Join me as I summarise Kevin O’Brien’s lecture looking at class 2 treatment, and answering the question of early Vs late treatment and fixed Vs removable appliances.

Kevin answered 3 main questions looking at systematic reviews:

1. Early Vs late treatment

2. Fixed Vs removable treatment

3. Patient relevant outcomes of Class 2 treatment

1. Early treatment (8-10 years) Vs late treatment (2-phase Vs 1-phase)

Cochrane Review: Orthodontic treatment for Class 2 Batista 2018

o No difference OJ ANB, PAR, Self concept Small order overjet 0.21mm

o No benefit to early treatment for most, and KOB suggests treatment at conventional timing in adolescence is appropriate

o Statistical difference in Trauma:

§ Experience of trauma:

· Adolescence 31.7%, Early 19.7% = 12% difference

o Relative risk reduction: 33%. Define terms, 12% is absolute risk, looks at total sample, those who have trauma and not. Relative risk is looking at the trauma sample, and what is the reduction through the intervention in the chance of it.

§ Through the intervention, 1/3 of those who would have has trauma as an adolescent, wont with early intervention

o Numbers needed to treat 1:10,

Information of benefit of early treatment

o Reduction in trauma is clinically significant

o Overall treatment time, nearly 2 x longer

o Greater cost

o Poorer occlusal outcomes

§ Patients ‘burn out’

· Moderate uncertainty in early Vs adolescent treatment

o Repeat study as lots has changed

2. Fixed Vs removable in late treatment (1-phase)

Cochrane review 2018 Batista

· Skeletal changes ANB:

o Removable: 2.37o = Statistically significant

o Fixed: 0.53 o = Statistically significant

§ Removable greater difference = 1.84, clinician to decide if clinically

· Overjet:

o Removable: 4.6 = Statistically significant

o Fixed: 5.4  = Statistically significant

§ No real difference

· Uncertainty was high in this review repeat studies

3. Patient outcomes

· Trials focus on treatment outcomes, but RCTs in orthodontics describe QOL in only 10% of trials, smaller number of functional improvement

· Might be missing effects of treatment

o Example of missed effects: KOB Twinblock Vs Herbst 2003

o Compliance:

· Herbst 2 x greater chance complete treatment

· Patient perception: TB worse

o Non-compliance of twinblock

§ Problems eating (speech, sleep)

§ Influenced school work

§ Bullying (embarrassed)

References

Batista, K.B., Thiruvenkatachari, B., Harrison, J.E. and D O'Brien, K., 2018. Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents. Cochrane Database of Systematic Reviews, (3).

Thiruvenkatachari, Badri, Jayne Harrison, Helen Worthington, and Kevin O'Brien. "Early orthodontic treatment for Class II malocclusion reduces the chance of incisal trauma: Results of a Cochrane systematic review." American Journal of Orthodontics and Dentofacial Orthopedics 148, no. 1 (2015): 47-59.

Tsichlaki, A. and O'Brien, K., 2014. Do orthodontic research outcomes reflect patient values? A systematic review of randomized controlled trials involving children. American Journal of Orthodontics and Dentofacial Orthopedics, 146(3), pp.279-285.