Developments in science and technology include the use of laser as an auxiliary device in treating oral diseases. Nd: YAG laser is convenient and safe to use. Nd: YAG laser irradiation leaves no scabby area on the wound surface, causes a mild reaction postoperation, and promotes high comfort. Therefore, this treatment has attracted increasing attention in the clinical setting. This review enumerates the applications of water-cooled pulsed Nd: YAG laser in hard and soft tissues in oral medicine. Nd: YAG laser in hard tissues can be applied in cavity preparation, acid etching, root canal preparation and sterilization, and dentin desensitization therapy. Meanwhile, the applications of this laser in soft tissues include adjunctive therapy in basic periodontitis treatment, gingival aesthetic treatment, and resection. This review suggests the importance of Nd: YAG laser as anauxiliary device in the clinical diagnosis and treatment of oral diseases.

Objective  To construct microRNA-223 overexpression and suppression lentivirus vectors and determine their effects after infecting oral squamous cell carcinoma (OSCC) cell line. Methods  Lentivirus vectors GV229 and GV232 were cut by the restriction sites of AgeⅠ and EcoRⅠ and connected to the target gene, which contained mature microRNA-223 and microRNA-223 oligonucleotide. Real-time polymerase chain reaction (PCR) method was used to detect the microRNA-223 expression level after infecting the recombinant lentivirus vector into the OSCC cell line. Results  The successful construction of microRNA-223 recombinant lentivirus vectors was confirmed by the PCR method and DNA sequencing. HN-30 cell infected with microRNA-223 overexpression vector showed a significant increased in microRNA-223 expression, whereas HN-30 cell infected with microRNA-223 inhibitor vector suppressed microRNA-223 expression. Conclusion  The microRNA-223 overexpression and suppression lentivirus vectors are successfully constructed. These vectors could alter the expression level of microRNA-223 in OSCC cell line significantly, and provide a stable cell line for functional studies in the future.

Objective  This study investigated the role and mechanism of calcineurin (CaN)-nuclear factor of activated T cells (NFAT) pathway in the myoblast apoptosis induced by cyclic tensile strain. Methods  Myoblasts were cultured using an in vitro-mechanical stimulation model and imposed with tension for different hours with a multi-channel cell stress loading system. Cyclosporine (CsA) was used as CaN inhibitor to clarify the role of CaN in the apoptosis induced by cyclic stress. Hochest 33258 staining and flow cytometry detection were performed to detect the apoptotic cells. Real-time polymerase chain reaction was conducted to detect the mRNA expression of CaN and NFAT. Protein levels of NFAT3 were evaluated by Western blot. Results  The apoptosis rate increased with the extension of loading time. The mRNA expression of the CaN subunits, CnA and CnB, and the protein levels of NFAT3 also increased. When the myoblasts were incubated with CsA, the apoptosis rate decreased, the mRNA expression of CnA and NFAT3 significantly decreased, and the NFAT3 protein expression levels became significantly lower than those of the groups without CsA. Conclusion  Continuous cyclic tensile stress can induce myoblast apoptosis. The CaN-NFAT signaling pathway may be involved in the cyclic stretch-induced apoptosis of myoblasts.

Objective  To evaluate the effect of Fe2O3 and CeO2 as colorants on yttria stabilized tetragonal zirconia polycrystals (Y-TZP) powder. Methods  The spray granulation slurry of colored zirconia was prepared with different concentrations of Fe2O3 (0.15%) and CeO2 (4%), which were added in Y-TZP. Zirconia powder was made by spray granulation. The powder specimens were divided into three groups: uncolored zirconia, Fe2O3 (0.15%) zirconia, and CeO2 (4%) zirconia. The particle morphologies of the powder specimens were measured with a laser particle size analyzer and an optical microscope. Results  The differences in D50 among the three groups were statistically significant (P<0.05). Group Fe2O3  showed a significant difference from groups CeO2 and uncolored zirconia (P<0.05). Group uncolored zirconia showed no significant difference from group CeO2 (P>0.05). Mostly spherical powder was observed in the three groups. Conclusion  Fe2O3 as a colorant can affect particles, whereas CeO2 has no effect.

