The effect of tongue reduction for preventing adverse effects in patients undergoing class III orthognathic surgery: a three-dimensional comparative analysis.

OBJECTIVES: This study aims to evaluate the potential benefits of combining tongue reduction with mandibular setback surgery in patients undergoing class III orthognathic surgery. Specifically, we investigated whether this combined approach reduced the risk of surgical relapse, condylar resorption, and airway space reduction by mitigating tongue pressure on the mandible. MATERIAL AND METHODS: The study retrospectively enrolled patients who had undergone bilateral sagittal split ramus osteotomy (BSSRO) with at least 5 mm of setback and met the criteria of a body mass index > 20 kg/m2 and tongue volume > 100 mm3. The study included 20 patients with 10 in the tongue reduction group (TR, n = 10) and 10 in the BSSRO only group (SO, n = 10). RESULTS: The volumetric changes of the total airway space were significantly different between the TR and SO groups (p = 0.028). However, no significant differences were observed in the condylar resorption and postoperative relapse between the groups (p = 0.927 and 0.913, respectively). The difference between the resorption of the anterior and posterior segments of the condyle was also statistically insignificant (p = 0.826). Postoperative counterclockwise rotation of the proximal segment only demonstrated a significant correlation with postoperative relapse (p = 0.048). CONCLUSIONS: The reduction in tongue volume demonstrated a preventive effect on the reduction of the airway space after mandibular setback, although it did not yield statistical significance concerning surgical relapse and condylar volume. The counterclockwise rotation of the proximal segment might be responsible for the forward displacement of the distal segment and postoperative relapse. However, the clinical implications of this finding should be interpreted with caution owing to the limited sample size CLINICAL RELEVANCE: Tongue reduction could potentially serve as a preventive measure in preserving the airway space and might be beneficial in mitigating the risk of obstructive sleep apnea in patients with class III deformity.

Implant placement with inferior alveolar nerve repositioning in the posterior mandible.

This case report presents inferior alveolar nerve (IAN) repositioning as a viable approach for implant placement in the mandibular molar region, where challenges of severe alveolar bone width and height deficiencies can exist. Two patients requiring implant placement in the right mandibular molar region underwent nerve transposition and lateralization. In both cases, inadequate alveolar bone height above the IAN precluded the use of short implants. The first patient exhibited an overall low alveolar ridge from the anterior to posterior regions, with a complex relationship with adjacent implant bone level and the mental nerve, complicating vertical augmentation. In the second case, although vertical bone resorption was not severe, the high positioning of the IAN within the alveolar bone due to orthognathic surgery raised concerns regarding adequate height of the implant prosthesis. Therefore, instead of onlay bone grafting, nerve transposition and lateralization were employed for implant placement. In both cases, the follow-up results demonstrated successful osseointegration of all implants and complete recovery of postoperative numbness in the lower lip and mentum area. IAN repositioning is a valuable surgical technique that allows implant placement in severely compromised posterior mandibular regions, promoting patient comfort and successful implant placement without permanent IAN damage.

Comparison of vertical bone resorption following various types of autologous block bone grafts.

BACKGROUND: This study aims to measure and compare the differences in vertical bone resorption after vertical augmentation using different types of autologous block bone. METHODS: Data were collected from 38 patients who had undergone vertical ridge augmentation using an autologous block bone before implant insertion. The patients were divided into three groups based on the donor sites: ramus bone (RB), chin bone (CB), and iliac crestal bone (IB). RESULTS: The surgical outcome of the augmentation was evaluated at the follow-up periods up to 60 months. In 38 patients, the mean amount of vertical bone gain was 8.36 ± 1.51 mm in the IB group, followed by the RB group (4.17 ± 1.31 mm) and the CB group (3.44 ± 1.08 mm). There is a significant difference in vertical bone resorption between the groups (p < 0.001), and the RB group demonstrated significantly lower resorption than the CB and IB groups (p = 0.011 and p < 0.001, respectively). The most common postoperative complications included neurosensory disturbance in the CB graft and gait disturbance in the IB graft. Out of the 92 implants inserted after augmentation, four implants were lost during the study period, resulting in an implant success rate of 95.65%. CONCLUSIONS: The RB graft might be the most suitable option for vertical augmentation in terms of maintaining postoperative vertical height and reducing morbidity, although the initial gain was greater with the IB graft compared to other block bones.

