Root proximity of the anchoring miniscrews of orthodontic miniplates in the mandibular incisal area: Cone-beam computed tomographic analysis / 대한치과교정학회지

Objective@#This outcome analysis study evaluated the actual positions of the orthodontic miniplate and miniplate anchoring screws (MPASs) and the risk factors affecting adjacent anatomic structures after miniplate placement in the mandibular incisal area. @*Methods@#Cone-beam computed tomographic images of 97 orthodontic miniplates and their 194 MPASs (diameter, 1.5 mm; length, 4 mm) in patients whose miniplates provided sufficient clinical stability for orthodontic treatment were retrospectively reviewed. For evaluating the actual positions of the miniplates and analyzing the risk factors, including the effects on adjacent roots, MPAS placement height (PH), placement depth (PD), plate angle (PA), mental fossa angle (MA), and root proximity were assessed using the paired t-test, analysis of variance, and generalized linear model and regression analyses. @*Results@#The mean PDs of MPASs at positions 1 (P1) and 2 (P2) were 2.01 mm and 2.23 mm, respectively. PA was significantly higher in the Class III malocclusion group than in the other groups. PH was positively correlated with MA and PD at P1. Of the 97 MPASs at P1, 49 were in the no-root area and 48 in the dentulous area; moreover, 19 showed a degree of root contact (19.6%) without root perforation. All MPASs at P2 were in the no-root area. @*Conclusions@#Positioning the miniplate head approximately 1 mm lower than the mucogingival junction is highly likely to provide sufficient PH for the P1-MPASs to be placed in the no-root area.

Root proximity of the anchoring miniscrews of orthodontic miniplates in the mandibular incisal area: Cone-beam computed tomographic analysis / 대한치과교정학회지

Objective@#This outcome analysis study evaluated the actual positions of the orthodontic miniplate and miniplate anchoring screws (MPASs) and the risk factors affecting adjacent anatomic structures after miniplate placement in the mandibular incisal area. @*Methods@#Cone-beam computed tomographic images of 97 orthodontic miniplates and their 194 MPASs (diameter, 1.5 mm; length, 4 mm) in patients whose miniplates provided sufficient clinical stability for orthodontic treatment were retrospectively reviewed. For evaluating the actual positions of the miniplates and analyzing the risk factors, including the effects on adjacent roots, MPAS placement height (PH), placement depth (PD), plate angle (PA), mental fossa angle (MA), and root proximity were assessed using the paired t-test, analysis of variance, and generalized linear model and regression analyses. @*Results@#The mean PDs of MPASs at positions 1 (P1) and 2 (P2) were 2.01 mm and 2.23 mm, respectively. PA was significantly higher in the Class III malocclusion group than in the other groups. PH was positively correlated with MA and PD at P1. Of the 97 MPASs at P1, 49 were in the no-root area and 48 in the dentulous area; moreover, 19 showed a degree of root contact (19.6%) without root perforation. All MPASs at P2 were in the no-root area. @*Conclusions@#Positioning the miniplate head approximately 1 mm lower than the mucogingival junction is highly likely to provide sufficient PH for the P1-MPASs to be placed in the no-root area.

Cone-beam computed tomography of mandibular foramen and lingula for mandibular anesthesia

Purpose@#The positions of the mandibular foramen (MnF) and the lingula affect the success rate of inferior alveolar nerve block. The objective of this study was to investigate aspects of the MnF and the lingula relevant for mandibular block anesthesia using cone-beam computed tomography (CBCT). @*Materials and Methods@#Fifty CBCT scans were collected from a picture archiving and communications system. All scans were taken using an Alphard Vega 3030 (Asahi Roentgen Co. Ltd., Kyoto, Japan). Fifty-eight MnFs of 30 subjects were included in the study. The position of the MnF, the size of the MnF, the position of the lingula, the size of the lingula, and the shape of the lingula were measured and recorded. All data were statistically analyzed at a significance level of p<0.05. @*Results@#The position of MnF was 0.1 mm and 0.8 mm below the occlusal plane in males and females, respectively. The horizontal position of the MnF was slightly anterior to the center of the ramus in males and in the center in females (p<0.05). The vertical position of the MnF was lower in females than in males (p<0.05). The MnF was an oval shape with a longer anteroposterior dimension. The height of the lingula was 9.3 mm in males and 8.2 mm in females. The nodular type was the most common shape of the lingula, followed by the triangular, truncated, and assimilated types. @*Conclusion@#CBCT provided useful information about the MnF and lingula. This information could improve the success rate of mandibular blocks.

