Image findings of bisphosphonate related osteonecrosis of jaws comparing with osteoradionecrosis.

OBJECTIVES: The aim of this study was to evaluate image characteristics of bisphosphonate-related osteonecrosis of the jaws (BRONJ) and compare these with osteoradionecrosis (ORN). METHODS: 34 patients with BRONJ and 16 patients with ORN were included in this study. We investigated the CT and dental panoramic radiograph (DPR) images for osteolysis, osteosclerosis, sequestration, periosteal reaction, pathological fracture and spread of soft tissue inflammation around the jaws. RESULTS: Osteolysis, osteosclerosis, sequestration and spread of soft tissue inflammation around the jaws were common radiological features in both BRONJ and ORN. Osteolysis and spreading of soft tissue inflammation around the jaws were predominant in ORN, and by contrast osteosclerosis was predominant in BRONJ. Periosteal reaction was established in 15 of the 34 BRONJ cases, but none in the ORN cases. Pathological fractures were observed in 6 of 16 ORN cases, but none in BRONJ cases. CT was better for detection than DPR for osteolysis, osteosclerosis, sequestration and periosteal reactions. CONCLUSIONS: Image findings of BRONJ were characterized as a severe sclerotic change combined with osteolysis, sequestration, periosteal reaction and spread of soft tissue inflammation around the jaws.

Changes in parotid gland morphology and function in patients treated with intensity-modulated radiotherapy for nasopharyngeal and oropharyngeal tumors.

OBJECTIVE: To evaluate the morphological changes of the parotid glands in patients treated with intensity-modulated radiotherapy (IMRT) for nasopharyngeal and oropharyngeal tumors and the correlations with parotid function. METHODS: Ten patients with nasopharyngeal and oropharyngeal tumors treated with IMRT between May 2009 and January 2010 at Hokkaido University Hospital were included in this study. In the morphological assessment of the parotid glands, the sizes and computed tomography (CT) numbers of the bilateral parotid glands before and after IMRT with CT were calculated. For functional assessment of the parotid glands, we conducted the Saxon test and used a visual analog scale (VAS) for xerostomia evaluation. RESULTS: Reductions in saliva secretion were observed in the patients treated with IMRT for nasopharyngeal and oropharyngeal tumors, and there was a significant correlation between the reduction in saliva secretion and the VAS. The reductions in the parotid gland size and CT number were larger on the ipsilateral side than on the contralateral side. The reduction in saliva secretion was not significantly correlated with the reduction in parotid gland size, but was significantly correlated with the reduction in CT number. CONCLUSIONS: Morphological and functional changes of the parotid glands were observed after IMRT for nasopharyngeal and oropharyngeal tumors, and preservation of the contralateral parotid glands was only partly achieved. Among the morphological changes of the parotid glands, the CT number may be considered a predictor of parotid function after radiotherapy.

An investigation of accidental ingestion during dental procedures.

Twenty-three cases of accidental ingestion during dental procedures, which occurred at the Center for Dental Clinics of Hokkaido University Hospital between 2006 and 2010, were analyzed retrospectively. We examined not only the objects ingested, but also details of the circumstances (treated teeth, types of treatment, professional experience of the practitioners). Except for two cases (an unidentified endodontic file and the tip of an ultrasonic scaler, which were recovered by vacuuming), the other 21 accidentally ingested objects were all found in the digestive tract, and none in the respiratory tract, by radiographic examination of the chest and abdomen. The ingested objects were mostly metal restorations (inlays or onlays) or prostheses (crowns or cores). Ingestion occurred more frequently during treatment of lower molars, and when procedures were being conducted by practitioners with less than 5 years of experience. No adverse events related to ingestion were reported. The present study found no cases of aspiration or complications related to the ingested objects. However, considering the risk of life-threatening emergencies related to accidental aspiration and ingestion, dentists must take meticulous precautions and be ready to deal with this kind of emergency during dental procedures.

Cesium implant for tongue carcinoma with a thickness of 1.5 cm or more: cases successfully treated with a Modified Manchester System.

PURPOSE: Deciding on treatment carcinoma of the tongue when the tumor has a thickness of 1.5 cm or more is difficult. Surgery often requires wide resection and re-construction, leading to considerable functional impairment. A cesium implant is an attractive option, but according to the Manchester System, a two plane implant is needed. MATERIALS AND METHODS: According to the textbook, a tumor is sandwiched between the needles, which are implanted at the edge of the tumor. This may cause an unnecessarily high dose to the outer surface of the tongue, which sometimes leads to a persistent ulcer. To avoid this complication, we invented a modified implantation method, and applied the method to five consecutive patients. RESULTS: With a minimum follow-up of 2 years, all primary tumors in 5 consecutive patients have been controlled. No complications occurred in soft tissue of the tongue or in the mandible. CONCLUSION: Our modified Manchester System was feasible and effective for tumors that has a thickness of 1.5 cm or more.

A comparison of diagnostic tools for Sjögren syndrome, with emphasis on sialography, histopathology, and ultrasonography.

