Diagnostic value of a novel salivary gland ultrasound scoring system in IgG4-related sialadenitis.

OBJECTIVES: To develop a novel ultrasound scoring system for the major salivary glands in patients with immunoglobulin G4-related sialadenitis (IgG4-RS) and assess its diagnostic value in a multicenter cohort of Chinese patients. METHODS: Twenty clinicians (rheumatologists, stomatologists, and radiologists) participated. The study was conducted in four steps: (1) defining the ultrasonography (US) elements, (2) developing a novel ultrasound scoring system for US of the salivary glands, (3) evaluation of inter- and intra-reader reliabilities using the new ultrasound scoring system, and (4) assessing the diagnostic value of this novel ultrasound scoring system in IgG4-RS patients in a Chinese multicenter cohort. RESULTS: A novel ultrasound scoring system for the salivary glands was developed, with total scores ranging from 0 to 34. The inter- and intra-reader reliabilities of the ultrasound scoring system were excellent (0.972 and 0.940, respectively). A total of 470 people were recruited in this study; 187 patients were diagnosed with IgG4-RS, and the remaining 283 people were diagnosed with non-IgG4-RS. Patients with IgG4-RS had significantly higher US scores than the non-IgG4-RS group (mean US score=16 vs. 4, P < 0.001). The calculated area under the curve (AUC) for the total US score was 0.852 (95% CI: 0.814-0.891). The total US scores≥9 showed a sensitivity of 75.4% and a specificity of 91.9%. Association analysis showed a positive correlation between total US scores and serum IgG4 levels and hypocomplementemia (r=0.221, r=0.349; P = 0.002) and a negative correlation between total US scores and serum C3 and C4 levels (r=-0.210, r=-0.303; P = 0.005, P < 0.001). CONCLUSIONS: A novel semiquantitative ultrasound scoring system for patients with IgG4-RS was developed, with good diagnostic performance. The inter- and intra-reader reliabilities were excellent. US scores were correlated with IgG4, C3, and C4 levels and hypocomplementemia.

Classification of the Root Position of the Maxillary Central Incisors and its Clinical Significance in Immediate Implant Placement.

PURPOSE: The aim was to classify the relationship of the sagittal root positions of the maxillary central incisor to alveolar bone using cone beam computed tomography (CBCT). METHODS: CBCT images of 934 maxillary central incisors were retrospectively reviewed included 542 men and 392 women. The sagittal root position in the alveolar bone was classified as buccal, middle, or palatal. The sagittal buccal type was further classified into 3 subtypes: I, II, and III. RESULTS: The root position type was buccal in 95.4% of the 934 incisors, middle in 4.4%, and palatal in 0.2%. In the buccal type, 47.5%, 44.2%, and 8.3% were subtypes I, II, and III, respectively. There was no significant difference in the major and subtypes of root position between the male and female subjects (both P > 0.05). CONCLUSIONS: In Chinese adults, the predominant type of sagittal root position of the maxillary central incisor is buccal. This classification system is useful in planning the implant site for immediate placement in the maxillary esthetic zone.

[Sialoendoscopy-assisted sialolithectomy for large parotid stones].

OBJECTIVE: To explore the clinical application of endoscope-assisted operative retrieval of large parotid stones as a minimally invasive alternative. METHODS: From January 2010 to April 2013, 6 patients (male: 5, female: 1, age from 30-62 years, and median age: 49.5 years)suffering from recurred swelling of parotid gland due to sialoliths were treated by endoscope-assisted parotid surgery in Peking University School and Hospital of Stomatology. All of the patients underwent clinical, ultrasonographic and cone-beam CT (CBCT) examinations to get the detailed information of the number, location and size of stones, which was recorded in the medical records. endoscope-assisted parotid surgery was performed under general anesthesia in all the 6 cases after the failure of basket or forcep retrieval firstly. During the operation, sialoendoscope was used to locate the stone exactly and then the calculus was exposed through a pre-auricular approach and released by incising the duct. The postoperative complications were recorded and observed during the follow-up periods. RESULTS: Preoperative radiological examinations showed that all of the sialoliths were near the hilum of parotid gland ducts in the 6 cases, which were 5-9 mm in diameter. All of the stones were removed successfully by endoscope-assisted operative retrieval. The incisions healed smoothly in all the 6 cases. There were no cases of facial nerve weakness, infection or salivary fistula. After a mean follow-up of 19 months (ranging from 6-36 months), 5 patients remained asymptomatic and 1 patient had mild obstructed or infective symptoms. The final results were satisfied. CONCLUSION: It is suggested that endoscope-assisted operative retrieval is a viable minimally invasive alternative to remove the large or recalcitrant parotid stones with a high successful rate and low complications.

