OBJECTIVETo investigate the influences of recasting on the mechanical properties of Au-Pt ceramic alloy.

METHODSAu-Pt ceramic alloy samples were prepared and recast for 3 times without adding any new Au-Pt ceramic alloy. The tensile strength, 0.2% yield strength, percentage of elongation, flexural strength, flexural modulus and Vickers hardness of each specimen were measured.

RESULTSBeing cast for different times, the Au-Pt ceramic alloy showed no significant differences on their tensile strength, 0.2% yield strength, percentage of elongation, flexural strength or Vickers hardness. The flexural modulus of the Au-Pt alloys being cast for 2 or 3 times was significantly higher than that of the alloys being cast for 1 time (P < 0.05). CONCLUSION Au-Pt ceramic alloy can be recast for 3 times at least, without any decrease in the mechanical properties.

Alloys ; Ceramics ; Dental Alloys ; Gold Alloys ; Hardness ; Materials Testing ; Metal Ceramic Alloys ; Tensile Strength

OBJECTIVETo investigate the expression of the peripheral blood retinoid-related orphan receptor gamma t (RORgamma t) and 4-1BB/4-1BBL mRNA in oral lichen planus (OLP) patients.

METHODSThe expression levels of peripheral blood' RORyt mRNA and 4-1BB/4-1BBL mRNA of 30 samples of OLP patients and 30 cases of healthy human were detected using real-time fluorescent quantitative-polymerase chain reaction (FQ-PCR) technology.

RESULTSIn the OLP group, the expression level of RORgamma t, 4-1BB, 4-1BBL mRNA were higher than those in the control group (P < 0.05). After the conversion of the 2-delta delta CT, the expression levels of three kinds of mRNA in the OLP group were 3.087, 3.320 and 4.005 times of the control group respectively. In the OLP group, the expression levels of RORgamma t mRNA and 4-1BB mRNA had no obvious correlation (P > 0.05), the expression levels of 4-1BB and 4-1BBL mRNA had a positive correlation (r = 0.455 0, P < 0.05).

CONCLUSIONThe abnormal expression of RORyt, 4-1BB and 4-1BBL mRNA may play certain roles in the pathogenesis of OLP.

Humans ; Lichen Planus, Oral ; Male ; RNA, Messenger ; Retinoids

OBJECTIVETo investigate the influence of celecoxib, cycloxygenase-2 (COX-2) selective inhibitor, upon the proliferation of KB/VCR cells, and analyze the effect of celecoxib on the expression of P-glycoprotein (P-gp).

METHODSMTT method was employed to study the inhibitory effect of celecoxib on KB/VCR cells, which were divided into vincristine (VCR) group, Celecoxib group, Celecoxib + VCR group, Celecoxib + VCR + prostaglandin E2 (PGE2) group. Western blot was employed to detect the expression of P-gp, Bcl-2 and Bcl-X(L). Flow cytometry was used to evaluate the apoptosis of KB/VCR cells. All of the data were statistically analyzed using SPSS 13.0 software package.

RESULTSThe growth inhibition rate of KB/VCR cells in Celecoxib+VCR group was significantly higher than that in Celecoxib group, VCR group and Celecoxib + VCR + PGE2 group (P < 0.01). The expression of P-gp in Celecoxib + VCR group and Celecoxib group were markedly lower, compared with those in VCR group and Celecoxib + VCR + PGE2 group (P < 0.01). The expression of Bcl-2, Bcl-XL in Celecoxib+VCR group, Celecoxib+VCR+PGE2 group and Celecoxib group were significantly lower than those in VCR group (P < 0.01). The apoptosis rate of Celecoxib + VCR group, Celecoxib + VCR + PGE2 group were significantly higher than those in VCR group and Celecoxib group (P < 0.01). The apoptosis rate of Celecoxib+VCR+PGE2 group were significantly lower than those in Celecoxib+VCR group (P < 0.01).

CONCLUSIONCelecoxib could enhance the toxicity of VCR against KB/VCR cells. The mechanism probably correlates with the downregulation of celecoxib on the expression of P-gp and the increase of apoptosis.

ATP-Binding Cassette, Sub-Family B, Member 1 ; Apoptosis ; Celecoxib ; Cell Line, Tumor ; Drug Resistance, Neoplasm ; Humans ; Pyrazoles ; Sulfonamides ; Vincristine

OBJECTIVETo investigate the association between rs142167, rs7216231 single nucleotide polymorphism (SNP) in Wnt3 and nonsyndromic cleft lip and palate (NSCL/P) in Hui and Han population of Ningxia Autonomous Region.

