Upper removable appliance or jones jig for distalizing first molars? A randomized clinical trial

Aim: To compare the effectiveness of two intra-oral methods of distalizing upper first permanent molars: an upper removable appliance (URA) and a Jones Jig. Sample: Twelve patients were randomly allocated to URA treatment and 11 patients to a Jones Jig. Methods: Upper study models were collected at the start of treatment and after 6 months of appliance wear. The amount of distal movement, tipping and rotation of the upper first permanent molars and mesial movement of the upper first permanent premolars was measured using a reflex metrograph. Results: There were no statistically significant differences between the two treatment methods for any of the outcome measures (P <0.05). Distal movement obtained by both appliances was approximately 1 mm. Conclusions: The amount of distal movement obtained with both appliances was small and no differences were shown in the amount of molar tooth movement. It is suggested that there is no advantage in using the Jones Jig as a non-compliance appliance. © Blackwell Munksgaard 2002.