Etiology of Malocclusion MCQs – Orthodontics MCQs (Dental Pulse)
1. Retained mandibular deciduous central incisors will result in
a) Lingual eruption of mandibular permanent incisors
b) Labial eruption of mandibular permanent incisors
c) Impaction of mandibular permanent incisors
d) Ankylosis of mandibular permanent incisors
2. The most common local cause of malocclusion is
a) Premature exfoliation of deciduous maxillary central incisors
b) Prolonged retention of primary teeth
c) Ankylosis of permanent teeth
d) Impaction of permanent teeth
3. The most common cause of maxillary central incisor to be in cross-bite is
a) Premature exfoliation of deciduous maxillary central incisors
b) Prolonged retention of deciduous maxillary central incisors
c) High labial frenum
d) Early loss of deciduous mandibular
4. Tooth in the mandibular arch which is most likely to be displaced due to arch size discrepancy is
a) First molar
b) Second molar
c) First premolar
d) Second premolar
5. Which one of the following has maximum familial tendency?
a) Protruded maxillary incisors
b) Open bite
c) Deep bite
d) Upper and lower cross bite.
6. The cause of pseudoclass III malocclusion is:
a) Developmental deficiency
b) Increased mandibular growth
c) Functional abnormality
d) Hormonal disturbance
7. Mouth breathing with enlarged adenoids and tonsils may be best described as:
a) Anatomic
b) Obstructive
c) Physiologic
d) Habitual
8. A child who had a congenital defect of cleft lip and cleft palate is most likely to suffer from which kind of malocclusion
a) Bilateral posterior cross bite (Due to maxillary constriction and collapse, a common sequel of cleft palate.)
b) A collapsed anterior mandibular arch
c) Protrusion and spacing of maxillary anterior teeth
d) Class II division I malocclusion
9. Acromegaly is associated with:
a) Class. I malocclusion
b) Class. I cross bite
c) Class. II malocclusion
d) Class. III malocclusion (Acromegaly involves excessive growth hormone in adulthood, often leading to mandibular prognathism.)
10. Abnormally thick maxillary labial frenum results in
a) Maxillary Midline diastema
b) Imbrication of incisors
c) Labial inclination of incisors
d) Anterior deep bite
11. The abnormal swallowing pattern with the poorest prognosis is:
a) Simple tongue thrust
b) Complex tongue thrust
c) Infantile swallow
d) Retained infantile swallow
12. Treatment of diastema because of a thick labial frenum is done:
a) After frenectomy
b) Before eruption of canines
c) After eruption of canines (The canines provide root convergence to help close the space; frenectomy is often done after space closure.)
d) Before frenectomy
13. The most probable cause of crowding in lower anterior region is:
a) Prolonged retention of lower primary incisors
b) Premature exfoliation of lower primary incisors
c) Presence of supernumerary teeth
d) Tooth-size-arch length discrepancy (This is the fundamental underlying cause of most crowding.)
14. Prolonged retention of primary tooth may lead to
a) Altered path of permanent tooth eruption
b) Root resorption of adjacent tooth
c) Ankylosis of permanent tooth
d) Warping of roots of adjacent teeth
15. A child is brought to the clinic with complaint of irregular teeth. The maxillary central incisor is rotated in an otherwise normal occlusion. What should the next step be?
a) Check for supernumerary teeth (A rotated central incisor can be a key sign of an obstructing supernumerary tooth, like a mesiodens.)
b) Resection of supracrestal fibers
c) Exert a couple on tooth
d) Fixed orthodontic appliances given
16. A malocclusion is characterized by protrusion of maxilla, labioversion of maxillary incisors deep overbite and overjet. These are typical characteristic of which malocclusion
a) Class I
b) Class II Div 1
c) Class II Div 2
d) Class III
17. A 9-year-old patient exhibits left maxillary central incisor in cross bite. Supporting bone is in harmony with tooth size. The most probable cause is:
a) Premature extraction of primary right central incisor
b) Prolonged retention of primary left central incisor (A common local cause for a single tooth crossbite.)
c) Absence of mandibular left central incisor
d) All of the above
18. The most common cause of class II malocclusion
a) Sleeping habits
b) Growth discrepancy (Skeletal Class II is primarily due to a mandibular deficiency or maxillary excess.)
c) Thumb and tongue thrusting
d) Tooth to jaw size discrepancy.