The Efficacy of the Partial Glossectomy for Prevention of Airway Volume Reduction in Orthognathic Surgery of Class III Patients.

The aim of this study was to evaluate the effects of a partial glossectomy on volumetric changes of pharyngeal airway space (PAS) in patients with mandibular setback surgery. Overall, 25 patients showing clinical features related to macroglossia treated with mandibular setback surgery were included in this retrospective study. Subjects were divided into two groups: the control group (G1, n = 13, with BSSRO) and the study group (G2, n = 12, with both BSSRO and partial glossectomy). The PAS volume of both groups was measured by the OnDemand 3D program on CBCT taken shortly before operation (T0), 3 months post-operative (T1), and 6 months post-operative (T2). A paired t-test and repeated analysis of variance (ANOVA) were used for statistical correlation. Total PAS and hypopharyngeal airway space were increased after operation in Group 2 compared to Group 1 (p < 0.05), while oropharyngeal airway space showed no significant statistical difference with the tendency of increasing. The combination of partial glossectomy and BSSRO surgical techniques had a significant effect on increasing the hypopharyngeal and total airway space in class III malocclusion patients (p < 0.05).

Retrospective clinical study of mandible fractures.

BACKGROUND: As society becomes more complex, the incidence of mandibular fractures is increasing. This study aimed to analyze the incidence and type and identify etiological factors of mandibular fractures to use them in future treatments. MATERIAL AND METHODS: Data were collected from 224 patients who visited the department of oral and maxillofacial surgery at the Kyung Hee Medical Center dental hospital during a 6-year period (2016 to 2021). A logistic regression model was used for data analysis. RESULTS: In a total of 224 patients, 362 fractures were appeared. The average age of the patients was 34.1 years, with the highest incidence in the 20s. And the ratio between male and female was 4.09:1. Symphysis fractures were the most prevalent of all patients (52.7%), followed by unilateral condyle (37.1%), angle (36.2%), bilateral condyle (9.4%), body (8%), and coronoid (2.2%). The most common cause of fracture was daily-life activity (57.6%), followed by violence (30.4%), traffic accidents (8.5%), and syncope (3.6%). Patients with symphysis fracture were at low risk (OR < 1) of angle, body, and unilateral condyle fractures. Similarly, patients with unilateral fracture were at low risk (OR < 1) of symphysis, angle, body, and others site fractures. In contrast, patient with bilateral condyle fracture were at high risk (OR > 1) of coronoid fractures. And younger patients were high risk of mandibular angle fractures. CONCLUSION: Through this study, it was confirmed that etiological factors of mandibular fractures were like those of previous studies.

Gastric cancer exosomes contribute to the field cancerization of gastric epithelial cells surrounding gastric cancer.

BACKGROUND: A dynamic molecular interaction between cancer and the surrounding normal cells is mediated through exosomes. We investigated whether exosomes derived from gastric cancer cells affected the fate of the surrounding gastric epithelial cells. METHODS: We analyzed the cell viability and immortalization of primary normal stomach epithelial cells (PNSECs) after treatment with exosomes derived from AGS gastric cancer cells and/or H. pylori CagA. Cell proliferation and apoptosis were analyzed by BrdU incorporation, flow-cytometry, and colony formation assays. We examined telomere length, expression and activity of telomerase, and expression of telomere-related genes in PNSECs treated with cancer exosomes, and in 60 gastric cancer and corresponding mucosal tissues. The differentially expressed genes and transcriptional regulation of telomere-related genes were verified using real-time qPCR and ChIP analyses, respectively. RESULTS: Gastric cancer exosomes increased cell viability and the population-doubling levels but inhibited the cellular senescence and apoptosis of PNSECs. The internalization of cancer exosomes in PNSECs dramatically increased the number of surviving colonies and induced a multilayer growth and invasion into the scaffold. Treatment of PNSECs with cancer exosomes markedly increased the expression and activity of telomerase and the T/S ratio and regulated the expression of the telomere-associated genes, heat-shock genes, and hedgehog genes. Compared to gastric mucosae, gastric cancer showed increased hTERT expression, which was positively correlated with telomere length. Interestingly, seven (46.7%) of 15 non-cancerous gastric mucosae demonstrated strong telomerase activity. CONCLUSION: These results suggest that gastric cancer exosomes induced the transformation and field cancerization of the surrounding non-cancerous gastric epithelial cells.

