Comparison of objective wear time between monoblock and twin-block appliances measured by microsensor

To assess the objective compliance levels in skeletal Class II patients with mandibular retrognathia wearing monoblock and twin-block appliances.

A prospective clinical study was conducted with 30 patients between 10 and 15 years old who were equally divided into two study groups. Group 1 was treated with monoblock, and group 2 was treated with twin-block appliances. The patients were instructed to wear their appliance for 15 hours per day. Wear times were monitored by a microsensor. (TheraMon; MCTechnology, Hargelsberg, Austria) for an average of six appointments. Patients were also instructed to record their wear times on a chart, and this record was admitted as subjective wear time. Statistical analysis was performed with the data derived from both the patients' charts and the monitoring records.

The mean wear time by the patients was 10.67 ± 3.93 hours, which was less than the 15 hours prescribed by the orthodontist, with no difference between the two appliances (P > .05). The regular use rate, which included the days with a wear time of 8 hours or more per day, was 75%. Compliance levels decreased by 35% throughout the six control appointments. Patients declared that their wear time was more than their objective wear time by an average of 3.76 hours.

Despite their different designs, there was no significant difference between the monoblock and twin-block appliances in terms of compliance.