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Table of Content
20 April 2002, Volume 20 Issue 02
  • An Experimental Study on the Inhibitory Effects of Anti-human Vascular Endothelial Growth Factors on the Growth of Buccal Mucosa Carcinoma
    Fang Silian, Wang Dazhang,Yang Xichuan, Li Hong, et al
    West China Journal of Stomatology. 2002, 20(02):  89-91. 
    Abstract ( 835 )   HTML ( 26 )   PDF(pc) (148KB) ( 524 )   Save
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    Objective:The purpose of this study was to apply the anti-human VEGF monoclonal antibody E11, which was generated against a synthetic peptide from the NH2of the human VEGF (residues 1-26), to againstVEGF in buccal carcinoma, and to ex- amine the inhibition effect of the antibody on the carcinoma growth.Methods:E11was hypodermic and celiac injected, with 200 Lg each from the first to the 15th day, into BALBPc nuPnu mice, whichwere transplanted with human buccal carcinoma. The sa- line was injected as the negative control. Mice were killed on the 18th day. The tumor weight was determined and the inhibition rate was calculated.Results:The growth of BCaCD885 carcinomawas dramatically inhibited in the E11group. There was a signifi- cant difference in tumorweight between the saline group and the E11groups during the observation period. The tumor growth inhi- bition rate in the mice hypodermically injected with E11reached 69.9%.Conclusion:The anti-human VEGFmonoclonal antibody E11significantly inhibits tumor growth by blocking the action of VEGF, and without obvious side effects, therefore the anti-human VEGF monoclonal antibody could be applied clinically in the anti-angiogenic treatment of solid tumors.

    Expression of mdr1 in Oral Squamous Cell Carcinoma
    Zhang Jie, Zhang Jianguo, Zhao Fuyun
    West China Journal of Stomatology. 2002, 20(02):  92-94. 
    Abstract ( 789 )   HTML ( 26 )   PDF(pc) (145KB) ( 464 )   Save
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    Objective:The expression of mdr1 is associated with chemotherapeutic efficacy of cancer, some patientswith oral cancer are resistant to chemotherapy, the authors therefore investigated the mRNA expression level of mdr1 in oral squamous carcinoma. Methods:Totally 26 sampleswere investigated in this study, and the total RNAof oral squamous cell carcinoma each sample were extracted and hybridized with probe pchp-1 .The level of mdr1 were compared with the cell line Tca8113, Tca8113P100 and Tca8113P200, whichwere sensitive, resistant to VCR100 nmol and 200 nmol respectively.Results:The results showed that in the 26 patients, the mdr1 level ranged from0.3@105to 5@105. Among the 26 patients, 9 were drug-sensitive; 14 were lowdrug-re- sistant; and the other 3 were highly drug-resistant. The rate of drug resistance was 65%. The expression of mdr1 was not related with the pathologic differentiation and TNM classification.Conclusion:The multi-drug resistance of the malignant tumor to chemo- therapy is the important factor of unsatisfied effect of chemotherapy, and this paper systemically studied on the mdr1 expression of the oral squamous cell carcinoma, and the relation with pathologic differentiation and TNM classification. The result is important for choosing the chemotherapeutic regime for patients.

    Roles of Proliferation and Apoptosis of Chondrocytes in Inflammatory Lesions Mediated by Recombinant Human Interleukin-1B on Condylar Cartilage of Temporomandibular Joint
    Li Song, Yang Chun, Luo Yingwei, et al
    West China Journal of Stomatology. 2002, 20(02):  95-97. 
    Abstract ( 725 )   HTML ( 20 )   PDF(pc) (190KB) ( 396 )   Save
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    Objective:The purpose of this studywas to evaluate the role of cell proliferation and apoptosis in the inflammatory lesionme- diated by recombinanthuman interleukin-1Bon condylar cartilage of temporomandibular joint.Methods:The model of inflammatory lesion of temporomandibular jointin SD ratswas established by intraarticularinjectionwith recombinanthuman interleukin-1B. The expressions of proliferating cell nuclear antigen (PCNA) and apoptosis in cartilage were examined by immunohistochemical staining and Tdt-mediated dUTP nick end labelling (TUNEL) during series time of after injection of recombinant human interleukin-1B. Results:The immunostaiing results showed thatPCNAproteinwas expressed in proliferative zone of condylar cartilage, the positive index of PCNA decreased in proliferative zone after injection of recombinant human interleukin-1B1~30 days, and more obviously in 1~7 days. Apoptotic chondrocytes were mainly located in proliferative zone and the prehypertrophic zones, and the apoptotic chondrocytes increased in proliferative and prehypertrophic zones of condylar cartilage (P<0105).Conclusion:These results sug- gest that suppression of proliferating cell nuclear antigen and high apoptosis of chondrocytes may play an important role in the in- flammatory lesion or in the destructive process of temporomandibular joint osteoarthritis.