Removal of a suture needle: a case report.

BACKGROUND: Foreign bodies may be embedded or left behind in the oral cavity during oral surgical procedure. The loss of instruments such as impression material, surgical gauze, and broken injection needles are commonly reported in the dental field. These complications are generally symptomatic and show signs of inflammation, pain, and purulent discharge. Accidental breakage of suture needles is a rare but potentially dangerous event. CASE PRESENTATION: In this report, we present one case of lost suture needle during the procedure of flap operation at local dental clinic and its successful removal under local/general anesthesia administration via CBCT with a help of two reference needles to localize the 6-0 nylon needle and consulting with the clinician. CONCLUSION: CT scanning taken while mouth-closing may not be accurate with regard to real location measurement performed while mouth-opening. If so, other up-to-date radiographic devices and methods to retrieve a needle are recommended.

Closure of oroantral fistula: a review of local flap techniques.

Oroantral fistula (OAF), also termed oroantral communication, is an abnormal condition in which there is a communicating tract between the maxillary sinus and the oral cavity. The most common causes of this pathological communication are known to be dental implant surgery and extraction of posterior maxillary teeth. The purpose of this article is to describe OAF; introduce the approach algorithm for the treatment of OAF; and review the fundamental surgical techniques for fistula closure with their advantages and disadvantages. The author included a thorough review of the previous studies acquired from the PubMed database. Based on this review, this article presents cases of OAF patients treated with buccal flap, buccal fat pad (BFP), and palatal rotational flap techniques.

The Envelope of Segmental Movement and Airway Changes After Mandibular Anterior Subapical Osteotomy in Skeletal Class II Protrusion Patients.

INTRODUCTION: This study aimed to determine the envelope of anterior segmental movement and changes in the inferior pharyngeal airway space (IPAS) and position of the hyoid bone following mandibular anterior subapical osteotomy (ASO) under local anesthesia in skeletal Class II patients with protrusion. METHODS: The subjects were 33 skeletal Class II adult patients with lip protrusion. They were treated by extraction of 4 premolars and mandibular ASO under local anesthesia. Surgical movement of mandibular anterior segment and IPAS after surgery was evaluated by mandibular superimposition using lateral cephalograms between before and immediately after surgery. The depth of osteotomy and overlapping ratio were measured. RESULTS: The mean retraction of the mandibular incisor was 4.04 mm at the tip and 4.29 mm at the root apex. The mean vertical movement of the mandibular incisor was 3.33 mm intrusion at the tip and 3.42 mm at the root apex. The axis of the mandibular incisor did not change significantly. Patients with deep curve of Spee showed significantly more intrusion of incisors, whereas the incisor axis became more proclined. The IPAS became narrower, and the hyoid bone moved downward after surgery. The decreased IPAS was positively correlated with retraction of root apex and proclination of the mandibular incisors. CONCLUSION: To establish precise surgical treatment objectives, a balance between the amount of intrusion and changes in axis should be sought after considering anatomical limitations. Mandibular ASO should be performed with caution in skeletal Class II patients vulnerable to airway-related problems.

Three dimensional evaluation of soft tissue after orthognathic surgery.

BACKGROUND: To evaluate the nasolabial soft tissue change three-dimensionally after orthognathic surgery, using a structured light scanner. METHODS: Thirty-two malocclusion patients, who underwent orthognathic surgery, were evaluated. CBCT and 3D facial scans were obtained before surgery and 3 months after surgery. The 3D changes in the 26 landmarks, and the relative ratio of the soft tissue movement to the bony movement, were evaluated. RESULTS: In the Le Fort I advancement patients, the nasal tip moved 17% forward, compared to the maxillary bony movement, but the nasal prominence decreased 15%. The alar width increased 4 mm after the advancement, and the width decreased 4.7 mm after Le Fort I setback. The relative ratio of the soft tissue movement to the bony movement after bilateral sagittal split osteotomy was about 66% at the Li point in the anteroposterior direction, and it was 21% in the Le Fort I advancement and 14% in Le Fort I setback at the Ls point. CONCLUSION: Alar cinch suturing may not be sufficient to overcome the effect of the maxilla advancement compressing the nasal complex. Alar width widening was prevented in Le Fort I setback. However, it is uncertain that the alar cinch suturing was solely responsible. The soft tissue around the mandible tends to accompany the bony movement more than the maxillary area. In addition, structured light scanning system proved to be a useful tool to evaluate the nasolabial soft tissue.

