Treatment of atrophic mandibular fractures based on the degree of atrophy--experience with different plating systems: a retrospective study.
ABSTRACT The aim of this retrospective study was to evaluate the clinical outcome of fractures of the atrophic mandible based on the degree of atrophy and treatment by different plating systems.
Thirty patients with 40 fractures of atrophic mandibles were treated by open reduction and internal fixation at our department between 1994 and 2001. Twelve fractures occurred in Class I (between 15- and 20-mm bone height), 10 fractures in Class II (between 10 and 15 mm), and 18 fractures in Class III atrophy (<10 mm). The profile heights of plating systems used for stabilization varied from 0.5 to 2.2 mm and were applied with an intraoral (n = 37) and extraoral (n = 3) approach.
In 36 fractures, bone healing was uneventful. Major complications (loose hardware or nonunion) occurred in 4 fractures: 2 in Class II and 2 in Class III atrophy. Major complications were observed with 1.4-mm (n = 3) and 2.2-mm (n = 1) plates. Minor complications (infections or dehiscence) were observed in 6 fractures: 3 in Class II and 3 in Class III atrophy. Hypesthesia of the inferior alveolar nerve was present 1 week and 1 year postoperatively in 39 and 16 fractures, respectively.
Treatment of atrophic mandible fractures should be based on the degree of atrophy. More rigid fixation may be necessary in mandibles with less than 15 mm bone height.
- SourceAvailable from: Valfrido Antonio Pereira-Filho[Show abstract] [Hide abstract]
ABSTRACT: Atrophic mandible fractures are frequently a challenge to stabilize. This study evaluated, through mechanical testing in vitro, the number of locking screws that is sufficient to withstand loading when applied with a locking reconstruction plate in the fixation of atrophic mandible fractures. Polyurethane mandibles with a simulated linear fracture at the midline were used as substratum. Results show that resistance of the fixation is poor when one and two screws are used on each side of the fracture. Three screws on each side of the fracture significantly increases the resistance to displacement. However, no additional strength is added to the construct when more than three screws per side are used.International Journal of Oral and Maxillofacial Surgery 03/2013; · 1.52 Impact Factor
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ABSTRACT: The objective of the present study was to conduct a computational, laboratory-based comparison of the biomechanical stability of 2.0 fixation locking plates with different profiles in Class III atrophic mandibular fractures using 3-dimensional finite element analysis. Three-dimensional finite element models simulating Class III atrophic mandibular fractures were constructed. The models were divided into 4 groups according to plate thickness (1.0, 1.5, 2.0, and 2.5 mm). Fractures were simulated in left mandibular bodies, and 3 locking screws were used on each side of each fracture for fixation. Bite forces of approximately 63 N were simulated in the incisor and molar regions of the mandibles in finite element models. The level of compressive strain on the bone around the screw was within the physiological limit. No significant difference was observed in the displacement of bone segments in the fracture region. Von Mises stress was higher during simulated bites in the molar region for plates with thicknesses of 1.0 mm. Plate tension values were below the level required for permanent deformation or fracture in all models. The 2.5-mm-thick plate presented better biomechanical performance than all other plates. The 2.0-mm-thick plate also showed satisfactory results and adequate safety limits. Large-profile (2.0-mm-thick) locking plates showed better biomechanical performance than did 1.0- and 1.5-mm-thick plates and can be considered an alternative reconstruction plate for the treatment of Class III atrophic mandibular fractures.Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 02/2013; 71(2):335-42. · 1.58 Impact Factor
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ABSTRACT: Fractures of the severely atrophic (<10 mm) edentulous mandible are not common, and these fractures with a vertical height of 10 mm or less have long been recognized as being particularly problematic. Although there are advances in the treatment of the atrophic mandibular fracture, the treatment remains controversial. There are some options for treatment planning because of using small miniplates to large reconstruction plates. However, when the fixation method fails, it causes malunion, nonunion, and/or infection, and sometimes it has been associated with large bone defects. The authors describe a clinical report of a failed miniplate fixation for atrophic mandibular fracture management. The authors used a load-bearing reconstruction plate combined with autogenous bone graft from iliac crest for this retreatment. The authors show a follow-up of 6 months, with union of the fracture line and no complication postoperatively.The Journal of craniofacial surgery 07/2013; 24(4):e415-e418. · 0.81 Impact Factor