Effects of personalized oral exercises on swallowing function among patients with oral cancer after free flap transplantation: a cluster randomized controlled trial.

Dysphagia is a common complication in patients with oral cancer who have undergone free flap transplantation. The aim of this cluster randomized controlled trial was to evaluate the effect of personalized oral exercises on swallowing function in this group of patients. Eligible patients were randomly assigned to the intervention (n = 34) or control (n = 34) group. Intervention group patients received personalized oral exercises starting on day 6 after surgery. Swallowing function was evaluated on days 6 and 15, and at 1 month postoperative using the Mann Assessment of Swallowing Ability-Oral Cancer tool (MASA-OC). On day 15 and at 1 month after surgery, the total MASA-OC score (P = 0.003, P < 0.001) and the mouth opening (P = 0.001, P < 0.001) and lip seal (both P < 0.001) item scores showed a significantly greater improvement in the intervention group than in the control group. Moreover, the changes in salivation (P < 0.001) and tongue movement (P = 0.025) scores at 1 month after surgery were significantly greater in the intervention group than in the control group. There was no significant difference between the groups in the change in tongue strength scores on day 15 or at 1 month postoperative (P = 0.476, P = 0.223). Personalized oral exercises can improve swallowing function in patients with oral cancer after free flap transplantation.

[Application of methylene blue near-infrared fluorescence imaging for oral sentinel lymph node mapping in rats].

OBJECTIVE: To explore the concentration range and penetration depth of methylene blue near-infrared fluorescence imaging, and to clarify the role of methylene blue in oral lymphatic drainage and sentinel lymph node localization, so as to lay a foundation for the potential research and application of sentinel lymph node in oral cancer. METHODS: 10% (mass fraction) methylene blue injection was diluted into 29 different concentrations with 0.9% (mass fraction) normal saline, and the concentration range of methylene blue near-infrared fluorescence imaging was determined by near-infrared fluorescence imager. The maximum penetration depth of methylene blue near-infrared fluorescence was determined by covering pigskin with different thicknesses (1, 2, 3, 4 and 5 mm) in methylene blue solution. 0.2 mL methylene blue solution was injected into the submucosal 0.5 cm at the lateral margin of tongue on one side of the rats. The near-infrared fluorescence imager was used for continuously monitoring for 3 hours. The first near-infrared fluorescence hotspot was identified as sentinel lymph node and labeled by percutaneous observation. The rats were then sacrificed and dissected in the head and neck. Near-infrared fluorescence imaging was performed again to observe whether the fluorescent tissue was consistent with the labeled fluorescent hotspot in vitro, and the presence of lymphoid tissue was confirmed by pathological examination after resection. RESULTS: Except that no fluorescence signals were detected in the blank control groups, the fluorescence intensity of methylene blue increased first and then decreased with its solution concentration decreased. When the concentration of methylene blue was diluted to the picomole level, the fluorescence signal could still be detected. The maximum penetration depth of methylene blue fluorescence was 4 mm. Methylene blue near-infrared fluorescence could be localized in oral lymphatic drainage and sentinel lymph node. The fluorescence was sustained for more than 3 hours after methylene blue injection. Methylene blue solution concentrations of 3.34 mmol/L, 6.68 mmol/L, 13.37 mmol/L and 26.74 mmol/L were selected in the rats to map sentinel lymph node by near-infrared fluorescence. CONCLUSION: Methylene blue near-infrared fluorescence has a certain penetrating ability and can transcuta-neously map the sentinel lymph node and their associated lymphatic vessels in rats, which is expected to be further applied in the study of sentinel lymph node in oral cancer.

[Application value of whole exon sequencing and immune related indicators in the precision treatment of oral squamous cell carcinoma].