Three-dimensional volumetric analysis of condylar head and glenoid cavity after mandibular advancement.

The aim of this study was to assess condylar resorption, spatial change in glenoid cavity, and its risk factors after mandibular advancement by three-dimensional volumetric analysis. Subjects consisted of 30 condyles of 15 patients diagnosed with mandibular retrognathism who underwent Le Fort I and bilateral sagittal split ramus osteotomy advancement. CBCT images were taken before surgery (T0), immediately after surgery (T1), and postoperatively at 6 months (T2) and 1 year (T3). Condylar resorption was observed in 21 condyles. The posterior was the most affected region, while the anterior was the least affected. The volume of the glenoid cavity was significantly increased after surgery regardless of the presence or absence of resorption. However, the cavity recovered close to its original volume over time. At 1 year after surgery, the volume was not significantly different from the preoperative volume. Counterclockwise rotation of the proximal segment was found to be a risk factor affecting resorption based on correlation analysis. Mandibular advancement appeared to generate excessive mechanical stress on the posterior condyle, and might be responsible for the resorption. Counterclockwise rotation might have added stress to the region. Articular spatial change was transient and did not appear to be related to condyle resorption.

Positional change in mandibular condyle in facial asymmetric patients after orthognathic surgery: cone-beam computed tomography study.

BACKGROUND: We evaluated change in the mandibular condyle after orthognathic surgery using cone-beam computed tomography (CBCT) in patients with facial asymmetry. METHODS: Thirty patients with skeletal class III malocclusion and mandibular prognathism or facial asymmetry were classified into two groups according to the amount of menton deviation (MD) from the facial midline on anteroposterior (AP) cephalogram: group A (asymmetry, MD ≥ 4 mm; n = 15) and group B (symmetry, MD < 4 mm; n = 15). Position and angle of condylar heads on the axial, sagittal, and coronal views were measured within 1 month preoperatively (T0) and postoperatively (T1) and 6 months (T2) postoperatively. RESULTS: On axial view, both groups showed inward rotation of condylar heads at T1, but at T2, the change was gradually removed and the condylar head returned to its original position. At T1, both groups showed no AP condylar head changes on sagittal view, although downward movement of the condylar heads occurred. Then, at T2, the condylar heads tended to return to their original position. The change in distance between the two condylar heads showed that they had moved outward in both groups, causing an increase in the width between the two heads postoperatively. Analysis of all three-dimensional changes of the condylar head positions demonstrated statistically significant changes in the three different CBCT views in group B and no statistically significant changes in group A. CONCLUSIONS: There was no significant difference between the two groups in condylar head position. Because sagittal split ramus osteotomy can be performed without significant change in symmetrical and asymmetrical cases, it can be regarded as an effective method to stabilize the condylar head position in patients with skeletal class III malocclusion and mandibular prognathism or facial asymmetry.

Anti-inflammatory effect of polydeoxyribonucleotide on zoledronic acid-pretreated and lipopolysaccharide-stimulated RAW 264.7 cells.

Bisphosphonates are generally used as therapeutic agents for bone diseases. However, previous reports on bisphosphonates-related osteonecrosis of the jaw (BRONJ) demonstrated that inflammation triggers and worsens the disease. Recently, polydeoxynucleotide (PDRN), an A2A receptor agonist, has been suggested for the treatment of various diseases and broadly studied for its anti-inflammatory effect. The present study aimed to measure the effect of PDRN on macrophage cells treated with zoledronic acid (ZA) and lipopolysaccharide (LPS). Macrophage cells were cultured with ZA for 24 h, following which they were stimulated with LPS in the presence or absence of varying concentrations of PDRN for 24 h. The cell viability and nitric oxide (NO) production of the cells were analyzed. In addition, protein expression levels were quantified by western blotting. Cell viability was compromised and NO was overexpressed by ZA and LPS stimulation. However, under ZA and LPS stimulation cell viability was enhanced, and NO production, and inducible nitric oxide synthase, interleukin (IL)-1ß, -6, and tumor necrosis factor-α overexpression were suppressed on exposure to PDRN. A2A receptor and vascular endothelial growth factor (VEGF) expression levels increased following PDRN treatment. These results indicate that PDRN treatment of macrophages inhibits the inflammatory cytokines induced by ZA and LPS stimulation. It was hypothesized that the inflammatory cytokines were inhibited through A2A activation by PDRN. In addition, increased VEGF expression may contribute to increased vascularization and subsequently improve the pathological condition in BRONJ. As inflammation and LPS may stimulate the occurrence of BRONJ, the present study postulated that PDRN is possibly a candidate for the therapeutic management of BRONJ by decreasing inflammation and increasing vascularization.

