Background Bone remodeling is a lifelong process that ranges from orthodontic tooth movement/alignment to bone damage/healing, to overall bone health. Osteoprotegerin (OPG) and transforming growth factor β1 (TGF-β1) are secreted by osteoblasts and participate in bone remodeling. OPG promotes bone remineralization and stabilization prominent in post-mechanical repositioning of the teeth in the dental alveolus. TGF-β1 participates in regulatory processes to promote osteoblast and osteoclast equilibrium. In the context of orthodontic tooth movement, post-treatment fixation requires additional, exogenous, stabilization support. Recent research showcases supplementary solutions, in conjunction to standard tooth fixation techniques, such as OPG injections into gum and periodontal tissues to accelerate tooth anchorage; however, injections are prone to post-procedure complications and discomfort. This study utilizes noninvasive bioelectric stimulation (BES) to modulate OPG and TGF-β1 as a novel solution to regulate bone remineralization specifically in the context of post-orthodontic tooth movement. Purpose The aim of this study was to investigate a spectrum of BES parameters that would modulate OPG and TGF-β1 expression in osteoblasts. Methods Osteoblasts were cultured and stimulated using frequencies from 25 Hz to 3 MHz. RT-qPCR was used to quantify changes in OPG and TGFb-1 mRNA expression. Results OPG mRNA expression was significantly increased at frequencies above 10,000 Hz with a maximum expression increase of 332 ± 8% at 100 kHz. Conversely, OPG mRNA expression was downregulated at frequencies lower than 1000 Hz. TGF-β1 mRNA expression increased throughout all stimulation frequencies with a peak of 332 ± 72% at 250 kHz. Alizarin Red tests for calcium, indicated that mineralization of stimulated osteoblasts in vitro increased 28% after 6 weeks in culture. Discussion Results support the working hypothesis that OPG and TGF-β1 mRNA expression can be modulated through BES. Noninvasive BES approaches have the potential to accelerate bone remineralization by providing a novel tool to supplement the anchorage process, reduce complications, and promote patient compliance and reduce post-treatment relapse. Noninvasive BES may be applicable to other clinical applications as a novel therapeutic tool to modulate bone remodeling.

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PURPOSE: Class III dentofacial deformities are growthrelated deformities characterized by deficiency of the maxilla and/or a prognathic mandible. Three approaches to the correction are growth modification, orthodontic camouflage, and surgery. Traditional Orthodontic treatment for maxillary deficiency is protraction of the maxilla with reverse pull headgear or facemasks. Posterior rotation of the mandible and an unaesthetic increased vertical dimension of the face can result. Camouflage is an option depending on the patient's aesthetic desires, but will not correct the facial deformity. Surgical treatment involves Le Fort I advancement alone or in combination with BSSO set-back. A newer approach involves manipulating the immature facial skeleton by way of bone anchored maxillary protraction. This method uses growth modification with the assistance of a minor surgical procedure attempting to avoid a future major surgical procedure. We evaluated this method using miniplates in patients with class III skeletal relationships: METHODS:A retrospective chart review to identify patients who had been treated with placement of bollard plates for class III skeletal malocclusion. Data was collected from lateral cephalograms and exams. RESULTS:CONCLUSION: Our results demonstrate this method was effective at normalizing the maxillomandibular relationship in these patients without deleteriously affecting facial aesthetics. Bone anchored maxillary protraction with miniplates appears to offer an alternative to both reverse pull headgear & possibly future orthognathic surgery for the treatment of class III dentofacial deformities. PURPOSE:Many surgical techniques for lambdoidal synostosis have been described, but there remains no clear best practice when it comes to surgical management. Current methods range from complete posterior calvarial reconstruction to distraction techniques. METHODS:A retrospective review was performed on one surgeon's experience with craniosynostosis between the years of 1994 and 2014. Out of six hundred and sixty-four cases of craniosynostosis, twenty-two primarily involved the lambdoidal suture, a rate of 3.3%. Twenty-one were repaired using a novel "tongue and groove" technique. RESULTS:Of the twenty-two patients, nineteen were unilateral and three were bilateral. Male-to-female ratio was found to be 3:1. The average age of first craniofacial physician encounter was thirty-four weeks (8.5 months) Average age at time of surgery was forty-three weeks (10.75 months). Of the twenty-two patients, twenty-one had the unilateral tongue and groove technique described in this paper. The average surgical time for just the posterior calvarial reconstruction was 142 minutes with an average blood loss of 178 ml with a 95% blood transfusion rate. Complications included one patient who experienced re-fusion of his lambdoidal suture and fusion of his sagittal suture, another who returned for redo-anterior calvarial reconstruction, and four who returned for bone graft coverage of full-thickness calvarial defects due to a...

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