19. Bruxism bears which one of the following relationships to malocclusion
a) Malocclusion is only cause of bruxism
b) Malocclusion may be the cause of bruxism (Malocclusion is one potential contributing factor among many, like stress.)
c) Correction of occlusal discrepancy always eliminate bruxism
d) None of above
20. A 10 year-old patient with class II relationship stops thumb – sucking
a) Over-jet will decrease
b) Upper incisors will become up right
c) There will be crowding of the lower incisors
d) A and B (Stopping the habit allows for spontaneous improvement of the dentoalveolar effects: reduced overjet and uprighting of proclined incisors.)
21. Which of the following is not a features of simple tongue thrust swallowing
a) Contraction of facial muscle
b) Contraction of mandibular elevators
c) Teeth apart swallow
d) Anterior open bite
22. The oral drive theory to explain thumb sucking habit was given by
a) Benjamin
b) Sears and wise
c) Sigmund freud
d) Scheldon
23. Abnormal muscle activity results in
a) Bruxism
b) nail biting
c) Tongue thrusting (Tongue thrust is primarily a myofunctional disorder involving abnormal muscle activity.)
d) thumb sucking
24. In adenoid facies, the facial profile is
a) Long and wide
b) Long and narrow (Characterized by a long, narrow face, mouth breathing, and narrow nose.)
c) Short and wide
d) Short and narrow
25. Which of the following statements is False
a) Heredity plays an important role in the development of normal occlusion.
b) A tongue thrusting habit may cause an open bite
c) Mouth breathing is a recognized contributing cause of malocclusion
d) The cuspids are the most useful teeth for the anchorage of appliances (Molars, not canines, are typically the primary teeth used for anchorage due to their larger root surface area.)
26. In the pre-school stage what % of the children show thumb-sucking
a) Less than 10%
b) 10-20%
c) More than 50% (Thumb sucking is very common in infants and preschoolers.)
d) all children
27. Rooting reflex disappears in normal infants by the age of
a) 4 months after birth
b) 7 months after birth
c) 9 months after birth
d) 12 months after birth
28. Earnest Klein has classified habits into
a) Compulsive and non-compulsive habits
b) Intentional and non-intentional habits
c) Primary and secondary habits
d) Pressure and non-pressure habits
29. Breathing is termed anatomic mouth breathing if
a) Short upper lip
b) Enlarged Adenoid
c) Enlarged Tonsil
d) Both A and B (Anatomic causes include short upper lip and airway obstructions like enlarged adenoids.)
30. The positioning of tongue in infantile swallowing is
a) Posterior
b) Medial
c) Lateral
d) Anterior (The tongue is thrust forward against the lips to form a seal.)
31. The patients with class II division 1 malocclusion have
a) Hypertonic lower lip
b) Hypotonic lower lip
c) Hypertonic upper lip
d) Hypotonic upper lip
32. In thumb-sucking habit, posterior cross bite occurs due to
a) Loss of normal outward thrust of the tongue
b) Negative pressure within the oral cavity, which causes buccinator to force the maxillary molar palatally
c) A & B
d) Loss of oral seal
33. Lalloo, a 13-year old child has a severe thumb-sucking habit. On examination he has a Class-II malocclusion, anterior open bite with an over-jet of 12mm. His cephalogram will show:
a) Normal anterior and posterior facial heights
b) Increased anterior facial height and normal posterior facial height (A long-face pattern with increased lower facial height is common with prolonged thumb sucking.)