Comparison between anterior segmental osteotomy versus conventional orthodontic treatment in root resorption: a radiographic study using cone-beam computed tomography.

BACKGROUND: Patients who received orthodontic treatment are likely to have apical root shortening. It appears that external apical root resorption results from a combination of patient-related risk factors such as genetic influences, systemic factors, and orthodontic treatment-related factors. Regarding the fact that the anterior segmental osteotomy (ASO) has been known for its possibility of complementing external apical root resorption and of buffering periodontal problems, it has been the preferred treatment. However, the studies on the efficacy of ASO in preserving the root are not sufficient. In this study, we compared the amount of root resorption between the patients who only received orthodontic treatment and the patients who received orthodontic treatment with ASO. METHODS: This study included 28 patients (the number of incisor = 198) who received orthodontic treatment with or without ASO. We categorize them into groups A and B by the type of orthodontic treatment (group A: conventional orthodontic treatment; group B: orthodontic treatment with ASO). Cone-beam computed tomographic and cephalometric evaluations were retrospectively performed on the radiographs taken for the diagnosis of the treatment before treatment and at the end of active treatment. RESULTS: In group B, root resorption itself and its rate both turned out to have significantly lower than those in group A. Also, the change of incisal angle is significantly smaller in group B than in group A. On the other hand, in group A, the change of incisal angle was positively correlated with the change of AP (anteroposterior) position. In group B, the change of incisal angle was negatively correlated with the duration of the orthodontic treatment. In group B, amount of root resorption (mm) was positively correlated with the duration of the orthodontic treatment. CONCLUSIONS: The results show lesser root resorption and shorter treatment duration with ASO than with conventional orthodontic treatment. Therefore, if the indications are accurately determined, ASO can be an effective treatment option when the amount of root resorption is expected to be high, especially in late adults.

Double Anterior Segmental Osteotomy Under Local Anesthesia for Correcting Adult Protrusion With Thin Alveolus and Ankylosed Tooth.

BACKGROUNDS: This paper describes an additional benefit in double anterior segmental osteotomy to correct severe anterior protrusion in adult patients with extremely thin mandibular alveolus and ankylosed tooth. For the optimal anterior segmental retraction, an ankylosed posterior tooth needed surgical inclination reposition. During anterior segmental osteotomy surgery under local anesthesia, additional single tooth osteotomy was performed without challenge. METHODS: For anterior segment retraction, osteotomy cuts were made by the surgeon to define a block of bone embedding 6 mandibular anterior teeth. First premolars were extracted during initial orthodontic treatment period. But the ankylosed lower left lateral incisor and lower right second premolar root which remains mesially with uprighted crown hindered further anterior segment retraction. The authors removed cortical bone around second premolar root and repositioned to be upright. Anterior segment was retracted to proper position utilizing the space gained. RESULT: Thin alveolar mandibular anterior segment retraction and the second premolar uprighting were managed effectively with additional single tooth segmental osteotomy during anterior segmental osteotomy. CONCLUSION: Double anterior segmental osteotomy can be an effective alternative to conventional orthognathic surgery in selected adult patients.

Gastrokine 1 inhibits gastric cancer cell migration and invasion by downregulating RhoA expression.

