MDS PREP
Which appliance is not suitable for skeletal Class –III malocclusion at the age of 8 years?
1) Frankel III
2) Activator III
3) Chin cap
4) Maxillary splint appliance
Orthodontics Answer: 4
SOLUTION
Maxillary splint appliance will hold the maxilla and worsen skeletal Cl –III malocclusion.
Heat hardening is done in which orthodontic wire
1) Elgiloy
2) Stainless steel
3) TMA
4) NiTi
Orthodontics Answer: 1
SOLUTION
Elgiloy (Cobalt-Chromium) alloy is supplied in a softer state and can be heat hardened.
After hardening heat treatment, the softest elgiloy becomes equivalent to regular stainless steel.
Which of the following shows 200 % of its adult growth by age 9-10 years
1) Lymphoid
2) General
3) Genital
4) Neural
Orthodontics
Answer: 1
The lymphoid system, which includes lymph nodes, spleen, and other lymphatic tissues, undergoes significant growth during childhood. By the age of 9-10 years, the lymphoid tissue can reach approximately 200% of its adult size due to the increased demand for immune function during this period. This growth is part of the body's preparation for increased exposure to pathogens as children interact more with their environment.
Bone tissue grows by
1) Apposition
2) Interstitial growth
3) Osteoclastic growth
4) Mesenchymal tissue growth
Orthodontics Answer: 1
SOLUTION
Interstitial growth, simply means that it occurs at all points within the tissue. When mineralization takes place so that hard tissue is formed, interstitial growth becomes impossible.
"Thumb sucking" will
1) Always produce maxillary prognathism
2) Always indicate psychological disturbance
3) Always needs appliance therapy 10 break the habit
4) None of the above. Many times it stops spontaneously
Orthodontics
Answer: 4
Explanation: Thumb sucking is a common behavior in children and does not always lead to maxillary prognathism, psychological disturbances, or the need for appliance therapy. Many children stop thumb sucking on their own without intervention.
The most common permanent tooth found to be ankylosed is
1) 1st molars
2) 2nd molars
3) Canines
4) Premolars
Orthodontics Answer: 4
ankylosed teeth are also known as submerged teeth.
submerged teeth are decidous teeth most commonly mandibular second molars
Most common permanant tooth found to be ankylosed is premolars.
Which of the following cannot be used for incisor retraction
1) Roberts retractor
2) Split labial-bow
3) High labial-bow
4) Apron spring
Orthodontics
Answer: 3
The high labial-bow is typically used for molar retraction and is not designed for incisor retraction. In contrast, Roberts retractors, split labial-bows, and apron springs are all instruments that can be used effectively for retracting incisors during orthodontic treatment.
Supervision of child"s dentition is critical at or in
1) 3-6 years primary dentition
2) 7-10 years mixed dentition
3) 11-14 years permanent dentition
4) 14-17 years post permanent
Orthodontics
Answer: 2
Supervision of a child's dentition is critical during all developmental stages, but the 7-10 years age range, which is the mixed dentition stage, is a particularly important time for monitoring. This is because it is the period when both primary (baby) and permanent (adult) teeth are present in the mouth. During this stage, children are at risk for various dental problems such as crowding, malocclusion, and the loss of primary teeth that can affect the eruption of permanent teeth.