OBJECTIVE: To explore the significance and feasibility of whole exon sequencing and immune related indexes in personalized precision treatment of oral squamous cell carcinoma (OSCC). METHODS: We retrospectively screened the patients who underwent surgery for oral cancer in Peking University Hospital of Stomatology and underwent genetic and immune biomarkers tests between January 2021 and June 2022. Combined with the clinicopathological characteristics of patients, potential targeted drugs and immunotherapy drugs were screened to evaluate the possibility of gene testing benefiting OSCC. The main evaluation indicators included the number of gene mutations, combined positive score (CPS), tumor mutation burden (TMB), microsatellite sequence status and human leukocyte antigen B (HLA-B) locus. Excel was used for statistical analysis. RESULTS: A total of 10 patients were enrolled and 9 were included in this study, including 6 males and 3 females, with an average age of (55.44±9.59) years. The tumor location was buccal (5 cases), tongue (3 cases) and gingival (1 case). The results of genetic testing showed that 3 (33.3%) patients had no gene mutations in the tumor tissue, 5 (55.6%) patients had unique TP53 gene mutations, and 1 (11.1%) patient had TP53 and CHEK1 mutations. However, no drugs were available for targeted therapy of the mutated genes. The genetic tumor gene testing results showed that no genetic tumor gene was found in all the patients, suggesting that OSCC had a low possibi-lity of hereditary tumor. In terms of immune efficacy related markers, CPS test results showed that 8 patients had CPS≥1. TMB detection results showed that the median value of TMB value was 0.72 mutations/Mb, and the range was 0 to 4.32 mutations/Mb. The negative and positive control results of microsatellite sequence status were consistent, indicating that all the tumor tissues detected were microsatellite stability. The results of HLA-B detection showed that only one patient had B62 gene mutation, suggesting that the B44 and B62 related genotypes of HLA-B in OSCC tissue samples were low. CONCLUSION: The present results do not support the wide application and promotion of genetic testing and immune related indexes in OSCC.

[Category of facial symmetry perception after maxillary reconstruction using anterolateral thigh flap].

OBJECTIVE: To preliminarily establish a category of facial symmetry perception after maxillary reconstruction using anterolateral thigh flap (ALTF) by the methods of stereophotogrammetry and subjective assessment. METHODS: The patients underwent maxillectomy due to neoplasms invasion, and all the maxillary defects were reconstructed using ALTF.Three-dimensional (3D) photographs were captured from the patients with a stereophotogrammatrical camera set-up.In the Geomagic software, the mirror image was created by reflecting along an arbitrary plane outside of the face.After the registration, the postoperative side on the original 3D photograph was segmented into 6 areas.The 3D change of the facial soft-tissue was measured using surface-based color map.Twenty laypeople took part in the study as observers, and they were asked to rate the 3D photographs using 5 point Likert-type scale according to their own aesthetic standard.The soft tissue asymmetry was graded according to the score.The collected data were subjected to statistical analysis using the SPSS 24.0 software. RESULTS: In the study, 44 subjects were recruited (21 males and 23 females, age range from 19 to 79 years).The soft-tissue symmetry was graded into three levels according to the subjective scores.The grade Ⅰ was basically symmetrical.The grade Ⅱ was slightly asymmetrical.The grade Ⅲ was obviously asymmetrical.Statistically significant differences were found in the suborbital (P < 0.05) and zygomatic (P < 0.05) areas when comparing all grades of soft-tissue asymmetry, and in the buccal (P < 0.05) and superiolabial (P < 0.05) areas when comparing grades Ⅰ and Ⅲ.The extent of maxillary defect had significant impact on the symmetry of the midface soft-tissue after maxillary reconstruction. CONCLUSION: Varying extent maxillectomy would result in varying degrees of asymmetry, and cause different grades of symmetry perception even if they had been reconstructed using ALTF.The higher the grade, the worse the symmetry of facial soft-tissue.Suborbital and zygomatic areas were important aesthetic units that affected the facial symmetry perception, followed by buccal and superiolabial areas.The clinicians should pay attention to the soft-tissue support in these areas when reconstructing the maxillary defect, especially large defect with orbital floor involved.

Bone resorption after maxillary reconstruction with the vascularized free iliac flap.