Sialoendoscopy-assisted sialolithectomy for submandibular hilar calculi.

PURPOSE: To assess the clinical effects of endoscopy-assisted sialolithectomy for submandibular hilar calculi. MATERIALS AND METHODS: The present study was undertaken in 70 patients with symptomatic stones in the hilum of submandibular glands who underwent endoscopy-assisted sialolithectomy from December 2005 through March 2011 in the Peking University School and Hospital of Stomatology. The operative data were analyzed retrospectively. All patients were followed periodically postoperatively. Submandibular gland function was investigated by postoperative symptoms, clinical examinations, sialography, and scintigraphy. RESULTS: Submandibular stones were successfully removed in 65 patients, with a success rate of 92.9%. Temporary lingual nerve injury occurred in 1 patient. Two patients developed ranulae and underwent an uneventful sublingual gland excision. During a mean follow-up of 23 months (range, 6 to 55 mo), 52 of 65 patients were symptom free, whereas 11 patients complained of occasional swelling of the affected gland at mealtimes and 2 patients developed a recurrent stone. Thirty patients underwent postoperative sialography. The sialographic appearances included 4 types: 1) approximately normal; 2) the main duct was significantly dilated at the hilum, but no persistent contrast was seen on the functional film; 3) the main duct was significantly dilated in the hilar region, and persistent contrast was seen at the dilated hilum of the functional film; 4) the main duct was dilated or strictured, and persistent contrast was seen on the functional film. Three of the 4 patients who underwent scintigraphy exhibited good function. CONCLUSIONS: Sialoendoscopy-assisted sialolithectomy is a safe and effective gland-preservation technique for patients with hilar stones of the Wharton's duct.

Tooth lengths of the permanent upper incisors in patients with cleft lip and palate determined with cone beam computed tomography.

Objective : To measure the tooth lengths of fully developed permanent upper incisors and to qualitatively evaluate the root shapes of the incisors in patients with cleft lip and palate (CLP). Design : Cross-sectional, noninterventional, case-control imaging study. Setting : Hospital and Stomatology Unit of Peking University, Beijing, China (institutional tertiary care). Participants : Sixty consecutive nonsyndromic CLP patients (including 40 unilateral [UCLP] and 20 bilateral [BCLP]), and 53 age- and sex-matched controls were selected for this study. Main Outcome Measure : Crown heights and root lengths of permanent upper incisors were measured from cone beam computed tomography scans, and the root shapes of upper incisors were evaluated. Results : Compared with controls, the crown heights of upper incisors in CLP patients were reduced by 9.7% to 22.5% (p < .05), and the root lengths were reduced by 15.8% to 31.7% (p < .05). BCLP patients had greater reductions than the UCLP cases (p < .05). There were no significant differences between incisors and their antimeres in controls and BCLP patients. However, measurements on the cleft side in UCLP patients were lower than those of the noncleft side (p < .05). The prevalence of atypical root shape was higher in CLP than in the control group (p  =  .002); of these, 83.3% (30/36) occurred in central incisors near the cleft. Conclusion : The permanent upper incisors in nonsyndromic CLP patients are underdeveloped. Incisor developmental deficiency was greater in teeth adjacent to the cleft.

Detection accuracy of proximal caries by phosphor plate and cone-beam computerized tomography images scanned with different resolutions.

This study was carried out to assess whether the spatial resolution has an impact on the detection accuracy of proximal caries in flat panel CBCT (cone beam computerized tomography) images and if the detection accuracy can be improved by flat panel CBCT images scanned with high spatial resolution when compared to digital intraoral images. The CBCT test images of 45 non-restored human permanent teeth were respectively scanned with the ProMax 3D and the DCT Pro scanners at different resolutions. Digital images were obtained with a phosphor plate imaging system Digora Optime. Eight observers evaluated all the test images for carious lesion within the 90 proximal surfaces. With the histological examination serving as the reference standard, observer performances were evaluated by receiver operating characteristic (ROC) curves. The areas under the ROC curves were analyzed with two-way analysis of variance. No significant differences were found among the CBCT images and between CBCT and digital images when only proximal enamel caries was detected (p = 0.989). With respect to the detection of proximal dentinal caries, significant difference was found between CBCT and digital images (p < 0.001) but not among CBCT images. The spatial resolution did not have an impact on the detection accuracy of proximal caries in flat panel CBCT images. The flat panel CBCT images scanned with high spatial resolution did not improve the detection accuracy of proximal enamel caries compared to digital intraoral images. CBCT images scanned with high spatial resolutions could not be used for proximal caries detection.

