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Effect of Rapid Maxillary Expansion under the Background of Multidisciplinary Treatment HU Min, SONG Dongsheng 2022, 38(5): 391-395.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.001 Abstract ( 363 )   PDF (1062KB) ( 521 )   Rapid maxillary expansion (RME) is a common method to solve the problem of maxillary arch stenosis and transverse maxillary deficiency in orthodontics. In recent years, with the in-depth study of the mechanism of RME, its extensive biological effects have attracted attention. By adjusting the physiological function of pharyngeal and nasal cavity, RME plays a positive role in the treatment of diseases such as otitis media with effusion and nasal obstruction; by improving airway and respiratory function, it can reduce sleep disorders such as obstructive sleep apnea syndrome, sleep bruxism, and nocturnal enuresis in children; by matching jaws width and improving the occlusal relationship of posterior teeth, it may relieve the symptoms of temporomandibular joint disorders. In addition, RME has potential effects on physiological functions such as masticatory muscle function, pronunciation, and head and neck posture. Making use of the extensive biological effects of RME and giving full play to the comprehensive therapeutic effect of RME will provide help for the treatment of multidisciplinary diseases. This article will summarize the role of RME in multidisciplinary diagnosis and treatment combined with the latest research results at home and abroad, so as to provide reference for the interdisciplinary and comprehensive application of RME. References | Related Articles | Metrics

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Research Progress on Quaternary Ammonium Monomer Dimethylaminododecyl Methacrylate-modified Dental Materials FENG Xue, CHENG Lei 2022, 38(5): 396-399.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.002 Abstract ( 319 )   PDF (836KB) ( 480 )   The ecological unbalance between oral microbes and host may induce infectious diseases, such as dental caries, periodontal diseases, candidiasis, peri-implantitis, and so on. Therefore, it is beneficial for dental materials with antimicrobial properties to prevent these illnesses. Dimethylaminododecyl methacrylate (DMADDM), a kind of quaternary ammonium salts, presents wide and remarkable antibacterial properties and is able to crosslink with substrate materials. DMADDM-modified dental materials can function as a non-releasing and long-lasting antibiotics. This paper reviews the antibiotic properties, antibacterial mechanism, and study of bacterial resistance of DMADDM-modified dental materials in recent years References | Related Articles | Metrics

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Advances in Biomarkers Related to Orthodontic Tooth Movement in Gingival Crevicular Fluid GUAN Jiani, YAN Bin 2022, 38(5): 400-403.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.003 Abstract ( 308 )   PDF (818KB) ( 609 )   Gingival crevicular fluid is a kind of tissue permeation fluid in gingival sulcus and periodontal pocket. The application of orthodontic force to teeth will lead to remodeling of periodontal tissue and changes of biochemical mediators in gingival crevicular fluid. Analyzing the changes of specific biomarkers in gingival crevicular fluid during orthodontic tooth movement is helpful for doctors to understand the remodeling status of patients' periodontal tissue and monitor tooth movement, so as to develop personalized orthodontic treatment plan for patients, shorten the treatment period, and avoid adverse reactions. At present, the biological processes of biomarkers related to orthodontic tooth movement in gingival crevicular fluid can be divided into three categories: inflammation, bone resorption and formation, and tissue injury and repair. This article reviews the potential biomarkers related to orthodontic tooth movement in gingival crevicular fluid. References | Related Articles | Metrics

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Application and Research Progress of Biphasic Calcium Phosphate Ceramics in Dental Implant SHEN Hongyu, SONG Ke 2022, 38(5): 404-407.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.004 Abstract ( 432 )   PDF (1420KB) ( 426 )   Dental implant technology is widely used for the patients with defected dentitions to repair their missing teeth. Osseointegration between implant and alveolar bone is the key factor to the success of implant surgery. The biphasic calcium phosphate (BCP), a bioceramic material, can be used not only as bone substitute material for the bone augmentation program around the dental implant, but also as coating material for implant surface to promote osseointegration. BCP ceramics is widely used in clinical medicine, which has outstanding properties: biocompatibility, bioactivity, stability, biodegradability, osteoconductivity, and potential osteoinductive. This paper reviews the application and research survey of BCP ceramics in dental implant, with hope to provide some beneficial references for the clinical application of BCP ceramics in this field. References | Related Articles | Metrics