BACKGROUND: We investigated whether GKN1, a gastric tumor suppressor, contributes to the progression of gastric cancer by regulating RhoA expression. METHODS: We analyzed the expression of GKN1, RhoA, miR-185, and miR-34a in 35 gastric cancer tissues, and compared their expression with T category and TNM stage. Cell migration and invasion, as well as the expression of epithelial-to-mesenchymal transition (EMT)-related proteins, were assessed in GKN1- and RhoA small interfering RNA (siRhoA)-transfected and recombinant-GKN1-treated AGS and MKN1 gastric cancer cells. RESULTS: Expression of RhoA protein and messenger RNA (mRNA) was increased in 15 (42.9 %) and 17 (48.6 %) of 35 gastric cancer tissues respectively, and was associated with higher T category and TNM stage. GKN1 expression was significantly decreased in 27 gastric cancers (77.1 %) with a higher T category, and was inversely correlated with RhoA mRNA expression. In AGS and MKN1 cells, GKN1 expression increased miR-185 and miR-34a expression and reduced RhoA mRNA and protein expression. A positive relationship between GKN1 and miR-34a and miR-185 expression and an inverse relationship between miR-34a and RhoA expression were observed in gastric cancer tissues. Cell migration and invasiveness were markedly decreased in GKN1- and siRhoA-transfected cells. GKN1 expression and silencing of RhoA decreased the expression of the proteins Snail, Slug, and vimentin. Furthermore, miR-185 and miR-34a silencing in MKN1 cells transfected with GKN1 stimulated cell migration and invasion, and increased the expression of EMT-related proteins. CONCLUSION: Our data suggest that GKN1 may inhibit gastric cancer cell migration and invasion by downregulating RhoA expression in a miR-185- and miR-34a-dependent manner.

Single-Tooth Osteotomy Combined Wide Linear Corticotomy Under Local Anesthesia for Correcting Anterior Protrusion With Ectopically Erupted Canine.

BACKGROUNDS: This article presents the alternative surgical treatments of both anterior protrusion by carrying out retraction on mandibular anterior fragment, meanwhile applying retraction force on maxilla anterior teeth and ectopically erupted canine with using platelet-rich fibrin (PRF). METHODS: Anterior segmental osteotomy was combined with linear corticotomy under local anesthesia. The correction of right ectopic canine was achieved through 2 stages. First, dento-osseous osteotomy on palatal side was performed. Then second osteotomy with immediate manual repositioning of the canine with concomitant first premolar extraction was enhanced with PRF, which was prepared by centrifuging patient's blood, applied into buccal side of high canine during osteotomy. Mandibular retraction was accomplished by anterior segmental osteotomy. RESULTS: Single-tooth osteotomy is a more effective surgical method for ankylosed or ectopically erupted tooth in orthodontic treatment. It can reduce the total orthodontic treatment time and root resorption, 1 common complication. Significant improved bone formation was seen with the addition of PRF on noncritical size defects in the animal model. It is reasonable to think that PRF can promote bone regeneration. So early bone formation also can reduce the complication such as postoperative infection. CONCLUSIONS: As an alternative to anterior protrusion and ectopically erupted canine treatment, segmental osteotomy and corticotomy combined platelet-rich plasma can enhance orthodontic treatment outcome.

Recovery of inferior alveolar nerve injury after bilateral sagittal split ramus osteotomy (BSSRO): a retrospective study.

BACKGROUND: Bilateral sagittal split ramus osteotomy (BSSRO) is the most widely used mandibular surgical technique in orthognathic surgery and is easy to relocate the distal segments, accelerating bone repair by the large surface of bone contact. However, it can cause neurosensory dysfunction (NSD) or sensory loss by injury of the inferior alveolar nerve. The purpose of the present study was to evaluate NSD after BSSRO and modifiers at NSD recovery. METHODS: In this study, NSD characteristics after BSSRO from 2009 to 2014 at the Kyung Hee University Dental Hospital were evaluated. The pattern of sensory recovery over time was also evaluated based on factors such as field of sensory dysfunction, surgical procedure, presence of pre-operative facial asymmetry, and postoperative medications. RESULTS: Most of the patients had shown NSD immediately after orthognathic surgery. Among the 1192 sides of 596 patients, NSD was observed in 953 sides and 544 patients. Sexual predilection was shown in males (p value = 0.0062). In the asymmetric group of 132 patients, NSD was observed in 128 patients (96.97 %). In the symmetric group of 464 patients, NSD was observed in 416 patients (89.45 %); on the other hand, NSD was observed significantly higher in the asymmetric group (p = 0.025). NSD-associated factors were analyzed, and vitamin B12 may be beneficial for NSD recovery. CONCLUSIONS: There was a difference between the symmetric group and the asymmetric group in NSD recovery. Vitamin B12 can be regarded as an effective method to nerve recovery. However, a further prospective study is needed.