Objective  To evaluate the bond strength and durability of a self-adhesive resin cement with a zirconia ceramic pretreated by a zirconia primer. Methods  Zirconia ceramic (Vita Inceram YZ) plates with a thickness of 2.5 mm were fired, polished, and then cleaned. Half of the polished ceramic plates were sandblasted with 50 μm alumina particles at 0.3 MPa for 20 s. The surface compound weight ratios were measured via X-ray fluorescence microscopy. The polished and sandblasted ceramic plates were directly bonded with self-adhesive resin cement (Biscem) or were pretreated by a zirconia primer (Z Primer Plus) before bonding with Biscem. The specimens of each test group were divided into two subgroups (n=10) and subjected to the shear test after 0 and 10 000 thermal cycles. The data were analyzed via three-way ANOVA. Results  After air abrasion, 8.27% weight ratio of alumina attached to the zirconia surface. Compared with air abrasion, primer treatment more significantly improved the primary resin bond strength of the zirconia ceramic. The primary resin bond strength of the zirconia ceramic with no primer treatment was not affected by thermocycling (P>0.05). However, the primary resin bond strength of the zirconia ceramic with primer treatment was significantly decreased by thermocycling (P<0.05). Conclusion  Primer treatment can improve the primary resin bond strengths of zirconia ceramics. However, the bond interface of the primer is not stable and rapidly degraded during thermocycling.

Objective  To investigate the effects of different tooth preparations on three-dimensional adaption of computer aided design and computer aided manufacturing (CAD/CAM) crowns based on the reverse engineering. Methods  The tooth preparation model of the left maxillary first molar was scanned to build five different tooth preparations using the NX Imageware 13.2 software. The resin cores (n=8) were designed with the exocad software. The scanning data of the inner surface of each resin core were used to analyze the three-dimensional adaption with the Geomagic Qualify 12 software. Results  According to the color-coded deviation images, the deviation of the heavy chamfer shoulder was the smallest and the most uniform, whereas the other groups with sharp lines showed large deviation. After statistical analysis, the total deviation of the heavy chamfer shoulder, 135° shoulder, feather shoulder, 90° shoulder with lipped margins, and sharp marginal ridges preparation were (16.88±2.83), (26.88±3.61), (53.56±4.30), (51.38±4.46), and (47.19±4.62) μm. A statistical significance was observed between the heavy chamfer and 135° shoulders (P<0.05). The other groups fitted poorly, without statistical significance between each group (P>0.05). Conclusion  Three-dimensional analysis using a computer is a preferable method to study the three- dimensional adaption of crowns. The heavy chamfer shoulder and round line preparation are clinically recommended. However, feather shoulder, 90° shoulder with lipped margins, and sharp marginal ridge preparation should be avoided.

Objective  To evaluate the effect of different auxiliary resistance forms on the resistance and marginal fitness of complete crowns for short molar preparations. Methods  A total of 70 Nissin resin teeth were prepared with 20° total occlusal convergence, 2.5 mm of occlusocervical height, and a shallow finish line on a milling machine. The milled preparations were then randomly assigned to 7 groups of 10. The first group was used as the control group. A total of 30 dies were modified by preparing interproximal grooves with angles of 0°, 6°, and 20° centered on the mesial and distal surfaces of the dies. The rest of the teeth were prepared with occlusal holes in the center of the occlusal surface milled with the same burs to form 0°, 6°, and 20° holes. Cobalt–chromium copings were fabricated for all specimens. The marginal gap of specific points on the axial surface was measured before and after cementation. The resistance of each specimen was evaluated by applying an external force at an angle of 45° to the long axis of the die by using a universal testing machine in a lingual to buccal direction. The maximum force applied before crown dislodgement was measured. Data were analyzed using the SAS 9.2 software. Results  The results showed that the 0° groove, 0° hole, and 6° hole were effective in improving the resistance of the complete crowns (P<0.05). The 0° groove, 6° groove, 0° hole, 6° hole, and 20° hole had significant difference with the control group in terms of marginal discrepancies (P<0.05). Conclusion  Auxiliary resistance forms with less degree indicate greater resistance force but worse marginal fitness. In clinical practice, if the resistance of a preparation is enough, the auxiliary resistance forms should be avoided from being used.