[Diagnostic accuracy of cone beam computed tomography and eight-slice computed tomography for evaluation of external root reabsorption].

OBJECTIVE: To evaluate the diagnostic accuracy of cone beam computed tomography (CBCT) and high resolution multi-slice computed tomography (MSCT) with eight-detector-rows in detecting the simulated external root resorption defects. METHODS: External root resorption defects of different sizes and in different locations were simulated in 40 human single rooted teeth. Cavities simulating root resorption defects of 1 mm in diameter and 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm in depth were drilled in the cervical, middle and apical thirds of lingual surfaces of the teeth. The specimens were scanned with both CBCT (Accuitomo 3DX, Morita Co., Japan) and high resolution 8-slice CT (BrightSpeed Edge, GE Co., USA). The CBCT and MSCT images were read by two experienced observers. The data were analyzed with receiver operating characteristics (ROC) analysis. ROC curves were generated and the area under ROC curve (Az) was employed to express the diagnostic accuracy. RESULTS: The diagnostic accuracy (Az value) in detecting the simulated defects of all the locations and sizes were 0.921 for CBCT and 0.770 for MSCT. The Az values for CBCT in detecting defects located in the cervical, middle and apical thirds were 0.885, 0.991 and 0.873, while those for MSCT were 0.752, 0.844 and 0.709, respectively. The Az values for CBCT in detecting the defects of 0.1 mm, 0.2 mm, 0.3 mm and 0.4 mm in depth were 0.794, 0.934, 0.992 and 0.992, and those for MSCT were 0.592, 0.719, 0.920 and 0.990, respectively. CONCLUSION: The diagnostic ability for external root resorption of CBCT is better than that of MSCT. Smaller defects are better delineated with CBCT than with MSCT. The defects in the middle thirds of the roots are easier to be detected than those in the cervical and apical ones using both CBCT and MSCT.

[Detection accuracy of occlusal caries by cone-beam computed tomography images scanned with different parameters].

OBJECTIVE: To compare the detection accuracy of occlusal caries in cone-beam computed tomography (CBCT) images scanned with different scanning parameters. METHODS: Thirty-seven extracted human premolars and molars without restorations or obvious cavities were selected for this study. The teeth 3 or 4 as a group were mounted in 12 plaster blocks and scanned with DCT Pro (VATECH, Co., Ltd., Yongin-Si, S.Korea) at normal and high resolution settings and with ProMax 3D (Planmeca Oy, Helsinki, Finland) at low, normal and high resolution settings. In addition, the tooth blocks were imaged with the ProMax 3D at three different tube currents. Ten doctoral candidates of Peking University School and Hospital of Stomatology evaluated all the images of the tooth blocks using a five-level confident scale. Actual presence and the extent of caries were established by histological examinations. The areas under the ROC curves (Az value) were analyzed. RESULTS: Eleven (29.7%, 11/37) teeth were sound, 13 (35.1%, 13/37) had enamel caries and 13 (35.1%, 13/37) had dentine caries. There were no significant differences between normal resolution and high resolution for DCT Pro on the detection accuracy of occlusal (enamel+dentine) caries (0.698 ± 0.064 vs. 0.735 ± 0.044, P>0.05).No significant differences were found for ProMax 3D among low, normal and high resolution (0.700 ± 0.031 vs. 0.700±0.054 vs. 0.701 ± 0.041, P>0.05). For dentinal caries, there were no significant differences between CBCT images scanned with different resolutions for DCT Pro(0.776 ± 0.078 vs. 0.811 ± 0.047, P>0.05) or ProMax 3D (0.713 ± 0.039 vs. 0.685 ± 0.063 vs. 0.713 ± 0.040, P>0.05). No significant differences were found for enamel caries detection for DCT Pro (0.620 ± 0.068 vs. 0.659 ± 0.048, P>0.05)or ProMax 3D (0.686 ± 0.050 vs. 0.685 ± 0.063 vs. 0.689 ± 0.063, P>0.05). For ProMax 3D, there were no significant differences among different tube currents on the detection accuracy of occlusal caries (0.653 ± 0.065 vs. 0.700 ± 0.054 vs. 0.67 ± 0.062, P>0.05). CONCLUSION: Different resolutions did not have an impact on the detection accuracy of occlusal caries. The tube currents for ProMax 3D did not show any effect on occlusal caries detection.