METHODSThe study consisted of 371 NSCL/P patients from Ningxia Hui and Han population (Han population 166, Hui population 205), their parents (196 fathers, 224 mothers, 150 trios) and 258 normal controls (Han population 190, Hui population 68). Polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) was used to identify rs142167, rs7216231 genotypes of the samples. The data was analyzed by case-control analysis, transmission disequilibrium test (TDT) and family based associated test (FBAT).

RESULTSCase-control study showed that no differences in cleft lip, cleft palate, cleft lip and palate, and the total case group compared with the control group at rs142167 and rs7216231 (P > 0.05) in Hui and Han population and in stratified comparison. TDT test showed that rs142167 and rs7216231's allele had not over-transmitted (P > 0.05) in NSCL/P. FBAT test showed that G-G specific haplotypes showed statistically significant (P < 0.05).

CONCLUSIONWnt3 gene polymorphism is not relevant with NSCL/ P in Ningxia Hui and Han population.

Brain ; abnormalities ; Case-Control Studies ; Cleft Lip ; Cleft Palate ; Genotype ; Humans ; Polymorphism, Genetic ; Polymorphism, Single Nucleotide

OBJECTIVETo investigate the influence of digit-sucking habit on palatal features in pre-school children by using a laser scanning system.

METHODSForty pre-school children were chosen according to the results of questionnaires, among which 20 with digit-sucking habit(digit-sucking group) and 20 without any oral habits(control group). Impression of the upper jaw was taken from each child. After laser scanning the plaster casts, and three-dimensional reconstruction by the computer, parameters of anterior and posterior palatal length, width and height were measured, ratios of height/width, length/width and width ratio of anterior and posterior palatal were analyzed. The differences of palatal features between two groups were analyzed by t test.

RESULTSThere was statistical significance between digit-sucking group and control group in posterior palatal width, anterior palatal length and anterior palatal height. The ratios of height/width and length/width in both posterior and anterior areas were statistically significant (P < 0.05). Compared to the control group, the results indicated that palatal features were relatively deeper, narrower and more protrusive in digit-sucking group.

CONCLUSIONThe digit-sucking habit may have some deleterious impacts on the palatal features in pre-school children with primary dentition. And it is practical to measure the spacial palatal features by using laser scanning system to some extent.

Child ; Child, Preschool ; Fingersucking ; Habits ; Humans ; Lasers ; Malocclusion ; Maxilla ; Tooth, Deciduous

OBJECTIVETo promote the diagnostic accuracy of salivary Warthin's tumor by summarizing the ultrasonographic features of salivary Warthin's tumor.

METHODSSixty-nine lesions (58 patients with salivary Warthin's tumor) were retrospectively studied by ultrasonography and confirmed by histopathology.

RESULTSThe ultrasonographic manifestations of salivary Warthin's tumor demonstrated in three patterns.Type I: Solid mass(34 lesions, 49.3%), the mass was solid, grid-shaped echo inside. The mass was pathologically composed of such various tissues as epithelial cells, lymphatic organization, fibrous tissue which were compactly and evenly arranged, and little mucous formed the cyst cavity in which there projected epithelial papilla. Type II: Cystic-solid mixed mass(30 lesions, 43.5%), there was no flake-like echo, cystic-solid boundary was clear. Histopathological study revealed glandular epithelium made up irregular catheter and cyst cavity with yellowish mucous, glue-frozen-like stuff or brown colloidal substances. Type III: Cystic mass (5 lesions, 7.2%), the mass manifested separated cystic echo crumbs. The histopathological study showed salivary Warthin's tumor with infarctions and infections. The coincidence of ultrasound and histopathology diagnose was 79.7%.

CONCLUSIONThe ultrasonographic features of salivary Warthin's tumor are mainly based on the organization of histopathological study. The grasp of various ultrasonographic imagings and pathological changes is beneficial for increasing the accuracy rate of diagnosis higher.

Adenolymphoma ; Epithelial Cells ; Epithelium ; Humans ; Retrospective Studies

OBJECTIVETo evaluate the most acceptable lower anterior face height of male and female by orthodontic treatment seeking people.

METHODSTwo hundred and thirty-two Chinese orthodontic seeking people of Guanghua Hospital of Stomatology of Sun Yat-sen University were randomly selected in this survey. An electronic questionnaire was designed with a set of male and female young Chinese adult images with changes of the lower anterior face height (while the middle anterior face height remains the same). They were asked about the lowest, highest and optimal proportion (or so-called lower, higher and optimum limits respectively) between the lower anterior face height and the middle anterior face height (LAFH/MAFH) they could accept. All the findings of the proportion were analyzed by a statistic system.

RESULTSThe lower limits' median value in regard to the LAFH/MAFH of male model and female model images was 0.8, this limit value for the male model's was greater than the female model's (P = 0.039); the higher limits' median value was 1.1, this limit value for the male model's was less than the female model's (P < 0.001); the optimum limits' median value was 0.9, this limit value for the male model's was greater than the female model's (P < 0.001).

