15 - Growth and Timing of Treatment Flashcards
How functional appliances work:
Is there a benefit in treating class II malocclusions early i.e. in the mixed dentition (two stage / phase treatment) rather than in one stage?
- Males grow for longer than females
- In males there is no growth spurt in the maxilla
- In the mandible, there is a gradual growth for both males and females.
Growth prediction:
Can be split into 3 categories:
- Timing
- Amount
- Direction
Click answer
Growth direction of the mandible
2/3 will grow forwards and upwards - reducing overjet
1/3 will grow downwards and forwards
Growth prediction
2 phase treatment
A substantial gap between 2 distinctive treatment periods
Early treatment of class _____ malocclusion works and is important
Class 2 malocclusion
(Twin block appliance - Treatment during or slightly after pubertal growth spurt resulted in greater skeletal change)
Herbst vs Twin block
Patient cooperation with the Herbst appliance is better than that with the twin block.
- Phase I treatment is more rapid with the Herbst appliance, but overall duration of treatment
is similar to that with the twin block. - The Herbst appliance is prone to debonding and component breakage – Lengthy reviews to
rebond. - There is no differences in the dental and skeletal effects of treatment between the 2
appliances.
- patient has higher self concept scores with twin block
Full time or part time wear better
Full time wear of functional appliances leads to quick improvement of overbite and overjet
Identify these 2 functional appliances
Top = Herbst appliance ]
Bottom = twin block
Is it better to have transition phase between twin block and fixed appliance e
Better to have No transition phase between twin block and fixed appliance
Why treat patients with large overjet
RISK OF TRAUMA to upper incisors
Increased prevalence of trauma to upper incisors with overjets greater than 5mm
Why treat patients with large overjet especially early treatment?
RISK OF TRAUMA to upper incisors
(Increased prevalence of trauma to upper incisors with overjets greater than 5mm)
Soft tissue maturation
LAFH - lower anterior face height - increased with functional appliances
Controversies of class 2 treatment :
Effects of functional appliances - for class II treatment
Increased overjet and lip trap
Deep traumatic overbite
Class II
Before and after treatment - cephalometric view
Red line = head gear effect - rolling and tipping back of whole maxillary dentition
Notice inclination of upper first molar and upper incisors -
CLICK FOR ANSWERRS
Little evidence
2- maybe because of psychological benefits but not in terms of efficiency of treatment
3- yes - herbst and twin block most effective out of the rest
Class III - not sure about what this FC is about but click for answer
Sometimes taken out on early mixed dentition - as can be done quickly and better stability than class 2 treatment
Mixed dentition:
1. Movement of teeth
2. Treatment of underlying skeletal discrepancy
Incisors over bite:
1. Mild skeletal problem
2. Upper incisors not proclined
3. Positive overbite
Class III treatment of skeletal discrepancy EARLY treatment
Treatment of skeletal discrepancy (a second approach may be necessary after completion of growth )
- Early mixed dentition
- Late mixed dentition
Could use face mask usu combined with rapid maxillary expansion as shown below
Or removable functional appliance such as reverse twin block
