Orthodontic Biomechanics

Which type of orthodontic force is the most physiologic for tooth movement?

• Interrupted

• Intermittent

• Continuous

• Light and continuous

Couple of a force is

• Two equal perpendicular forces

• Two equal forces acting in same direction

• Two non-equal perpendicular forces acting in opposite direction

• Two equal parallel forces acting in opposite direction

Frontal resorption is caused by

• Light intermittent force

• Light interrupted force

• Light continuous force

• Heavy intermittent force

Mild force during orthodontic tooth movement produces

• Acute pulpitis

• No effect on pulp

• Mild hyperaemia

• Necrosis of pulp

The life span of an osteoclast is estimated to be

• 2-4 days

• 5-10 days

• 10-15 days

• 15-20 days

Closing of midline diastema by using a removable appliance

• Reciprocal single simple anchorage

• Reciprocal simple compound anchorage

• Reciprocal stationary simple anchorage

• Reciprocal stationary compound anchorage

Application of intermaxillary elastics from upper molar to the lower anteriors is called

• Class I traction

• Class II traction

• Class III traction

• Class IV traction

In periodontally compromised tooth, which of the following movements is done very carefully

• Tipping

• Uprighting

• Intrusion

• Proclination

In adult patients, the centre of resistance lies

• At the centre of the root

• At the incisal edge of the crown

• Shifted more apically

• shifted more cervically

Centre of rotation of a body can be

• External

• Internal

• Any of the above

• Cannot be predicted