Professionals performing radiographic examinations are responsible for maintaining optimal image quality for accurate diagnoses. These professionals must competently execute techniques such as film manipulation and processing to minimize patient exposure to radiation. Improper performance by the professional and/or patient may result in a radiographic image of unsatisfactory quality that can also lead to a misdiagnosis and the development of an inadequate treatment plan. Currently, the most commonly performed extraoral examination is panoramic radiography. The invention of panoramic radiography has resulted in improvements in image quality with decreased exposure to radiation and at a low cost. However, this technique requires careful, accurate positioning of the patient's teeth and surrounding maxillofacial bone structure within the focal trough. Therefore, we reviewed the literature for the most common types of positioning errors in panoramic radiography to suggest the correct techniques. We would also discuss how to determine if the most common positioning errors occurred in panoramic radiography, such as in the positioning of the patient's head, tongue, chin, or body.

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Orofacial pain is a prevalent symptom in modern society. Some musculoskeletal orofacial pain is caused by temporomandibular disorders (TMDs). This condition has a multi-factorial etiology, including emotional factors and alteration of the masticator muscle and temporomandibular joints (TMJs). TMJ inflammation is considered to be a cause of pain in patients with TMD. Extracellular proteolytic enzymes, specifically the matrix metalloproteinases (MMPs), have been shown to modulate inflammation and pain. The purpose of this investigation was to determine whether the expression and level of gelatinolytic activity of MMP-2 and MMP-9 in the trigeminal ganglion are altered during different stages of temporomandibular inflammation, as determined by gelatin zymography. This study also evaluated whether mechanical allodynia and orofacial hyperalgesia, induced by the injection of complete Freund's adjuvant into the TMJ capsule, were altered by an MMP inhibitor (doxycycline, DOX). TMJ inflammation was measured by plasma extravasation in the periarticular tissue (Evans blue test) and infiltration of polymorphonuclear neutrophils into the synovial fluid (myeloperoxidase enzyme quantification). MMP expression in the trigeminal ganglion was shown to vary during the phases of the inflammatory process. MMP-9 regulated the early phase and MMP-2 participated in the late phase of this process. Furthermore, increases in plasma extravasation in periarticular tissue and myeloperoxidase activity in the joint tissue, which occurred throughout the inflammation process, were diminished by treatment with DOX, a nonspecific MMP inhibitor. Additionally, the increases of mechanical allodynia and orofacial hyperalgesia were attenuated by the same treatment.

Background and Purpose l‐DOPA‐induced dyskinesia is a debilitating effect of treating Parkinson's disease with this drug. New therapeutic approaches that prevent or attenuate this side effect are needed. Experimental Approach Wistar adult male rats submitted to 6‐hydroxydopamine‐induced unilateral medial forebrain bundle lesion were treated with l‐DOPA (p.o. 20 mg·kg−1 or s.c. 10 mg·kg−1) once a day for 14 days. After this period, we tested if doxycycline (40 mg·kg−1, i.p.) and COL‐3 (50 and 100 nmol, i.c.v.) could reverse l‐DOPA‐induced dyskinesia. In an additional experiment, doxycycline was administered together with l‐DOPA to verify if it would prevent l‐DOPA‐induced dyskinesia development. Key Results A single injection of doxycycline or COL‐3 attenuated l‐DOPA‐induced dyskinesia. Co‐treatment with doxycycline from the first day of l‐DOPA suppressed the onset of dyskinesia. The improved motor response after l‐DOPA was not affected by doxycycline or COL‐3. Doxycycline treatment was associated with decreased immunoreactivity of FosB, COX‐2, the astroglial protein GFAP and the microglial protein OX‐42, which were elevated in the basal ganglia of rats exhibiting dyskinesia. Doxycycline decreased metalloproteinase‐2/‐9 activity, metalloproteinase‐3 expression and ROS production. Metalloproteinase‐2/‐9 activity and production of ROS in the basal ganglia of dyskinetic rats showed a significant correlation with the intensity of dyskinesia. Conclusion and Implications The present study demonstrates the anti‐dyskinetic potential of doxycycline and its analogue compound COL‐3 in hemiparkinsonian rats. Given the long‐established and safe clinical use of doxycycline, this study suggests that these drugs might be tested to reduce or prevent l‐DOPA‐induced dyskinesia in Parkinson's patients.