Clinical and pathological features and differential diagnosis of fibro-osseous tumors and dysplasias / 中华口腔医学杂志

Fibro-osseous lesions is a class of diseases with obvious similarities in clinical manifestations and pathological features, which has been attracting the attention of clinicians and pathologists. The latest WHO 2022 Classification (5th edition) included six of these diseases (cemento-osseous dysplasia, segmental odontomaxillary dysplasia, fibrous dysplasia, juvenile trabecular ossifying fibroma, psammomatoid ossifying fibroma and familial gigantiform cementoma) in the " fibro-osseous tumours and dysplasias ", and put forward new ideas on the diagnosis and treatment of these diseases. According to the latest WHO 2022 Classification (5th edition), the clinical and pathological features, diagnosis and differential diagnosis of these six diseases were described.

Polarity of ameloblasts and odontoblasts and their related regulators / 华西口腔医学杂志

The polarity of ameloblasts and odontoblasts is crucial for their differentiation and function. Polarity-related molecules play an important role in this process. This review summarizes the process of polarity formation of ameloblasts and odontoblasts and their related regulators.

The role of bone morphogenetic protein signaling pathway in tooth root development / 华西口腔医学杂志

The bone morphogenetic protein (BMP) family is an important factor in the regulation of cell ular life activities and in the development of almost all tissues. BMP-mediated signaling plays an important role in tooth root development, which is a part of tooth development. Epithelial and mesenchymal interactions are involved in tooth root development, but the BMP signaling pathway has a different effect on tooth root development in epithelial and mesenchymal. This review summarizes the advances of BMP signaling in tooth root development.

Effects of lactoferrin on vascular endothelial growth factor and basic fibroblast growth factor expression in human Tca8113 cell line / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of lactoferrin on vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) expression.</p><p><b>METHODS</b>Lactoferrin at concentration of 0.006, 0.013, 0.025, 0.050 g/L and blank control groups were included in this study. The gene and protein expression of VEGF, bFGF were examined by RT-PCR and Western blotting.</p><p><b>RESULTS</b>The RT-PCR and Western blotting assay showed that VEGF mRNA(0.31 +/- 0.08) and protein (0.68 +/- 0.11) in lactoferrin (0.050 g/L) group were significantly lower than in the control group (P < 0.05), and the bFGFmRNA (0.27 +/- 0.10) and protein (0.68 +/- 0.07) in lactoferrin (0.050 g/L) group were also significantly lower than in the control group (P < 0.05).</p><p><b>CONCLUSIONS</b>Lactoferrin could inhibit the expression of VEGF, bFGFmRNA and protein in Tca8113 cells. This effect might be one of the mechanisms for anticancer function of lactoferrin.</p>

The effect of simvastatin on mRNA expression of transforming growth factor-beta1, bone morphogenetic protein-2 and vascular endothelial growth factor in tooth extraction socket / 国际口腔科学杂志·英文版

<p><b>AIM</b>To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-beta1 (TGF-beta1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) in the tooth sockets of rat.</p><p><b>METHODOLOGY</b>Forty-eight male Wistar rats were randomly divided into experimental and control groups (n = 24). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-beta1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation.</p><p><b>RESULTS</b>The fusiform stroma cells in the tooth extraction socket began to express TGF-beta1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-beta1 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group.</p><p><b>CONCLUSION</b>The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket.</p>

Study of methods of decalcification for making united slices of tooth and affiliated periodontic tissues / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the methods of decalcification for making united slices of tooth and affiliated periodontic tissues.</p><p><b>METHODS</b>Twenty-one samples containing dog molars and affiliated periodontic tissues were divided into seven mean groups. The pH value of solution, time of decalcification, weight and volume of samples, and content of decalcified calcium were detected. The slices were observed by HE, specific, and immunohistochemical stain.</p><p><b>RESULTS</b>The velocity of decalcification increased with decrease of solution pH. The weight of samples lightened by 37.61%, the volume reduced by 25.97% on average, and calcium decalcified was 174.49 mg per gram humid samples. The EDTA decalcification was slowest, but it was best. Decalcification was fast in Plank-Rycho solution while the section was worst, and faster in the formyl solution containing aluminium chloride than in EDTA, and the section was better.</p><p><b>CONCLUSIONS</b>The 50% formyl solution containing aluminium chloride is an ideal decalcifying solution.</p>

