To the best of our knowledge, this is the first described report of a case of postoperative dysphagia caused by a delay in mandibular fracture treatment. The findings in this case have two important implications. First, postoperative dysphagia caused by disuse atrophy may occur if treatment is delayed in severe mandibular fracture. The postoperative complications of mandibular fracture include malocclusion, infection, nonunion, osteomyelitis, and sensorial mental nerve dysfunction [
5‐
8]. Previous studies did not show any significant correlation between complications arising during treatment of mandibular fracture [
6,
8]. Patient’s comfort and well-being, as well as any psychological effects caused by disfigurement of unrepaired mandibular fractures, should be considered with a reasonable length of treatment delay [
8]. In fact, most patients received treatment within 2–4 days after injury [
6]. In the study of Patrocinio
et al. [
5], about 73% of patients were treated within the first week, and 14% were managed after 15 days or more. In this case, ORIF was performed 16 days after the accident because of difficulties in securing a psychiatric bed and treatment for aspiration pneumonia prior to ORIF. Ohba
et al. [
9] reported a case of aspiration pneumonia accompanied by impaired swallowing function owing to a double mandibular fracture. The symptoms of aspiration pneumonia improved immediately after surgery. Hence, open reduction should be performed immediately to prevent aspiration pneumonia caused by swallowing dysfunction. In this case, long-term open bite attributed to severe mandibular fracture caused sialorrhea and aspiration pneumonia via decreased swallowing function. Interestingly, Shimizu
et al. [
10] assessed the geniohyoid muscle via ultrasonography perioperatively in patients who underwent thoracotomy and laparotomy. Results showed that muscle atrophy due to surgical invasion or disuse may occur in the deglutition muscles, as in the limb muscles. Furthermore, muscle atrophy can develop in the early postoperative period and can persist even after 2 weeks from surgery. In the case of symphyseal, parasymphyseal, or condyle fracture, deviation of the mandible is mild because both side mastication muscles are balanced. On the other hand, in the case of mandibular body or angle fracture, the masseter, medial pterygoid, and temporalis muscles contribute to the superior and medial displacement of the proximal segment. Furthermore, digastric, mylohyoid, and geniohyoid muscles contribute to the inferior displacement of the distal segment. Therefore, there is higher risk of atrophic dysphagia by the local neuromuscular misbalance owing to significant gap between proximal and distal segments. In this case, normal occlusion was achieved via ORIF, and severe mandibular fracture (that is, structural disorder) was managed. Nevertheless, disuse atrophy (that is, functional disorder) occurred during the time between falling and ORIF, and dysphagia was still observed after surgery. The reserved capacity is reduced among elderly individuals and those with severe intellectual disability [
11,
12]. Thus, not only structural disorder but also functional disorder should be considered in planning the treatment for severe deviated mandibular fracture.
Second, patients with severe intellectual disability can develop postoperative dysphagia caused by disuse atrophy. Hence, adequate dysphagia rehabilitation cannot be facilitated, and percutaneous endoscopic gastrostomy may be required. Therefore, early ORIF is recommended for mandibular fracture in a patient with severe intellectual disability. In addition to videoendoscopic examination findings, on the basis of the facts that satisfactory occlusion was achieved with ORIF, the patient was on a soft diet and could feed without assistance before the accident, the dosage and type of medications were not changed, and severe anterior open bite persisted for more than 2 weeks, the patient was diagnosed with disuse atrophy of muscles for swallowing, including the tongue. Normally, the combination of compensatory techniques (that is, postural maneuvers), indirect therapy (exercises that can strengthen swallowing muscles, including oral care), and direct therapy (exercises for swallowing) was required for dysphagia rehabilitation [
13‐
15]. However, we could not adequately facilitate dysphagia rehabilitation. Thus, only oral care, thermal–tactile stimulation, and cervical range of motion training were continuously provided as indirect therapy and percutaneous endoscopic gastrostomy was required in this case. Therefore, we should keep in mind that “people with intellectual disabilities vary in characteristics, abilities, and preferences, but health professionals must not hold back from treating them” [
1]. Thus, ORIF should be immediately performed. Moreover, efforts should be taken to prevent severe complication in individuals with severe maxillofacial injuries.
This case report had limitations. That is, we cannot completely rule out the risk of drug-induced dysphagia [
15‐
17] because the patient was under treatment with several antiepileptic and antipsychotic drugs. However, the dose was not changed before and after surgery. Furthermore, we did not evaluate swallowing function preoperatively or reevaluate after a long period after surgery to decide whether this complication is related to the delayed surgery or disability of the patient [
18,
19]. Thus, further studies on cases of postoperative dysphagia in patients with mandibular fracture should be conducted to validate whether delay in mandibular fracture treatment can cause dysphagia.