Low-grade myofibrosarcoma of the maxillary sinus:Two case reports

BACKGROUND Low-grade myofibroblastic sarcoma(LGMS)is an extremely rare tumor characterized by the malignant proliferation of myofibroblasts.LGMS most commonly develops in adults,predominantly in males,in the head and neck region,oral cavity,especially on the tongue,mandible,and larynx.This article presents 2 cases of LGMS localized to the maxillary sinus and provides an overview of the available literature.CASE SUMMARY Two patients with LGMS located in the maxillary sinus underwent surgery at the Department of Head and Neck Surgery.Case 1:A 46-year-old patient was admitted to the clinic with suspected LGMS recurrence in the right maxillary sinus(rT4aN0M0),with symptoms of pain in the suborbital area,watering of the right eye,thick discharge from the right nostril,and augmented facial asymmetry.After open biopsy-confirmed LGMS,the patient underwent expanded maxillectomy of the right side with immediate palate reconstruction using a microvascular skin flap harvested surgically from the middle arm.The patient qualified for adjuvant radiotherapy for the postoperative bed,with an additional margin.Currently,the patient is under 1.5 years of observation with no evidence of disease.Case 2:A 45-year-old man was admitted to our clinic with facial asymmetry,strabismus,exophthalmos,and visual impairment in the right eye.Six months earlier,the patient had undergone partial jaw resection at another hospital for fibromatosis.A contrast-enhanced computed tomography scan revealed a tumor mass in the postoperative log after an earlier procedure.An open biopsy confirmed lowgrade fibrosarcoma(rT4aN0M0).The patient qualified for an extended total right maxillectomy with orbital excision and right hemimandibulectomy with immediate microvascular reconstruction using an anterolateral thigh flap.The patient subsequently underwent adjuvant radiotherapy to the postoperative area.After 9 months,recurrence occurred in the right mandibular arch below the irradiated area.The lesion infiltrated the base of the skull,which warranted the withdrawal of radiotherapy and salvage surgery.The patient qualified for palliative chemotherapy with a regimen of doxorubicin+dacarbazine+cyclophosphamide and palliative radiotherapy for bone metastases.The patient died 26 months after surgical treatment.The cases have been assessed and compared with cases in the literature.CONCLUSION No specific diagnostic criteria or treatment strategies have been developed for LGMS.The treatment used for LGMS is the same as that used for sinonasal cancer radical tumor excision;adjuvant radiotherapy or chemoradiotherapy should also be considered.They have low malignant potential but are highly invasive,tend to recur,and metastasize to distant sites.Patients should undergo regular follow-up examinations to detect recurrence or metastasis at an early stage.Patients should be treated and observed at the highest referral centers.

Maxillary Sinus Schwannoma—A Rare Tumor with Rarer Site of Occurrence

Schwannoma or neurilemmoma is a neurogenic tumor. Around 25% - 45% cases of schwannomas occur in the head and neck, of which less than 4% occurs in the nasal cavity and the paranasal sinuses. Isolated schwannomas of the maxillary sinus appear to be extremely rare. We present one such rare case of Right Maxillary Sinus schwannoma in a 48-year-old lady with swelling in the right cheek for 3 years. Infrastructure maxillectomy of the right side was done using Weber-Fergusson approach with Dieffenbach’s modification. The patient made a good postoperative recovery. We report this case keeping in mind the rarity in occurrence of isolated maxillary schwannomas.

Sequential Fluorescent Labeling Observation of Maxillary Sinus Augmentation by a Tissue-engineered Bone Complex in Canine Model

Aim To evaluate the effects of maxillary sinus floor elevation by a tissue-engineered bone complex of β-tricalcium phosphate （β-TCP） and autologous osteoblasts in dogs. Methodology Autologous osteoblasts from adult Beagle dogs were cultured in vitro. They were further combined with β-TCP to construct the tissue-engineered bone complex. 12 cases of maxillary sinus floor elevation surgery were made bilaterally in 6 animals and randomly repaired with the following 3 groups of materials： Group A （osteoblasts/D-TCP）; Group B （β-TCP）; Group C （autogenous bone） （n=4 per group）. A polychrome sequential fluorescent labeling was performed post-operatively and the animals were sacrificed 24 weeks after operation for histological observation.Results Our results showed that autologous osteoblasts were successfully expanded and the osteoblastic phenol- types were confirmed by ALP and Alizarin red staining. The cells could attach and proliferate well on the surface of the ~3-TCP scaffold. The fluorescent and histological observation showed that the tissue-engineered bone complex had an earlier mineralization and more bone formation inside the scaffold than β-TCP along or even autologous bone. It had also maximally maintained the elevated sinus height than both control groups. Conclusion Porous 13-TCP has served as a good scaffold for autologous osteoblasts seeding. The tissue-engineered bone complex with β-TCP and autologous osteoblasts might be a better alternative to autologous bone for the clinical edentulous maxillary sinus augmentation.