CONCLUSIONThe result of this study shows all lower, higher and optimal limits accepted by the orthodontic treatment seeking people in regard to the proportion between the lower and middle height of anterior faces. This result will facilitate the understanding of aesthetic judgments of orthodontic patients on profile lower anterior facial height for orthodontist in treatments.

Adolescent ; Adult ; Cephalometry ; Esthetics, Dental ; Face ; Female ; Humans ; Male ; Vertical Dimension

OBJECTIVETo evaluate the anesthetic effects and safety of Gow-Gates technique of inferior alveolar nerve block in impacted mandibular third molar extraction.

METHODSA split-mouth study was designed. The bilateral impacted mandibular third molar of 32 participants were divided into Gow-Gates technique of inferior alveolar nerve block (Gow-Gates group) and conventional technique of inferior alveolar nerve block (conventional group) randomly with third molar extracted. The anesthetic effects and adverse events were recorded.

RESULTSAll the participants completed the research. The anesthetic success rate was 96.9% in Gow-Gates group and 90.6% in conventional group with no statistical difference ( P= 0.317); but when comparing the anesthesia grade, Gow-Gates group had a 96.9% of grade A and B, and conventional group had a rate of 78.1% (P = 0.034). And the Gow-Gates group had a much lower withdrawn bleeding than conventional group (P = 0.025). Two groups had no hematoma.

CONCLUSIONGow-Gates technique had a reliable anesthesia effects and safety in impacted mandibular third molar extraction and could be chosen as a candidate for the conventional inferior alveolar nerve block.

Anesthesia, Dental ; Anesthetics ; Female ; Humans ; Injections ; Mandible ; Mandibular Nerve ; Molar ; Molar, Third ; Nerve Block ; Tooth Extraction

OBJECTIVETo compare the efficacy of hydroxyapatite (HA), calcium hydroxide (CH) and Vitapex on root formation of immature teeth of dogs.

METHODSSixteen roots of permanent incisors in two dogs (about five to six months old) were used. After the pulpectomy, roots were randomly divided into four groups. Group A, B and C were experimental groups and filled with HA, CH and Vitapex, respectively. Group D was control group and filled with AH plus. The changes of root length and apical areas were measured by cone beam CT(CBCT), meanwhile, paraffin sections with hematine-eosin (HE) staining were used to observe the shape of root tips; frozen sections with alkaline phosphatase (ALP) staining were used to observe the osteoplastic activity of cells.

RESULTS1) CBCT showed that four weeks later, all roots in every groups became longer (P < 0.05), and the apical areas in three experimental groups decreased (P < 0.05). However, eight weeks later, high density image could be detected in every root. 2) Histological examination showed that there was no inflammation in every group, and after four weeks, none of apicals were closed, but partial cementum and peridental membrane had extended into canals. After eight weeks, a complete cementum barrier and an intensive distribution of positive cells of ALP staining could be seen in group A, however, some spaces could be seen in the cementum barrier of group B and C, which were filled with periodontal membranes, and the positive cells of ALP staining were dispersed. Moreover, scattered cementum, cementoid and abundance fiber or blood vessels could be seen in group D, in which ALP staining was negative.

CONCLUSIONThe root formation of immature teeth can go on after pulpectomy when there is no inflammation, the tissue source is probably the periodontal membrane, and HA which can induce root formation faster is a better material in the apexification.

Animals ; Apexification ; Calcium Hydroxide ; Dental Cementum ; Dogs ; Periodontal Ligament ; Root Canal Filling Materials ; Silicones ; Tooth Root

OBJECTIVETo provide basis for effects of an early psychological intervention on parents of children with cleft lip/palate, and investigate the effects of an early psychological intervention to them.

METHODSOne self-administered questionnaire (SCL-90) was applied in 102 parents of children with cleft lip/palate, compared to 126 parents of healthy individuals on the day of admission. They were given the psychological intervention during hospitalization and 3 months after discharge. The questionnaire (SCL-90) was again applied to them on the day of discharge and 3 months after discharge.

RESULTSUsing the questionnaire (SCL-90), the answer scores of somatization, obsessive-compulsive, depression and anxiety etc. were significantly higher than those of the control group (P < 0.05). There were no statistical differences during 3 subgroups in the case group (P > 0.05). There were no statistical differences on the day of admission and on the day of discharge (P > 0.05), but there were statistical difference on the day of admission and 3 months after discharge (P < 0.05).

CONCLUSIONIn this study, the psychosomatic states of parents of children with cleft lip/palate is poor. It's important and greatly significant that we conduct early psychological intervention to parents of children with cleft lip/palate and to the children's psychosomatic health.

Child ; Cleft Lip ; Cleft Palate ; Female ; Humans ; Male ; Parents