD and HAMA at the end of the 4th and 8th week,and the effective rates of HAMA at the end of the 8th week were higher in the combined treatment group than those in the control group(Ps＜0.05).The total scores of HAMD and HAMA in the combined treatment group and the control group were lower at the end of the 4th and 8th week than those at baseline(Ps＜0.001).The total scores of HAMD and HAMA were lower in the combined treatment group than those in the control group at the baseline,4 weeks and 8 weeks after treatment(Ps＜0.01).Conclusion:It suggests that intemet-based group cognitive-behavioral therapy combined with antidepressant medication has a better effect on relieving depressive and anxiety symptoms in patients with ma-jor depressive disorder than drug therapy alone,and especially has a better effect on improving anxiety symptom.