Temporomandibular disorders (TMD) are the name given to a group of conditions related to jaw movement and pain in and around the jaw joints1.  The temporomandibular joint is the hinge that connects a person’s jaw to the temporal bones of their skull, which are in front of each ear. It enables up and down and side to side movement of the jaw, enabling a person to talk, chew, and yawn2.

Many people have problems with jaw movement and pain in and around the jaw joints at some point during their lives1.

Simone* battled for years with what she assumed was bad sinus, as she would often experience headaches, sore blocked ears and suffer from exhaustion. It was only after a routine visit to her dentist that she was told that she was grinding her teeth badly, and was diagnosed with TMD.

One of the most common causes of TMD is muscle tension, often triggered by stress which can manifest in the clenching or grinding of teeth. This can tire the jaw muscles and lead to muscle spasm, tissue damage, pain, sore muscles, and more spasm1.

 Other possible causes include injuries to the jaw, joint or muscles of the head and neck (such as from whiplash) or any movement of the soft cushion between the ball and socket of the joint. Some people even suffer from arthritis in these joints which can also cause TMD2.

Dr Johan Hartshorne, a Cosmetic & Reconstructive Dental Surgeon from Cape Town, says that in his practice he sees a prevalence of TMD in about one out of every 20 patients. “Most patients present with jaw muscle spasm, ear ache, neck pain and difficulty chewing,” he says. Although less common, some patients even report a clicking sound of the jaw joint.

Other symptoms include2:

  • Pain or tenderness in the face, jaw joint area, neck and shoulders, and in or around the ear, especially when chewing, speaking, or  widely opening the mouth
  • A jaw that gets “stuck” or “locked” in the open- or closed-mouth position
  • A tired feeling in the face
  • Trouble chewing or a sudden uncomfortable bite – a feeling that the upper and lower teeth are no longer fitting together properly
  • Swelling on the side of your face

Dr Hartshorne says that most patients also present with advanced wearing away of the teeth and what he describes as a “loss of vertical dimension” due to the grinding of the teeth. “Many of these patients also present with some or other stressful situation in their life such as work or personal related problems,” he says.

Dr Hartshorne says that muscle relaxant and anti-inflammatory medication are the ideal first line of medication to relieve pain and symptoms in the short term.

Muscle relaxants, combined with a paracetamol analgesic, can provide effective relief of symptoms and can reduce muscular spasms and pain3, 4.  The Norflex®  range is the number one prescribed brand to relieve everyday painful musculoskeletal spasm5, 6.

How exactly does a muscle relaxant such as Norflex®  work? Orphenadrine citrate works centrally and interferes with reflex pathways for pain and skeletal muscle contraction7, 5. At the same time, paracetamol acts centrally and peripherally5 which provides effective pain control8.

Long term treatment can include having a bite plate fitted. This is usually a clear plastic mould that fits between the upper and lower teeth to reduce grinding and clenching1. Other treatments might include physiotherapy1 specific dental work, electrical nerve stimulation, ultrasound, injections or even as a last resort, surgery depending on the severity and cause of the TMD2.

For Simone*, her diagnosis brought with it a great sense of relief. It all finally made sense, as her symptoms were more noticeable during particularly stressful periods. She was prescribed Norflex Co® to assist with the short term relief of her symptoms and was fitted with a bite plate.


DISCLAIMER: This editorial has been commissioned and brought to you by iNova Pharmaceuticals. This editorial has content that includes independent comments and opinions from independent healthcare providers and are the opinions and experiences of that particular healthcare provider which are not necessarily that of iNova Pharmaceuticals. Content in this editorial is for general information only and is not intended to provide medical or other professional advice.


Scheduling status: S2 Proprietary name (and dosage form): NORFLEX CO Tablets. Composition: Each tablet contains 35 mg Orphenadrine citrate and 450 mg Paracetamol. Pharmacological classification: A.2.9 (Other analgesics). Reference number: B 1098 [Act 101/1965]; Scheduling status: S2 Proprietary name (and dosage form): NORFLEX Tablets. Composition: Each tablet contains 100 mg Orphenadrine citrate. Pharmacological classification: Category: A.2.10 (Centrally active muscle relaxants). Reference number: H1612. [Act 101/1965]. Scheduling status: S1 Proprietary name and dosage form: Norflex Gel. Composition: Each 100g contains: Benzydamine hydrochloride 3,0g. Pharmacological classification: A3.1 Antirheumatics (anti-inflammatory) agents. Registration number: 32/3.1/0547. Name and business address of applicant: iNova Pharmaceuticals (Pty) Ltd. Co. Reg. No.: 1952/001640/07. 15E Riley Road, Bedfordview. Tel. No.: 011 087 0000 www.inovapharma.co.za. For full prescribing information, refer to the package insert as approved by the MCC (Medicines Control Council). Further information is available on request from iNova Pharmaceuticals. IN2695/18


  1. Healthlink British Columbia – Temporomandibular Disorders (TMD). 7 May 2017 (https://www.healthlinkbc.ca/health-topics/hw209469). Website accessed on 13 February 2018
  2. WEB MD – Temporomandibular Joint Disorders (TMD, TMJ) (https://www.webmd.com/oral-health/guide/temporomandibular-disorders-tmd#1)
  3. Hunskaar S, Donnell D. Clinical and Pharmacological. Review of the Efficacy of Orphenadrine and Its Combination with Paracetamol in Painful Conditions. J Int Med Res 1991;19:71-87.
  4. McGuinness BW. A Double-Blind Comparison in General Practice of a Combination Tablet Containing Orphenadrine Citrate and Paracetamol (‘Norgesic’) with Paracetamol Alone. J Int Med Res 1983;11(1):42-45.
  5. Waldman HJ. J Pain Symptom Manage 1994; 9(7):434-441.
  6. Impact Rx. Script Data – October 2017.
  7. Hunskaar S, Donnell D. Clinical and Pharmacological Review of the Efficacy of Orphenadrine and Its Combination with Paracetamol in Painful Conditions. J Int Med Res 1991;19:71-87.
  8. NSW Government Nurse Practitioner Clinical Practice Guidelines Feb 2006.