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Advance in Endodontic Regeneration Treatment of Immature Permanent Teeth Reziyaguli·AKEMU, YANG Guobin 2022, 38(5): 408-411.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.005 Abstract ( 421 )   PDF (878KB) ( 809 )   Endodontic regeneration treatment refers the best use of biological and tissue engineering techniques that protect dental pulp cells, dental papilla mesenchymal stem cells, and periodontal ligament stem cells by perfecting and effective root canal disinfection. Blood clots provides a good microenvironment for stem cell proliferation and differentiation and promotes the continued root development. This article introduces the historical research, biological basis, indications, procedures, efficacy evaluation, and complications of pulp revascularization of immature permanent teeth and provides guidance for clinical operations. References | Related Articles | Metrics

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High-throughput Detection of Microorganisms in Two Periodontitis ZHANG Yiling, XU Jie 2022, 38(5): 412-416.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.006 Abstract ( 192 )   PDF (1907KB) ( 411 )   Objective: To analyse the composition and differences of subgingival microorganisms between generalized aggressive periodontitis (GAgP) and severe chronic periodontitis (SCP) by high-throughput sequencing. Methods: Accordingly, 20 patients with GAgP and 22 patients with SCP were enrolled along with 20 healthy subjects. Their subgingival plaques were collected. DNA of the subgingival plaques were extracted. Subgingival bacteria were detected using the illumina Miseq sequencing platform as well as the V4 region of the 16S rDNA of bacteria. Results: The major bacteria of the GAgP and SCP groups were similar, including Porphyromonas endodontalis and so on. Additionally, the dominant bacteria in the healthy group was different from those in the GAgP and SCP groups, including Haemophilus parainfluenzae and so on. No biomarkers were present between the GAgP and SCP groups. Moreover, different biomarkers were compared between the healthy group and the GAgP or the SCP. Conclusion: The GAgP and SCP groups contained similar microbial communities. However, the GAgP or SCP groups as well as the healthy subjects were comprised of different microbial communities. There were no biomarkers between the GAgP and SCP groups. References | Related Articles | Metrics

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Effect of Conditional Knockout of Fam20C on Expression of MMP-1 and TIMP-1 in Periodontal Ligament of Mice YUAN Zhaoyang, WU Guodong, QI Hao, MA Su, LIU Peihong 2022, 38(5): 417-423.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.007 Abstract ( 218 )   PDF (9888KB) ( 195 )   Objective: To investigate the effect of knocking down Fam20C driven by the 3.6 kb Col1α1 promoter on periodontal tissues in mice. Methods: Paraffin sections of the mandibular molar region were routinely made from paraffin blocks of mandibular tissues of 3.6 kb Col1α1-Cre; Fam20Cfl/fl mice and normal control mice in the same litter at 4 and 12 weeks of age. The paraffin sections were used for HE staining, Masson staining, and immunohistochemical staining. The histological changes of cementum, alveolar bone, and periodontal ligament in the molar region of mice in all groups were observed. Optical density values were measured to analyze the differential expression of MMP-1 and TIMP-1 in the periodontal ligament. Results: Compared with normal control mice, the cellular cementum in the molar area of 4-week-old Fam20C knockout mice became thinner; The height of alveolar bone between molars was reduced. The diameter of collagen fiber bundles in the periodontal ligament was decreased, and some fiber bundles were loose and disordered. The positive expression of MMP-1 in periodontal ligament was significantly increased (P<0.05). The positive expression of TIMP-1 was slightly decreased (P>0.05). The MMP-1/TIMP-1 ratio was significantly increased (P<0.05). 12-week-old Fam20C knockout mice had more severe periodontal tissue lesions than 4-week-old knockout mice. Their cellular cementum was significantly decreased. The height of alveolar bone between molars was significantly reduced. The collagen fiber bundles of the periodontal ligament were disorganized. They were slenderer and sparse. A large number of collagen fiber bundles below the root neck were broken and detached from the surface of cementum and alveolar bone. The trend of differential expression of MMP-1 and TIMP-1 in the periodontal ligament was consistent with the 4-week-old group. Conclusion: The knockout of Fam20C driven by the 3.6 kb Col1α1 promoter may lead to periodontal lesions in mice by up-regulating the MMP-1/TIMP-1 ratio in the periodontal ligament. References | Related Articles | Metrics