The aim of this study was to evaluate the resorption of the iliac bone after maxillary reconstruction with a vascularized free iliac flap. Twenty-seven patients with maxillary defects who underwent maxillary reconstruction with the vascularized free iliac flap between January 2017 and January 2021 were included. Computed tomography (CT) images taken at 1 week, approximately 6 months, and 1 year after the surgery were used for evaluation. The total iliac bone thickness and height, cortical bone thickness, and cancellous bone density were measured in the CT images. Compared with 1 week after the surgery, the total thickness and height of the iliac bone were reduced significantly 1 year after the surgery, and the cortical bone thickness and cancellous bone density were reduced significantly at 6 months and 1 year after the surgery. Compared with 6 months after the surgery, cancellous bone density was reduced significantly 1 year after the surgery. In conclusion, during the first year after maxillary reconstruction with a vascularized free iliac flap, there was significant resorption of iliac bone, including the total iliac bone thickness and height, the cortical bone thickness, and the cancellous bone density.

Accurate occlusion-driven maxillary reconstruction with deep circumflex iliac artery flap using computer-assisted techniques and intraoral anastomosis: a case series.

The aim of this study was to evaluate the feasibility and accuracy of occlusion-driven maxillary reconstruction with the deep circumflex iliac artery (DCIA) flap, using computer-assisted design and manufacturing (CAD/CAM) technology and intraoral anastomosis. The data of 11 patients who underwent occlusion-driven maxillary reconstruction with this method between December 2018 and December 2020 in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology were reviewed retrospectively. Postoperative complications and functional and aesthetic outcomes were recorded. The accuracy of the postoperative restoration was assessed using Geomagic Control 2014. Reconstruction was successful in nine patients; all were satisfied with their aesthetic and functional outcomes. One patient underwent extraoral anastomosis after failure of intraoral anastomosis. In another patient, the DCIA flap had to be removed after the operation because of flap failure. Among the 10 patients with DCIA flap success, colour map analysis showed a mean deviation of 0.40 ± 0.08 mm between the preoperative and postoperative craniomaxillary models. Thus, occlusion-driven maxillary reconstruction with the DCIA flap, using CAD/CAM technology and intraoral anastomosis, appears to be a feasible and accurate method for the repair of maxillary defects.

Preoperative oral carbohydrates in elderly patients undergoing free flap surgery for oral cancer: randomized controlled trial.

The aim of this study was to evaluate the safety of carbohydrate intake 2 hours before surgery in elderly patients undergoing free flap surgery for oral cancer. Elderly patients undergoing free flap surgery between September 2019 and January 2021 were randomly divided into control (n = 43) and intervention (n = 43) groups. Control group patients fasted for 6 hours and were forbidden from drinking water for 4 hours before surgery. Intervention group patients fasted for 6 hours and were forbidden from drinking after the oral administration of 5 ml/kg carbohydrate (≤400 ml) 2 hours before surgery. The main outcome measures were aspiration, fasting blood glucose level, insulin concentration, insulin resistance index (fasting at admission, prior to anaesthesia induction, immediately after surgery, and at 6 a.m. on postoperative days 1 and 2), and comfort before and after surgery. No aspiration occurred in any of the patients during anaesthesia. There were significant differences in fasting blood glucose, insulin concentration, and insulin resistance index between the control and intervention groups prior to anaesthesia induction, immediately after surgery, and on day 1 after surgery (P < 0.01). Thirst (P = 0.001) and hunger (P = 0.003) differed significantly between the two groups prior to anaesthesia induction. The intake of oral carbohydrate 2 hours before surgery was both safe and effective for elderly patients with oral cancer undergoing free flap surgery and could relieve the physiological stress response.

[Postoperative position change of fibular bone after reconstruction of maxillary defect using free fibular flap].