[Core needle biopsy in the diagnosis of oral and maxillofacial tumors].

OBJECTIVE: To summarize and evaluate the utility of core needle biopsy in diagnosis of head neck tumors. METHODS: Lesions were performed with core needle biopsy in 47 patients who were considered with tumors or other diseases in the head neck. According to the pathological diagnoses, their treating plans were made. If the pathological results could not give definite diagnoses and the lesions were considered tumors or other diseases, then operation or another biopsy was needed and, the other patients could be followed-up. The accurate rate was calculated. RESULTS: The biopsy tissue was enough for pathological diagnosis and immunohistochemical staining. Compared with the pathological results and follow-up, positive diagnosis was in 36 cases, negative diagnosis in 9 cases, false-negative in 2 cases, and the accurate rate was 95.7%. The pathological results had guided the treatment in 43 patients, accounting for 91.5%. No serious side effects were found. CONCLUSION: The core needle biopsy is significant for diagnosis and treatment of head neck tumors.

Role of CT Images in the Diagnosis of Common Acute Abdominal Diseases in General Surgery.

Acute abdomen is a clinical emergency disease with acute abdominal pain as the main prominent feature. Through severe disease changes in intra-abdominal, extrapelvic, and retroperitoneal tissues and organs, symptoms and clinical signs led by abdominal pain are formed. This article mainly explores the role of CT imaging diagnosis in common acute abdominal diseases in general surgery. In this paper, the use of computer-aided CT scan imaging technology in pulmonary nodules was firstly investigated, and the image segmentation algorithms based on CT images were given, including the spatial domain fuzzy C-mean clustering separation algorithm and the spatial domain fuzzy clustering level set semiautomatic separation algorithm, then the treatment of acute abdomen under the concept of ERAS was explored, and the treatment of ERAS under CT images of the acute abdomen was analyzed and studied. The empirical research results show that the ERAS's concept is guided by the undergoing national nutritional support with the traditional perioperative management. Compared to 12.9% of complications in traditional CPM groups, the recall rate of complications after ERAS group was only 6.01%, the improvement was obvious and the results were statistically significant (P < 0.05). Postoperative hospitalization time was also 4.62 days from 7.93 days, thus controlling the clinical risks of perioperative periods, providing a benefit to patient life.

Primary Hyper-IgE-Related Salivary Gland Disease: A New Disease Entity.

OBJECTIVES: To clarify the clinicopathological characteristics of primary hyper-IgE-related salivary gland disease (PHIESD), which is a newly proposed entity. METHODS: Fifteen consecutive patients pathologically diagnosed with chronic sialadenitis were enrolled, and their clinicopathological features were comprehensively analyzed. INCLUSION CRITERIA: (1) multiple salivary gland enlargement; (2) elevated serum IgE and/or IgE-positive cell infiltration in salivary gland tissues; (3) histology-confirmed lymphoplasmacytic infiltration; (4) exclusion of other known diseases. RESULTS: The male-to-female ratio was 5:10. The median age was 21 (range, 3-63) years. The average number of affected glands was 3.7 ± 1.4. Submandibular, parotid, and sublingual glands were involved in 15, 8, and 2 patients, respectively. Comorbid diseases included allergic diseases in seven patients and autoimmune diseases in two. Elevated serum IgE (median 175 kU/L) was seen in all patients. Serum IgG4 was slightly elevated in three patients. Histologically, most patients had mild lesions, including mild lymphocyte infiltration (60%) and focal fibrosis (66.7%). Lymphoid follicular formation (53.3%), moderate to severe lymphocytic inflammation (40%) and severe fibrosis (33.3%) were also observed. Immunohistochemically, IgE-positive cells infiltrated mainly around the ducts, with scattered infiltration of IgG4-positive, mast, and interleukin-4 positive cells. During follow-up (median, 46 months) of ten patients without intervention and two with immunosuppressive therapy, no significant changes in gland size or serum IgE level were noted. CONCLUSIONS: PHIESD manifests as homogeneous enlargement of multiple salivary glands and elevated serum IgE. Histopathology further verifies the diagnosis. It might be associated with anaphylaxis or autoimmune dysfunction. Conservative treatment is suggested. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:2132-2138, 2022.