Objective  To investigate a method of designing an accurate and scientific shade guide, especially used for judging the effect of tooth whitening, by analyzing the colorimetric values of discolored teeth statistically. Methods  One hundred thirty-six pictures of patients who had been receiving the Beyond cold light whitening treatment from February 2009 to July 2014 were analyzed, including 25 tetracycline teeth, 61 mottled-enamel teeth, and 50 yellow teeth. The colorimetric values of discolored teeth were measured. The L* values of shade tabs were calculated by hierarchical clustering of those of discolored teeth. The a* and b* values of shade tabs were the mean of those observed for discolored teeth. Accordingly, different shade guides were designed for each type of discolored teeth, and the effects were evaluated. Results  A statistically significant difference in colorimetric values was found among the three types of discolored teeth. Compared with the Vitapan Classical shade guide, the shade guides designed through the present method were more scientific and accurate in judging the effect of tooth whitening. Moreover, the arrangement of shade tabs was more logical, and the color difference between shade tabs and discolored teeth was smaller. Conclusion  The proposed designing method is theoretically feasible, although its clinical effect has yet to be proven.

Objective  To investigate the anxiety disorders and influence factors that occur in adolescent patients with cleft lip and palate and to provide theoretical foundation for mental intervention. Methods  A total of 120 adolescent patients with cleft lip and palate were investigated using a general information questionnaire, the self-rating anxiety scale, and the social support rating scale (SSRS). The influence factors of anxiety disorders were analyzed. Results  The effective questionnaires were 119. The occurrence rate of anxiety disorder in adolescent patients was 49.6% (59/119), and the occurrence rates of mild, moderate, and severe anxieties were 41.2% (49/119), 7.6% (9/119), and 0.8% (1/119), respectively. The gender, residential area, disease category, family status (one child or no children), and incidence rate of anxiety disorder in patients were statistically different (P<0.05). The SSRS scores of patients with anxiety disorder were lower than those of patients without anxiety disorder (P<0.05). Multiple regression analysis showed that gender and social support were predictive factors of the occurrence of anxiety disorder (R=0.318). Conclusion  A high anxiety disorder rate occurred in adolescent patients with cleft lip and palate. Gender and social support were important influencing factors for anxiety disorder. In the after-mental intervention, considerable attention should be given to the anxiety disorders of patients and improve their mental health.

Objective  The aim of this study was to compare the mandibular position when speaking with the intercuspal position and to check the stability of phonetics when determining the horizontal jaw relation in healthy adults. Methods  A total of 19 healthy volunteers were recruited. Seven Chinese letters, namely, /xi/, /er/, /yi/, /ci/, /mi/, /ni/, and /ri/, were chosen in the test. O-bite was used to record the mandibular position when speaking these letters. A full-adjusted articulator was used to find the mandibular position during speech, and the mandibular position was measured using a vernier caliper. The mandibular position during speech with intercuspal position was compared in both anterior-posterior and left-right directions of the horizontal plane. Multi-factor analysis of variance was conducted for the statistical analysis of the effect of objects and letters on the mandibular position. Results  1) The mandibular position was in front of the intercuspal occlusion position when speaking all seven letters, and almost no deviation was observed in the left and right directions (the mandibular position value of 82% was in the range of 0.5 mm). 2) Different objects had different mandibular positions during speech, whereas different letters did not. The distance between the centric relation position and the intercuspal position had a positive correlation with the range of the mandibular position during speech. Conclusion  The mandibular position was in front of the intercuspal position when speaking all seven words in the test. In the same object, the mandibular position was stable during speech.