OBJECTIVE: To investigate the position change of the fibular bone after maxillary reconstruction by free fibular flap and to analyze the factors affecting the position change. METHODS: Patients who underwent maxillary reconstruction by free fibular flap in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from November 2012 to November 2016 were enrolled in this study. CT scans 1 week and 1 year postoperatively were collected and stored in DICOM format. The ProPlan CMF software was used to reconstruct the CT scans and separate the maxilla and each segment of the fibular flap. The Geomagic Control software was used to measure the long axis direction vector of each fibular segment. And the position change direction was recorded. The patients were divided into groups according to the use of the fibula or titanium plate to reconstruct the zygomaticmaxillary buttress. RESULTS: A total of 32 patients were enrolled. Among them, 21 were in the titanium plate group and 11 in the fibula bone group. The angle between the long axis of the fibular segment and the X axis in the X-Y plane was 95.65°±53.49° and 95.53°±52.77°, 1 week and 1 year postoperatively, and there was no statistical difference (P>0.05). The angle between the long axis of the fibular segment and the X axis in the X-Z plane was 96.88°±69.76° and 95.33°±67.42°, respectively, with statistical difference (P=0.0497). The angular changes of the long axis of the fibular segment in the titanium plate group and the fibular bone group were 3.23°±3.93° and 1.94°±1.78°, respectively, and the angular changes in the X-Z plane were 6.02°±9.89° and 3.27°±2.31°, respectively. There was no significant difference between the groups (P>0.05). The long axis changes of the fibular segment in the X-Y plane for reconstruction of the anterior alveolar, posterior alveolar, and buttress were 3.13°±3.78°, 2.56°±3.17°, and 5.51°±4.39°, respectively. There was a statistical difference (P = 0.023) between the posterior and buttress. In the X-Z plane, theses were 4.94°±4.75°, 5.26°±10.25°, 6.69°±6.52°, respectively. There was no statistical difference among the three groups (P>0.05). The main positional deviation directions of the titanium plate group and the fibular bone group were interior and superior sides, and there was no statistical difference between the two groups (P>0.05). CONCLUSION: One year postoperatively, the position of the free fibular flap was changed compared with 1 week postoperatively. The position of the free fibular flap was mainly changed to the interior and superior sides.

[Measurement of the weight and volume of submandibular gland in vitro].

OBJECTIVE: To measure the weight and volume of normal submandibular gland by in vitro detection of glandular body, to compare with the measurement values of CT volume rendering to evaluate the consistency of the two methods, and to explore the related factors affecting the weight and volume of the submandibular gland. METHODS: The patients who underwent neck dissection due to oral cancer and were confirmed with normal submandibular gland by postoperative histopathology in Peking University School and Hospital of Stomatology from May 2019 to January 2020 were collected in this study and divi-ded into 4 groups according to the age standards raised by the Society of Geriatrics Chinese Medical Association and WHO (2000) age standards. The submandibular gland was carefully dissected along with the capsule immediately after neck dissection. The weight and volume of submandibular gland were accurately measured by an integrated aseptic measuring device. The volume of submandibular gland was measured by CT volume rendering before operation and the consistency of the two methods was evaluated. The 95% confidence interval of the weight and volume of submandibular gland in the different groups of Chinese people, which were divided by gender and age, were calculated, and the correlation with age, gender, height, weight, body mass index (BMI) and other factors was analyzed. RESULTS: The weight and vo-lume of submandibular gland were measured in 220 subjects. The average weight and volume of submandibular gland were (11.69±2.45) g and (11.55±2.41) cm3 respectively. The volume of submandibular gland measured by CT volume rendering ranged from 70% to 82% of that measured by in vitro detection of glandular body, and the correlation coefficient between the two methods was 0.976 (P < 0.05). The gender difference of weight and volume of submandibular gland existed in the groups of youth, middle-aged, young elderly and elderly groups, the values of males were obviously higher than those of females (P < 0.05). There was no gender difference of weight and volume of submandibular gland in the adolescent group (P > 0.05). The weight and volume of submandibular gland had a strong positive correlation with body height (P < 0.05), a weak positive correlation with body weight (P < 0.05), and no correlation with BMI (P > 0.05). The female's weight and volume of submandibular gland in the young elderly and elderly groups were significantly lower than those in the other three groups (P < 0.05). CONCLUSION: The normal reference range of the weight and volume of submandibular gland in vitro were established in different age and gender groups of Chinese people. The volume of submandibular gland mea-sured by CT volume rendering was 70%-82% of that measured by in vitro detection of glandular body. The results of the two methods had a high degree of consistency. The weight and volume of submandibular gland were related to age, gender, body height and body weight.

[Delayed diagnosis of oral squamous cell neoplasms at different sites].