    Effects of a New Silicone Rubber Impression Material on the Fit of Non-precious Alloy Crowns
    Fan Xinping, Zhao Yunfeng, Wei Wei et al
    West China Journal of Stomatology. 2002, 20(02):  98-100. 
    Abstract ( 890 )   HTML ( 20 )   PDF(pc) (152KB) ( 564 )   Save
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    Objective:The purpose of this study was to investigate effects of a new silicone rubber impression material on the fit of SDA-Ⅱalloy crowns.Methods:Totally twelve tooth-preparation analogswere divided into sixgroups. Two kinds of impressionma- terial (Jeltrate Exaflex) and a new silicone robber impression material were used. A total of 12 impressionswere obtained from 12 master models with the 1-step technique directly. And then the fitness of SDA-Ⅱalloy crownswas examined. The measurements were recorded at 3 points for a marginal fit and inner fit evaluation respectively.Results:There was no statistically significant dif- ference in marginal open and inner fit of SDA-Ⅱalloy crowns between both impression materials (P>0105).Conclusion:The SDA-Ⅱalloy crown fabricated by using the new impression material yields acceptable marginal fit and inner fit.

    A Conditional Study of Analyzing Oral Bacterial End Products with Gradient Reversed-phase High Performance Liquid Chromatography
    Zhang Ping, Zhu Zhu, Xiao Xiaorong et al
    West China Journal of Stomatology. 2002, 20(02):  101-103. 
    Abstract ( 893 )   HTML ( 21 )   PDF(pc) (149KB) ( 387 )   Save
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    Objective:The purpose of this studywas to optimize the conditions of analyzing oral bacterial end products by using reversed- phase high performance liquid chromatography (RP-HPLC).Methods:Different culture fluid, temperature, solution pH, extract, deposition were used to investigate oral bacterial end productswithHPLC. The optimal chromatographic parameterswere: flowrate of 110 mlPmin and 210 mlPmin, detection UV at 217 nm, 5% methanol in phosphate buffer solution (pH218) as mobile phase, linear gradientwashwith 5% to 40% methanol for10 min, at ambient temperature.Results:Oral bacteria cultured in brain heart infusion broth (BHI); their supernatantwas adjusted to pH117, and then extracted by ether. With the above conditions, an opti- mal result can be obtained by analyzing using HPLC.Conclusion:The results of this paper will facilitate the identification and classification of oral bacteria by analyzing oral bacterial end products.

    Roles of Fibronectin in Reparative Dentinogenesis: An Immunohistochemical Study
    Chen Zhi, FanMingwen, L?Ping, et al
    West China Journal of Stomatology. 2002, 20(02):  104-106. 
    Abstract ( 754 )   HTML ( 20 )   PDF(pc) (166KB) ( 699 )   Save
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    Objective: The aim of this studywas to investigate roles of fibronectin in dental pulp injury and repair.Methods: The cavity was prepared in the mesial surface of the firstmolars ofWistar rats. The ratswere sacrificed in 3, 15, and 30 days post-operation. After histological process, the paraffin sectionswere reactedwithmonoclonal antibodies against ratfibronectin usingSABCmethod. Results: Immunohistochemical stain demonstrated that the positive staining of fibronectin presented in different stages of dental pulp repair. In the group of 3 days, the weak stainingwas located in odontoblasts. After15 days, odontoblast-like cells and dental pulp cells were stained positively. 30 days after operation, the stronger stainingwas observed in odontoblast-like cells and pulp fi- broblasts. Positive staining was seen in reparative dentin, particularly along the interface of reparative dentin and dental pulp. Conclusion: These results demonstrated that fibronectin might play a role of mediation during the reparative dentinogenesis.

