Objective To investigate the prediction of diffusion kurtosis imaging(DKI)and intra voxel incoherent motion(IVIM)imaging global histogram parameters for the efficacy of neoadjuvant chemotherapy(NAC)in patients diagnosed with breast invasive ductal carcinoma.Methods A total of 69 patients with breast invasive ductal carcinoma confirmed by penetration pathology were retrospectively selected.Prior to undergoing NAC,all patients underwent sequential scans including MR conventional(T1WI,T2WI),dynamic contrast enhancement(DCE),DKI,and IVIM.After surgery,the patients were divided into significant group(40 patients)and non-significant group(29 patients)based on the efficacy of NAC,which was evaluated using the Miller-Payne(MP)grading method criteria.The differences in global histogram parameters of DKI[mean diffusivity(MD),mean kurtosis(MK)]and IVIM(D value,f value,D*value)between the significant group and the non-significant group were compared by the two-independent sample t-test and Mann-Whitney U test.In addition,the receiver operating characteristic(ROC)curve was plotted,and Spearman rank correlation analysis was used to evaluate the diagnostic efficacy and correlation of DKI and IVIM global histogram parameters in predicting NAC efficacy.The DeLong test was used to compare whether there was statistical significance in area under the curve(AUC)differences among histogram parameters.Results The DKI MD value(90th percentile,mean,median,maximum,range,root mean square),IVIM D value(mean,range,root mean square,median)and D*value(entropy,90th percentile)of patients with breast invasive ductal carcinoma in the significant group with efficacy of NAC were higher than those in the non-significant group,while the DKI MK value(mean and median)were lower than those in the non-significant group,and all the differences mentioned above were statistically significant(P＜0.05).The AUC,sensitivity and specificity of DKI combined with IVIM global histogram parameters were the highest,which were 0.816,72.41％and 90.00％,respectively.MD value,D value and D*value were negatively correlated with the efficacy of NAC in breast invasive ductal carcinoma.MK value was positively correlated with NAC efficacy significance.Conclusion DKI combined with IVIM global histogram parameters can effectively predict the efficacy of NAC in patients with breast invasive ductal carcinoma and provide effective value for clinical NAC preoperative efficacy evaluation.

Mouth breathing in children are increasingly concerned by the physicians and the society. Incompetent lip closure can be classified as oral habit and pathological mouth breathing. Pathologic mouth breathing due to hypertrophy of adenoids and tonsils is often the cause of obstructive sleep apnea in children, which may lead to craniofacial deformities and other consequences. At present, there are many problems in the definition, diagnosis and treatment of mouth breathing, which need to be clarified.

The 'Conclusion' section in the Abstract was published incorrectly in the original publication of the article [1] and is corrected with this erratum as below: "Fetal exposure to the Chinese famine may be associated with an increased risk of hypertension in adulthood in women."

Objective:To investigate changes in the circum-maxillary sutures during alternate maxillary expansions and constrictions in a rat model.Methods:Twenty-two male Sprague-Dawley rats (6 weeks old)were used and divided into three groups.In maxillary expansion (ME)group (n=9),an expander was activated for 5 d,and then sacrificed.In alternate maxillary expansions and constrictions (Alt-MEC) group (9 animals),an alternate expansion and constriction protocol (5 d expansion and 5 d constriction for one cycle)was conducted for 2.5 cycles (25 d total),and then sacrificed.The control group com-prised 4 animals with no appliances used,each of two sacrificed on day 5 and day 25 ,respectively.Cir-cum-maxillary sutures (mid-palatal,maxillopalatine,premaxillary,zygomaticotemporal,and frontonasal suture)in each group were characterized histologically.Results:Histological findings of circum-maxil-lary sutures:in control group,the normal sutures were divided into 5 zones,the center was polygon mesenchyme zone,the lateral was mature chondrocyte zone,the next lateral was bone tissue.In ME group,the mid-palatal suture was expanded after ME,the fibre and connective tissue were extracted and invaded into cartilage zone.Osteoblast hyperplasia and new bone formation occurred.The orientation of the new bone trabecula was consistent with force.The osteoclast appeared in some area.Findings of other sutures were similar with those of control group,osteogenesis was active in some area without obvious re-construction in Alt-MEC group,mid-palatal suture and other sutures in some area were widened after Alt-MEC with much more osteoblast hyperplasia and new bone formation.Fibre and connective tissue were extracted,distorted or even broken.Sutures in some areas were narrowed with osteoblast cytopenia and osteoclast hyperplasia.Fibre and connective tissue compressed because of the different force and orienta-tion.Osteoclast count results showed that compared with the control group,the number of the osteoclast was increased only in the palatal suture in ME group (P<0.05 ).Other sutures did not show obvious changes (P>0.05).In Alt-MEC group,the numbers of the osteoclast in circum-maxillary sutures were the most,and had statistical significances (P<0.05 ).Conclusion:These results suggested that cir-cum-maxillary sutures were actively reconstructed after Alt-MEC.while only midpalatal suture had active reaction after ME.

