Page 33 - Open versus closed Mandibular condyle fractures

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Chapter 2.1 Closed
The closed treatments described in the studies analyzed consisted mainly of a period of MMF, and the choice to use MMF was generally based on the presence of malocclusion. Other reasons for using MMF were swelling, deviation on mouth opening, simultaneous mandibular fractures, pain, and restriction of mandibular movements.
The duration of immobilization reported in prior studies is variable, ranging from 2 weeks to 6 weeks.5, 42 It has also been suggested that no immobilization is required, and that active physiotherapy with strict follow-up is sufficient.43 Others recommend early mobilization of the jaw in all cases, and suggest that functional rehabilitation is an essential part of the treatment.5 Longer periods of immobilization are reportedly associated with an increased risk of ankylosis.44, 45 With regard to the mechanism of action of closed treatment, various explanations exist. According to Ellis and Throckmorton,43 adaptations on three levels are necessary to maintain normal occlusion: the neuromuscular level, the skeletal level, and the dentoalveolar level. Neuromuscular adaptation consists of masticatory adaptations. Skeletal adaptation comprises condylar regeneration and remodeling of the joint.46 The ability of the condyle to remodel and regenerate is impaired and less predictable following dislocation of the condyle,47 and is age-dependent.34 When skeletal growth has ceased, the condylar cartilage is mature and remodeling will generally be absent. In these cases, only functional remodeling will occur.48 Lastly, fine tuning of the occlusion will occur via extrusion of the anterior teeth and/or intrusion of the posterior teeth.49
Where the fixation method for MMF was reported, arch bars were used in the majority of studies. Other choices were Ernst ligatures and head chin caps, or the use of a splint or a bite block. Recently, van den Bergh et al.50 reported that the use of MMF screws as a closed treatment for condylar fractures led to a higher quality of life during the 6-week period of fracture healing than when arch bars were used. Krause and Bremerich,30 Marker et al.,21 and Rutges et al.28 used stainless steel wires for MMF, whereas Niezen et al.23 used guiding elastics. The strain of elastics used was not described in most studies, with the exceptions of the reports by Dijkstra et al.20 and Niezen et al..23 In the other reports included in the final analysis, the MMF method was not described.