what is NTI
TMD, bruxism, chronic tension headaches, migraine ...
Have you ever wondered what these symptoms have in common? all of which make your patient's life miserable
What exactly is the nociceptive trigeminal inhibition reflex ?
The direct stimulation of the periodontal ligament (PDL) of the lower incisors activates a feedback loop, which significantly limits the contraction intensity of the trigeminus muscle (adversely, anesthesia of the same PDL of the lower incisors will enable an increase in the contraction of the temporalis muscle).
Try it yourself :
Take a pencil and place it between your molars or canines. With your hands feel the temporalis muscle bulge in the temple area.
Then transfer the pencil between your incisors and palpate the temporalis at the same spot on your temples again : do you feel the difference ?
Studies show that the possible contraction intensity of the temporalis muscle when only the incisors occlude is reduced by an average of 70%!

During sleep the contraction intensity of the temporalis muscle increases
In a study by Clark GT, et. al, (Journal of Orofacial Pain, Fall 1997) tension-type headache patients without signs or symptoms of TMD clenched their jaws during sleep, on average, 14 times more intensely than asymptomatic controls !
Moreover it has been shown, that temporalis contraction is twice as intense during sleep than in waking patients.

Source : Lous /Olesen 1982 - "Evaluation of pericranial tenderness and oral function in patients with migraine, muscle contraction headache and combination headache".
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Dr. Boyd, Founder of NTI-tssDr. Boyd founded the Headache Prevention Institute in Bloomfield Hills, Michigan in 1995, and through 1999 exclusively treated patients suffering from chronic tension-type headache, migraine, and jaw disorders. Dr. Boyd is currently Director of Research and Clinical Instructor at the White Memorial Medical Center Craniofacial/TMD clinic in Los Angeles. Dr. Boyd also practices in Solana California, and lectures throughout the U.S. and internationally. |
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Dr. Helen M C Harrison
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Dr. Andre Hedger
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Indications for the NTI-tss
All cases requiring a disconnection of the occlusion and/or the relaxation of the masticatory musculature such as
- the prevention of symptoms associated with bruxism
- the treatment of certain types of TMD
- the prevention of occlusal trauma, e.g. protection of restorations and implants in cases of severe bruxism
- the prevention and treatment of chronic tension type headache and migraine pain
Advantages of the NTI-tss
- Excellent clinical results
- Extremely simple and fast chair side procedure: fabrication in 20 minutes; no delays or lab fees
- Excellent patient acceptance and compliance
- High diagnostic value
- Scientifically proven efficacy