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Jumonji Domain-containing Protein 3 Regulates the Inflammatory Response of Human Periodontal Ligament Cells WANG Puyu, SUO Lai 2022, 38(5): 424-428.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.008 Abstract ( 161 )   PDF (2209KB) ( 294 )   Objective: To investigate the role of the histone 3 lysine 27 trimethylation (H3K27me3) demethylase Jumonji domain-containing protein 3 (Jmjd3) in the regulation of the inflammatory response of human periodontal ligament cells (HPDLs). Methods: HPDLs were stimulated with lipopolysaccharide (LPS) from p.g or tumor necrosis factor-α. The expression of Jmjd3 in HPDLs was examined by quantitative real-time polymerase chain reaction (Q-PCR) and immunofluorescence. After confirmed the depletion of Jmjd3 by Q-PCR and Western blot, potential target genes were selected by silencing Jmjd3. Results: Q-PCR and immunofluorescence revealed that the expression of Jmjd3 was increased in inflamed HPDLs. Knockdown of Jmjd3 led to the suppression of inflammation-induced up-regulation of interleukin-6 and interleukin-12b. Conclusion: Jmjd3 regulated the activation of interleukin-6 and interleukin-12b in the inflammatory response of HPDLs. References | Related Articles | Metrics

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Clinical Features and Relapse Prevention of Epulis: A Retrospective Study of 234 Cases KE Xiaojing, JIN Ou, YAN Fuhua, LI Yanfen, LI Houxuan 2022, 38(5): 429-435.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.009 Abstract ( 445 )   PDF (5449KB) ( 444 )   Objective: To analyze clinical features of epulis and provide a reference for delving into the biological behavior and prevention of relapse of epulis. Methods: Patients diagnosed as epulis through outpatient and postoperative pathology at the Department of Periodontology, Nanjing Stomatological Hospital, Medical School of Nanjing University from 2018 to 2019 were retrospectively analyzed. Results: A total of 234 cases of epulides were included. The peak incidence of epulis fell in 21 to 30 years old, and the total ratio of males to females was about 1∶2.2. Female was more frequent in the group from 31 to 70 years (P<0.05), yet there was no statistically difference in the proportion of male and female under the age of 30 (P>0.05). Histopathological examination revealed fibrous epulis (121 cases, 51.71%), granuloma epulis (76 cases, 32.48%), vascular epulis (36 cases, 15.38%), and giant cell epulis (1 case, 0.43%). There was no significant difference in the distribution of the upper and lower jaws of epulis (P>0.05), and the anterior teeth area was the common location (P<0.001). In addition, epulis were mostly located on the buccal side (66.67%) and least in the edentulous area (1.28%). The size of epulis varied from 0.3 cm to 2.2 cm in diameter, most of which were distributed among the range of 0.6 cm to 1.5 cm (78.2%). Two cases had relapsed after periodontal system treatment in the short term, and the recurrence rate was 0.85%. Conclusion: Epulides are more prevalent in females and young patients(21 to 30 years old). The majority of epulides were located in the anterior region and on the buccal side. Perfect inflammation control and thorough surgical resection can effectively control the recurrence of epulis. References | Related Articles | Metrics

