Objective To analyze the anatomical relationship between maxillary premolars and the alveolar bone and maxillary sinus using cone-beam computed tomography(CBCT),in order to provide an anatomical basis for immediate implant placement in maxillary premolars.Methods Data from 351 patients who underwent maxillary CBCT imaging at Yancheng Stomatological Hospital between January 2022 and December 2023 were collected.Measurements included the vertical distance between premolar roots and the maxillary sinus floor,intraosseous root length,angle between the tooth axis and alveolar bone axis,and buccal/palatal bone wall thickness,with comparisons of gender differences.Results The median vertical distance between single-rooted maxillary first premolars and the maxil-lary sinus floor was 10.16 mm,while that for second premolars was 4.61 mm.For double-rooted first premolars,the buccal root dis-tance was(4.13±3.99)mm and the palatal root was(5.14±3.94)mm.Maxillary first premolars were farther from the maxillary sinus floor than maxillary second premolars,with palatal roots farther than buccal roots.The intraosseous root length of maxillary first premo-lars was(9.20±1.44)mum,and maxillary second premolars(9.64±2.04)mm.Maxillary first premolars exhibited significantly shorter intraosseous root length than maxillary second premolars.The angle α between tooth axis and alveolar bone axis was 18.89°±6.33° for maxillary first premolars,and 12.65°±6.10° for maxillary second premolars,showing statistically significant differences.The buccal bone wall thickness of maxillary first premolars gradually decreased from 2 mm subcrest to the apex,while palatal bone walls of maxil-lary first premolars and both buccal/palatal walls of maxillary second premolars progressively thickened from 2 mm subcrest to the apex.Significant correlations were identified between angle α and buccopalatal bone wall thickness at mid-root and the apex:increased α cor-responded with reduced buccal wall thickness and enhanced palatal wall thickness.Conclusion The apical region of maxillary first premolars provides sufficient bone volume for primary stability in immediate implantation,though the thin buccal bone wall necessitates careful consideration of implant shape and positioning.Maxillary second premolar roots are closely adjacent to the maxillary sinus floor,requiring implant stabilization with the sinus floor cortical bone or me-siodistal walls of the extraction socket.

Objective To analyze the anatomical relationship between maxillary premolars and the alveolar bone and maxillary sinus using cone-beam computed tomography(CBCT),in order to provide an anatomical basis for immediate implant placement in maxillary premolars.Methods Data from 351 patients who underwent maxillary CBCT imaging at Yancheng Stomatological Hospital between January 2022 and December 2023 were collected.Measurements included the vertical distance between premolar roots and the maxillary sinus floor,intraosseous root length,angle between the tooth axis and alveolar bone axis,and buccal/palatal bone wall thickness,with comparisons of gender differences.Results The median vertical distance between single-rooted maxillary first premolars and the maxil-lary sinus floor was 10.16 mm,while that for second premolars was 4.61 mm.For double-rooted first premolars,the buccal root dis-tance was(4.13±3.99)mm and the palatal root was(5.14±3.94)mm.Maxillary first premolars were farther from the maxillary sinus floor than maxillary second premolars,with palatal roots farther than buccal roots.The intraosseous root length of maxillary first premo-lars was(9.20±1.44)mum,and maxillary second premolars(9.64±2.04)mm.Maxillary first premolars exhibited significantly shorter intraosseous root length than maxillary second premolars.The angle α between tooth axis and alveolar bone axis was 18.89°±6.33° for maxillary first premolars,and 12.65°±6.10° for maxillary second premolars,showing statistically significant differences.The buccal bone wall thickness of maxillary first premolars gradually decreased from 2 mm subcrest to the apex,while palatal bone walls of maxil-lary first premolars and both buccal/palatal walls of maxillary second premolars progressively thickened from 2 mm subcrest to the apex.Significant correlations were identified between angle α and buccopalatal bone wall thickness at mid-root and the apex:increased α cor-responded with reduced buccal wall thickness and enhanced palatal wall thickness.Conclusion The apical region of maxillary first premolars provides sufficient bone volume for primary stability in immediate implantation,though the thin buccal bone wall necessitates careful consideration of implant shape and positioning.Maxillary second premolar roots are closely adjacent to the maxillary sinus floor,requiring implant stabilization with the sinus floor cortical bone or me-siodistal walls of the extraction socket.

