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Funding Opportunities now available for the NIH Common Fund’s Acute to Chronic Pain Signatures program

The NIH Common Fund's Acute to Chronic Pain Signatures program aims to understand the biological characteristics underlying the transition from acute to chronic pain and what makes some people susceptible and others resilient to the development of chronic pain.

Opportunity to Voice Your Opinion: U.S. Government Officials Want To Hear from Patients with Pain

FDA Public Meeting on Patient-Focused Drug Development for Chronic Pain On July 9, 2018, FDA hosted a public meeting on Patient-Focused Drug Development for Chronic Pain. https://www.federalregister.gov/documents/2018/05/15/2018-10284/patient-focused-

Consider Including the TMJA in Your Financial Planning

We were recently contacted by Tom P. who informed us that he was including The TMJ Association (TMJA), in his financial planning. Tom wrote the following for us to share with our readers:

The Scoop on TMD Pharmaceuticals

Let's say the National Institutes of Health just handed us a multi-million dollar grant to get to the bottom of TMD and find a cure once and for all. I mean, we could start handing out heating pads left and right, but that kind of relief can only get us so far. Whenever I try a different form of therapy or medication, I like to think about the biology, right down to the cellular and molecular level. Why are the cells that make up my jaw region being such jerks?

Join Us AT TMJ Cafe

The TMJ Association is pleased to partner with Inspire to bring you the TMJ Cafe, a free online support network and discussion community for those with Temporomandibular Disorders (TMD). We invite you to meet others like you, share experiences and tips for getting through the day, and give and receive support.

Early Molecular Response and Microanatomical Changes in the Masseter Muscle and Mandibular Head After Botulinum Toxin Intervention in Adult Mice

  • May 30, 2018

We thank Dr. Susan Herring for providing our readers with this research summary. 

In this small study, young adult mice received an injection of Botox in the right masseter muscle, while the left masseter received the same volume of saline as a control. The authors examined gene expression in the mandibular condyles 2 days after the injections and in the muscles 7 days after the injections. Two weeks after the injections, they looked for structural changes in the condyles and masseters.

The results showed dramatic early changes in gene expression. Only 2 days after treatment, the Botox side condyles showed four times as much activity in a gene that promotes bone resorption (RankL) than the saline side condyles. The Botox-injected masseters had greatly increased expression of genes involved in muscle atrophy at the 1 week time point compared to the control side muscles. At the end of the study, 2 weeks after injection, the Botox-injected masseters were about 20% smaller than the control side masseters, and the Botox-side condyles had lost about 40% of relative bone area compared to the control side condyles.

This study is preliminary in many ways. Sample size was very small and only included male mice of one inbred strain. Each outcome was measured at just one time point. The findings that Botox treatment of the masseter cause atrophy of the paralyzed muscle and severe loss of bone in the TMJ region are not new. Nevertheless, the study illustrates how rapidly the tissues react to treatment with this powerful toxin. It is striking that bone loss in the condyles was already triggered by the second day, because this bone loss is likely not a direct effect of the toxin, but rather a response to the absence of muscle loading.

From the point of view of The TMJ Association, important questions that remain include (1) does the bone of the condyle eventually recover, and if so, how long does it take? and (2) does the loss of condylar bone threaten the integrity of the TMJ and make it more vulnerable to injury? To date, there are no studies that address these questions in either animals or humans.

Source: Balanta-Melo J, Toro-Ibacache V, Torres-Quintana MA, Kupczik K, Vega C, Morales C, Hernández-Moya N, Arias-Calderón M, Beato C, Buvinic S. Early molecular response and microanatomical changes in the masseter muscle and mandibular head after botulinum toxin intervention in adult mice Ann Anat. 2018 Mar;216:112-119. doi: 10.1016/j.aanat.2017.11.009. Epub 2017 Dec 28. 

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