Biological Evolution ; China ; Humans ; Stomatognathic Diseases

Objective: To obtain the data about morphology of upper airway and surrounding tissues of non-snoring males from three age groups. Methods: Through questionnaires and clinic examinations, 83 non-snoring males (20-60 years) were selected from 453 volunteers and involved in the following research. There were 30 volunteers aged from 22 to 29 (mean 23.60?2.58 years), 31 volunteers aged from 36 to 45 (mean 40.10?2.64 years) and 22 volunteers aged from 46 to 57 (mean 49.55?3.45 years). Magnetic resonance imaging (MRI) of upper airway of each volunteer was acquired under strict posture-control conditions. The dimensions and cross-section area of nasopharynx, velopharynx, glossopharynx, hypopharynx and whole upper airway with its surrounding tissues were measured with MRI intrinsic software. Volumes of upper airway and surrounding tissues were also calculated. Results: There were 93 items about morphology of the upper airway and surrounding tissues of non-snoring males from the three age groups.With increase in age, some nasopharynx items showed increase tendency, while little change showed in velopharynx, glossopharynx and hypopharynx. Fat volume, tongue volume, anterior and posterior pharyngeal dimension showed age-related increase tendency, but fat deposition rate slowed down in elder age in non-snoring males, which supplies the reason why non-snoring males avoided becoming sleep apnea patients. Conclusion:We provide age-related reference data of upper airway and its surrounding tissues for further sleep and respiration research.

Obstructive sleep apnea hypopnea syndrome(OSAHS) has been the main research area of the Dental Therapy Center for Sleep Apnea,Peking University School and Hospital of Stomatology.The basic research in the center includs: epidemic survey of OSAHS and snoring in a Beijing population,setting up the cephalometrc and MRI standard of airway and surrounding structures for non-snoring Chinese,aetology exploring OSAHS from views of airway size,craniofacial form,neck circumference and genioglossus muscle activity.Clinically,different dental appliances were developed.The treatment effects of the oral appliances for OSAHS patients were evaluated quantitatively.Two and three dimension changes of the airway and surrounding structures,genioglossus muscle activity,as well as snoring loudness following mandible advancing and opening were studied.Besides,research was expended to OSAHS in children recently.Under the support of National Nature Science Foundation 7 PhD and 3 MS students have graduated.More than 60 papers were published domestically and abroad and two awards were received from the National Ministry of Education and Chinese Medical Association in the past 10 years.This paper is a review of the past and current situation of dental research on OSAHS in China.

Objective:To study the teeth of the ancients in Xia Dynasty,the first dynasty in Chinese history about 4 000 years ago,and acquaint ourselves with their incidences of periodontal disease,and the evolution of oral diseases.Methods:The teeth and jaws excavated in Erlitoou,Henan Province and Youyao,Shanxi Province were observed with clinical methods.The specimens totaled 56 individuals(male 38,and female 18),including 894 teeth,and 86 dental arches.The objects were all permanent teeth.The major observation items were periodontal disease.The prevalence of periodontal disease of the people in Chinese Xia Dynasty were outlined.Results:The prevalence rate of periodontal disease was 19.80% in the 894 teeth,while prevalence rate was about 42.86% among the individuals.The premortal tooth lossrate was 7.45% in the observed teeth.Conclusion:Periodontal disease is an aging-related disease without sex difference and commonly seen in the mandible,which is quite similar to the situation at present.The periodontal disease was the main reason for tooth loss in people of Xia Dynasty.

Objective: To determine the changes of upper airway morphology induced by mandible position from central relation to advancement position in patients with obstructive sleep apnea syndrome. Methods: Nineteen patients (17 males and 2 females) suffering from obstructive sleep apnea syndrome were confirmed with polysomnography. Occlusal wax record was made with mandible in advancement position. Helical computed tomography was performed on each patient in central relation and mandibular advancement position with wax record in situ respectively. On each slice, anteroposterior and transverse diameters were obtained. Airway shape was expressed as the anteroposterior/transverse (AP/T) diameter ratio. Paired samples t test was employed to compare the measurements. Results: With mandibular advancement, average and minimal diameters of glossopharynx and hypopharynx were increased significantly. Compared with it, the change of transverse diameter was more prominent. All segments of upper airway were increased significantly except hypophaynx laterally. Moreover, the change of velopharynx shape was observed on axial planes. Ellipse with transversal long axis became more compressed. Conclusion: Upper airway morphology of all segments was influenced by mandibular advancement whether in the sagittal or transverse plane of space, or airway shape. Not only anatomic connection but also regulation of the nerve system and other still unknown mechanism make contribution to the changes of upper airway morphology in patients with obstructive sleep apnea syndrome. The changes of upper airway morphology above mentioned constitute the rationale of treatment of obstructive sleep apnea syndrome with oral appliances.

OBJECTIVETo study the boundary between orthodontic and surgical treatment in correction of anterior open bite.

METHODS70 cases (18.0 ages in average) treated orthodontically and 14 cases (25.1 ages in average) treated surgically were chosen. 154 hard and soft tissue measurements were analyzed by statistical software.

RESULTSA diagnostic index, L1MP, was gained with simple factorial analysis. L1MP

CONCLUSIONThe diagnostic index and discriminate function were both useful in determining which method to be chosen in treatment of anterior open bite. The discriminate function was tested to be more efficient than the diagnostic index.