Inhibition of proliferation of salivary adenoid cystic carcinoma by targeting gene transfer / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression of gene TRAIL driven by human telomerase reverse transcriptase (hTERT) promoter in SACC-83 cell tumor necrosis factor related apoptosis in dncing ligand.</p><p><b>METHODS</b>After pACTERT-TRAIL plasmid transfected was into SACC-83 and HEL cells through liposome, the expression of TRAIL was examined using RT-PCR technique, the cells' survival rate by methyl thiazolyl tetrazolium (MTT) method and apoptosis rate by flow cytometry.</p><p><b>RESULTS</b>Expression of extrinsic TRAIL gene driven by hTERT promoter was detected in SACC-83 cells, and not detected in human embryonic lung fibroblast (HEL) cells. After transfection of pACTERT-TRAIL, the proliferation of SACC-83 cells was significantly inhibited, and its apoptotic rate was promoted, whereas no inhibited effect was observed on HEL cells and its apoptotic rate showed little change.</p><p><b>CONCLUSIONS</b>hTERT promoter can be used to induce tumor-specific expression of TRAIL gene and apoptosis in SACC-83 cells.</p>

Effect of nano-hydroxyapatite to glass ionomer cement / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the mechanical character, microleakage and mineralizing potential of nano-hydroxyapatite (nano-HAP)-added glass ionomer cement(GIC).</p><p><b>METHODS</b>8% nano-HAP were incorporated into GIC as composite, and pure GIC as control. Both types of material were used to make 20 cylinders respectively in order to detect three-point flexural strength and compressive strength. Class V cavities were prepared in 120 molars extracted for orthodontic treatment, then were filled by two kinds of material. The microleakage at the composite-dentine interface was observed with confocal laser scanning microscope (CLSM) after stained with 1% rhodamin-B-isothiocyanate for 24 hours. Class V cavities were prepared in the molars of 4 healthy dogs, filled with composite, and the same molars in the other side were filled with GIC as control. The teeth were extracted to observe the mineralizing property with polarimetric microscope in 8 weeks after filling.</p><p><b>RESULTS</b>Three-point flexural strength and compressive of nano-HAP-added GIC were increased compared with pure GIC (P < 0.001, P < 0.05). The nanoleakages and microleakages appeared at the material-dentine interface in the two groups, but there were more microleakages in control group than in experiment group (P = 0.004). New crystals of hydroxyapatite were formed into a new mineralizing zone at the interface of tooth and nano-HAP-added GIC, while there was no hydroxyapatite crystals formed at the interface of tooth and pure GIC.</p><p><b>CONCLUSION</b>8% nano-HAP-added GIC can tightly fill tooth and have mineralizing potential, and can be used as liner or filling material for prevention.</p>

Effect of TRAIL gene in human squamous cell carcinoma cell line induced by adenovirus / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the apoptotic effect on the squamous cell carcinoma cell line TCa83 induced by recombined adenovirus vector containing TRAIL gene and CMV promoter.</p><p><b>METHODS</b>The TCa83 cell line was firstly infected with different titre of AdCMV-EGFP containing enhanced green fluorescence protein gene (EGFP) as control, and investigated the transducing rate through fluorescence to obtain the definite titre. Then TCa83 cell line was infected with AdCMV-TRAIL in proper titre, and TRAIL gene was detected by means of RT-PCR. After TCa83 cell line was infected with AdCMV-TRAIL and AdCMV-EGFP at day 1, 3, 5, 7, the activity of TCa83 cell line were evaluated by MIT and the apoptosis were detected by flow cytometer.</p><p><b>RESULTS</b>Proper titre was of 1,000 particles/cell, and TCa83 cell line could be infected 100% in this titre. TRAIL gene was detected by RT-PCR after infected with AdCMV-TRAIL. The activity of TCa83 decreased in both groups, but the AdCMV-TRAIL group decreased more sharply than AdCMV-EGFP group (P < 0.001). Both AdCMV-TRAIL and AdCMV-EGFP could lead to apoptosis of TCa83 cells, but the AdCMV-TRAIL, function stronger than AdCMV-EGFP. Especially there was remarkable statistic difference between two groups (P < 0.0001).</p><p><b>CONCLUSION</b>AdCMV-TRAIL could effectively decrease the activity of TCa83 cell line and induce apoptosis.</p>