c) Increased posterior facial height and normal anterior facial height
d) Increased posterior facial height and increased anterior facial height
34. The effect of enlarged Adenoids on the maxillary growth is by
a) Narrowing of maxilla (Adenoids can contribute to mouth breathing, leading to a narrow, high-vaulted palate.)
b) Widening of maxilla
c) Palatal plane tipped upwards at PNS
d) Palate descends down
35. Which of the cephalometric parameter is used to diagnose a long face syndrome patient?
a) ANB angle
b) SNA angle
c) Jaraback ratio (This ratio compares posterior and anterior facial heights; a reduced ratio indicates a long face.)
d) Saddle angle
36. More than 80% cephalic index of a patient indicates which of the following
a) Brachycephalic (Cephalic Index = (head width/head length) x 100. >80% is brachycephalic (short, broad head).)
b) Mesocephalic
c) Dolicocephalic
d) Depends on age
37. Soft tissue profile of a thumbsucking patient is
a) convex (Due to proclined maxillary incisors and often a retrusive chin.)
b) concave
c) normal
d) anterior divergent
38. Relative to a heterogenous population, the incidence of malocclusion in a homogenous population generally is:
a) Lower (Less genetic and ethnic variation often leads to a more uniform and ideal occlusion.)
b) Slightly higher
c) Significantly higher
d) About the same
39. The supervision of a child’s development of occlusion is most critical at ages?
a) 3 – 6 years
b) 7 – 10 years (This encompasses the early and late mixed dentition period, a crucial time for intervention.)
c) 11 – 14 years
d) 14 – 17 years
40. Anterior openbite & maxillary constriction is caused by:
a) Thumb sucking (The thumb acts as an obstructive force, preventing incisor eruption and applying a transverse force that constricts the maxilla.)
b) Nail biting
c) Bruxism
d) Lip biting
41. The most common variant of malocclusion seen is:
a) Angle’s class-I occlusion with anterior crowding (Class I malocclusion with crowding is the most prevalent type.)
b) Angle’s class-I occlusion with posterior crowding
c) Angle’s class-II div I
d) Angle’s class-II div II
42. A patient is involved in chronic mouth breathing, the clinical examination of the patient reveals.
a) Convex profile, long face, narrow arches (Classic “adenoid facies” or long-face syndrome features.)
b) Concave profile, long face, broad arches
c) Convex profile, short face, broad arches
d) Concave profile, short face, narrow arches
43. Which of the following is the most common orofacial malformation that produces malocclusion?
a) Cleft lip and palate
b) Ectodermal dysplasia
c) Pierre Robin syndrome
d) Osteogenesis imperfecta
44. Which of the following are NOT associated with complex tongue thrusting activity?
a) Naso-respiratory distress
b) Contraction of the temporalis muscle (Complex tongue thrust is associated with a lack of strong elevator muscle contraction during swallow.)
c) Contraction of the mentalis and lower lip during swallow
d) Absence of contact of teeth during swallow
45. A 6 year old female child reported with a chief complaint of proclined upper anteriors. Parents give a history of prolonged bottle-feeding and a persistent thumb sucking habit. Clinical examination reveals anterior open bite with proclined upper anterior and retrocined lower anterior teeth and associated tongue thrusting.