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Study on COX-2 Expression and Signalling Pathway in HUVECs Induced by P.gingivalis Lipopolysaccharide GAO Yuan, LI Jia, LI Weishan 2022, 38(5): 436-441.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.010 Abstract ( 158 )   PDF (1340KB) ( 180 )   Objective: To study the effect of P.gingivalis lipopolysaccharide on Cyclooxygenase-2 (Cox-2) expression in human umbilical vein endothelial cells (HUVECs), and investigate whether p38MAPK and PI3K/Akt signalling pathways involved in the regulation of COX-2 expression in HUVECs by P.g-LPS. Methods: HUVECs were cultured in vitro, and different concentrations of P.g-LPS (0.5, 1.0, 5.0, and 10.0 μg/mL) were used for stimulation for 6, 18, 24, and 36 hours. The effect of P.g-LPS on cell proliferation of HUVECs was detected by CCK-8. The expressions of COX-2 protein and gene in HUVECs were detected by Western blot and RT-qPCR. Additional, after stimulated with different concentrations of P.g-LPS(0.5, 1.0, 5.0, and 10.0 μg/mL)for 36 hours, HUVECs were added with pathway inhibitors SB203580 and LY294002. The expressions of COX-2 protein and gene in each group were detected by Western blot and RT-qPCR. Results: The proliferation activity of HUVECs decreased significantly with increasing P.g-LPS concentration (P<0.05). Compared with the control group, P.g-LPS promoted the expression of COX-2 in HUVECs in a concentration dependent manner (P<0.05). In addition, P.g-LPS activated the p38MAPK and PI3K/Akt signalling pathways. Addition of SB203580 and LY294002 inhibitors inhibited the expression of COX-2 by P.g-LPS (P<0.05). Conclusion: P.g-LPS can significantly inhibit the proliferation of HUVECs and may promote COX-2 protein and genes expression through activation of p38MAPK and PI3K/Akt pathways. References | Related Articles | Metrics

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Application of Digital Assisted Esthetic Crown Lengthening in the Second Restoration of Upper Anterior Teeth MEI Youmin, ZHANG Ying, GAO Meiqin, MA Chunyi , SUN Hantang, SUN Jinwei, XU Jiali, CHEN Minyan, CHENG Yuye 2022, 38(5): 442-446.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.011 Abstract ( 237 )   PDF (2104KB) ( 382 )   Objective: To assist the periodontal-restorative combined treatment of upper anterior teeth through digital smile design (DSD). Methods: Twelve patients (74 teeth) underwent esthetic crown lengthening surgery in the upper anterior tooth area with the aid of DSD after perfecting their teeth and periodontal treatment for one month. All-ceramic crown restoration was performed six months after the operation. Results: Postoperative PD and BOP values were statistically different (* P<0.01). Compared with preoperatively, except for 1 month after operation, the PI values at all nodes in the follow-up were significantly improved (# P<0.01). Six months and 1 year after the repair, the neck margins of all restorations were suitable, and there was no obvious gingival hyperplasia or recession. Most patients were satisfied with the final coordination of the gingival margin, the smiling effect, the diagnosis, and treatment process. Conclusion: DSD-assisted periodontal-restorative combined therapy not only maintains the health of patients, but also achieves better aesthetic effects, obtains high satisfaction, and has high clinical application value. References | Related Articles | Metrics

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Effects of Sandwich Technology and Occlusal Angle of Different Filling Materials on Stress Distribution of Non-caries Cervical Lesions LIU Xiao, CHEN Xi, LI Bao, MA Gailan, GONG Yuejun, GUO Tao 2022, 38(5): 447-453.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.012 Abstract ( 193 )   PDF (4236KB) ( 304 )   Objective: To analyze the effects of different filling materials and occlusal angles on the stress distribution of mandibular first premolars with non-caries cervical lesions by three-dimensional finite element method. Methods: A three-dimensional finite element model of mandibular first premolars with non-caries neck defect was established as control group. Four groups of material were used as the experimental group. Group A: 3M Filtek Z350XT resin-glass ionomer cement. Group B: 3M Filtek Z350XT resin-Cention N. Group C: 3M Filtek Z350XT Flowable Resin-Glass ionomer Cement. Group D: 3M Filtek Z350XT Flowable Resin -Cention N. All models were given a vertical load (0°) at the buccal tip and a lateral load (30°, 45°, 60°) at the side of the buccal tip with 100N each, and the stress distribution was analyzed using ANSYS 17.0. Results: (1) In the control group, the Von Mises stress peak value increased by 49.3%, 222.4%, and 376% under lateral loading compared with vertical loading, respectively. Compared with the control group, the dental tissue stress was significantly reduced in groups A, B, C, and D after filling, but there was only slight difference among groups. (2) With the increase of load angle, the stress peak value (MPa) of inner material was D>B>C>A. (3) With the increase of loading angle, the Von Mises stress peak of the outer material was A>B>C>D. (4) With the increase of loading angle, the stress peak value (Mpa) of adhesive in vertical loading was C>D>A>B, and the order of peak Von Mises stress in lateral loading was A>B>C>D. Conclusion: 3M Filtek Z350XT Flowable resin-Cention N material combination has more advantages in repairing the mandibular first premolars with non-caries cervical lesions under the same occlusion condition. References | Related Articles | Metrics