Targeting transgene effect of adTERT-TRAIL on salivary adenoid cystic carcinoma cell line SACC-83 / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the targeting expression of TRAIL gene driven by human telomerase reverse transcriptase (hTERT) promoter in SACC-83 cell with telomerase activity.</p><p><b>METHODS</b>Adenovirus vector AdTERT-TRAIL was constructed by homologus recombination. After transfecting AdTERT-TRAIL into SACC-83 cell and HEL cell, its effect on these cells in vitro was investigated using RT-PCR technique, MTT method and flow cytometry.</p><p><b>RESULTS</b>After transfection of AdTERT-TRAIL, expression of extrinsic TRAIL gene driven was detected in SACC-83, the proliferation of SACC-83 cell showed significant inhibitory effect (the relative cell viability was 49.70%) and its apoptotic rate was promoted (30.49%), whereas no TRAIL gene was detected in HEL cell, also no inhibitory effect was observed in HEL cell and its apoptotic rate showed little change.</p><p><b>CONCLUSION</b>Adenovirus vector AdTERT-TRAIL was successfully constructed, which can be used to induce expression of TRAIL gene in SACC-83 cell with targeting effect.</p>

Research of the surface oxide film on anodizing Ni-Cr porcelain alloy / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the shape, thickness and oxide percentage of major metal element of oxide film on Ni-Cr porcelain alloy after anodizing pretreatment.</p><p><b>METHODS</b>10 samples were made and divided into 2 groups at random. Then after surface pretreatment, the oxide films of two samples of each group were analyzed using electronic scanning microscope. The rest 3 samples were measured by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES).</p><p><b>RESULTS</b>Lightly selective solution appeared because the different component parts of the alloy have dissimilar electrode, whose dissolve velocity were quite unlike. The sample's metal surface expanded, so the mechanical interlocking of porcelain and metal increased bond strength. The thickness of oxide film was 1.72 times of the control samples. The oxide percentage of major metal elements such as Cr, Ni and Mo were higher, especially Cr. It initially involved the formation of a thin oxide bound to the alloy and second, the ability of the formed oxide to saturate the porcelain, completing the chemical bond of porcelain to metal.</p><p><b>CONCLUSION</b>The method of anodizing Ni-Cr porcelain alloy can easily control the forming of oxide film which was thin and its surface pattern was uniform. It is repeated and a good method of surface pretreatment before firing cycle.</p>

Effect of K2O addition on the crystallization property of dental glass-ceramics / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the effect of K2O addition on the crystallization property of dental glass-ceramics in the Li2O-SiO2-Al2O3-P2O5-ZnO system.</p><p><b>METHODS</b>Different content of K2O was added into Li2O-SiO2-Al2O3-P2O5-ZnO glass system. The heat-treated system of the glass-ceramics was determined by differential thermal analyses (DTA), then the crystallization components and the microstmcture of the glass-ceramics with different content of K2O were investigated from X-ray diffraction (XRD) analyses and scanning electron microscopy (SEM).</p><p><b>RESULTS</b>Addition of K2O helped to reduce the viscosity of the glass system and improved crystallization. More lithium disilicate crystals appeared after heated-treatment of the glass system which contained 5.3 wt% addition of K2O, and the homogeneously lath-shaped crystals were 4 gm in length.</p><p><b>CONCLUSION</b>Certain content of K2O can improve the crystallization property of dental glass-ceramics in the Li2O-SiO2-Al2O3-P2O5-ZnO system.</p>

