Hypodontia Flashcards
What is the incidence of missing laterals incisors?
2% population
Most common absent teeth, 1-5
1) Lower 3rd molars
2) Lower 2nd premolars
3) Upper lateral incisors
4) Upper 2nd premolars
5) Lower canines
Please give reasons why an orthodontist may plan to open space rather than close space for missing upper lateral incisors
• Colour from canine to central
• Shape of Canine
• Position of adjacent teeth / intercuspation
• Space closure may be slower
• Age of patient
• Cost implications for implants / bridges
• Attitude of family
• Function of teeth
Aesthetically pleasing to have prosthetic – the canines could be too big to disguise
as laterals and are not always the ideal colour.
Maintain good canine and molar relationships.
May not be possible to close space completely.
Some orthodontists may choose to place a lateral bracket on the canine in cases when they plan to place the upper canine in the lateral incisor position, Please discuss an advantage and a disadvantage of this decision.
Advantage
• Bracket prescription best represents the ideal lateral position – in terms of tip and torque
Disadvantage
• Base doesn’t fit the contours of the tooth and as such the prescription is not fully expressed. Also it is a small bracket for a large tooth with large root and this is another reason the prescription would not be faithfully realised.
What is the IOTN score for a patient with hypodontia and what is the difference between both of them?
• 4h - Less extensive hypodontia requiring pre-restorative orthodontics or orthodontic space closure to obviate the need for a prosthesis
• 5h - Extensive hypodontia with restorative implications (>1 tooth missing in any quadrant) requiring pre-restorative orthodontics