A) In thumb sucking protraction of the maxillary teeth is seen when
a) When the pollex is held upward against the palate (The upward pressure against the palate leads to maxillary anterior proclination.)
b) When the pollex is held downward against the tongue
c) When the pollex is held inward against the cheek
d) None of the above
B) The foremost line of treatment in this patient is
a) No treatment. Wait and watch
b) Extraction of first premolars followed by Hawleys appliance
c) Psychiatric consultation prior to any therapy (For a 6-year-old, addressing the psychological component of the persistent habit is the first step.)
d) Extraction of second premolars followed by Hawleys appliance
C) The tongue thrust seen in this case is
a) Retained Infantile swallow
b) Simple tongue thrust (An adaptive tongue thrust secondary to the anterior open bite created by thumb sucking.)
c) Complex tongue thrust
d) Compound tongue thrust
D) Usually digit sucking habits are outgrown by
a) 6-7 yrs
b) 3-4 Yrs (Most children stop spontaneously between ages 2-4.)
c) 1-2 yrs
d) 11-12 yrs
46. A 5-year-old residential school child walks in to your clinic with the habit of thumb sucking in association with bruxism
A) What would be probable cause
a) Food habits
b) Nasal septal deviation
c) Habitual
d) Psychological (Common in children in new/stressful environments like boarding school.)
B) Usually sucking digit will be having
a) Fibrous roughened callus (Chronic friction causes hyperkeratosis and a callus.)
b) Laceration of digit
c) Cut wound on digit
d) Long finger balls
C) Chemical approach for reminder therapy is
a) Fem
b) Femite (A bitter-tasting commercial product applied to the thumb.)
c) Nail polish
d) Nail polish with flavor
D) Following effects are seen on maxilla except
a) Increased SN to ANS – PNS angle (This angle would decrease (palatal plane rotates clockwise) due to posterior maxillary downward growth from thumb pressure.)
b) Increased proclination
c) Increased maxillary arch length
d) Increased SNA
47. Malocclusion can be progressive in:
a) Class I
b) Class II
c) Class III (Class III malocclusions, especially those with a mandibular growth excess, often worsen with age.)
d) Combination of both A&C
48. A 21 year old male healthy patient reported with a prognathic mandible, intraorally he has anterior crossbite and class III molar relationship, cephalometrically has an SNA of 78 degrees, SNB of 89 degrees
48A. What would be the treatment of choice for the adult class III skeletal malocclusion with prominent chin?
a) Functional Appliance
b) Fixed Orthodontics
c) Functional jaw orthopedic correction
d) Surgical Orthodontics (The only option for correcting a significant skeletal discrepancy in an adult.)
48B. The presurgical orthodontic procedures involves
a) Decompensation (Removing the dental compensations (e.g., proclining lower incisors, retroclining upper incisors) to allow for proper surgical correction.)
b) Compensation
c) Settling elastics
d) Immobilization
48C. The surgical procedure of choice for correction of mandibular excessive prognathism is
a) Le Fort I osteotomy
b) Bilateral sagittal split osteotomy (The standard procedure for mandibular setback.)
c) Caldwell-luc surgery
d) Ramal distraction osteogenesis
49. Profile during chronic thumb sucking is:
a) Concave & narrow
b) Wide & concave
c) Narrow & convex (Convex due to proclined maxillary incisors; can be narrow due to maxillary constriction.)
d) Convex & wide
50. In a child, diagnosis of tongue thrusting is made by
a) Observing digits of patient
b) Lower lip is held lightly by thumb and finger and asked to swallow water (This is the “Moyers” method; if the habit exists, the tongue will thrust forward when the lip is held.)
c) Holding paper in between lips
d) Paper wick test (holding a piece of paper in front of nose)
51. The suckling reflex and infantile swallow normally disappear by the
a) First year
b) Second year
c) Sixth year
d) Eight year
52. Clinical feature of mouth breathing is
a) Pigeon face appearance (A term sometimes used to describe the long, narrow face with incompetent lips.)
b) Proctined mandibular anteriors
c) Shallow and Flat maxillary arch
d) Retrocined maxillary anteriors
53. Mature swallow pattern is characterized by all of the following EXCEPT
a) Relaxation of lips
b) Placement of tongue behind the maxillary incisors
c) Placement of the mandible until posterior teeth are in contact
d) Relaxation of the elevator muscles of mandible (In a mature swallow, the elevator muscles contract to bring the teeth into light contact.)