Circular RNA expression profiling identifies specific circular RNAs in tongue squamous cell carcinoma.

Tongue squamous cell carcinoma (TSCC) is the most frequent type of oral cancer associated with high malignancy. Circular RNAs (circRNAs) are a form of non­coding RNA with stable and conserved expression in mammalian cells. The aim of the present study was to investigate circRNAs expression profiles in TSCC, and examine the roles and potential mechanisms of circRNA­081069 (circ_081069). A high­throughput circRNA microarray analysis of tumor samples and adjacent normal tissues from four patients with TSCC was performed. Bioinformatic analysis was conducted to screen the differentially expressed circRNAs. Reverse transcription­quantitative PCR was performed to confirm the microarray results. A migration assay and proliferation assay were performed to detect the migratory and proliferative ability of TSCC cells. A luciferase assay was conducted to investigate the interaction between circ_081069 and microRNA (miRNA/miR)­665. In total, 335 circRNAs were found to be differentially expressed in tumor tissues. Among them, 59 were upregulated and 276 were downregulated (P<0.05; fold change ≥2 or ≤0.5). A total of seven circRNAs, including two upregulated and five downregulated circRNAs, were further confirmed using quantitative PCR analysis in the ten paired TSCC tissues and adjacent normal tissues. The present study showed that circRNA_081069 promoted the migratory and proliferative ability of TSCC cells in vitro. Furthermore, the potential circRNA­miRNA interactions were predicted, and the present results identified miR­665 as a miRNA target of circ_081069. The present results suggested that circRNAs may be involved in TSCC development, and understanding the interaction between circ_081069 and miR­665 may facilitate the development of novel diagnostic and therapeutic targets for TSCC.

Relationship between CNR and visibility of anatomical structures of cone-beam computed tomography images under different exposure parameters.

OBJECTIVES: The purpose of this study was to investigate the image quality of cone beam CT (CBCT) under different exposure parameters and the relationship between contrast-to-noise and visibility of eight anatomical structures. METHODS: CBCT images for the evaluation of subjective image quality were acquired on an anthropopathic phantom containing a human skeleton embedded in soft tissue equivalent materials using 25 exposure protocols. Visibility of eight anatomical structures was evaluated by five independent observers. Using the SEDENTEXCT IQ Image Quality phantom, the contrast-to-noise ratio (CNR) was calculated by ImageJ software. RESULTS: A reduction on the visibility of anatomical structures was seen under lower exposure parameters. However, for 84% of the protocols, visibility of anatomical structures remained acceptable even under some lower parameter settings. As CNR increased, the visibility of anatomical structures also increased correspondingly. A change point could be found in the CNR interval 29.42-36.51 after which the visibility of anatomical structures no longer increases with the increase of CNR. CONCLUSIONS: Although CNR decrease under a lower exposure parameter, the image quality often remained acceptable at exposure levels below the manufacture's recommended settings. It is possible to standardize subjective image quality by physical factors. Currently, it is not possible to predetermine a change point CNR value due to different CBCT machine and variation of diagnostic tasks.

Evaluation of trabecular structure changes in osteoarthritis of the temporomandibular joint with cone beam computed tomography imaging.

OBJECTIVES: To explore the possibility of using 2-dimensional image assessments in combination with cone beam computed tomography (CBCT) in patients with temporomandibular joint osteoarthritis (TMJOA) to enhance the clinical significance and applicability of the CBCT findings on TMJOA changes. STUDY DESIGN: Fifty-two patients with unilateral TMJOA and 40 healthy adults who had undergone CBCT in preparation for orthodontic treatment were selected for this study. Temporomandibular joint images were acquired with CBCT. All images were classified into 4 phases (slight erosion, widespread erosion, appearance of bone maintenance, and partial loss of condylar head with a remodeled cortical surface) and 4 levels of severity (absent, slight, moderate, and extensive). Quantitative microstructural analysis, including bone value fraction (BV/TV), trabecular number (Tb.N), trabecular thickness, and trabecular separation (Tb.Sp) of each image, was performed by using a customized software. RESULTS: In patients with unilateral TMJOA, the affected side had significantly higher BV/TV and Tb.N and significantly lower Tb.Sp compared with the unaffected side. Compared with healthy individuals, the affected joints in patients with TMJOA had significantly higher BV/TV and trabecular thickness and significantly lower Tb.N and Tb.Sp. No significant difference was found among different phase groups or different severity levels. CONCLUSIONS: CBCT combined with a software investigation protocol for microstructure measurement can be used to provide reliable trabecular parameters in assessing TMJOA.