Leiomyosarcoma of the jaw: case series

Objectives@#Leiomyosarcoma is a malignant neoplasm that affects smooth muscle tissue and it is very rare in the field of oral and maxillofcial surgery.The purpose of this study was to obtain information on diagnosis of and treatment methods for leiomyosarcoma by retrospectively reviewing of the cases. @*Patients and Methods@#The study included nine patients who were diagnosed with leiomyosarcoma in the Department of Oral and Maxillofacial Surgery at Seoul National University Dental Hospital. The subjects were analyzed with respect to sex, age, clinical features, primary site of disease, treatment method, recurrence, and metastasis. @*Results@#Particular clinical features included pain, edema, mouth-opening limitations, dysesthesia, and enlarged lymph nodes. All cases except one were surgically treated, and recurrence was found in two cases. Four of nine patients were followed up without recurrence and one patient underwent additional surgery due to recurrence. @*Conclusion@#In our case series, notable symptoms included pain, edema, mouth-opening limitations, and dysesthesia; however, it was difficult to label these as specific symptoms of leiomyosarcoma. Considering the aggressive characteristics of the disease and poor prognosis, surgical treatment is necessary with careful consideration of postoperative radiotherapy and chemotherapy.

Power Doppler ultrasound-guided sialography using the phenomenon of increased blood flow: A technical report

PURPOSE: This report presents a procedure for performing power Doppler ultrasound-guided sialography using the phenomenon of increased blood flow and illustrates its application to practical patient cases.MATERIALS AND METHODS: The salivary gland was scanned using ultrasound equipment (GE LOGIQ5 Expert® device; GE Medical Systems, Milwaukee, WI, USA) to identify pathological findings related to the patient's chief complaint. To identify the orifice of the main duct, it should be cannulated using a lacrimal dilator. After inserting the catheter into the cannulated main duct, the position of the catheter within the duct was confirmed by ultrasound. A contrast agent was injected until the patient felt fullness, and ultrasound (B-mode) was used to confirm whether the contrast agent filled the main canal and secondary and tertiary ducts. Then, power Doppler ultrasound was performed to determine whether the salivary gland had increased blood flow.RESULTS: In 2 cases in this report, a power Doppler ultrasound scan showed a significant increase in blood flow after contrast medium injection, which was not observed on a preoperative scan.CONCLUSION: Power Doppler ultrasound was found to be a simple, safe, and effective tool for real-time sialography monitoring.

Multiple implant therapy with multiple inductions of general anesthesia in non-compliant patients with schizophrenia: A case report

The effectiveness of dental implants in patients with disability, who are non-compliant during treatment, is controversial because of their poor oral health. Thus, oral health-care and management in such patients is concerning. Moreover, limited information is available on prognosis after implant placement. Herein, we describe a patient with schizophrenia who underwent dental implantation under multiple inductions of general anesthesia (5 times) and required conservative treatment and tooth extraction for multiple dental caries and retained roots because of inadequate oral health-care. Postoperatively, fracture of the prosthodontics and progression of dental caries were observed, and with 3 additional inductions of general anesthesia, conservative treatment, implant surgery, and prosthesis implantation were conducted. Postoperative 12-month follow-up since the last prosthesis implantation showed successful results. For patients with schizophrenia, multiple implantation can reduce horizontal bone loss and achieve aesthetic results compared to treatment with removable prosthodontics and could serve as an alternative treatment modality.