OBJECTIVE: The present study examined the reliability and correlation of sialography, salivary gland biopsy, and ultrasonography for Sjögren syndrome (SS) and evaluated the usefulness of ultrasonography as a diagnostic tool for SS compared with sialography and histopathology. STUDY DESIGN: Seventy-three patients who underwent sialography, ultrasonography, and salivary gland biopsy were included in this study. The study evaluated the diagnostic reliability and correlation of each kind of examination with SS. RESULTS: There was a statistically significant difference in the sensitivities of sialography and histopathology, in the specificities of sialography and ultrasonography, and in the accuracies of sialography and both ultrasonography and histopathology. The correlation coefficient (r) between sialography and ultrasonography was significantly higher than the others and indicated a good correlation. CONCLUSIONS: Ultrasonography can be used as a diagnostic tool for SS, with its advantage of noninvasiveness and ease of use.

Experience of high-dose-rate brachytherapy for head and neck cancer treated by a customized intraoral mold technique.

Radiotherapy of head and neck cancer has become more successful with the advances in treatment modalities and use of a multidisciplinary approach. Higher quality treatment and a team approach to radiotherapy have thus been required for head and neck cancer. This study presents the clinical experience of high-dose-rate (HDR) brachytherapy for head and neck cancer treated by a customized intraoral mold technique. Two patients are reported for whom we created dental prostheses as the radiation carriers for HDR brachytherapy of their head and neck cancers. HDR brachytherapy with the dental prostheses reported here was feasible and effective for eradicating the head and neck cancer. It has been demonstrated that HDR brachytherapy using a customized intraoral technique can be a treatment option for patients who are not candidates for surgery or external irradiation. It is strongly suggested that specialized dentists are needed who are familiar with not only the anatomy and function of the head and neck region but also radiotherapy. Dental radiologists should take responsibility for constructing irradiation prostheses. If they do, they have the potential to improve the quality of life of patients who undergo radiotherapy for head and neck cancer.

Uncertainty in treatment of head-and-neck tumors by use of intraoral mouthpiece and embedded fiducials.

PURPOSE: To reduce setup error and intrafractional movement in head-and-neck treatment, a real-time tumor tracking radiotherapy (RTRT) system was used with the aid of gold markers implanted in a mouthpiece. METHODS AND MATERIALS: Three 2-mm gold markers were implanted into a mouthpiece that had been custom made for each patient before the treatment planning process. Setup errors in the conventional immobilization system using the shell (manual setup) and in the RTRT system (RTRT setup) were compared. Eight patients with pharyngeal tumors were enrolled. RESULTS: The systematic setup errors were 1.8, 1.6, and 1.1 mm in the manual setup and 0.2, 0.3, and 0.3 mm in the RTRT setup in right-left, craniocaudal, and AP directions, respectively. Statistically significant differences were observed with respect to the variances in setup error (p <0.001). The systematic and random intrafractional errors were maintained within the ranges of 0.2-0.6 mm and 1.0-2.0 mm, respectively. The rotational systematic and random intrafractional errors were estimated to be 2.2-3.2 degrees and 1.5-1.6 degrees , respectively. CONCLUSIONS: The setup error and planning target volume margin can be significantly reduced using an RTRT system with a mouthpiece and three gold markers.

Effect of treatment time on outcome of radiotherapy for oral tongue carcinoma.

PURPOSE: To investigate the importance of total treatment time on the outcome of external beam radiotherapy (EBRT) followed by internal brachytherapy for the treatment of oral tongue carcinoma. METHODS AND MATERIALS: Ninety-four patients with T1-T2N0 squamous cell carcinoma of the oral tongue were treated using 35-40 Gy EBRT followed by 35-40 Gy interstitial (137)Cs brachytherapy between 1985 and 1995. The interval between the end of EBRT and the start of interstitial treatment varied for numerous unavoidable reasons, with a mean of 25.3 days and standard deviation of 3.5 days. The median follow-up period was 59.1 months (range 6-146). RESULTS: The actuarial survival rate of all cases was 78.4% at 5 years. The 5-year local control rate for those with T1 and T2 was 92.8% and 62.7%, respectively (p < 0.05). The local control rate of the primary tumor in patients with a total treatment time >43 days was statistically lower than that of patients with a total treatment time < or =43 days in all patients (p < 0.05) and in the subgroup of Stage T2 patients (p < 0.05). Multivariate analysis revealed that the local control rates in all cases were significantly related to the T stage (T2 or not), total treatment time (>43 days or not), and location of disease (posterior or not). Regression analysis for 5-year local control as a function of treatment duration showed a 2% loss of local control per day of treatment extension >30 days (r = 0.94, p < 0.01). CONCLUSION: The total treatment time was associated with the local control rate in the RT of oral tongue carcinoma. The loss in local control was estimated to be 2.0% per additional day in our series for oral tongue carcinoma.

Clinical study of a spacer to help prevent osteoradionecrosis resulting from brachytherapy for tongue cancer.

OBJECTIVE: We sought to describe a simple method to construct a spacer and to evaluate with the use of computed tomography the spacer's effectiveness in preventing osteoradionecrosis of the mandible. STUDY DESIGN: Fifty-three patients with oral tongue cancers who were treated by means of interstitial brachytherapy were included in this study. Patients underwent a computed tomography examination immediately after the implantation of radioactive sources, with the spacers in place. Distances between the radioactive sources and the lingual surfaces of the mandible were measured on transverse computed tomographs and were evaluated in terms of the development of osteoradionecrosis in the mandible. RESULTS: Statistically significant differences in the frequency of osteoradionecrosis were observed between patients who had received spacers equal to or thicker than 5 mm and those who had received spacers less than 5 mm thick. CONCLUSION: A spacer should have a minimum thickness of 5 mm on its lingual flange to prevent the development of osteoradionecrosis of the mandible.