Intermaxillary fixation (IMF) screws, typically self-tapping, are easy and quick to use, seemingly safe, are compatible with plating systems, reduce buccal and gingival tissue trauma and are used to assist with open reduction and internal fixation (ORIF) of fractured mandibles. However, there is limited literature on complications that may arise with their use.
Hashemi and Parhiz studied 373 screws in 73 patients and found that 6.5% of screws damaged dental roots, of which 13 teeth required further treatment or extraction. Coburn et al. described complications in their 122 patient study including fracture of screws upon insertion and iatrogenic damage to teeth.
Of the complications noted, firstly, we further report the risk of root damage as shown in the panoramic radiograph (OPT) following ORIF ( Fig. 1 ). We have also experienced failure at the IMF screw head-thread junction as in Fig. 2 , a complication also reported by Holmes and Coburn . Farr postulated that screw fracture at this junction might be created by the screw being placed partly into root dentine which would then require more force to insert the screw due to greater resistance, whilst this is a view that we share, we also propose that there can be, on occasion, mechanical weaknesses or faults at this junction. This unplanned separation may result in delays due to difficult intraoperative retrieval (if possible without further damage). The complications described have become more pertinent in the present climate, with greater reliance on IMF.