Case of primary extracranial meningioma of the maxillary sinus presenting as buccal swelling associated with headache:A case report

BACKGROUND Meningiomas are benign tumors that originate from the meningothelial arachnoid cells,but they rarely develop extracranially.There is no specific surgical guideline for resecting them in the maxillary sinus,and little is known about their biological behavior and operative management.CASE SUMMARY We present a 54-year-old female patient referred to our department with a primary extracranial meningioma that presented as buccal swelling associated with headache.On clinical examination the mass was non-tender,fixed,sessile and non-pulsatile situating in the right maxillary sinus.Computed tomography scan showed a well-defined mass of 7 cm×6 cm×6 cm compressing the surrounding structures.Magnetic resonance imaging revealed a well circumscribed heterogenous lesion with necrotic center and relatively hypointense on T2-weighted imaging.Imaging studies revealed no evidence of intracranial extension and metastatic nests.Biopsy showed grade I primary extracranial with low mitotic activity.Total maxillectomy with excision of tumor and adjacent paranasal structures following reconstruction of the orbit and maxilla with tissue patch was done by the maxillofacial surgeon.The biopsy reported fibrous meningioma based on the hematoxylin and eosin section.On immunohistochemistry the tumor cells were positive for vimentin,focally positive for epithelial membrane antigen and CD99 and negative for signal transducer and activator of transcription 6.The mass was removed surgically with reconstruction,and the pathological studies confirmed the diagnosis to be an extracranial meningioma.The present study briefly reviews the current knowledge concerning the diagnosis and treatment of extracranial meningiomas in the head and neck area and offers suggestions for managing extracranial meningiomas in the paranasal sinuses.CONCLUSION To conclude,extracranial meningiomas in the paranasal sinuses may be successfully managed by surgical treatment without evident post-surgery complications.

Minimally invasive maxillary sinus augmentation with simultaneous implantation on an elderly patient:A case report

BACKGROUND In this case study,a minimally invasive transalveolar approach using platelet-rich fibrin and bone substitute with simultaneous implantation was carried out in an elderly patient.We analyzed the cone-beam computed tomography(CBCT)findings to evaluate bone regeneration.CASE SUMMARY A 65-year-old female with no contraindications for dental implants and loss of maxillary bilateral molars is described.Examination by CBCT showed the available vertical bone height in the bilateral posterior maxilla was 0.5-6.8 mm in the left and 2.8-6.5 mm in the right.The patient underwent a transalveolar approach using platelet-rich fibrin and bone substitute with simulataneous placement of an implant 10 mm in length.Six months post-surgery,the implant showed excellent osseointegration with the bone graft.Thereafter,full-ceramic crowns were fitted.Follow-up at 2 years demonstrated satisfactory prognosis.CONCLUSION Platelet-rich fibrin and bone substitute can be used to augment the maxillary sinus with a vertical bone height less than 4 mm.

Diffuse large B cell lymphoma originating from the maxillary sinus with skin metastases:A case report and review of literature

BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is the most common type of malignant lymphoma(ML),accounting for 30%-40%of cases of non-Hodgkin’s lymphoma(NHL)in adults.Primary paranasal sinus lymphoma is a rare presentation of extranodal NHL that accounts for only 0.17%of all lymphomas.ML from the maxillary sinus(MS)is a particularly rare presentation,and is thus often difficult to diagnose.We have reported the first known case of DLBCL originating from the MS with rapidly occurrent multiple skin metastasis.CASE SUMMARY An 81-year-old Japanese man visited our hospital due to continuous pain for 12 d in the left maxillary nerve area.His medical history included splenectomy due to a traffic injury,an old right cerebral infarction from when he was 74-years-old,hypertension,and type 2 diabetes mellitus.A plain head computed tomography(CT)scan revealed a 3 cm×3.1 cm×3 cm sized left MS.On day 25,left diplopia and ptosis occurred,and a follow-up CT on day 31 revealed the growth of the left MS mass.Based on an MS biopsy on day 50,we established a definitive diagnosis of DLBCL,non-germinal center B-cell-like originating from the left MS.The patient was admitted on day 62 due to rapid deterioration of his condition,and a plain CT scan revealed the further growth of the left MS mass,as well as multiple systemic metastasis,including of the skin.A skin biopsy on day 70 was found to be the same as that of the left MS mass.We notified the patient and his family of the disease,and they opted for palliative care,considering on his condition and age.The patient died on day 80.CONCLUSION This case suggests the need for careful,detailed examination,and for careful follow-up,when encountering patients presenting with a mass.

