Objectives:To study the radiographic location of the mental foramen and appearance of the inferior alveolar canal and the relationship between image gray values and the clarity of inferior alveolar canal on the digital panoramic images and to evaluate if the histogram equalization of the digital image would improve the visualization of the inferior alveolar canal outline on the digital panoramic images in the mandible. Methods:Five hundred digital panoramic images were evaluated by two examiners using a specific inclusion criteria. Only the right side of the mandible was studied. Chi-square analyses were used for comparisons of distributions. Mean and median pixel values were analyzed separately with a one-way analysis of variance. Also, percentages were calculated to report the usefulness of the histogram equalization for visualization of canal. Results: Results show variation in location of mental foramen.Most frequent location of the mental foramen was reported as first and second premolar region. Chi-square analysis showed that the frequency of occurrence of the mental foramen was equally probable for any of the three locations. The study did not find significant usefulness of the gray values obtained from the histogram equalization in predicting the clarity of inferior alveolar canal outlines.Clinical significance: Knowing the normal relationship and the anatomical variation of the maxillofacial structures for each patient is important for surgical implant treatment planning to avoid future complications. It is also important to be familiar with the advantages and limitations of diagnostic aids available before making treatment planning decisions based on such findings.

Background The nasopalatine canal (NPC) is of special importance when considering implant therapy in the maxillary central incisors' region. Purpose To investigate the incidence of NPC perforation in relation to virtual immediate implant placement. Materials and Methods A search through the cone beam computed tomography (CBCT) database of The University of Oklahoma—College of Dentistry was conducted. First, canal related measurements were conducted. Second, digital prosthetic planning was performed. Then, immediate implants were virtually placed and additional measurements were performed. Perforation rate was assessed. Last, data obtained was statistically analyzed. Results A total of 217 scans fulfilled the inclusion criteria. Only 8% of cases showed NPC perforation. The perforation occurred at mid‐third of the implant or at the mid and apical third in 33% and 22% of the cases, respectively. A statistically significant association was found between perforation of NPC and bone width palatal to the root of the central incisor (P < .0001) as well as canal angulation (P = .0196). NPC angulation (°) and palatal bone width (mm) predisposed to a higher risk of perforation. Only 27.78% of the perforations could be overcome by the installation of shorter implants. Conclusions Low incidence of NPC perforation could be expected when immediately placing implants in the maxillary incisor region.

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In this study, unenhanced digital imaging was found to be superior to conventional F-speed film and inversion-enhanced digital images for accurately imaging periodontal osseous defects in patients.

This study aims to characterize traumatic spinal cord injury (TSCI) neurophysiologically using an intramuscular fine-wire electromyography (EMG) electrode pair. EMG data were collected from an agonist-antagonist pair of tail muscles of Macaca fasicularis, pre- and post-lesion, and for a treatment and control group. The EMG signals were decomposed into multi-resolution subsets using wavelet transforms (WT), then the relative power (RP) was calculated for each individual reconstructed EMG sub-band. Linear mixed models were developed to test three hypotheses: (i) asymmetrical volitional activity of left and right side tail muscles (ii) the effect of the experimental TSCI on the frequency content of the EMG signal, (iii) and the effect of an experimental treatment. The results from the electrode pair data suggested that there is asymmetry in the EMG response of the left and right side muscles (p-value < 0.001). This is consistent with the construct of limb dominance. The results also suggest that the lesion resulted in clear changes in the EMG frequency distribution in the post-lesion period with a significant increment in the low-frequency sub-bands (D4, D6, and A6) of the left and right side, also a significant reduction in the high-frequency sub-bands (D1 and D2) of the right side (p-value < 0.001). The preliminary results suggest that using the RP of the EMG data, the fine-wire intramuscular EMG electrode pair are a suitable method of monitoring and measuring treatment effects of experimental treatments for spinal cord injury (SCI).