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Measurement of Bubble Dynamic and Thermal Effect of Er:YAG Laser Irrigation with Different Pulse Widths ZHAO Sijia, HE Xinyu, LI Yizhou, DONG Xiaoxi, NIE Mingyuan, PAN Chong, ZHAO Jizhi 2022, 38(5): 454-458.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.013 Abstract ( 282 )   PDF (1573KB) ( 350 )   Objective: To evaluate how different pulse widths affect the bubble dynamic and thermal effect of Er:YAG laser irrigation in single root canal resin tooth model. Methods: Waveforms of Er:YAG laser at different pulse width modes were measured by oscilloscope. The bubble dynamic during Er:YAG laser active irrigation (LAI) process in a single root canal resin tooth model was caught by a high-speed camera, then bubbles' maximum diameter, volume, expansion, and collapse period were counted. Temperature changes in pulp cavity were recorded by thermocouple. Results: The waveform of Er:YAG laser exhibited the properties of relaxation oscillation of solid laser. The first peak pulse width was significantly different between different pulse width modes. The bubbles' diameter, volume, collapse, and oscillation period decreased with the growth of pulse width (P<0.05), while the temperature of irrigation in pulp cavity relatively increased (P<0.05). Conclusion: Shorter pulse width of Er:YAG LAI led to larger bubble volume and lower temperature increase in pulp cavity. It might be more appropriate to apply short pulse width in Er:YAG LAI. References | Related Articles | Metrics

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Cleaning Efficacy of Andrographis Paniculata Nanoemulsion Irrigant on Root Canals SUN Jia, HAN Wei, ZHANG Shuying, GUAN Tong, JIANG Mei, SHI Yan 2022, 38(5): 459-464.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.014 Abstract ( 154 )   PDF (3027KB) ( 158 )   Objective: To evaluate the cleanliness of andrographis paniculata nanoemulsion for root canal irrigation. Methods: Fifty freshly extracted single-root canal premolars were collected and divided into five groups. During instrumentation,the nickel-titanium files,the crown-down preparation, and five irrigants were used. group A: andrographis paniculata nanoemulsion; group B: andrographis paniculata extract; group C: 1% NaClO; group D: 3% NaClO; and group E: 0.9% saline. All groups were finally irrigated with 17% EDTA and saline, respectively. Digital camera and scanning electron microscopy were used to compare the debris and smear layer scores in the apical, middle, and coronal thirds of the root canals. Results: In the apical thirds: group E showed higher debris and smear layer score than other four groups, group C had significantly higher smear layer score than group A and D (P<0.05). In the middle thirds: group C showed significantly more debris than group A and D (P<0.05). In the coronal thirds: group C had significantly higher smear layer score than group D (P<0.05). Conclusion: The cleanliness of the irrigation fluid was ranked as follows: 3% NaClO, andrographis paniculata nanoemulsion, andrographis paniculata extract, 1% NaClO, and Saline. Andrographis paniculata nanoemulsion appears to be one of the Chinese medicine to be identified as a possible intracanal irrigant. References | Related Articles | Metrics

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Study on Mechanism of Huoxue Huayu Prescription in the Treatment of Oral Lichen Planus Based on GEO Data Mining and Network Pharmacology YANG Qian, LAI Renfa, LIU Xiangning 2022, 38(5): 465-470.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.015 Abstract ( 217 )   PDF (2208KB) ( 360 )   Objective: To study the key components, potential targets, and mechanisms of Huoxue Huayu prescription in the treatment of oral lichen planus based on GEO data mining and network pharmacology. Methods: The GSE52130 data set in GEO database was crawled by R language, and differential therapeutic targets of OLP were analyzed. The chemical constituents and targets of Huoxue Huayu prescription were obtained based on TCMSP database, and the composition-target network and protein-protein interaction network were plotted using Perl software, Cytoscape software, and String. The GO and KEGG analysis of key target genes were completed by R language. Results: There were 28 key chemical components of Huoxue Huyu prescription in OLP treatment, including quercetin, kaempferol, stigmasterol, etc. And 13 core targets were found, including IL-1β, PTGS2 (COX-2), MAO, et al. KEGG analysis showed that Huoxue Huayu prescription could affect neurotransmitter metabolism, cytomegalovirus infection, and AGE-RAGE pathways. Conclusion: The result provided theoretical reference for the subsequent in depth study of TCM treatment of OLP. References | Related Articles | Metrics