Comparison of micro-CT and cone beam CT on the feasibility of assessing trabecular structures in mandibular condyle.

OBJECTIVES: To evaluate the accuracy of CBCT in assessing trabecular structures. METHODS: Two human mandibles were scanned by micro-CT (Skyscan 1173 high-energy spiral scan micro-CT; Skyscan NV, Kontich, Belgium) and CBCT (3D Accuitomo 170; Morita, Japan). The CBCT images were reconstructed with 0.5 and 1 mm thicknesses. The condylar images were selected for registration. A parallel algorithm for histogram computation was introduced to perform the registration. A mutual information (MI) value was used to evaluate the match between the images obtained from micro-CT and CBCT. RESULTS: In comparison with the micro-CT image for the two samples, the CBCT image with 0.5 mm thickness has a MI value of 0.873 and 0.903 while that with 1.0 mm thickness has a MI value of 0.741 and 0.752. The CBCT images with 0.5 mm thickness were better matched with micro-CT images. CONCLUSIONS: CBCT shows comparable accuracy with high-resolution micro-CT in assessing trabecular structures. CBCT can be a feasible tool to evaluate osseous changes of jaw bones.

Ultrasonographic Features of Immunoglobulin G4-Related Sialadenitis.

The aim of this study was to determine the role of ultrasonography in the diagnosis and follow-up evaluation of immunoglobulin G4-related sialadenitis. In this study, 42 patients with immunoglobulin G4-related sialadenitis underwent ultrasonography of the parotid and submandibular glands, and the sonographic appearance was compared with the pathologic findings. Post-treatment ultrasonographic appearance was compared with the pre-treatment findings in 30 patients who received immunomodulatory therapy. The ultrasonographic appearance of the affected glands was divided into five patterns: superficial hypo-echoic, multiple hypo-echoic foci, whole-gland heterogeneity, space occupying and normal echo. Histopathologic examination revealed marked lymphoplasmacytic inflammation and inter-lobular fibrosis, which were more severe in the superficial than deep portion of the affected glands. After treatment, the volume of the affected gland decreased significantly, the internal echo became more homogeneous and the superficial hypo-echoic area disappeared or was reduced. In conclusion, ultrasonography may play an important role in the diagnosis and follow-up evaluation of immunoglobulin G4-related sialadenitis.

Cheek fistula from the ectopic salivary gland: a variant of the oculo-auriculo-vertebral spectrum.

OBJECTIVES/HYPOTHESIS: This study aimed to investigate the diagnosis and management of a distinct developmental deformity syndrome characterized by congenital cheek fistula, ectopic accessory parotid gland, and preauricular appendage. STUDY DESIGN: Retrospective study. METHODS: We analyzed the medical records, radiologic and histopathologic findings, and follow-up data for seven patients (four males) with a congenital cheek salivary fistula. Computed tomography, fistulography, and sialography had been performed for diagnosis. Surgical treatment effect was evaluated. RESULTS: The mean age of the patients was 8.1 years (range, 2-16 years). The distinctive clinical feature was a congenital skin orifice lateral to the commissure with saliva discharge during eating. The cheek fistulae were accompanied by ipsilateral preauricular appendages in all seven patients. The skin orifice connected to an ectopic gland anterior to the masseter and inferior to Stensen's duct. Parotid sialography demonstrated an intact Stensen's duct in all cases. Hypoplasia of the ipsilateral mandible could be observed in five cases. Excision of the ectopic gland, skin orifice, and fistula was performed in five cases resulting in optimal treatment outcomes with no recurrent or adverse events. CONCLUSIONS: A congenital saliva-discharging fistula with an ectopic accessory parotid gland, ipsilateral preauricular appendage, and mandibular hypoplasia constitutes a rare developmental syndrome. Surgical excision can effectively treat congenital cheek salivary fistula. LEVEL OF EVIDENCE: 4.

