[Study on promoting bone formation in osteoporotic zebrafish by lithium-doped hydroxyapatite nanowires].

Purpose: To observe the regulatory effect of lithium-doped hydroxyapatite nanowires on bone metabolism in osteoporotic zebrafish induced by dexamethasone.

Methods: Pure hydroxyapatite nanowires(nHA) and hydroxyapatite nanowires doped with 10% lithium ions (Li-nHA) were prepared by using hydrothermal method, and then material characterization was performed. The juvenile zebrafish cultured for 3 days(3dpf) were selected and co-cultured with nHA and Li-nHA extracts up to 7dpf.

[A novel magnetic orthopedic appliance in treatment of preadolescent mild skeletal Class Ⅲ patients].

Purpose: This study was to develop an intraoral Class Ⅲ orthopedic appliance using attractive magnetic forces, and investigate the effect of magnetic orthopedic appliance (MOA-Ⅲ) on skeletal and dental structures in mild skeletal Class Ⅲ children.

Methods: Thirty patients (12 boys and 18 girls) with mild skeletal Class Ⅲ jaw discrepancies were treated with MOA-Ⅲ. The average age was 9 years 3 months at the beginning of the treatment.

[Preparation of lyophilized lentiviral vector of bone morphogenetic protein 2].

Purpose: To construct recombinant lentiviral vectors of bone morphogenetic protein 2(BMP-2) gene and prepare a stable lyophilized state.

Methods: The BMP-2 gene lentiviral vector was constructed by recombinant DNA technology and mixed with different stabilizers in an appropriate proportion and then lyophilized. The optimum stabilizer was selected according to the appearance and virus titer after being lyophilized.

[Study of the mandibular growth phases and quantities in Shanghai adolescents].

Purpose: To study the growth phases and quantities of mandible in Shanghai adolescents.

Methods: The samples included 480 Shanghai adolescents from 8-20 years of age, 240 were male and 240 were female. Both male and female groups were divided into 6 consecutive developmental periods according to cervical vertebral maturation stages.

Sagittal maxillary growth pattern in unilateral cleft lip and palate patients with unrepaired cleft palate.

Objective: The objective of the study was to examine the sagittal maxillary growth pattern during the mixed and permanent dentition in unilateral cleft lip and palate (UCLP) patients with unrepaired cleft palate.

Patients And Methods: A total of 30 nonsyndromic UCLP patients with unrepaired cleft palate were included, 15 of whom were in mixed dentition and 15 in permanent dentition.Cephalograms were analyzed and compared in the patients with UCLP who have operatively undergone repair with both the lip and palate as well as normal subjects.

[Effect of semi-fixed Twin-block appliance on temporomandibular joint remodeling].

Purpose: To evaluate quantitatively the effect of semi-fixed Twin-block appliance on the temporomandibular joint remodeling during the Class II malocclusion treatment.

Methods: Twenty two Class II division 1 patients treated with semi-fixed Twin-block appliance were included. Pre- and post-orthopedic treatment cephalometric data were analyzed with SPSS13.

The effects of maxillary protraction and its long-term stability--a clinical trial in Chinese adolescents.

The purpose of this study was to evaluate the effect of reverse pull headgear (RPHG) in the treatment of Class III malocclusions in the late mixed and early permanent dentition and its long-term stability at the time when facial growth was close to completion. The treatment group comprised 22 subjects (12 males and 10 females, mean age: 11.38 ± 0.

[The effectiveness of asymmetric extraction in treatment of Class II division 1 malocclusions].

Purpose: To analyze hard and soft tissue profile changes before and after asymmetric extraction treatment of Angle Class II division 1 malocclusion.

Methods: Thirty patients of Angle Class II division 1 malocclusions (11 males, 19 females, average age 13.6 years) were divided into two groups according to their extraction approach.

[Identification of cell apoptosis during premaxillary suture expansion in rat].

Purpose: To identify the incidence of cell apoptosis during premaxillary suture expansion.

Methods: Forty SD rats were randomly allotted into experimental and control groups. The experimental animals were subjected to premaxillary suture expansion by a helix spring with (200+/-10)g initial force.

[Establishment of cervical vertebral skeletal maturation of female children in Shanghai].

Purpose: To establish a method for quantitatively evaluating skeletal maturation of cervical vertebrae of female children in Shanghai.

Methods: The samples were selected from lateral cephalometric radiographs of 240 Shanghai girls, aged 8 to 15 years. The parameters were measured to indicate the morphological changes of the third (C3) and fourth (C4) vertebrae in width, height and the depth of the inferior curvature.

The effects of a newly designed twin-slot bracket on severely malpositioned teeth--a typodont experimental study.

The aims of this study were to design a twin-slot bracket featuring two horizontal slots and to examine its efficiency in tooth displacement. Based on the structure of a traditional edgewise bracket, an additional slot was added to a twin-slot bracket and the prototype products were fabricated for the typodont experiments. The orthodontic correction of malpositioned canines was conducted on a typodont to examine the efficiency of the twin-slot bracket in tooth displacement compared with a single-slot edgewise bracket.

[Effect of high pull J hook headgear on root resorption during orthodontic treatment].

Purpose: The purpose of this study was to evaluate the effect of high pull J hook headgear(HPHG) on root resorption of maxillary incisors during orthodontic treatment.

Methods: Sixty female adolescent subjects who had finished orthodontic treatment were selected. They were either Class I or Class II division I cases treated with standard edgewise appliances.

[The effects of combined reverse Nance and TPA on reinforcement of anchorage].

Purpose: To evaluate the effects of combined reverse Nance and TPA on anchorage control.

Methods: 16 female adults with Class II division 1 malocclusion were treated with the combined mechanism of reverse Nance and TPA in an attempt to reinforce molar anchorage. Cephalometric analysis and model measurements were conducted for the assessment of anchorage control.

[A clinical study of twin-wires on anchorage reinforcement].

Objective: This clinical trial was designed to impose a simultaneous placement of large-size stainless steel round wire and small-size NiTi, and to assess its effect on anchorage reinforcement.

Methods: Twin-arch wires were in place for relief of severe crowding. Distalization of canines were well conducted with support of rigid wire, together with a simultaneous repositioning of upper lateral incisors facilitated by resilient wire.

[The feasibility and reliability of Pancherz's analysis in evaluating the treatment effects of bite-jumping on skeletal class II malocclusion].

Objective: This study was designed to conduct an in-depth evaluation on Pancherz's analysis.

Methods: A typical Class II case with bite-jumping therapy was selected for the whole process of Pancherz's Analysis. The skeletal growth modification and dental compensation were examined and portioned for their respective contribution to the correction of excessive overjet and Class II molar relationship.

[An immunohistochemical study on neovascularization in TMJ during mandibular advancement].

Objective: Neovascularization is proved to be closely correlated with ossification. This study was designed to determine the biochemical path through which the new bone formation is enhanced in TMJ during mandibular protrusion.

Methods: SD Rats were fitted with bite-jumping appliances to allow for an adequate advancement of the mandible.

[Study on the relationship between some genetic factors and peak bone mineral density in Beijing young women].

Objective: To evaluate the relationship between the peak bone mineral density (PBMD) and vitamin D receptor (VDR), estrogen receptor (ER) allelic variants in Beijing young women.

Methods: From March, 2000 to July, 2001, one hundred and fifty-nine young healthy women (25 - 37 years old) in Beijing were voluntarily enrolled in the study. (1) BMD were measured by dual energy X-ray absorptiometry (DXEA) at lumbar and hip.