Effect of simvastatin on residual ridge resorption after tooth extraction / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To observe the effect of simvastatin carried by poly (lactide-co-glycolide) (PLGA) on residual ridge resorption following tooth extraction.</p><p><b>METHODS</b>Sixty male Wistar rats were divided into experimental groups and control groups (30 rats/group). PLGA was immediately implanted with or without simvastatin into extraction sockets of the mandibular incisors. Soft X-ray photography, bone mineral density (BMD) and histopathologic study were conducted at 7, 14, 28, 56, and 84 days after implantation.</p><p><b>RESULTS</b>The relative length values of residual alveolar ridge of the experimental groups were greater than those of the controls at 14, 28, 56, and 84 days after implantation, and there was a significant difference between the experimental and control groups (P < 0.05). The BMD of the specific region was higher in the experimental groups [(7.101 +/- 0.025), (7.178 +/- 0.039), and (7.162 +/- 0.052) g/cm(2)] than that in the control groups [(7.074 +/- 0.014), (7.117 +/- 0.012), and (7.059 +/- 0.037) g/cm(2)] (P < 0.05) after 28, 56, and 84 days. Light microscopy showed that bone formation rate and quality of the experimental group were better than those in the control group at the same time.</p><p><b>CONCLUSIONS</b>Simvastatin carried by PLGA could induce bone formation of tooth socket. Local application of simvastatin would be potential to preserve the length and bone volume of alveolar ridge after tooth extraction.</p>

Cloning and sequence analysis of recombinant fusion gene of Escherichia coli heat-liable enterotoxin B subunit and Actinobacillus actinomycetemcomitans fimbria associative protein / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To clone the recombinant fusion gene of Escherichia coli heat-liable enterotoxin B subunit (Ltb) and Actinobacillus actinomycetemcomitans fimbria associative protein (Fap).</p><p><b>METHODS</b>Two couples of primers were designed for PCR according to the known sequence of ltb and fap. The ltb and fap gene were obtained by amplification PCR technique from plasmid EWD299 of Escherichia coli and Actinobacillus actinomycetemcomitans 310 DNA respectively, and fused them by PCR. The fusion gene ltb-fap were cloning into plasmid pET28a(+). The recombined plasmid pET28a ltb-fap was transformed into Escherichia coli DH5alpha. The recombinant was screened and identified by restriction enzyme and PCR. The cloned gene was sequenced.</p><p><b>RESULTS</b>The ltb-fap about 531bp in size was obtained successfully, and identified by PCR, restrictive enzyme and sequence analysis.</p><p><b>CONCLUSION</b>The vector of pET28a ltb-fap was obtained.</p>

Determination of beta-endorphin in hypothalamus of rat with primary trigeminal neuralgia / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To determine the level and the role of beta-endorphin in hypothalamus of rat with trigeminal neuralgia.</p><p><b>METHODS</b>The animal model of primary trigeminal neuralgia in rat was established, the contents of beta-endorphin were measured by radioimmunoassay techniques.</p><p><b>RESULTS</b>The beta-endorphin of hypothalamus in experimental group was significantly lower than other groups (P < 0.01).</p><p><b>CONCLUSIONS</b>Beta-endorphin may play important roles in primary trigeminal neuralgia.</p>

The effect of overdose fluoride on the proliferation and apoptosis of rat's incisor ameloblast / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To observe the effect of overdose fluoride on the proliferation of rat's incisor ameloblast.</p><p><b>METHODS</b>20 Wistar rats were divided randomly into 2 groups: Group I (Control); Group II 50 mg/L F(-) were given. After 8 weeks treatment, the AgNORs stain and TUNEL technique were applied to analyze the effect of fluoride on the proliferation and apoptosis of ameloblasts.</p><p><b>RESULTS</b>The imagination analysis results showed that proliferation of pre-secretion ameloblasts were inhibited in group II as compared with the control group (P < 0.001). There was significant increase of apoptosis with the trend of migration toward secretion stage.</p><p><b>CONCLUSION</b>The mechanism of fluorosis mottled enamel may be the effect of overdose fluoride with inhibits proliferation and induces apoptosis of ameloblasts resulting in dysfunction of secretion or absorption of enamel matrix proteins.</p>