Maxillary Sinusitis of Dental Origin

We report a 53 year-old male who suffered 18 months of foul-smelling green nasal discharge, halitosis and a heavy discomfort behind his right eye. The symptoms were consistent with chronic rhinosinusitis. The patient had a right upper molar dental extraction shortly before the onset of symptoms. A radio-opaque foreign body was noted in his right maxillary sinus on CT. During surgery a tooth resembling foreign body was removed. The patient＇s symptoms completely resolved within weeks of the removal.

Treatment of traumatic globe dislocated completely into the maxillary sinus

Dear Sir, I am Dr. Bei Xu, from Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, Hunan Province, China. I want to present a rare case of the treatment of traumatic globe dislocated completely into the maxillary sinus. A 46-year-old female was admitted to emergency unit due to traffic accident, presenting disturbance of consciousness for nine hours.

Morphometric analysis of the relationships between the maxillary first molar and maxillary sinus floor

Objectives: To assess the relationships between the maxillary first molar and the maxillary sinus floor in a group of patients referred to a dental clinic. Methods: Ninety-seven patients were recruited for this study. The distances between the examined roots (mesio-buccal, disto-buccal and palatal) as well as furcations, and the sinus floor, were evaluated using cone beam computed tomography, and grouped as follows: class 0: distance = 0 mm;class 1: 0 mm < distance < 2 mm;class 2: 2 mm ≤ distance < 4 mm;class 3: 4 mm ≤ distance < 6 mm;class 4: 6 mm ≤ distance. The Spearman’s Rank Correlation coefficient was used to test the univariate associations between furca-tion-sinus floor distance and each root class. Results: The prevalence of class 0 was the highest for the palatal root (44.33%), followed in descending order by mesio-buccal (40.21%), and disto-buccal (38.14%) roots. The highest correlation coefficient was recorded when assessing the relationship between furcation-sinus floor distance and palatal root classes (rho = 0.66, p < 0.001, n = 97). Conclusions: Altogether, the results suggest that the palatal root of the maxillary first molar not only had the closest relationship with the sinus floor, but also proved to be the best predictor for the furcation-sinus floor distance. The clinician should be aware of the anatomical and morphological details of this root, especially when taking surgical decisions.

Endoscopic sinus surgery plays an essential role in systematic treatment of odontogenic maxillary sinusitis

Purpose:Odontogenic maxillary sinusitis(OMS)is frequently encountered in otorhinolaryngologists'clinical practice.Endoscopic sinus surgery(ESS)instead of surgeries in intraoral approach has been widely applied among OMS.However appropriate treatments due to the causes of the OMS as well as the outcome have been less investigated,meanwhile the inherent incidence of OMS may be still on the rise.This study was designed to conclude our systematic treatment within follow-up examination.Materials and methods:In this retrospective study patients confirmed diagnosis of OMS who had systematic follow-up examinations were analyzed.Medical histories of otorhinolaryngologists and dentists were reviewed as well as preoperative examination protocols.Result:Consecutive 29 Patients(10 women,19 men)were included.41.4%(12/29)patients experienced facial pain as the most frequent symptom.69.0%(20/29)patients admitted firstly to otorhinolaryngologists,13 patients were treated with surgical procedure while 7 patients lacking of surgical indication were transferred to dentists.31.0%(9/29)patients were advised by dentist for being suspected of maxillary sinusitis,including 7 patients suffered from sinonasal complications of dental treatment(SCDT).Conventional dental treatment(root planning,root end surgery,extraction)was the most common cause.Follow up for a mean of 15.1(ranges from 6 to 96)months showed 29 patients maintaining open maxillary ostium on endoscopic examination or improving on CT except recurrence in one patient with SCDT.Conclusion:Patients should be inspected by dentists carefully when the patient has symptoms rather than sinusitis-like symptoms,the possibility of OMS should always be considered.Dental examination can help to determine whether a maxillary sinusitis has a dental origin,periodontitis and odontogenic radicular cysts still are the most common causes comparing with iatrogenic factors.Patients treated with ESS showed better tolerance and fewer postsurgical complications.Not all patients with OMS including SDCT need definitely surgery whether ESS or intraoral approach,removing dental focus followed with antibiotics would be optimistic choice.

