CMT Oral Habits & Parafunctional Behaviors 2 — Questions and Answers
Question 1: Which parafunctional habit is most strongly associated with temporomandibular joint (TMJ) disorders and myofascial pain?
- Digit sucking
- Tongue thrusting
- Bruxism (teeth grinding/clenching) (Correct answer)
- Lip biting
Correct answer: Bruxism (teeth grinding/clenching)
Bruxism generates excessive repetitive forces on the TMJ and masticatory muscles, making it the parafunctional habit most closely linked to TMJ disorders and myofascial pain.
Question 2: What is the primary orofacial development concern when pacifier use continues beyond age 2?
- Increased risk of dental caries
- Malocclusion, particularly anterior open bite and posterior crossbite (Correct answer)
- Delayed speech sound acquisition
- Temporomandibular joint inflammation
Correct answer: Malocclusion, particularly anterior open bite and posterior crossbite
Prolonged pacifier use beyond age 2 is primarily associated with anterior open bite and posterior crossbite due to continuous mechanical pressure on the developing dental arches.
Question 3: Habitual lower lip biting or sucking most commonly produces which dental finding?
- Posterior crossbite
- Proclination of maxillary incisors and retroclination of mandibular incisors (Correct answer)
- Class III skeletal tendency
- Posterior open bite
Correct answer: Proclination of maxillary incisors and retroclination of mandibular incisors
Habitual lower lip sucking traps the lower lip behind the upper incisors, pushing upper teeth forward (proclination) and tipping lower teeth backward (retroclination).
Question 4: Which behavioral modification technique is most commonly recommended as first-line treatment for thumb sucking in cooperative children?
- Fixed palatal habit reminder appliance
- Positive reinforcement with reward charts (Correct answer)
- Aversive taste therapy (bitter nail coating)
- Occlusal splint during sleep
Correct answer: Positive reinforcement with reward charts
Positive reinforcement through reward charts and praise is the recommended first-line behavioral approach for habit elimination in cooperative children, supporting intrinsic motivation before more invasive methods.
Question 5: A palatal crib or 'hay rake' appliance is primarily designed to interrupt which oral parafunctional habit(s)?
- Bruxism
- Lip biting
- Tongue thrusting and thumb/digit sucking (Correct answer)
- Cheek biting
Correct answer: Tongue thrusting and thumb/digit sucking
The palatal crib is a fixed or removable orthodontic appliance that physically blocks digit access and eliminates the suction reward while simultaneously interrupting forward tongue thrust.
Question 6: Chronic mouth breathing as a parafunctional resting pattern most commonly leads to which orofacial change?
- Widening of the maxillary arch
- Narrowing of the maxillary arch with a high-vaulted palate (Correct answer)
- Anterior mandibular prognathic growth
- Decreased nasal airway resistance
Correct answer: Narrowing of the maxillary arch with a high-vaulted palate
Chronic mouth breathing removes normal tongue pressure from the palate, allowing buccal muscles to narrow the maxillary arch and promote development of a high-arched palatal vault.
Question 7: The term 'interdental tongue posture at rest' refers to which condition?
- Tongue placement touching the upper posterior molars
- The tongue resting between the upper and lower anterior teeth (Correct answer)
- The tongue pressed firmly against the entire hard palate
- Posterior tongue elevation during phonation
Correct answer: The tongue resting between the upper and lower anterior teeth
Interdental tongue posture at rest describes the tongue lying between the upper and lower anterior teeth as a resting position, which can perpetuate or worsen an anterior open bite.
CMT Oral Habits & Parafunctional Behaviors 2
Which parafunctional habit is most strongly associated with temporomandibular joint (TMJ) disorders and myofascial pain?