OBJECTIVE: To investigate the diagnostic delay of patients with oral squamous cell carcinoma by self-designed questionnaire to find out the significant influencing factors, so as to identify the influencing factors of the patient's delay and the risk of oral cancer. METHODS: A total of 514 patients with primary oral squamous cell carcinoma were enrolled at Peking University School and Hospital of Stomatology from January 2014 to April 2016, including 334 men and 180 women, with a male to female ratio of 1.85:1. The youngest participant was 21 years old, with a maximum of 89 years and a median age of 57.6 years. The position of the disease according to International Classification of Diseases-10 (ICD-10) was divided into lip, buccal, gingival, retromolar, palate, floor of the mouth, tongue, and oropharynx. The age group is divided into 10 years. The level of education was divided into illiteracy, primary education level and advanced education level. Body mass index (BMI) was divided into three levels by 18 kg/m2 and 25 kg/m2. Visual analog scale (VAS) method was to evaluate the patient's preoperative pain. At the same time, the patients were examined by detailed questionnaire to understand the delay factors and delay characteristics, and use SPSS 18.0 software, analysis of variance and chi-square test to explore correlation. RESULTS: Among all patients, the proportion of patients developed in the tongue was the highest (43.3%). Delay was defined by a span of three months or longer from the onset of symptoms until treatment. The delays to diagnosis according to location were as follows (in months and in descending order): lip (6.1 months), buccal (4.1 months), floor of the mouth (3.9 months), tongue (3.6 months), oropharyngeal (2.9 months), retromolar (2.7 months), palatine (2.4 months), and gingival (2.4 months). Different sites and delayed diagnosis were statistically significant (P=0.048). There were no statistically significant differences in gender, education, pain, smoking, drinking and VAS score. CONCLUSION: The study has found that tumor positions and delay have a significant correlation. The position of the tumor is an obvious factor associated with the findings. The lip is the most likely to delay the diagnosis of oral positions. For the lip of the lesion, more than three months' obvious mass is recommended for timely treatment, while at admission, physicians should take the appropriate diagnostic method as soon as possible.

[Role and mechanism of muscarinic acetylcholine receptor in the regulation of submandibular gland secretion].

Muscarinic acetylcholine receptors (mAChRs), including M1-M5 subtypes, are classic receptors in regulating water, ion, and solute transport in salivary gland. Our work focuses on the studies on the expression pattern and function of mAChR in the submandibular gland (SMG), and the underlying mechanism involved in the mAChR-regulated secretion, together with the effect of parasympathectomy on the salivary secretion. Microvascular autotransplantation of SMG into the temporal fossa provides a continuous and endogenous source of fluids, and is currently an effective method for treating severe keratoconjunctivitis sicca. By using RT-PCR, Western blotting, and immunofluorescence, our data demonstrated that the expression of M1 and M3 subtypes were decreased in latent period in rabbit SMG autotransplantation model, whereas carbachol stimulation promoted the salivary secretion, as well as M1 and M3 expressions. By contrast, mAChRs were hypersensitive in epiphora SMGs, whereas atropine gel and botulinum toxin A application significantly inhibited the hypersecretion in both animal models and patients. Furthermore, the possible intracellular signal molecules involved in the mAChR-modulated salivary secretion were explored. Activation of mAChR upregulated the expression of aquaporin 5 (AQP5), the main transporter that mediated water secretion through transcellular pathway, and led to AQP5 trafficking from lipid rafts to non-lipid microdomain. Extracellular signal-regulated kinase 1/2 (ERK1/2) was involved in the mAChR-regulated AQP5 content. mAChR activation also modulated the expression, distribution, and function of tight junction proteins, and increased paracellular permeability. ERK1/2/ß-arrestin2/clathrin/ubiquitin signaling pathway was responsible for the mAChR-regulated downregulation of tight junction molecule claudin-4. Cytoskeleton filamentous actin (F-actin) was also involved in the distribution and barrier function of epithelial tight junctions. Besides, endothelial tight junctions were opened by mAChR agonist-evoked salivation in the mice. Furthermore, parasympathetic denervation increased resting salivary secretion in the long terminrats and minipigs. Taken together, our work demonstrated that mAChR regulated saliva secretion via transcellular and paracellular pathways in SMG epithelium as well as tight junction opening in SMG endothelium. Modulation of mAChR might be a promising strategy to ameliorate SMG dysfunction.