数字化三维重建手术治疗上颌窦牙源性影细胞癌1例

1临床资料患者,男,33岁,因鼻塞4个月于2020-05-25以“右侧上颌窦肿物、慢性鼻炎”收治入院。患者入院前4个月发现双侧鼻塞,右侧明显,鼻塞持续性,无明显流涕、头痛、面部肿胀,在当地某医院诊断为“慢性鼻炎”,予鼻喷激素及达芬霖等药物治疗,鼻塞有所好转,但仍反复发作。

Improved guided bone regeneration by combined application of unmodified, fresh autologous adipose derived regenerative cells and plasma rich in growth factors:A first-in-human case report and literature review

BACKGROUND Novel strategies are needed for improving guided bone regeneration(GBR) in oral surgery prior to implant placement, particularly in maxillary sinus augmentation(GBR-MSA) and in lateral alveolar ridge augmentation(LRA). This study tested the hypothesis that the combination of freshly isolated, unmodified autologous adipose-derived regenerative cells(UA-ADRCs), fraction 2 of plasma rich in growth factors(PRGF-2) and an osteoinductive scaffold(OIS)(UAADRC/PRGF-2/OIS) is superior to the combination of PRGF-2 and the same OIS alone(PRGF-2/OIS) in GBR-MSA/LRA.CASE SUMMARY A 79-year-old patient was treated with a bilateral external sinus lift procedure as well as a bilateral lateral alveolar ridge augmentation. GBR-MSA/LRA was performed with UA-ADRC/PRGF-2/OIS on the right side, and with PRGF-2/OIS on the left side. Biopsies were collected at 6 wk and 34 wk after GBRMSA/LRA. At the latter time point implants were placed. Radiographs(32 mo follow-up time) demonstrated excellent bone healing. No radiological or histological signs of inflammation were observed. Detailed histologic,histomorphometric, and immunohistochemical analysis of the biopsies evidenced that UA-ADRC/PRGF-2/OIS resulted in better and faster bone regeneration than PRGF-2/OIS.CONCLUSION GBR-MSA with UA-ADRCs, PRGF-2, and an OIS shows effectiveness without adverse effects.

Changes in pneumatization of the maxillary air sinuses in Korean adults following biomimetic oral appliance therapy

Objective:For the treatment of obstructive sleep apnea in adults,mandibular advancement devices(MADs)are often used.Since adults with a prognathic mandibular phenotype are at risk of developing an unfavorable facial profile,midfacial development using biomimetic oral appliance therapy might provide a suitable alternative.However,the effect of this procedure on the maxillary air sinuses is unknown;therefore,changes in sinus pneumati-zation were investigated in this study.Methods:After obtaining informed consent,16 consecutive Korean adults with midfacial hypoplasia had 3D cone-beam(CB)CT scans taken,and biomimetic upper appliances(DNA appliance■,Vivos Therapeutics,Inc.,USA)were constructed.All subjects were instructed to wear the device 12-16 h/day.Each month,examination for the progress of midfacial development was recorded.Post-treatment,a follow-up 3D CBCT scan was undertaken with no device in the patienfs mouth.Pre-and post-treatment linear and volumetric measurements were obtained using appropriate software,and compared statistically using t-tests.Results:The mean age of the sample was 25.0 yrs±8.7.The mean treatment time was 15.5 mths±5.2.Post-treatment,the transpalatal bone width increased from 35.3 mm±3.0 to 38.5 mm±2.0(P<0.001);the maxillary air sinus volume on the left side increased from 18.8 cm^(3)±6.5 to 20.0 cm^(3)±6.0(P<0.05),and from 18.5 cm^(3)±5.7 to 19.7 cm^(3)±5.8(P<0.05)on the right side.Conclusions:Biomimetic oral appliance therapy may be able to increase the maxillary air sinus volume in adults.In view of these preliminary findings,further studies on the effect of enhanced pneumatization on paranasal sinus function and sleep parameters are warranted.