    A Preliminary Study on Polyhydroxybutyrate Membrane for Guided Tissue Regeneration
    Bao Chongyun, Chen Zhiqing, Ou Guomin, et al
    West China Journal of Stomatology. 2002, 20(02):  107-109. 
    Abstract ( 842 )   HTML ( 20 )   PDF(pc) (223KB) ( 547 )   Save
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    Objective:An ideal guided tissue regeneration membrane (GTRm) should possesses good biocompatibility, adequate me- chanical strength and biodegradability. Polyhydroxybutyrate(PHB) is a biodegradable hermopolymer that composed by microorgan- isms. The objective of this study was to explore the possibility of using PHB membrane for guided tissue regeneration.Methods: PHB membrane was prepared by solvent-casting techniques and its physical and chemical properties were examined. Biodegrad- ability and biocompatibility of PHB membranes were inspected by embedding PHB membranes into dogs for 1 week, 1, 2, and 3 months. The scanning electronmicroscopy (SEM) was used to evaluated biodegradability of PHB membranes, and biocompatibility of PHB membranes was tested by detecting local tissue response with light microscopy (LM).Results: (1)The extension strength and the elongation of fracture of PHB membraneswere 2812 MPa and 113% respectively. (2)The morphologic observation of PHB membranes at different terms showed that the surface turned rough because PHB membranes had been biodegraded gradually. (3) The capsule surrounding PHB membrane wasmainly consisted of fibrocytes and few lymphocytes. The longerwe observed, the thi- nner the capsule enveloping PHB membrane formed.Conclusion: PHB membranes possess satisfactory mechanical properties, bio- compatibility and, can be biodegraded slowly in vivo. PHB membranes could be therefore applied as a biological material for GTR.

    The Expression of Basic Fibroblast Growth Factors and Their Receptors in Human Dental Pulps
    Zhang Ying, WangMeixia, Zhang Yu, et al
    West China Journal of Stomatology. 2002, 20(02):  110-111. 
    Abstract ( 699 )   HTML ( 20 )   PDF(pc) (164KB) ( 389 )   Save
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    Objective:The aim of this study was to observe the expression and the effect of basic fibroblast growth factors (bFGFs) and their receptors (bFGFRs) in human dental pulps.Methods:By collecting sound human third molars and premolars, the paraffin sample of tooth slice were prepared with ordinary methods. The bFGFs and bFGFRof human dental pulpswere examined by using SABC immunohistochemical technique.Results:Strong specific staining for bFGF was observed in the odontoblasts of healthy te- eth, and positive stainingwas found in other pulp cells and vascular endothelial cells. The faint signal of bFGFRwas detected only in the odontoblasts, and negative in other pulp cells.Conclusion:The expression of basic fibroblast growth factor (bFGF) and its receptor (bFGFR) in human dental pulp suggests that bFGF and its receptormay play an important role in the reactionary and re- pairable dentinnogenesis.

    Clinical Classification and Therapy of Articulation Disorders
    West China Journal of Stomatology. 2002, 20(02):  112-114. 
    Abstract ( 714 )   HTML ( 24 )   PDF(pc) (145KB) ( 942 )   Save
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    Objective:The aim of this studywas to investigate the clinical classification and seek for an effective therapy method for artic- ulation disorders.Methods:229 patients (130 male, 99 female, ranged from 4 to 36 years) were investigated in this study. Sub- jects were classified into two groups: velopharyngeal insufficiency and no velopharyngeal insufficiency. Patients of each groupwere given the special therapy respectively.Results:134 patients who were treated didn.t showed difference in speech intelligibility, comparing with normal persons; and only one patient had two ormore types articulation disorders.Conclusion:The therapy of ar- ticulation disorders is not uniform, but successful therapy might contribute to the accurate diagnosis and the correct selection of treatment methods.

