A)  Masseters are the strongest muscles of mastication in herbivores.
        "Function and Morphology of the Temporomandibular Joint According to Eating Habits" from Anatomical
        Atlas of the Temporomandibular Joint, Y. Ide, K. Nadazawa, Quintessence 1991
B)  In humans, the masseter is the second most efficient masticatory muscle, with a ratio of neurons to muscle fibers of 1:600.
        Carlsoo S: Motor units and action potentials in masticatory muscles.  Act Morphol Neerl-Scand.
        2:13-19; 1958
C)  The temporalis' % strength of maximal bite force is greatest when the mandible is open ~20 mm.
        Effect of jaw opening on the direction and magnitude of human incisal bite forces. Paphangkorakit J;
        Osborn JW, J Dent Res, 1997 Jan, 76:1,561-7
        See also:
           The effect of pressure on a maximum incisal bite force in man.
           Effects on human maximum bite force of biting on a softer or harder object.
D)  In carnivores  (those animals with prominent canine teeth) and in humans, the temporalis is the
      strongest and  most efficient muscle of mastication.  (A, above)  The ration of neuron to muscle
      fiber is 1:900.  (B above)
E)  When one lateral pterygoid positions the mandible excursively while the opposite temporalis
      contracts to stabilize the mandible, the isometric contraction of the lateral pterygoid can place
      significant strain on the isilateral TMJ. "Biomachics of the Masticatory System" from   Anatomical
      Atlas of the Temporomandibular Joint, Y. Ide, K. Nadazawa, Quintessence 1991
F)  Posterior, bilateral and equivalent occlusal contacts provide for maximal temporalis contraction
     intensity (clenching), and no strain on the TM joints (E above)
G)  A unilateral posterior occlusal contact allows for maximal temporalis contaction on the same side
     (E above)
H)  Since there is no stabilizing occlusal stop on the opposite side (G), that lateral pterygoid can
     contract and pull the condyle medially, toward the point of resistance, which is the unilateral
     posterior occlusal contact  (E above)  Hannam AG, "Musculoskeletal Biomechanics in the Mandible" in
    Current Controversies in Temporomandibular  Disorders, edited by Charles McNeil. Quintessence, 1991
I)   As the occlusal contact moves anteriorly to the canine, the potential maximum temporalis
    contaction intensity  decreases, but is still near maximal  Gibbs C, "EMG activity of the superior belly
     of the lateral pterygoid muscle in relation to other jaw muscles" J Pros Dent 1984, 51:691-701
J)  As the occlusal stop reaches the anterior midline, maximal temporalis contraction intensity is
     decreased by over 2/3s  Becker I, et al, "Effect of a prefabricated anterior bite stop on electromyographic
     activity of masticatory muscles" (graphic) J Pros Dent, 1999, 82:1, 22-6
K)  The direction of the force generated bilaterally by the lateral pterygoids is anterior, seating the
      condyles into  their most musculoskeletally stable position (E above)  Management of
      Temporomandibular Disorders and Occlusion. 2nd edition, p. 403. Okeson, JP. 1989 CV Mosby Co.
L)  Myofascial pain and dysfunction of the temporalis is described by Travell as "Temporal
      Headache",  and can be caused and/or perpetuated by chronic nocturnal intense temporalis
      contraction (i.e., clenching) Travell JG, Simmons DG: Myofascial Pain and Dysfunction, the Trigger
      Point Manual, Baltimore, 1983, Williams and Wilkens Co., Temporalis Chapter.
M)  Tension-type headache patients without signs or symptoms of TMD clench their jaws during
      sleep,  on average, 14 times more intensely than asymtomatic controls. Clark GT, et. al,
      Waking and sleeping temporalis EMG levels in tension-type headache patients   , J Orofac Pain, 1997
      Fall, 11:4, 298-306
N)  Spindle fibers reside within  muscles that oppose gravity, and serve primarily as stretch receptors.
      Rowlerson AM: Specialization of mammalian jaw muscles: fibre type compositions and the distribution of
      muscle spindles. In: Neurophysiology of the Jaws and Teeth (1-15). Taylor A es. London, 1990; Macmillan.
O)  When the needle EMG is moved only a few millimeters into a trigger point, EMG activity
      increases significantly  “Myofascial Trigger Points Show Spontaneous Needle EMG Activity”
      Hubbard, Berkoff,  SPINE,  Vol. 18 #13, pp1803-07, 1993
P)  In asymptomatic controls, when the needle EMG is placed into a "latent" trigger point (tender to
     palpation, but the patient reports no symptoms) and the subject is placed in a stressful situation
     (asked  to quickly count backwards by 13s, without mistakes), EMG activity of the intrafusal fibers
     increases significantly  “Needle electromyographic evaluation of trigger point response to a psychological
     stressor” McNulty, Hubbard, Gervitz, Berkoff.  Psychophysiology 31, 1994
Q) In patients with myofascial pain (a function of clenching) who use a splint, 1/3 of patients show no
     change, and 1/5 of patients get worse.  Clark G, “Nocturnal EMG evaluation of MPD in patients
     undergoing occlusal splint therapy” JADA, Vol. 99, October 1979
        See also:  Effect of muscle relaxation splint therapy on the electromyographic activities of masseter and
                   anterior temporalis muscles
R)  Ultimately, the occlusal scheme of a patient does not determine whether or not a person developes a temporomandibular disorder (K, page 160)
S)  The musclular activity is independant of the occlusal scheme. (Q)
T)  Treatment for myofascial pain  (headache) and TM disorders rarely resolve the signs and
     symptoms,  but serve  in the attempted management of the disorder (Q)  (K, entire book)
    ** Chronic sufferers see an average of 4.88 health care providers from 44 different categories for
         their  musculoskeletal facial pain  Turp JC, et al, "Treatment seeking patterns of facial pain patients;
         many  possibilities, limited satisfaction. J Orofac Pain, 1998 Win, 12:1, 61-6
U)  A functional role of the lower incisors is to monitor the hardness of food.  The more direct and
      intense the pressure, the more suppressed the closing activity.  Stohler CS, Ash MM: "Excitatory
      response of jaw elevators associated with sudden discomfort during chewing"  J  Oral Rhabil 13:225, 1986;
      Sessle BJ: in Roth GI, Calmes  R: Oral Biology, p. 61, The CV Crosby Co, St. Louis, 1981;
V)  The nociceptive trigeminal inhibition reflex (K, page 37)
W) A anterior, midline point stop has been advocated in fabrication of a full coverage splint, because
      of its demonstrated ability to reduce muscle contraction intensity and to allow the condyle to seat
      into its most favorable musculoskeletally stable position (K, page 403)
X)  As the jaw opens from a slightly discluded state to ~14mm, temporalis contraction intensity
      increases  (C)
Y)  Increasing the vertical dimension too far may result in destabilization of the cervical vertebrae (the patient
      may complain of a much more stiff and sore neck).

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