Diagnostic considerations in central odontogenic fibroma of the maxilla: 2 case reports

Central odontogenic fibroma (COF) is defined as a fibroblastic odontogenic tumor characterized by varying density of the tooth epithelium. It is an extremely rare benign neoplasm that occurs in the maxilla and the mandible; only a few reports of COF are available in the literature. Diagnosis of the lesion based only on the radiological features of COF is difficult due to variation in the findings regarding this condition. This report describes 2 clinical cases of middle-aged women with COF. Clinical examination revealed palatal mucosal depression; additionally, oral examination, as well as panoramic radiographs, intraoral radiographs, and computed tomography scans, revealed severe root resorption. This report highlights the clinical and radiological imaging features of COF, with the goal of enabling straightforward differential diagnosis of the lesion by the clinician and thereby appropriate treatment of the patient.

Unusual malignant neoplasms occurring around dental implants: A report of 2 cases

Osseointegrated implants are now commonplace in contemporary dentistry. However, a number of complications can occur around dental implants, including peri-implantitis, maxillary sinusitis, osteomyelitis, and neoplasms. There have been several reports of a malignant neoplasm occurring adjacent to a dental implant. In this report, we describe 2 such cases. One case was that of a 75-year-old man with no previous history of malignant disease who developed a solitary plasmacytoma around a dental implant in the left posterior mandible, and the other was that of a 43-year-old man who was diagnosed with squamous cell carcinoma adjacent to a dental implant in the right posterior mandible. Our experiences with these 2 cases suggest the possibility of a relationship between implant treatment and an inflammatory cofactor that might increase the risk of development of a malignant neoplasm.

Linear accuracy of cone-beam computed tomography and a 3-dimensional facial scanning system: An anthropomorphic phantom study

PURPOSE: This study was conducted to evaluate the accuracy of linear measurements of 3-dimensional (3D) images generated by cone-beam computed tomography (CBCT) and facial scanning systems, and to assess the effect of scanning parameters, such as CBCT exposure settings, on image quality. MATERIALS AND METHODS: CBCT and facial scanning images of an anthropomorphic phantom showing 13 soft-tissue anatomical landmarks were used in the study. The distances between the anatomical landmarks on the phantom were measured to obtain a reference for evaluating the accuracy of the 3D facial soft-tissue images. The distances between the 3D image landmarks were measured using a 3D distance measurement tool. The effect of scanning parameters on CBCT image quality was evaluated by visually comparing images acquired under different exposure conditions, but at a constant threshold. RESULTS: Comparison of the repeated direct phantom and image-based measurements revealed good reproducibility. There were no significant differences between the direct phantom and image-based measurements of the CBCT surface volume-rendered images. Five of the 15 measurements of the 3D facial scans were found to be significantly different from their corresponding direct phantom measurements (P < .05). The quality of the CBCT surface volume-rendered images acquired at a constant threshold varied across different exposure conditions. CONCLUSION: These results proved that existing 3D imaging techniques were satisfactorily accurate for clinical applications, and that optimizing the variables that affected image quality, such as the exposure parameters, was critical for image acquisition.

Reverse Total Shoulder Replacement for an Enchondroma with Concomitant Rotator Cuff Tear Arthropathy: A Case Report

Enchondromas generally occur in the hand and uncommonly in the long bones. Because enchondromas are usually asymptomatic, most are discovered during diagnostic radiology for another disease. Here, we describe a case of enchondroma in the right humerus in a 79-year-old female patient with concomitant rotator cuff tear arthropathy. The patient was initially hospitalized for prolonged pain and pseudoparalysis of the right shoulder. The condition, which was histologically confirmed as an enchondroma in the proximal humerus, was treated with curettage and reverse total shoulder arthroplasty. In this case report, we present a rare case of an enchondroma with combined rotator cuff tear arthropathy.