    Fixed-removable Dentures Retained with Magnetic Attachments
    Zhao Yimin, Lin Lihong, Dong Jie, et al
    West China Journal of Stomatology. 2002, 20(02):  115-117. 
    Abstract ( 975 )   HTML ( 21 )   PDF(pc) (224KB) ( 813 )   Save
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    Objective:The aim of this study is to retrospect the retention and stability for fixed-removable denture with magnetic attach- ments.Methods: Magfit EX 600W magnetic attachments were used as the extra-coronal retainer on abutments, and the guide plane and Key-key way were applied as the stable structure for dentures. The fixed-removable dentures were fabricated in casting framework way. The applied effect of the fixed-removable denture was followed up.Results: The extensive defects of dentition of 15 cases were restored successfully with the fixed-removable dentures. The follow-up investigation showed that the compact, aes- thetic and comfortable fixed-removable denture could supply reliable retention, stability and highly masticatory efficiency.Conclu- sion: Magnetic attachments can be used in fixed-removable dentures and help to obtain reliable retention and stability of dentures.

    Use of Patient-controlled Sedation During the Extraction of Impacted Teeth
    Wu Junlou, Mao Zuyi, Li Ningyi et al
    West China Journal of Stomatology. 2002, 20(02):  118-120. 
    Abstract ( 888 )   HTML ( 20 )   PDF(pc) (86KB) ( 455 )   Save
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    Objective:The purpose of this study was to evaluate the clinical effects of patient-controlled sedation during the extraction of impacted tooth.Methods:The patient-controlled sedation with propofol was compared to non-sedation, in a randomized crossover study of 22 outpatients undergoing two-stage bilateral extraction of impacted third molar teeth under local anesthesiawith 2% Lido- caine. Cardiovascular and respiratory stability and the effects of sedationwere observed; postoperative memory was measured with delayed free recall.Results:The blood pressure and heart rates were stable and showed no difference in Group P and Group L(P >0105). Haemoglobin oxygen saturationwasmaintained at a level of 97% orhigherfor all patients. Sedationwas no deeperthan 3 Ramsy scores. Intra-operative patient cooperation, postoperative patient satisfaction and surgeon satisfaction in group P were higher than those in group L(P<0105).Conclusion:Patient-controlled sedation may be a safe and effective intraoperative seda- tion.

    Effects of Orthodontic Appliances on Oral Micro-ecological Environment
    Lin Li, Liang Jiaxing,Luo Songjiao et al
    West China Journal of Stomatology. 2002, 20(02):  121-124. 
    Abstract ( 871 )   HTML ( 20 )   PDF(pc) (161KB) ( 580 )   Save
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    Objective:This study aimed atinvestigating effects of fixed appliances on the oral micro-ecological environment and establish- ing further the potential relationship between fixed appliances and the occurrence of caries and gingivitis during orthodontic treat- ment.Methods:50 orthodontic subjects were divided into two equal experimental groups according to the frequency and period of tooth-brushing. 10 non-treated volunteers served as the control group. Dental plaque samples were taken from the testing site at four different times, before the treatment, and 2 weeks, 4 weeks, and 8 weeks after the placement of the orthodontic brackets and bands. Congo red negative stained smearwas introduced to determine the composition of the bacteria from dental plaque.Results: After the insertion of brackets, the dental plaque from the distobuccal aspects of the second mandibular bicuspids showed signifi- cant shifts on the composition of bacteria along with time, the percentage of bacilli increased; contrarily, a decrease in cocci was noted. The frequency and period of tooth-brushing influenced the transformation of composition of bacteria distinctly. Whereas the dental plaque sample from the molar margin did not show significance changes in composition of bacteria after banding despite of the varied oral hygiene measures.Conclusion:The insertion of brackets in the second mandibular bicuspid caused the change of microecological environment by/shifting0the dental plaque to a more disease-inducing population and became the potential factor of the gingivitis and caries during orthodontic treatment, but reinforced oral hygiene measure would be helpful in reducing the risk of caries and gingivitis in bicuspid.