Objective  To study the influence of nasolabial angle alteration on facial profile attractiveness and investigate the perception differences in profile attractiveness among laypeople. Methods  A young Chinese female with normal hard and soft tissue cephalometric values was chosen as a research object. Profile photograph was taken in a natural head position. Photoshop software was chosen to rotate the nose tip and upper lip, thus changing the degree and direction of nasolabial angle. A total of 33 different profile pictures were achieved. Thirty-three professional orthodontists and 64 non-professionals were chosen to score these 33 pictures. Results  When the upper lip position was fixed, the profile was considerably attractive because the angle of nasal tip was not changed or altered. When the nasal tip rotation angle was fixed, profiles with a retroclined upper lip were considered significantly attractive by the layperson and professional groups. Regardless of the direction of the nasal tip rotation, the respondents considered the profile with a retroclined upper lip highly attractive. Conclusion  The soft tissue profile with a retroclined upper lip looks considerably attractive in Chinese female populations. Therefore, during an orthodontic treatment, appropriate retraction of the incisor is recommended to improve soft tissue profile attractiveness.

Objective  To evaluate the operation time and clinical effect of three types of materials (i.e., total-etching adhesive, self-etching adhesive, resin-modified glass ionomer cement) that are used to bond removable thermoplastic appliances. Methods  Thirty malocclusion patients (156 attachments) with removable thermoplastic appliances were randomly divided into three groups, with 10 individuals each. Attachments of groups A and B were bonded using 3M Adper Single Bond 2 and 3M Adper Easy One, respectively; both adhesives utilized 3M Z350 nano composite resin. Attachments of group C was directly bonded using GC Fuji Ortho LC. The operation time of each attachment was recorded. Failure rates of adhesion were evaluated during adhesion, 1 month after treatment, and 6 months after treatment. Results  The operation time of group C was shorter than those of groups A and B (P<0.01). Significant difference of adhesion failure rates was not found among the three groups (P>0.05). No significant difference of adhesion failure rates was also observed in different times of the same group (P>0.05). Conclusion  The attachment stability of the three types of materials achieved satisfactory effects. However, the operation method of resin-modified glass ionomer cement is more concise and suitable for clinical promotion.

Objective  This study was performed to determine the feasibility of digital virtual positioning of braces in clinical applications. Methods  We determined the positions of brackets in 28 teeth of 15 cases according to positioning methods that use bracket height or root information. Final status was generated by OrthoRx software. Treatment results were assessed with American board of orthodontics objective grading system (ABO-OGS). Results  The deduction points in the marginal ridge height were significantly decreased after treatment using the two methods (P<0.05). However, no statistically significant difference was found in the deduction points in the marginal ridge height between the two methods (P>0.05). No improvement was found in the deduction points in root parallelism with both methods. No statistical significance was found in the deduction points in root parallelism before and after treatments using both methods. The deduction points in alignment and the three scoring components were significantly decreased after treatment using the two positioning methods. In addition, statistically significant differences were found in the deduction points in alignment between two methods (P<0.05). Conclusion  By using OrthoRx software, we achieved effective therapeutic treatment in reconstructing three-dimensional digital modes using two different bracket-positioning methods. The positioning method that used root information is more accurate compared with the bracket height positioning method. This study provides an experimental basis for bracket accuracy in the mouth.