Cortical bone resorption of fibular bone after maxillary reconstruction with a vascularized fibula free flap: a computed tomography imaging study.

This study was performed to evaluate the cortical bone resorption of fibular bone after maxillary reconstruction with a fibula free flap. A total of 35 patients with maxillary defects that were repaired using a fibula flap (62 fibula segments) between January 2011 and January 2016 were enrolled. Computed tomography (CT) images taken 1 week and 1 year postoperative were used to evaluate cortical bone resorption. The 62 fibula segments were measured on four different surfaces in the CT images. At 1 week, the thickness of the cortical bone was 2.57 ± 0.58 mm, 2.72 ± 0.46 mm, 3.84 ± 0.98 mm, and 4.36 ± 0.90 mm for the exterior, interior, superior, and inferior sides, respectively. At approximately 1 year, the cortical bone thickness was significantly reduced to 2.00 ± 0.65 mm (P < 0.01), 2.25 ± 0.60 mm (P < 0.01), 3.37 ± 0.90 mm (P < 0.01), and 2.96 ± 0.84 mm (P < 0.01) for the exterior, interior, superior, and inferior sides, respectively. The cortical bone thickness of fibular bone is significantly reduced 1 year after the restoration of maxillary defects with a fibula free flap, most significantly on the inferior side.

Comparison of the subjective satisfaction of the donor site morbidity: Free radial forearm flap versus anterolateral thigh flap for reconstruction in tongue cancer patients.

BACKGROUND: The purpose of the study was to compare the differences of the subjective satisfaction of the donor site morbidity between the free radial forearm flap (FRFF) and anterolateral thigh flap (ALTF) for tongue reconstruction. MATERIAL AND METHODS: One hundred and nineteen patients underwent FRFF or ALTF reconstruction were retrospectively evaluated by a standardized self-established donor site morbidity questionnaire which included 5 domains, sensibility, movement disabilities, cosmetics, social activities and general impacts on the quality of life. RESULTS: The Cronbach's coefficient alpha of the questionnaire was 0.707. The exploratory factor analysis revealed that the 5 items of the questionnaire might load onto two distinct subscales. Patients with ALTF had higher scores in the sensibility, cosmetics and the composite score (P < 0.05). No significant differences were found in the movement disabilities, social activities and general impacts on the quality of life between the two groups (P > 0.05). CONCLUSIONS: ALTF has the advantage of better results of donor site morbidity, such as sensibility and cosmetics, over FRFF.

Factors influencing the long-term results of autologous microvascular submandibular gland transplantation for severe dry eye disease.

We assessed long-term outcomes of autologous microvascular submandibular gland (SMG) transplantation for severe dry eye disease and investigated factors influencing long-term results. From August 1999 to January 2015, 185 patients (200 eyes) with severe dry eye received SMG transplantation. Subjective assessments and ophthalmologic evaluations were performed before and after transplantation. Follow-up results showed successful transplantation in 180 of 200 eyes (success rate: 90%), resulting in marked symptomatic relief of xerophthalmia. Surgery failed due to vascular thrombosis (15 glands) and duct obstruction (5 glands). Follow-up data were available for 163 eyes. Epiphora occurred in 98 (60.1%) eyes and was effectively managed by surgical reduction of graft, topical atropine gel and botulinum toxin injection. Wharton's duct obstruction occurred in 16 (10.6%) eyes and was treated by duct reconstruction. Subjective satisfaction was achieved in 143 (87.7%) eyes. Mean score of fluorescent staining reduced from 11.25±1.42 to 7.25±3.37. Postoperative best-corrected visual acuity improved in 85 (56.3%) eyes. Our clinical experience proved that SMG transplantation is effective and grants long-term improvement in severe dry eye. Secretory function of transplanted SMGs remains active and stable. Blood vessel thrombosis, Wharton's duct obstruction, and epiphora are primary factors influencing results.