    A Two-year Clinical Trial of Atraumatic Restorative Treatment in Primary Teeth
    Li Xue, Hu Deyu, Wan Huchun, et al
    West China Journal of Stomatology. 2002, 20(02):  125-127. 
    Abstract ( 763 )   HTML ( 20 )   PDF(pc) (85KB) ( 515 )   Save
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    Objective:The purpose of this clinical trialwas to investigate the effects of atraumatic restorative treatment(ART) underfield conditions, compare it to another treatmentwith amalgam, and survey the acceptability of this approach by patients.Methods:154 teeth were treated using ART, while other 151 teeth were treated using amalgam, and the therapeutic effects of each patient was evaluated after half of year, 1 year and 2 years.Results:Most of the children did not report discomfort during treatment, and 9312% would like to selectARTrather than other treatments. The one-year and two-year success rates of ARTwere 8417% and 6911%. Comparing with those of amalgam restorations (7712% and 6712%), there was no statistical difference (P>0105). However, the two-year recurrent rate of secondary caries treated with ART approach (912%) was obviously lower than that with amalgam treatment (2115%)(P<0105).Conclusion:ARTmay be an appropriate and effective method for the treatment of pri- mary teeth.

    A Study on the Relationship between Mesiodens and Diastema of Maxillary Incisors
    Gu Xiangsheng, Li Ruyao, Wang Dawei, et al
    West China Journal of Stomatology. 2002, 20(02):  128-130. 
    Abstract ( 992 )   HTML ( 24 )   PDF(pc) (158KB) ( 786 )   Save
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    Objective:The aim of this study is to evaluate clinical effects of early removal ofmaxillary mesiodens on reducingwidened di- astema of maxillary incisors in children.Methods:Totally 76 children with widened diastema of maxillary incisors were classified according to the aetiology of diastema. The mesiodens were removed, and patients were followed up for 3 years to investigate the changes of diastema.Results:The widened diastema of maxillary incisors in children was associated with central mesiodens (46P 47), as the rate of diastema in individuals with mesiodens was higher than thatwithout mesiodens (P<0105). The diastema of maxillary incisorswould frequently close automatically if central mesiodens had been removed early.Conclusion:The diastemawith space larger than 4mm of maxillary incisorswas associated with mesiodens, thus early removal of mesiodens could reduce diastema in children.

    Clinical Evaluation of the Titanium Metal Porcelain Restoration
    Zhang Chunyuan, He Yongjiang, Huang Hongyuan
    West China Journal of Stomatology. 2002, 20(02):  131-133. 
    Abstract ( 730 )   HTML ( 19 )   PDF(pc) (143KB) ( 520 )   Save
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    Objective:The purpose of this study was to evaluate the clinical performance of the titanium metal porcelain restoration. Methods:The cases in this evaluationwere divided into two groups. The experimental group consisted of 42 cases restoredwith the titanium metal porcelain restoration; the other 45 cases restored with Ni-Cr alloy porcelain restoration served as the control. The clinical performance of these restorationswas observed at1-month and 18-month follow-up. The evaluator examined the restoration for shade, marginal color, marginal fit, plaque index, gingival index, and porcelain defect.Results:Forthe shade, 92.8% of the cases in the experimental group were judged as satisfactory at 1-month and 18-month visit, whereas 91.1% in the control were evaluated similarly at the same visit. There was the marginal discoloration of 4 cases in the experimental group. But there was the marginal discoloration of 5~7 cases in the control. There were no significant difference in shade, marginal color, marginal fit, PLI andGI between the two groups .The cracking and chipping and separation of porcelainwere notoccurred.Conclusion:The ti- tanium metal porcelain restoration should be used for the clinical application compared with the Ni-Cr alloy porcelain restoration.

    Ameloblastic Fibroma and Ameloblastic Fibrosarcoma
    ZhongMing, Wang Jie, Wang Zhaoyuan, et al
    West China Journal of Stomatology. 2002, 20(02):  134-137. 
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    Objective: The objective of this studywas to observe the interstitial cell of ameloblastic fibroma (AF) and ameloblastic fibro- sarcoma (AFS) and elucidate their biological characters.Methods: 11 cases of AF (in these 3 cases recurred) and 3 cases of AFS (in these 3 cases recurred and changed malignantly) were stained by HE, scanned by lightmicroscope, in which 5 cases of fresh tumor tissue, including 3 cases of AF and 2 cases of AFS, were scanned by the electric microscope.Results: Comparing with AF, interstitial cells of AFS increased, and atypical cells were usually present. Fibroblasts, fibrohistocytes, histocytes, un- differentiated mesenchymal cells and myofibroblasts were also found in the tumor tissue. The ameloblastic epitheliums was lack in 2P3 AFS.Conclusion: Decreased or lack epithelia may be associated with excessive hyperplasia in AFS. Interstitial cells of AFS may transform malignantly due to various stimulation.

