The subcondylar area is the most common site of mandibular condylar fracture1,2. The treatment of subcondylar fractures can be divided into two major treatment methods: closed treatment or closed reduction (CR) and open reduction and internal fixation (ORIF). CR requires a period of maxillomandibular fixation (MMF), followed by active physiotherapy. ORIF allows good anatomical repositioning and immediate functional movement of the jaw. This study compares the clinical and radiological outcomes after CR and ORIF management of subcondylar fractures.

Forty-eight patients presenting with subcondylar fracture between January 2010 and March 2013 at the Department of Oral and Maxillofacial Surgery, Gachon University Gil Medical Center were included in this retrospective study. The treatment methods were decided according to the surgeons' preferences and experiences. Fifteen patients (14 males and 1 female) with an age range of 6 to 52 years (mean, 42 years) were treated with CR, and 33 patients (28 males and 5 females) with an age range of 17 to 62 years (mean, 34 years) underwent an ORIF operation. Patients with CR were followed-up for an average of 10.7 months (range, 3 to 36 months). Those with ORIF were followed-up for an average of 3.8 months (range, 3 to 24 months). All patients included in this study had more than three months of follow-up. A telephone survey was performed for the 6 CR patients who did not visit the clinic for three months after the first visit.

Chart review was performed, and occlusion, maximal mouth opening, deviation on mouth opening, and nerve injury were evaluated. Radiologic assessment was also performed to evaluate the tangential angulation of the displaced fragment and loss of ramus height, as described in Palmieri et al.3. The amount of condyle fragment displacement (tangential angulation and loss of ramus height) was evaluated on panoramic radiographs at the first visit and three months later.(Figs. 1, 2)

The data were analyzed using IBM SPSS Statistics for Windows, version 19.0 (IBM Co., Armonk, NY, USA). Measurements are given as the mean±standard deviation. Comparisons between the two groups were performed using the Mann-Whitney U test.

Despite a plethora of treatment guidelines, management of subcondylar fracture of the mandible remains controversial. During the past few decades, CR has been the preferred treatment4; however, closed treatment requires a period of MMF, followed by active physiotherapy5. Also, long-term complications such as pain, arthritis, open bite, deviation of the mandible on opening, inadequate restoration of vertical height of the ramus leading to malocclusion, and ankylosis can result from the CR method6. However, we found no significant differences between groups in the average period of MMF (5.47 days in CR group and 6.33 days in ORIF group) and no serious complications.

Surgical treatment allows proper anatomical repositioning and immediate functional movement of the jaw7. There is consensus that correct anatomical repositioning of the mandibular condyle process is an important prerequisite for reestablishing function8. In cases of severe displacement or dislocation, surgical management is preferred6,9. In our study, all treatment methods were decided by the treating surgeons. In our clinics, doctors tend to provide CR for patients with less displaced fractures and ORIF to those with more displaced fractures. The preoperative tangential angulation in the CR group (3.67°±2.53°) was significantly less (P=0.002) than that in ORIF group (8.66°±5.12°). However, the difference between the groups in preoperative loss of ramus height was not significant.

Palmieri et al.3 reported that open reduction might produce functional benefits for patients with severely dislocated condylar process fractures, and Undt et al.7 reported that ORIF allows appropriate anatomical repositioning and immediate functional movement of the mandible. Similarly, in our study, the difference between preoperative and postoperative loss of ramus height in the ORIF group (2.60±2.02 mm) was statistically greater than that in the CR group (1.25±1.61 mm; P=0.008). The difference between preoperative and postoperative tangential angulation in the ORIF group (6.92°±4.86°) was statistically greater than that in the CR group (0.32°±1.56°; P=0.000).

Haug and Assael10 showed no differences for maximum interincisal opening, deviation on opening, and occlusion between closed and open management groups after treatment. Likewise, we found no clinical differences, such as occlusion or interincisal mouth opening, between the CR and ORIF groups. However, 6 patients (40%) in the CR group and 11 patients (33%) in the ORIF group showed deviation on maximal opening of the lower jaw three months after treatment. Our study used only 48 patients and a relatively short follow-up period. Future research should compare the outcomes of many more cases with long-term follow-up.

In conclusion, CR had clinically satisfactory results, although ORIF produced more accurate reduction of fractured fragments. In the absence of distinct displacement of a fractured fragment, therefore, CR should be selected over ORIF to prevent the need for an operation.