MDS PREP
The part of the removable appliance which provides the anchorage is
1) Adams clasp
2) Base plate
3) Active labial bow
4) Guided springs
Orthodontics Answer: 2
SOLUTION
Baseplate: The hard plastic part of some retainers that covers the gum and has the wire components of the retainers attached to it.
The diameter of labial-bow of the maxillary plate
1) 0.5-0.6 mm
2) 0.6-0.8 mm
3) 0.7-0.8 mm
4) 0.8-1.0 mm
Orthodontics
Answer: 3
The labial bow is a component of the maxillary denture framework that helps in stabilizing the denture and providing support. The diameter of the labial bow is typically measured to ensure proper fit and function. The standard range for the diameter of the labial bow is generally accepted to be between 0.7 mm and 0.8 mm
If a coil and tag of a palatal canine retractor are placed too far distally
1) Base plate is weakend
2) Tooth movement will be slowed
3) Tooth will tend to be moved buccally
4) Tooth will tend to be moved palatally
Orthodontics
Answer: 3
If the coil and tag of a palatal canine retractor are placed too far distally,
the force applied will tend to move the tooth buccally
(toward the cheek) rather than palatally (toward the
palate), which can hinder the intended movement.
In classifying molar relation in patient with premature loss of primary molar, additional relation to be noted is
1) Incisor relation
2) Canine relation
3) Midline relation
4) Premolar relation
Orthodontics Answer: 2
SOLUTION
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.
Relapse of orthodontic tooth rotation is due to periodontal traction. This is mainly caused by action of which periodontal fibers
1) Supracrestal fibres and oblique fibres
2) Supracrestal fibres and horizontal fibres
3) Supracrestal fibres and transeptal fibres
4) Transeptal fibres and oblique fibres
Orthodontics Answer: 3
PDL traction is mainly due to supracrestal fibres, transeptal fibres of gingival fibers.
It needs at least 232 days for readaptation, e.g. rotations.
To avoid relapse either circumferential supracrestal fibrotomy is done OR a prolonged retention is given.
If the tooth has not erupted to the line of occlusion it is called
1) Supraversion
2) Torsiversion
3) Rotated
4) Infraversion
Orthodontics Answer: 4
Terms used to describe the position of teeth.
Mesioversion - A tooth in the arch located more mesial than normal
Distoversion - A tooth in the arch located more distal than normal
Labioversion - An incisor or canine outside of arch towards the lips
Buccoversion - A posterior tooth outside the arch toward the cheek
Linguoversion - A tooth inside the arch form toward the tongue
Infraversion - A tooth that has not erupted to the occlusal plane
Supraversion - A tooth the has over-erupted
Torsiversion - A tooth rotated on its axis
Transversion (Transposition) - Teeth that are in the wrong sequential order.
Crowding that occurs after age of 18 is the result of
1) Impacted third molar
2) Physiological maturational change
3) Orthodontic relapse
4) Periodontal disease
Orthodontics
Answer: 2
Crowding that occurs after age 18 is typically the result of physiological maturational changes.
Explanation: Dental crowding is a common malocclusion where teeth do not have enough space to align properly in the dental arch. After the age of 18, most of the facial growth has concluded, and the teeth are fully erupted. If crowding occurs at this stage, it is most likely due to physiological maturational changes, such as the natural movement of teeth or the eruption of third molars (wisdom teeth). Impacted third molars are another potential cause of late crowding, but the question specifies that the crowding is not due to them. Orthodontic relapse is a possibility if the individual had prior orthodontic treatment, but without that context, the most likely cause for new crowding in adulthood is the natural shifting of teeth over time or the late eruption of wisdom teeth. Periodontal disease can affect tooth positioning, but it does not directly cause crowding.