    Morphological Observation of Buccal Mucosa Carcinoma Inhibited by Monoclonal Antibodies of Human Vascular Endothelial Growth Factor
    Fang Silian, Wang Dazhang, Yang Xichuan,et al
    West China Journal of Stomatology. 2002, 20(02):  138-140. 
    Abstract ( 785 )   HTML ( 18 )   PDF(pc) (247KB) ( 625 )   Save
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    Objective:The purpose of this studywas to investigate the mechanism of the inhibited effects of anti-human vascularendothe- lial growth factor (VEGF) monoclonal antibodies E11on the growth of buccal mucosal carcinoma.Methods:E11was hypodermic and celiac injected into BALBPc nuPnumice, whichwere transplantedwith buccal carcinoma. The saline was injected as the nega- tive control. Mice were killed on the 18th day and the pathological alteration of tumor was evaluated.Results:Microscopically, massive necrosis and decreased vascular density was observed in tumor tissues treated with E11. Correspondentwith the aforemen- tioned phenomena, degeneration and apoptosis was also found in the tumor cells. For the first time, degeneration and destruction of the vascular endothelial cells in the tumor tissues treated with E11were observed using microscopy and transmission electron mi- croscopy examination.Conclusion:The study demonstrated that E11inhibited the tumor angiogenesis by blocking the action of VEGF and resulted in significantinhibitory effects on the tumorgrowth. The resultwould offer a therapeutic base to the clinical ap- plication of the anti-human VEGF monoclonal antibodies.

    Expression of Transforming Growth Factor-beta 1 in Mandibular Distraction Osteogenesis
    Hu Jing, Li Jihua, Tang Zhenglong, et al
    West China Journal of Stomatology. 2002, 20(02):  141-143. 
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    Objective:The purpose of this studywas to investigate the expression of TGF-B1in the regenerated bone after the operation of the mandibular osteodistraction.Methods:Bilateral mandibular osteotomies were performed in 15 goats. The mandibles were lengthened 10 mm using a custom-made distractorwith a rate of 1 mmPd. 3 goatswere killed respectively atthe end of delayed pe- riod (7 days), and 0, 7, 14 and 28 days after completion of distraction. The distracted callus from all animalswere harvested and processed for immunohistochemical detection of TGF-B1.Results:Staining for TGF-B1was localized in mesenchymal cells of the periosteal region atthe end of delay period. On 0, 7 and 14th day after completion of distraction, a marked increase inTGF-B1ex- pressionwas seen in the regenerated bone, and mainly localized in osteoblasts. On the 28th day after the distraction, TGF-B1 showed weak staining in the distracted callus.Conclusion:TGF-Bappears to play an important role in bone regeneration afterman- dibular osteodistraction.

    The Detection of Exon Mutation of hMSH2 in Tissues of Oral Squamous Cell Carcinoma
    Cheng Bin, Xia Hongbin, Li Chunyang, et al
    West China Journal of Stomatology. 2002, 20(02):  144-146. 
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    Objective:The purpose of this study was to detect the exon mutation of mismatch repair gene hMSH2 in tissues of oral squa- mous cell carcinoma (OSCC) and investigate the role of hMSH2 in the pathogenesis of OSCC.Methods:The mutations of hMSH2 exon 5, 6, 7, 8, 9 and 12 in the tissues of 30 human OSCC cases were analyzed using PCR-SSCP.Results:The six exons of hMSH2 were amplified successfully by using PCR technique, while no mutations in these exons were identified by using PCR-SSCP.Conclusion:The structure changes of hMSH2 exons in OSCC may be different from that in hereditary non-polyposis colorectal carcinoma (HNPCC); the role of hMSH2 in carcinogenesis of OSCC needs to be evaluated further.