Botulinum toxin A treatment of epiphora secondary to autologous submandibular gland transplantation.

The aim of this study was to explore whether botulinum toxin A (BTXA) injection treats epiphora secondary to submandibular gland (SMG) transplantation for severe keratoconjunctivitis sicca. Fifteen patients with epiphora after SMG transplantation were separated to three groups, and received 15U, 20U and 25U BTXA injection in the transplanted SMG, respectively. Secretion of transplanted SMG was assessed subjectively by visual analogue scale (VAS) regarding epiphora, and objectively by Schirmer test. There were no significant differences in the 15-U BTXA group regarding the values of the VAS on epihora before and 1 month after BTXA injection. While in 20-U group and 25-U group, the values of VAS on epihora decreased significantly after BTXA injection, and lasted for 6months. Under resting conditions, the secretion of transplanted SMG decreased 64.4%, 73.0% and 78.0% in 15-U, 20-U and 25-U groups, respectively (P<0.01), in 1month after BTXA injection; significant secretion decreasing lasted 3months only in the 25-U BTXA group. BTXA injection can decrease the secretion of transplanted SMG significantly, relieving the symptoms of epiphora; 25U BTXA is a suitable dose to treat 'opportunistic epiphora' after SMG transplantation.

Non-vascularised fibular bone graft after vascular crisis: compensation for the failure of vascularised fibular free flaps.

After reconstruction of a segmental mandibular defect with a fibular free flap, a vascular crisis can be detected clinically and a "no-flow" phenomenon found during re-exploration. Traditional methods used to solve this include removal of the failed flap and delayed mandibular reconstruction, or restoration of the defect with a functional reconstruction plate or contralateral fibular free flap. Our aim therefore was to investigate under what circumstances it is feasible to use a non-vascularised fibular bone graft (NVFB) as a free bone graft after the failure of a vascularised fibular free flap. From 1 January 2010-31 December 2014, 10 patients who had NVFB after failure of a fibular free flap were included in the study. All patients were treated at the Peking University School and Hospital of Stomatology. NVFB were preserved successfully without infection in all 10 cases, and follow-up imaging showed that it had incorporated well with the residual mandible, the basic function and facial aesthetics of which were maintained. In conclusion we have identified that by precise selection of patients, detailed preoperative planning, and meticulous postoperative care, NVFB can be used as a "rescue" technique after failure of a fibular free flap, and can successfully restore the segmental mandibular defect and facial contour.

Single layer centrifugation improves the quality of frozen-thawed sperm of giant panda (Ailuropoda melanoleuca).

The reproductive capacity of captive giant pandas is poor and sperm cryopreservation is necessary for the reproduction and conservation of this species. Cryopreservation, however, leads to a significant decrease in sperm quality, including sperm motility, acrosome integrity and DNA integrity. In the present study, a method was developed based on colloid single layer centrifugation that could significantly improve frozen-thawed sperm quality. Two colloids were compared for post-thaw giant panda sperm preparation; the sperm samples had greater total motility (Colloid 1: 44.5 ±â€¯16.0%, Colloid 2: 42.4 ±â€¯10.1% compared with Control: 25.4 ±â€¯8.4%, P < 0.05), linear velocity (Colloid 1: 17.2 ±â€¯8.3 µm/s; Colloid 2: 19.0 ±â€¯9.0 µm/s compared with Control: 6.6 ±â€¯1.7 µm/s, P < 0.05) and membrane integrity (Colloid: 46.9 ±â€¯13.2%; Colloid 2: 54.3 ±â€¯5.7% compared with Control: 36.0 ±â€¯9.1%; P < 0.05). This method could be a useful tool to enable the use of poor quality sperm samples and benefit this population by using available genetic material.

[A 20-year study on microvascular autologous transplantation of submandibular gland for treatment of severe dry eye].