Effects of estradiol on proliferation and metabolism of rabbit mandibular condylar cartilage cells in vitro.

OBJECTIVE: To investigate the effects in vitro of 17 beta-estradiol (E2) on the proliferation and metabolism of rabbit mandibular condylar cartilage cells. METHODS: Chondrocytes were derived from neonatal rabbit mandibular condylar cartilage using a modified enzyme method. 17 beta-estradiol was added to the culture medium in a variety of concentrations. Cell growth and DNA, collagen, and proteoglycan synthesis were used as indicators of proliferation and differentiation of condylar chondrocytes. These were measured by cell number, 3H-proline and 35S-incorporation, respectively. RESULTS: E2 increased cell number and 3H-thymidine incorporation at 10(-8) to 10(-10) mol/L, and 10(-8) to 10(-11) mol/L in a dose-dependent manner, peaking at 10(-8) mol/L and 10(-9) mol/L, respectively. However, further increase in the concentration of estradiol caused inhibition of both cell number and 3H-thymidine incorporation, and this was significant at 10(-6) mol/L. The effect of E2 on proteoglycan synthesis was similar; the maximum stimulating effect was at 10(-8) mol/L, and inhibition was significant at 10(-6) mol/L. There was no obvious stimulatory effect of E2 on 3H-thymidine incorporation observed. CONCLUSIONS: Estradiol affects condylar chondrocyte cell growth, DNA, and proteoglycan synthesis in a biphasic manner depending on its concentration. This indicates that estrogen may be important in the proliferation and differentiation of mandibular condylar chondrocytes, and could be relevant to some aspects of certain temporomandibular joint diseases by modulating the function of the chondrocytes.

[Endoscopy-assisted sialolithectomy for the calculus of the Stensen's duct].

OBJECTIVE: To investigate the clinical effects of endoscopy-assisted sialolithectomy for the calculus in the Stensen's duct. METHODS: From August 2005 to July 2013, 67 consecutive patients with calculus (or foreign bodies) in the Stensen's duct underwent explorative and interventional endoscopy in our hospital. The stones (or foreign bodies) were removed by endoscopy-assisted technique. After operation, the patients were followed-up periodically, and treatment effects were analyzed. RESULTS: Among the 67 patients, the stones (or foreign bodies) were completely removed in 58 cases, and almost completely removed in 3 cases, with a success rate of 87% (58/67). Among the 61 stone-removed cases, treatment options included direct removal with aid of basket or forceps (24 cases), basket entrapment and opening-up of the ostium (21 cases), basket entrapment and mucosal incision near the ostium (8 cases), open removal via buccal incision (2 cases) and open removal via pre-auricular flap (6 cases). During the 6-90 months' follow-up of the 61 cases, 48 cases were asymptomatic, 7 had mild symptoms, 3 developed ductal obturation, 1 had numbness in the parotid region, and the remaining 2 were missed. CONCLUSIONS: Endoscopy-assisted sialolithectomy is a safe and effective gland-preservation technique for the patients with parotid gland calculus.

Thyroid shields for radiation dose reduction during cone beam computed tomography scanning for different oral and maxillofacial regions.

AIMS: To evaluate the radiation dose level during cone beam computed tomography (CBCT) scanning for the different oral and maxillofacial regions with and without thyroid collar shielding. MATERIALS AND METHODS: Average tissue-absorbed dose for a DCT PRO CBCT was measured using thermoluminescent dosimeter chips in a phantom with or without applying thyroid collars. Effective organ dose and total effective dose were derived using International Commission on Radiological Protection (ICRP) 2007 recommendations. RESULTS: The total effective doses for large, middle and small field of view (FOV) were 254.3 µSv, 249.0 µSv and 180.3 µSv, respectively, when no thyroid collar was used. Applying one thyroid collar around the front neck can reduce the total effective doses to 208.5 µSv (18.0% reduction), 149.1 µSv (40.1% reduction) and 110.5 µSv (38.7% reduction), respectively. When two thyroid collars were used around the front and back neck, the total effective doses were reduced to 219.1 µSv (13.8% reduction), 142.0 µSv (43.0% reduction) and 105.5 µSv (41.5% reduction), respectively. CONCLUSIONS: Thyroid collar can reduce the radiation dose during CBCT scanning for the oral and maxillofacial regions. The dose reduction becomes more significant when middle or small FOV is chosen.