Five-year investigation of a large orthodontic patient population at a dental hospital in South Korea / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to investigate the characteristics of orthodontic patients at Yonsei Dental Hospital from 2008 to 2012. METHODS: We evaluated Angle's classification from molar relationships, classification of skeletal malocclusion from the A point-nasion-B point angle, facial asymmetry, and temporomandibular joint disorders (TMDs) from the records of 7,476 patients who received an orthodontic diagnosis. The orthognathic surgery rate, extraction rate, and extraction sites were determined from the records of 4,861 treated patients. RESULTS: The patient number increased until 2010 and gradually decreased thereafter. Most patients were aged 19-39 years, with a gradual increase in patients aged ≥ 40 years. Angle's Class I, Class II divisions 1 and 2, and Class III malocclusions were observed in 27.7%, 25.6%, 10.6%, and 36.1% patients, respectively, with a gradual decrease in the frequency of Class I malocclusion. The proportion of patients with skeletal Class I, Class II, and Class III malocclusions was 34.3%, 34.3%, and 31.4%, respectively, while the prevalence of facial asymmetry and TMDs was 11.0% and 24.9%, respectively. The orthognathic surgery rate was 18.5%, with 70% surgical patients exhibiting skeletal Class III malocclusion. The overall extraction rate among nonsurgical patients was 35.4%, and the maxillary and mandibular first premolars were the most commonly extracted teeth. CONCLUSIONS: The most noticeable changes over time included a decrease in the patient number after 2010, an increase in the average patient age, and a decrease in the frequency of Angle's Class I malocclusion. Our results suggest that periodic characterization is necessary to meet the changing demands of orthodontic patients.

pSVPoMcat modifying Schwann cell to protect injured spinal neurons in rats / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the protective effect of pSVPoMcat (myelin basic protein microgene) modifying Schwann cell on injured spinal neurons.</p><p><b>METHODS</b>A model of rat spinal cord injured by hemisection was used. One hundred and twenty healthy SD rats of both sexes weighing 250-300 g were divided into three groups: Group A (n=40, treated with implantation of pSVPoMcat modifying Schwann cell), Group B (n= 40, treated with implantation of Schwann cell only) and Group C (n=400, treated with sham operation as the control). One week after operation the rat functional recovery was observed dynamically by using combined behavioral score (CBS) and cortical somatasensory evoked potentials, the spinal cord sections were stained by Nissl, acid phosphatase enzyme histochemistry and cell apoptosis was examined by methye green, terminal deoxynucleotidyl and the dUTP Nick end labeling technique. Quantitative analysis was done by computer image analysis system.</p><p><b>RESULTS</b>In Group A the injured neurons recovered well morphologically. The imaging analysis showed a result of Group A<Group B<Group C in the size of the neurons (P<0.01). The percentage of ACP (acid phosphatase) stained area and the rate of apoptosis sequence were groups A<B<C. The change of tendency was correlated to their function recovery according to CBS.</p><p><b>CONCLUSIONS</b>pSVPoMcat modifying Schwann cell implantation has protective effect on injured spinal neurons and promotes recovery of injured spinal cord function in rats.</p>

Repair effect of Schwann cells modified by microgene pSVPoMcat on injured spinal cord in rats / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To observe the repair effect of Schwann cells (SCs) modified by microgene pSVPoMcat on injured spinal cord in rats.</p><p><b>METHODS</b>Semi-transection injury at the level of T(8) of spinal cord was made with cutting method on 120 Sprague Dawley (SD) rats. Then 40 rats implanted with SCs modified by microgene pSVPoMcat were taken as Group A, 40 rats implanted with simple SCs as Group B and the other 40 rats were taken as the control group (Group C). The functional recovery of the rats was observed through combined behavioral score (CBS) and cortical somatosensory evoked potential (CSEP), and the expression of the glial fibrillary acidic protein (GFAP) was measured with in situ hybridization and immunocytochemistry. At 3 months after operation, the rats were examined with magnetic resonance image (MRI), and the neurofilaments (NF) of the axons were stained with immunohistochemical method.</p><p><b>RESULTS</b>GFAP expression in Group A was significantly lower than that of the other 2 groups. MRI showed that the spinal signals in the injured area recovered fundamentally in Group A, didn't recover in Group B and malacia focus was found in Group C, which was same as the results of NF staining. Wave amplitudes in incubation periods in Group A and Group B tended to recover. It recovered to the normal level in Group A, which was similar to the results of CBS.</p><p><b>CONCLUSIONS</b>SCs modified by microgene pSVPoMcat can inhibit GFAP expression, improve the growth of the axons and the functional recovery of neurons after spinal cord injury.</p>