Objective  To investigate the application of osteotomy template manufactured via 3D printing technique in bilateral sagittal split osteotomy (BSSO). Methods  The patient group consisted of 32 patients (17 males and 15 females) with mandibular hypoplasia who underwent a BSSO setback (Hunsuck modification; 64 splits). The mean age at the time of surgery was 23.5 years (range 19–35 years). All patients were scanned using cone beam computed tomography (CBCT) to create a 3D model of the mandibular, and the osteotomy template of the inner horizontal ramus of mandible bone incision was manufactured via 3D printing technique. All splits underwent operation with or without the osteotomy template by either a young doctor (attending doctor) or a doctor with extensive orthognathic surgery experience (chief doctor). The time it took to perform the mandible bone incision of the inner horizontal ramus of each group was recorded. Postoperative CBCT scan was performed, and the lingual split scale was used to assess the effect of the operation. Results  Primary healing of incisions was observed in all patients, and no serious complications occurred. The time it took to perform the mandible bone incision of the inner horizontal ramus was significantly different in the four groups (F=30.059, P<0.05), and it was longer in the group of the attending doctor without osteotomy template than in the other three groups (P<0.05). No significant difference was observed in the other groups (P>0.05). Although all splits (n=64) were performed according to the standardized protocol, only 59.38% (38/64) of the fracture lines run according to the Hunsuck’s description. By contrast, only 21.88% (14/64) run through the mandibular canal and 18.75% (12/64) was split. The database was analyzed using crosstabs and via Fisher exact test. The split pattern was influenced by the application of an osteotomy template (P<0.05). Conclusion  The application of osteotomy template manufactured via 3D printing technique in BSSO was effective, which enabled the young doctor to complete the operation faster and with good results.

Objective The aim of this study was to determine the accuracy of personalized implant fabricated via 3D
printing and fused deposition modeling technique (FDM) and to compare the results with a real tooth. Methods Six prepared extracted orthodontic teeth (in vivo) were scanned via cone beam computed tomography (CBCT) to obtain 3D data and to build the data models by using Mimics 15.0 software. The extracted orthodontic teeth (in vitro) and the personalized implants designed via 3D printing and FDM were scanned via CBCT to obtain data and to build the data models at the same parameters. The 3D deviations were compared among the in vivo teeth data models, in vitro teeth data models, and printing personalized implant data models by using the Geomagic studio software. Results The average deviations of high and low areas between date models of in vivo teeth and personalized implants were 0.19 mm and -0.16 mm, respectively, and the average deviations between in vitro and in vivo teeth were 0.14 mm and -0.07 mm, respectively. The independent t test showed that no statistically significant difference was observed between the two groups (P>0.05). Conclusion 1) The personalized dental implants were manufactured via 3D printing and FDM with a high degree of precision. 2) Errors between the data models of in vitro and in vivo teeth were observed at the same CBCT parameters.

Objective  This study investigates the circadian variation rules of the clock gene Per2 and clock-controlled genes of vascular endothelial growth factor (VEGF), Ki67, c-Myc, and P53 in different stages of carcinogenesis in buccal mucosa carcinoma and their roles in the development of buccal mucosa carcinoma. Methods  Ninety Syrian golden hamsters were housed under 12 h light/12 h dark cycles. Dimethylbenzanthracene (DMBA) was used to establish the carcinoma model by smearing the golden hamster buccal mucosa. Before DMBA painting and after 6 and 14 weeks, the hamsters were sacrificed at six time points within a period of 24 h (i.e., 4, 8, 12, 16, 20, and 24 h after light onset), and the normal buccal mucosa, precancerous lesions, and cancer tissues were simultaneously obtained. Hematoxylin and eosin stained sections were prepared to observe the canceration of each tissue. Real time polymerase chain reaction was used to detect the mRNA expression of Per2, VEGF, Ki67, c-Myc, and P53. Cosine analysis was employed to determine the circadian-rhythm variations of Per2, VEGF, Ki67, c-Myc, and P53 mRNA expression in terms of median, amplitude, and acrophase. Results  The expression of Per2, VEGF, P53, and c-Myc mRNA in three different stages appeared with circadian rhythms (P<0.05), whereas the Ki67 mRNA was expressed with circadian rhythm only in normal and precancerous lesion stages (P<0.05). The midline-estimating statistic of rhythms (MESORs) of Per2 and P53 mRNA were significantly down-regulated with the development of cancer (P<0.05), whereas the MESORs of VEGF, c-Myc, and Ki67 mRNA were up-regulated (P<0.05). The amplitude of P53 mRNA significantly decreased with the development of cancer (P<0.05). Moreover, compared with the normal group, the amplitudes of Per2, VEGF, Ki67, and c-Myc mRNA significantly increased in precancerous lesions and cancer tissue (P<0.05). In precancerous stage, the acrophases of Per2, VEGF, and c-Myc mRNA were earlier than that in the normal group, whereas that of Ki67 and P53 mRNA were delayed. Conclusion  The circadian-rhythm characteristics of the clock gene Per2 and clock-controlled gene expression of VEGF, Ki67, c-Myc, and P53 mRNA have changed with the occurrence and development of carcinoma.