Severe dry eye is a refractory ophthalmologic disease. Our multidisciplinary research group treated severe dry eye by microvascular autologous transplantation of submandibular gland (SMG) during the past 20 years. The SMG, with its blood vessels and Wharton's duct, was harvested from the submandibular triangle and transferred to the temporal area. The blood vessels in the SMG were anastomosed with the temporal blood vessels using a microsurgical technique. Then, the distal end of Wharton's duct was sutured to form an opening in the upper lateral conjunctival fold. The tear was replaced by the secretion of the transplanted SMG to lubricate the ocular surface. In our study, the surgical techniques of blood vessel management were continuously modified to increase the survival rate of the transplanted SMG. A novel surgical modality of partial transplantation of SMG was established to prevent postoperative epiphora. A clinical study with the largest case number in the world was conducted and the effectiveness of transplantation of SMG for severe dry eye was fully confirmed. In order to resolve two main clinical problems including ductal obstruction resulted from low secretion rate during the latent period, and epiphora due to over secretion of the transplanted SMG in the later term of transplantation, the regulation of the secretion mechanism of the normal and transplanted SMG were investigated. New opinions on mechanisms of saliva secretion were provided. Based on the priniciple of translational medicine, the results of related basic research were applied in the clinic. The clinical guidelines for secretion regulation of transplanted SMG were established. A concept of chronic obstructive sialadenitis of transplanted SMG was provided and its diagnostic criteria, diagnostic technique of sialography, and therapeutic regimen were established. As a result, the surgical success rate was obviously elevated, the surgical complications were decreased, and life quality of the patients was greatly improved.

Differential diagnosis of IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis.

Our aim was to differentiate IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis by analysing clinical, radiographic, and pathological features. Fifty-five patients, 50, and 50 were enrolled, respectively and their baseline characteristics and serological, sialographic, and pathological findings compared. The male:female ratio for IgG4-related sialadenitis was 1:1.2 for primary Sjögren syndrome 1:15.7, and for chronic obstructive submandibular sialadenitis1:0.92. Numbers with enlarged salivary glands were 55, 16, and 50; with xerostomia 26, 48, and 0; with a history of allergy 26, 4, and 6, and with coexisting systemic disease 12, 19, and 0 (p=0.14). Mean (SD) serum IgG4 concentrations were 109.1 (97.9), 4.9. (1.9) g/L, and 5.3 (1.6) g/L, p<0.001 in all cases. Sialography showed enlargement of the gland, dilatation of the duct, and slightly decreased secretory function in IgG4-related disease; obvious sialectasia and decreased secretory function in Sjögren syndrome; and dilatation of Wharton's duct and filling defects in obstructive sialadenitis. Histopathological examination showed lymphoplasmacytic infiltration with storiform fibrosis, lymphoplasmacytic inflammation and lymphoepithelial lesions, and dilatation of the duct with epithelial metaplasia in the three groups, respectively. The number of IgG4-positive plasma cells was 123 (45)/HPF, 8 (3)/HPF, and 5 (4)/HPF, while the IgG4-/IgG-positive cell ratio was 71.7 (13.9)%, 4.6 (2.5)%, 18.9 (19.7)%, respectively (p<0.001). The three conditions have different clinical, radiographic, and pathological features that provide important clues to the differential diagnosis. Serological and histological tests are important, and comprehensive consideration is necessary.

Partial sialoadenectomy for the treatment of benign tumours in the submandibular gland.

The conventional treatment for benign tumours arising in the submandibular gland (SMG) has always involved whole gland excision with the tumour. In light of developments in parotid gland functional surgery, this prospective study was performed to evaluate the effectiveness and safety of partial sialoadenectomy (PS) for benign tumours in comparison with conventional total sialoadenectomy (TS). Thirty-one consecutive patients with a preoperative diagnosis of benign tumour in the SMG were included in the study from December 2008 to December 2010. Eleven patients were treated with PS and 20 patients underwent conventional TS. Salivary gland function and surgery-related complications were assessed. No difference in resting saliva flow was found between the two groups before the operation, while this was significantly higher in the PS group than in the TS group at 1 year after surgery (P=0.009). With regard to complications, there was less deformity in facial appearance in the PS group. There was no recurrence in any of the 31 patients during the follow-up period (range 41-82 months). It is believed that this modification to SMG surgery is consistent with the idea of functional and minimal invasive salivary gland surgery. This technique represents a good choice for the management of benign tumours of the SMG for appropriately selected cases.