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Clinical and Genetic Analysis of A Pedigree Affected with Amelogenesis Imperfecta ZHAO Tian, WANG Ningxiang, LIAO Zhuoyi, WANG Feiyang, SUN Weibin, WU Juan 2022, 38(5): 471-476.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.016 Abstract ( 211 )   PDF (3031KB) ( 334 )   Objective: To explore the clinical and genetic characteristics of a Chinese pedigree affected with amelogenesis imperfecta (AI). Methods: Clinical data of the pedigree members were collected and genomic DNA were extracted from peripheral blood samples. Whole exome sequencing was used to identify mutations and confirmed by Sanger sequencing. Results: Clinical characteristics of all the affected family members found in the present study were including: all teeth with yellowish coloration, enamel with an irregular rough surface, remaining enamel was softer than normal, and the enamel density could not be distinguished from dentin, which were consistent with autosomal dominant hypocalcified AI (ADHCAI). The proband was found to carry a known nonsense mutation (c.1366C>T) in exon 5 of the FAM83H gene, causing a truncated protein (p.Gln456*). In addation, the mutation was cosegregated among affected family members with ADHCAI phenotype but not in those that were unaffected.Conclusion: The nonsense mutation (c.1366C>T) was identified in FAM83H gene in the pedigree associated with ADHCAI, which provided a basis for molecular diagnosis and genetic counseling for this pedigree. References | Related Articles | Metrics

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Inhibition of Osteoclastogenesis by A Designed Osteoprotegerin-like Peptide WANG Jiangyue, WU Gang, TIAN Ye, BAI Ding 2022, 38(5): 477-481.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.017 Abstract ( 171 )   PDF (3038KB) ( 172 )   Objective: To design and investigate the role of peptides mimicking the binding site of osteoprotegerin (OPG) in inhibiting osteoclastogenesis and its possible mechanism. Methods: Fifty micromolar osteoprotegerin-like peptides OPGL 1, 2, and 3 were added to RANKL-induced osteoclast precursor. Tartrate-resistant acid phosphatase (TRAP) osteoclast phenotype staining, quantitative real-time PCR, and Western blot were used to test the ability of peptides. Results: OPGL2 appeared to significantly suppress RANK-induced osteoclastogenesis and led to decreased expression of TRAP, Cathepsin K (CTSK), and NFATC1 gene. OPGL2 also inhibited the expression of osteoclast-related proteins such as TRAP and C-fos. Conclusion: OPGL2 osteoprotegerin-like peptide could inhibit osteoclast differentiation, and its possible pathway was NFATC1. References | Related Articles | Metrics

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Cemental Tear in A Maxillary Lateral Incisor: A Case Report WANG Dan, CUI Jian, QUAN He, XU Weicheng 2022, 38(5): 482-483.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.018 Abstract ( 287 )   PDF (2281KB) ( 309 )   Cementum tear is a special form of root fracture, which is often treated incorrectly or delayed due to the difficulty of diagnosis. We report a cemental tear in a maxillary lateral incisor, which was not diagnosed and treated accurately in the early stage. The result was tooth extraction, because the alveolar bone is absorbed seriously. It is hoped that the review of this case can help clinicians understand and diagnose cementum tear accurately. References | Related Articles | Metrics

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Minimally Invasive Extraction of Deeply Embedded Mesiodens: A Case Report FAN Guo, WU Yang 2022, 38(5): 484-486.  DOI: 10.13701/j.cnki.kqyxyj.2022.05.019 Abstract ( 331 )   PDF (4028KB) ( 597 )   According to minimally invasive principles, the extraction of deeply embedded mesiodens procedures must avoid to injure adjacent teeth, pyriform foramen, nasal mucosa, nasal spine, and other important structures. This paper reported a case of minimally invasive extraction of two deeply embedded mesiodens medial to nasal spine. The bone structure of nasal spine was preserved by bilateral invasive approaches. References | Related Articles | Metrics