Faculty Bibliography

BACKGROUND AND OBJECTIVE: The most common risk factor for bisphosphonate-related osteonecrosis of the jaws (BRONJ) is dentoalveolar surgery. It has been suggested that reduced serum C-terminal telopeptide (CTX) can determine the degree of osteoclast suppression and may predict the development of BRONJ after dentoalveolar surgery. Although there are many radiographic appearances associated with BRONJ, there are little data that describes changes preceding dentoalveolar surgery. The objective of this retrospective study was: 1) to investigate if reduced serum CTX values (i.e., <150 pg/mL) were associated with BRONJ after dentoalveolar surgery; and 2) to determine if specific radiographic changes are associated with teeth that develop BRONJ after extraction. STUDY DESIGN: A retrospective review of radiographic and/or serum CTX data was performed for 68 patients with a history of bisphosphonate therapy who either underwent dental extraction or were diagnosed with BRONJ in the Department of Oral and Maxillofacial Surgery during the period 2007-2009. Postoperative healing was assessed for 26 patients with reduced serum CTX levels (<150 pg/mL) who either underwent dental extraction or treatment for BRONJ. Preoperative radiographs were evaluated for 55 patients who either healed normally or developed BRONJ after dental extraction. RESULTS: All 26 patients (100%) who had serum CTX levels <150 pg/mL healed successfully after dentoalveolar surgery (20 patients) or after treatment for BRONJ (6 patients). Among the 55 patients who underwent radiographic evaluation, 24 patients (83%) with BRONJ exhibited periodontal ligament (PDL) widening associated with extracted teeth, whereas only 3 patients (11%) who healed normally demonstrated PDL widening. CONCLUSION: These data suggest that radiographic PDL widening may be a more sensitive indicator than CTX testing in predicting risk of BRONJ. Current guidelines that recommend minimal surgical intervention may need to be revised to include alternative strategies for the elimination or management of this pathology.

Obstructive sleep apnea (OSA) is a condition of partial or complete upper airway obstruction leading to increased resistance to airflow and potential cessation of breathing during sleep. Effective treatment of OSA is challenging and there has been greater recognition by the medical and dental disciplines. By understanding the rationale, indications, benefits, risks and success of the various treatment options available, clinicians will be able to make more informed treatment recommendations in patient management

BACKGROUND AND PURPOSE: Our aim was to assess dynamic half-Fourier acquired single-shot turbo spin-echo (HASTE) MR imaging of the temporomandibular joint (TMJ) using parallel imaging, in comparison with static proton density (Pd) imaging. MATERIALS AND METHODS: Thirty-four TMJs from 17 subjects (7 volunteers, 10 patients) were imaged in a multichannel head coil on a 1.5 T magnet by using a 35-second dynamic sagittal HASTE acquisition (TR/TE, 1180/65 msec; matrix, 128 x 128; section thickness, 7 mm; 30 images) and sagittal oblique Pd in closed- and open-mouthed positions (TR/TE, 1800/12 msec; matrix, 256 x 256; section thickness, 2 mm; 15 sections). Images were reviewed by 3 readers and rated for confidence of disk position, presence of motion artifact, range of motion, and presence of disk displacement on a 5-point scale. Consensus review of cases was also performed to assess disk dislocation and limited range of motion. RESULTS: More static examinations were rated as having motion artifact (19.6% versus 6.9%, P=.016), limited range of motion (30.4% versus 17.7%, P=.016), and disk dislocations (31.4% versus 22.6%, P=.071). Confidence ratings were higher on dynamic examinations (4.11 versus 3.74, P=.018). Chi-squared tests demonstrated no significant difference in consensus reviews of the 2 examination types. CONCLUSION: Dynamic HASTE TMJ MR imaging is a time-efficient adjunct to standard MR imaging protocols, producing fewer motion artifacts, additional range of motion information, and a dynamic assessment of disk position, when compared with static imaging. Further study is needed to evaluate the role of this sequence in diagnosing disk displacement

Gene expression profiling of oral premalignant (OPM) cells and normal oral epithelial (NOR) cells showed that EMMPRIN expression was markedly upregulated in OPM cells compared to NOR cells. We used an oral squamous cell carcinoma (OSCC) progression model composed of cell lines, organotypic cultures and tissue specimens to characterize EMMPRIN expression patterns by microarray analysis, qRT-PCR, Western blotting and immunohistochemistry. EMMPRIN levels are elevated in OPM and primary and metastatic OSCC cells as compared to NOR. EMMPRIN was detected as high and low glycosylated forms in the OPM and OSCC cellular extracts and was released in the media by OSCC cells but not by OPM cells. EMMPRIN expression in an organotypic culture model of normal and OPM mucosae mirrored the expression patterns in the respective tissues in vivo. EMMPRIN expression was limited to basal cells of normal, benign hyperkeratotic and inflammatory (lichen planus) oral mucosa. EMMPRIN expression is increased in dysplastic leukoplakias spreading to more superficial layers, and its expression levels correlated significantly with the degree of dysplasia. Primary and metastatic OSCC showed strong cell surface expression of EMMPRIN. These results suggest that EMMPRIN overexpression occurs at a very early stage of oral carcinogenesis and plays a contributing role in OSCC tumorigenesis