A Simple Method of Managing the Alveolar Antral Artery during Sinus Lift Surgery

The alveolar antral artery resides lateral to the maxillary sinus and can lead to complications in sinus lift surgery. Traditional approaches that decrease intraoperative bleeding into the surgical field include vessel preservation using multiple bony windows or neutralizing the vessel at the surgical site. Unfortunately, these methods are technique sensitive, time intensive, and may lead to hemosinus and graft loss. The variable distance from the crest of the alveolar ridge and vessel diameter further complicates pre-operative planning. This paper discusses the anatomical features of the alveolar antral artery, techniques for clinical assessment, and current management strategies. We then describe a novel protocol to manage the alveolar antral artery in sinus lift procedures via tamponade of the vessel at a proximal site. This method is faster than those described in the literature, does not require any additional equipment or expertise, and aims to improve long-term graft predictability by decreasing the risk of sinus membrane perforation. The alveolar antral artery is an under-reported source of surgical complications and warrants further research.

Morphometric and Volumetric Evaluation of Maxillary Sinus as an Aid in Sex Identification in Forensic Odontology-A Cone-Beam Computed Tomography Study

Background:Various methods are used in forensic odontology for the purpose of sex and personal identification.Some of them include cheiloscopy,rugoscopy,mandibular measurements,and study of paranasal sinuses.In our study,we have used maxillary sinus as an aid in sex identification.For this purpose,we have evaluated the morphometric and volumetric measurements of the maxillary sinus using a 3-Dimensional imaging modality,Cone Beam Computed Tomography.Aims and Objectives:Sex and age identification are important in the process of identification of both the living and the dead.Hence,this transverse retrospective study was done to appraise the precision of the dimensions and volume of the maxillary sinus to aid in sex and age identification.Material and Methods:Eighty full Field of View(FOV)Cone-Beam Computed Tomography(CBCT)images were retrieved from the archives which were matched with age and sex.The maxillary sinuses on either side were measured mediolaterally in the axial section and supero-inferiorly in the coronal section.The volumetric analysis of the sinus was done in the sagittal section.The sex was classified using discriminant function analysis and the differences were compared using independent t-test.The differences with age were analyzed using one-way ANOVA.Results:Independent t-test was done for comparison of the sinuses between both sexes.Maxillary sinuses measurements were larger among the males both superior-inferiorly on either side(P<0.001)and mediolaterally on the right(P<0.049)showed statistically significant values.A significant correlation existed while comparing the maxillary sinus volume among both the sexes on either side(P<0.001 and<0.002 in the case of right and left respectively).On comparing the supero-inferior and mediolateral measurements and the maxillary sinus volume on either side among the various age groups,the values were statistically insignificant.Present study shows that the maxillary sinus measurements using Cone-beam computed tomography were diagnostic in the identification of sex but not in age estimation and can be used in forensic dentistry.

Nasal cavity-maxillary sinus-pterygopalatine fossa-Meckel’s cave:a preliminary anatomic study of an endoscopy-based operative approach

Objective To provide a new approach for the treatment of tumor in Meckel’s cave, by dissecting adjacent structures of the nasal cavity-maxillary sinus-pterygopalatine fossa-Meckel’s cave approach. Methods Fifteen adult cadaver heads （30 sides） were dissected and the correlated anatomic landmarks were observed, measured and analyzed in an operative route. Results The approach was divided into 3 steps： entering the maxillary sinus, the later pterygopalatine fossa and the final Meckel’s cave. Safe access to Meckel’s cave could be achieved by tracing the vidian neurovascular bundles and dissecting the quadrangular space （QS）. The distances from the nasal columella to the apertura maxillaries, the sphenopalatine foramen, and the anterior foramen of the pterygoid canal were （44.08±2.61） mm, （64.83±2.42） mm, and （70.43±2.94） mm, respectively. The angles between the horizontal plate of the palatine bone and the link from nasal columella to apertura maxillaries, between the horizontal plate of the palatine bone and the link from nasal columella to sphenopalatine foramen were （38.10±2.46）° and （26.15±2.26）°, respectively. Conclusion The endoscopic approach of transnasal maxillary sinus-pterygopalatine fossa-Meckel’s cave （ENMPA） is a safe and direct way to access Meckel＇s cave, and could be employed for the treatment of tumor in Meckel’s cave.