Objective  To investigate the expression of full-length spleen tyrosine kinase [SYK (L)] mRNA and protein in human oral squamous cell carcinoma (OSCC) as well as its possible effects on the invasion and metastasis of OSCC. Methods  The expression of SYK (L) was detected in 27 cases of OSCC tissues and its matched adjacent non-cancerous tissues by real-time quantitative polymerase chain reaction (RT-qPCR), Western blot, and immunohistochemistry. Fourteen cases of normal oral gingival tissues were also analyzed as a normal control. Results  Reduced mRNA and protein expression of SYK (L) in OSCC tissues was observed compared with that in normal oral gingival tissues (P<0.01) and adjacent non-cancerous tissues (P<0.05). SYK(L) expression was significantly associated with lymph-node metastasis (P<0.05). Conclusion  SYK(L) is a candidate tumor suppressor for OSCC tissues, and has an inhibitive effect on the initiation, proliferation, and lymph-node metastasis of human OSCC.

Objective  To investigate the effects of oral cancer-associated fibroblasts (CAFs) on lymphangiogenesis in oral squamous cell carcinoma (OSCC). Methods  CAFs and normal fibroblasts (NFs) were obtained from the tissues of patients with OSCC who did not receive radio-chemotherapy before operation. And the CAFs and NFs were isolated by method of tissue block and identified by immunohistochemical staining. The effects of CAFs (group A) and NFs (group B) to human lymphatic endothelial cells (HLEC) were detected by using a 24-multiwell  transwell cell culture chamber. DMEM sugar medium was as blank control group. The number of proliferative, migratory, invasive and tubes of HLEC were counted under inverted phase contrast microscope. Results  The proliferative number of HLEC of group A for 96, 144, 196 h was significantly higher than that of group B and blank control group, group B higher than blank control group (P<0.01). The migratory and invasive number of HLEC of group A for 96 h was significantly higher than that of group B and blank control group, group B higher than blank control group (P<0.01). The number of tube formation of HLEC of group A for 24 h was significantly higher than that of group B and blank control group, group B higher than blank control group (P<0.01). Conclusion  CAFs promote HLEC’s proliferation, migration, invasion, tube formation, and these effects are stronger than NFs.

Objective  To detect the expression levels of programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) in the peripheral blood of patients with oral squamous cell carcinoma (OSCC) and to discuss their biological and clinical significance. Methods  PD-1/PD-L1 expression on the surface of T-lymphocytes and the counts of T-lymphocyte subpopulations of peripheral blood in 82 patients with OSCC (OSCC group) and 25 healthy controls (control group) were examined via flow cytometry. The expression levels of soluble PD-1 (sPD-1) and soluble PD-L1 (sPD-L1) in the serum were observed through enzyme-link immunology method. The data were tested and analyzed with SPSS 17.0 software. Results  The percentage of CD8+ T cells in the OSCC group was significantly higher than that in the control group (P<0.05), whereas the percentages of CD3+ and CD4+ T cells as well as CD4+/CD8+ ratio were significantly lower than those in the control group (P<0.05). The positive rates of PD-1 and PD-L1 in CD3+ and CD4+ T cells in OSCC peripheral blood were remarkably higher than those in the control group (P<0.01). Difference was not observed between the expression levels of sPD-1 in the serum of OSCC group and those in the control group (P>0.05), but the average of sPD-L1 was remarkably higher than that in the control group (P<0.05). sPD-L1 expression was related to clinical stage, tumor cell differentiation, and lymph node status (P<0.05) but not related to sex, age, tumor location, and tumor size. Conclusion  T-lymphocyte subpopulations in the peripheral blood of patients with OSCC developed immunosuppression with different degrees. PD-1 and PD-L1 expression levels on the surface of CD3+ and CD4+ T cells significantly increased. Abnormal increase in sPD-L1 expression may be associated with OSCC development.

