Anterior crossbite - is fixed appliance most cost effective?

The prevalence of anterior crossbites is reported to vary between 2.2 – 12%. Practitioners used both fixed and removable appliances to treat the problem with both producing successful results. While both produce good clinical outcomes, which approach is more cost effective is unknown. The aim of this study was to evaluate and compare the costs of fixed or removable therapy to correct anterior crossbite with functional shift and to relate the costs to the effects.

Methods

Patients in early to late mixed dentition with anterior crossbite affecting one or more incisors were randomised to either fixed (FA) or removable appliance (RA) treatment. Orthodontic outcome measures were success rates for crossbite correction, overjet, overbite, and arch length after active treatment and at 2 years post retention. Direct and indirect costs were calculated. ‘Direct costs’ comprised material costs and treatment time needed for manpower of all sessions and for each patient. ‘Indirect costs’ were defined as loss of income (wages plus social security costs), assuming that the patients’ parents were absent from work to accompany the patient to the orthodontic appointment. Costs were calculated in Swedish currency (SEK) based on 2013 prices and expressed in Euros (€) based on a mean currency value SEK 100 = €11.56. A cost-minimisation analysis was conducted.

Results

62 children were randomised, 31 to each treatment.
Mean treatment time, including retention of 3 months was 5.5 months (SD 1.4) for the FA group and 6.9 months (SD 2.8) for the RA group.
2 patients in each group required retreatment and this was undertaken with fixed appliances.

	Fixed appliance	Removable appliance
Mean no of appointments-all treatments and retreatment	7.8	10.1
Societal costs – successful treatment (SD)	€630 (SD 198)	€945 (SD 302)
Societal costs – all treatments and retreatment (SD)	€678 (SD 361)	€1031 (SD 511)
Direct costs – materials successful treatment (SD)	€32 (SD 3)	€227 (SD 79)
Direct costs—materials – all treatments and retreatment (SD)	€35 (SD 15)	€231 (SD 82)
Direct costs—treatment time successful treatment (SD)	179 minutes/€323 (102 SD)	205 minutes/€371 (SD 135)
Direct costs—treatment time all treatments and retreatment (SD)	194 minutes/€351 (SD 197)	231 minutes/€417 (SD 262)

The indirect costs comprised 44% of the societal costs for FA therapy and 37% for RA therapy.

Conclusions

The authors concluded:

The results confirm that for correction of anterior crossbite with functional shift, FAs offer significant economic benefits over RAs, including lower direct costs for materials and lower indirect costs. Even when only successful outcomes were considered, treatment with a RA was more expensive.

Comments

Economic analyses in dentistry are not conducted very often and even then they are not based on randomised controlled trials so it is good to see this type of study being conducted.

The study found that the overall costs included for those treatments which required retreatment were €678 for fixed appliances and €1031 for removable appliances. Of these overall (societal) costs 44% of the costs for fixed appliance were indirect costs falling on the parents and 37% for removable appliance treatment.

While this is helpful, the authors caution as to whether the findings will be more widely generalisable as many of the costs will be influenced by local factors. This paper is one of a number of publications for this small but well conducted study. We covered the treatment outcomes in an earlier blog (Dental Elf – 20^th Aug 2014) but a good summary of the publications is available in Kevin O’Brien’s latest blog.