Intranasal endoscopic prelacrimal recess approach to maxillary sinus

Background The inferior turbinate （IT） and nasolacrimal duct （NLD） are often sacrificed while managing the diffuse lesion of maxillary sinus （MS）. We report a new approach to MS without ablation of NLD and IT. Methods This retrospective study enrolled 19 hospitalized patients （aged from 42 to 68 years） who underwent endoscopic sinus surgery between 2003 and 2008. Twelve patients had inverted papilloma （IP）, two had nasal polyps, two had Kubo＇s postoperative cyst of MS, one had recurrent bone cyst of maxilla, one had dentigerous cyst and one had bleeding of internal maxillary artery secondary to CaldwelI-Luc operation respectively. Two IP patients were excluded from this group since the follow-up time was less than 12 months. The NLD was dissected after removing the anterior bony portion of nasal lateral wall. The prelacrimal recess approach （PLRA） to MS was established when IT-NLD flap was raised medially. The flap was repositioned when MS lesion was removed. Results All the 17 patients had unilateral lesions. Ten MS IP patients were at the T3 Krouse stage. The follow-up ranged from 7 to 60 months. No recurrence was seen in 16 patients. Only one IP patient had a local recurrence in MS. All of them had no any complications. Conclusion The diffuse or severe diseases of MS may be the potential indications for PLRA.

Histologic Changes in the Sinus Membrane after Maxillary Sinus Augmentation with Simultaneous Implant Placement Using Engineered Bone Graft Material

The aim of the study was to analyze the histologic and ultrastructural changes after maxillary sinus augmentation with simultaneous implant placement using engineered bone graft material.In this study,calcium phosphate cement(CPC)scaffolds combined with goat bone marrow stromal cells(BMSCs)were used to fill goat sinus floor space after maxillary sinus floor elevation with simultaneous implant placement comparing with those not filled any grafted materials and used as controls.After a healing period of 3 months,the goat maxillary sinus membrane was examined using light microscopy and scanning electronic microscopy.The results showed that the connective tissue thickness and the epithelium thickness of mucosa were not statistically significant difference between two groups.The tissue engineered bone complex might be an ideal graft for the sinus floor elevation and have no influence on the sinus membrane under the histological and ultrastructural observation.

MANAGEMENT OF THE ORBITAL CONTENTS IN RADICAL SURGERY FOR SQUAMOUS CELL CARCINOMA OF THE MAXILLARY SINUS

We reviewed retrospectively 139 patients with squamous cell carcinoma of the maxillary sinus who were treated with planned combinations of preoperative radiotherapy and maxillectomy between 1958 and 1987. The 5-year survival rate of these patients was 30%. In 111 patients who had tumor invasion of the orbital floor 88 underwent radical surgery with orbital exenteration and 23 had their orbital contents preserved. If orbital exenteration was performed, the 5-year survival rate was 27.3% (24 / 88) and the rate of recurrence within the orbit was 12.5%. In patients with preservation of the orbital contents, the corresponding rates were 34.8% (8 / 23) and 8.6% respectively (P = 0.65). Histological study af ter maxillectomy with orbital exenteration showed that in 95% of 65 specimens (62 / 65) invasion of the orbit was limited. These tumors could be completely resected by total maxillectomy with limited removal of the periorbital tissues after preoperative radiotherapy. We conclude that after preoperative radiation, the eyeball could be safely preserved in most selected patients with maxillary sinus carcinoma invading the orbital floor.

Effect of superantigen on ion electrophysiology and permeability in rabbit maxillary sinus epithelia

Obejctive Superantigens are potent inflammatory stimuli which derive from pathogenic microbes such as bacteria, viruses and protozoa The aim of this study was to investigate the role of superantigens on the function of rabbit maxillary sinus epithelium Methods Twenty New Zealand white rabbits were divided into 4 groups Rabbit sinus mucosa was separated under a surgical microscope and mounted in Ussing chambers to record short circuit current, conductance and permeability to horseradish peroxidase (HRP) Group A was used as normal control Group B was stimulated with an injection of superantigen into the sinus for 4 hours The sinus mucosa of Group C was stimulated by the addition of tumor necrosis factor α (TNF α) into Ussing chambers Group D sinus mucosa was stimulated by superantigen after pretreatment with anti TNF α antibody Results Superantigen evoked increases in sinus epithelial cell baseline short circuit current, conductance and permeability to HRP stimulated by the addition of TNF α into Ussing chambers These were similar to results from superantigen stimulation in vivo The effect of superantigen on sinus epithelial cells could be blocked by pretreatment with anti TNF α antibody Conclusions Superantigen affected the function of sinus epithelial cells, including the capability of epithelial defensive barrier, which might be mediated by TNF α