Objective To investigate the comprehensive effect and impact path of family environment,rearing style and personality on adolescents with mental disorder.Methods A sample of 200 adolescents with mental disorders and 228 normal adolescents were tested with Family Environment Scale (FESCV),Family Upbringing Style Questionnaire (FUSO),Big Five Personality Questionnaire (NEO-FFI-R) and Psychological Symptom Inventory-100(PSI-I00).Regression analysis and path analysis were used to explore influence and path of rearing style,family environment and personality on mental health.Results The total score PSI-100 in case group (204.0±68.6) was higher than that in control group (146.9±38.4)(t=10.43,P＜0.01).Regression analysis revealed that mental health was affected by rearing style (R2 =0.208) such as mother supervision-control (β =-0.249),father understands-blame (β =-0.195),mother warmth-wildness (β=-0.228) and mother acceptance-rejection (β=0.201),family environment (R2 =0.244) such as conflict (β=0.309),organization (β=-0.196) and expressiveness (β=-0.141),and personality traits (R2 =0.452)such as neuroticism (β=0.412),agreeableness (β=-0.237) and conscientiousness (β=-0.203).Path Analysis showed that personality traits directly affected mental health (β=-0.90),parenting style indirectly influenced mental health (β=0.51) by personality,the family environment had direct (β=0.20) and indirect (β=0.72) effects on mental health,and the model fits well (x2/df =2.160,RMSEA =0.052,GFI =0.88,AGFI =0.84,PGFI =0.67,NFI =0.91,RFI =0.89,IFI =0.95,TLI =0.94,CFI =0.95),and three factors explained 61％ of variation on symptom total score.Conclusion The family environment,family upbringing style and personality traits have significant effect on the adolescent's mental disorder.The personality traits are the most important variables affecting mental health family upbringing style affect mental health indirectly through personality traits,and family environment directly and indirectly affected on the mental health.

Objective To explore family environment,parenting style,and personality of the patients with internalizing and externalizing mental disorders.Methods 137 adolescents with internalizing mental disorder(IMD),63 adolescents with externalizing mental disorder(EMD) and 228 normal subjects (control group) were investigated with Family Environment Scale-Chinese Version (FES-CV),Family Upbringing Style Questionnaire (FUSQ) and the NEO Five Factor Inventory (NEO-FFI).Results (1) The IMD group scored significantly lower on the cohesion (6.17 ± 2.68),active recreational orientation (3.84 ±2.50),moral-religious emphasis (4.48± 1.65),organization (5.35±2.30),expressiveness (4.60±2.00),achievement orientation (5.31 ± 1.84),and higher on the conflict (4.01 ± 2.38) than control group (P＜ 0.05).The EMD group scored only higher on the conflict (4.01±2.38) than control group (P＜0.05).(2) The all dimensional scores(apart from the parent's expect-demanding) of the IMD group were significantly lower than that of control group on the FUSQ (P＜0.05).The scores on the mother's democracy-authoritarian,parent care-protect,catholic-indulgences,parental-control,and expect-demanding were significantly lower in the EMD group than those in the control group (P＜0.05).(3) Relative to the control group,the IMD group got lower scores on the agreeableness (42.02±5.01),conscientiousness (38.91±8.01),and extraversion (35.17±8.57),and higher score on the neuroticism (40.10±8.55);the EMD group got lower scores on the agreeableness(42.75±5.12),conscientiousness (39.95±8.27) and openness (40.00±6.75).Conclusion Adolescents with mental disorders are living in conflict and discord family environment,feel more negative parenting such as authoritarian,harsh,indulgence,control,and demanding,and show some unhealthy personality such as low agreeableness,low conscientiousness,and high neurotic.

Aim To investigate the preventive effect of Polygonum Multiflorum (PM)on the deteriorated mi-cro-structure and biomechanical properties induced by prednisone.Methods Ninety 6-month-old male Sprague-Dawley rats were randomly divided into nine groups,which were control,prednisone,CAL,30%ethanol eluent of the PM(H,M,L),PM(H,M,L). Prednisone was gavaged to rat for 21 weeks as model group of osteoporosis.Meanwhile,tested herbal ab-stract were orally administrated to the modeled rats in-duced by prednisone.At the end of the experiment, the right femur was collected for micro-CT scanning, three-dimensional reconstruction and biomechanical test.Results Compared with the control group,mod-el group showed destruction of bone microarchitecture, BV /TV fell 28.6%(P <0.05),bone biomechanical parameters decreases,and stiffness fell 29.7%(P <0.01 ). Compared with the model group, positive group had significantly improved effect on bone micro-architecture,and biomechanical parameters,BV /TV increased 46.7%(P <0.01 ),and stiffness increased 25.9%(P <0.01 ).30% ethanol eluent of the PM (M,L)dose may improve bone microstructure by in-creasing BV /TV 46.7% (P <0.01 ),40.0% (P <0.05)respectively,PM(H)may improve the biome-chanical parameters by increasing stiffness 24.7%(P<0.05),and 30% ethanol eluent of the PM(H)and PMhigh-dose may improve the biomechanical parame-ters,but not as positive group.Conclusions Predni-sone reduces biomechanical properties of rat femur and deteriorates femoral microstructure.30% ethanol eluent of the PM(M,L)and PM(H)plays a preventive role in the changes of micro-structural and biomechanical properties by prednisone,and increases BMD,whereas other groups have no significant preventive effect.