Objective  The objective of this paper was to study the expression of related protein and Twist transcription factor of epithelial-mesenchymal transition in oral squamous cell carcinoma (OSCC) tissue and the correlations of OSCC and oral squamous cell carcinometastasis. The paper also investigated the clinical significance of expression on OSCC. Methods  The labels of epithelium materialization (E-cadherin and cytokeratin), stromal labels (N-cadherin), transcription factor Twist protein, and mRNA expression in 30 OSCC tissues were investigated via immunohistochemistry and in situ hybridization. The paper also conducted contrast analysis with clinicopathology. Results  Immunization result showed that the expressions of Twist and N-cadherin in the OSCC group were more significant than those of the normal group (P<0.05). The expressions of E-cadherin and keratin in OSCC were significantly lower than those of the normal group (P<0.05). In the moderate- and low-differentiated group of OSCC, the expressions of Twist and N-cadherin were higher than those of the high-differentiated group (P<0.05). The expressions of E-cadherin and keratin were lower than those in the high-differentiated group (P<0.05). In the lymphatic metastasis group, the expressions of Twist and N-cadherin were higher than those of no-lymphatic metastasis group (P<0.05). The expressions of E-cadherin and keratin were lower than those of the no-lymphatic metastasis group (P<0.05). Results of in situ hybridization showed that the expression of Twist mRNA in the moderate- and low-differentiated groups of OSCC, T3, and T4 groups as well as that of the lymphatic metastasis group were higher than those of the high-differentiated, T1 and T2 groups, and no-separate lymphatic metastasis group, and the differences were statistically significant (P<0.05). Conclusion  Epithelium materialization exists in OSCC tissue. Twist can enhance the invasiveness of tumor cell and promote the infiltration and metastasis of OSCC. The combined detection of Twist, E-cadherin, and N-cadherin expressions can effectively predict and estimate OSCC metastasis.

 Poly-glycerol sebacate（PGS）is a novel biodegradable elastomer, it has been widely applied in the biomedical fields of heart, blood vessel and cartilage owing to its excellent biological performance, mechanical property and degradability. Electrostatic spinning is a preparation method of tissue engineering scaffolds with the characteristics of convenience, processing controllability and cost efficiency. In this paper, the author reviewed the research process of electrostatic spinning preparation and the application in the field of tissue engineering.

MicroRNAs (miRNAs) are small non-coding RNAs that contain 22 to 25 nucleotides and play important roles in post-transcriptional regulation of target genes. MiRNAs are involved in cell proliferation, differentiation, apoptosis, inflammation, and cancer development. Alveolar bone resorption is the main clinical manifestation of periodontitis. Osteoclasts are unique cells regulated by osteoblasts and inflammatory cytokines and are responsible for bone resorption in periodontitis. Recently, miRNAs have emerged as an important regulator of osteoclast differentiation and function. In this study, we review the recent research progress on the effects of miRNAs on osteoclast differentiation and function, particularly the mechanisms of miRNAs-mediated osteoclast formation and bone loss in periodontitis.

Central malignant salivary gland tumor of the mandible is rarely observed with adenoid cystic carcinoma, which only comprises a small proportion of cancer patients. In this study, a patient with central adenoid cystic carcinoma of the mandible is presented, and relevant literature is reviewed.

The etiology of rotated maxillary central incisor is unclear, but it has a clear familial tendency. Except for the environmental factors, gene expression directly influences craniofacial growth and the types of malocclusion deformity. In this article, a case of 180° rotated left maxillary central incisor of a male with family history of the deformity was reported. Relevant literature was also reviewed.