Orthodontic tooth movement (OTM) causes transient pain and changes in the dental occlusion that may lead to altered somatosensory inputs and patterns of mastication. This study used intracortical microstimulation (ICMS) and electromyographic (EMG) recordings to test whether neuroplastic changes occur in the ICMS-defined motor representations of left and right anterior digastric (LAD, RAD), masseter, buccinator, and genioglossus (GG) muscles within the rat's face primary motor cortex (face-M1) and adjacent face primary somatosensory cortex (face-S1) during OTM. Analyses included any changes in the number of ICMS sites representing these muscles and in the onset latencies of ICMS-evoked responses in the muscles. Sprague-Dawley rats were divided into experimental (E), sham (S), and naive (N) groups; OTM was induced in the E group. Statistical analyses involved a mixed model repeated-measures analysis of variance (MMRM ANOVA). OTM resulted in significant neuroplastic changes in the number of positive sites in the E group for LAD, RAD, and GG muscles in face-M1 and face-S1 at days 1, 7, and 28 of continuous orthodontic force application, and in the number of sites in face-M1 from which ICMS could simultaneously evoke EMG responses in different combinations of LAD, RAD, and GG muscles. However, the onset latencies of ICMS-evoked responses were not significantly different between groups or between face-M1 and face-S1. The neuroplastic changes documented in this study may reflect adaptive sensorimotor changes in response to the altered environment in the oral cavity induced by OTM.

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Purpose To present 3 cases of an unusual soft tissue lesion in infants with clinicopathological correlation. Methods Case 1: A 2‐year‐old boy presented with a rapid growing lesion in his right lateral orbit. Case 2: A 5‐year‐old girl with a left superior orbital lesion close to lacrimal sac. Both cases had clinical appearances of a dermoid and excision was performed. Case 3: A 1‐year‐old boy presented with a 6 week history of an enlarging right medial canthal mass. CT scan showed a greatly expanded nasolacrimal duct. Endoscopy revealed a polypoid lesion and multiple biopsies were taken. Results The specimens from cases 1 and 2 consisted of firm nodular tissue measuring up to 30 and 18mm in diameter respectively. Several biopsies (2‐6mm) were submitted from case 3. In all cases histology showed plump spindle cells arranged in interweaving fascicles in a collagenous stroma. Variable amount of myxoid change was present. There was no necrosis or mitotic activity. Diffuse SMA and focal CD68 positivity were encountered. Negative markers were: CD34, S100, neurofilament, desmin, MyoD1 and myogenin. The overall features were those of a nodular fasciitis. Conclusion Only four cases of orbital nodular fasciitis have been reported in children younger than 5 years. We report a series of further three cases in this age group, two masquerading as a dermoid, raising the awareness of this entity as a clinical differential diagnosis of rapidly growing lid/orbital lesions in infants.

Brown's tumor is a benign bone lesion that occurs in the setting of hyperparathyroidism and can affect the facial skeleton. It often presents as a single lesion and is usually less than 3 centimeters. To our knowledge, no cases have been reported to have bilateral involvement of the maxilla and mandible with the largest dimension measuring over 7 centimeters. This report describes such a case and provides a review of the literature.