| Abstract|| |
Background: Fractures of the condyle account for one third of all the mandibular fractures. Different surgical approaches to the condyle described hitherto testify to the advantages and disadvantages of the different surgical techniques used for approaching the condyle in such cases of fractures. We have described and compared two of such surgical techniques in this study.
Aim: The aim of this study is to compare the outcome of dealing with condylar fractures by two different surgical techniques: the mini retromandibular approach, and the preauricular approach.
Materials and Methods: A prospective study of 31 patients who had suffered with mandibular condylar fractures was carried out. Of these, 26 patients had unilateral condylar fractures, and 5 patients had a bilateral fracture. Further, 19 of these patients were treated by the mini retromandibular approach and 12 by the preauricular approach. The treated patients were followed up and evaluated for a minimum period of 1 year and assessed for parameters such as the maximum mouth opening, lateral movement on the fractured side, mandibular movements such as protrusion, dental occlusion, scar formation, facial nerve weakness, salivary fistula formation and time taken for the completion of the surgical procedure.
Statistical Analysis: t- test was used for statistical analysis of the data obtained in the study.
Results: Dental occlusion was restored in all the cases, and good anatomical reduction was achieved. The mean operating time was higher 63.53 (mean) ± 18.12 minutes standard deviation (SD) in the preauricular approach compared to 45.22 (mean) ± 18.86 minutes SD in the mini retromandibular approach. Scar formation was satisfactory in almost all the cases.
Keywords: Condylar fractures, mini retromandibular approach, preauricular approach
|How to cite this article:|
Kumaran S, Thambiah L J. Analysis of two different surgical approaches for fractures of the mandibular condyle. Indian J Dent Res 2012;23:463-8
Fractures of the condyle account for one third of all the mandibular fractures. Management of displaced condylar fractures in adults remains controversial with different techniques described by different authors. The resultant morbidity from the surgical approach to the mandibular condyles and the time consumed in these techniques inhibit the surgeons from using these methods freely. Approaches described hitherto testify to the advantages and disadvantages of the individual techniques. The critical factors in deciding the approach for surgical management include: the patient's age; site of the mandibular fracture and the degree of the mandibular displacement.
|How to cite this URL:|
Kumaran S, Thambiah L J. Analysis of two different surgical approaches for fractures of the mandibular condyle. Indian J Dent Res [serial online] 2012 [cited 2019 Oct 14];23:463-8. Available from: http://www.ijdr.in/text.asp?2012/23/4/463/104950
There is a consensus amongst oral and maxillofacial surgeons that intra articular fractures are better managed conservatively with short term intermaxillary fixation (IMF) and intense rehabilitation. Conversely, there is little agreement on the management of extra-articular fractures in adults, protocols depending on the surgeon's experience and beliefs. Recent accounts in publications hold that surgically treated condylar fractures yield better results in terms of occlusion, masticatory function, mouth opening and bone morphology. However, the preference for conservative management is still prevalent, as surgical management is technically demanding and involves risks such as facial nerve injury and unsightly scars.  Surgical routes to access the condyle are many and each has its own advantages and disadvantages. The risk of facial nerve damage and unsightly scars is reduced in the intra oral approach; however, this method is technically difficult to expedite, and requires special training and dedicated instruments. Further, external access does allows straightforward fracture reduction; however, the risk of facial nerve injury and visible scars cannot be ignored. 
It is important for oral and maxillofacial surgeons to reach a consensus about the best way of managing mandibular condylar fractures, as this will help in their early decision making, as well as allow them to better enlighten their patients about the protocol being followed and the alternate approaches, thus giving the pateints' the power to choose with informed consent.  Approaches for the efficient reduction and fixation of condylar fractures include: the submandibular approach; the preauricular approach; and, the retromandibular approach. In addition, there is a technique for the removal and replantation of the condylar segment through ramus osteotomy. 
Various ways of treating fractures of the condyle are the submandibular, preauricular, intraoral and retromandibular approaches. Closed reduction does away with surgery; but however, carries its own disadvantages such as prolonged period of jaw immobility, limited mobility combined with dietary restrictions, decreased ability to maintain good oral hygiene (especially lingually) and transient periodontal damage. These drawbacks do not make it the treatment of choice in this era of semi rigid and rigid osteosynthesis. We now require methods that allow faster rehabilitation of the patient while maintaining a better quality of life with minimal or no complications. , The surgical approaches which help achieve these benefits and hence are favoured, include the preauricular and the retromandibular approaches. These two approaches are also being followed at our centre.
| Materials and Methods|| |
31 patients with 36 fractured condyles were included in the study group and treated by the preauricular and mini retromandibular appraches. 26 of these patients had unilateral condylar fractures and 5 had bilateral condylar fractures. The time frame of the study extended from June 2005 through June 2010. One of the patients with bilateral condylar fracture with the associated parasymphysis fracture was operated only one side for medical reasons. Routine hematological evaluation was done for all patients and all were within normal parameters in all. Radiographic investigations included orthopantomograms and posterior anterior (PA) view of the mandible. Patients with a condylar fracture but no displacement, dislocation, or derangement of occlusion were treated by closed reduction via elastics or wire IMF. Informed consent was taken from every patient after explaining the merits and demerits and comparison of open and closed reduction methods of treating the condyle fracture.
The patients with the following criteria were included for open reduction: 
All the patients were treated under general anesthesia with nasoendotracheal intubation. Post-operative recovery was uneventful in all the patients.
- Unilateral condylar fractures with occlusal derangement where it was impossible to achieve pre traumatic or adequate occlusion by closed reduction;
- bilateral condylar fractures with resultant anterior open bite, where there was no option of closed reduction; two patients had history of mental retardation/psychiatric problems;
- associated fractures: unilateral, bilateral and others;
- where patient not willing for IMF;
- contra indication for IMF
The mini retromandibular approach
The mini retromandibular approach was used in 19 of 31 patients. The surgical technique adopted after the naso endotracheal intubation involved: making a 1 cm long skin incision parallel to the posterior border of the mandible and commencing 0.5 cm below the earlobe [Figure 1]. This incision was made with a No.15 BP blade and in the skin only. The deep dissection that followed was carried out using monopolar and bipolar diathermy, with blunt dissection of the parotid gland with a small curved hemostat. All the layers were clearly identified and undermined on either side of the incision to facilitate a tension free and easy closure. The parotid capsule was incised and the gland was dissected anteromedially towards the posterior border of the mandible. The fracture site on the posterior border of the mandible was identified and the pterygomasseteric sling was incised by diathermy. The fractures were reduced and fixation was carried out with miniplate osteosynthesis using a 1.5 mm osteosynthesis system. The condylar fragment was plated first with the mouth wide open, followed by plating of the distal fragment while manually maintaining the optimum occlusion. In some of the cases, a wire placed through the last hole on the plate helped to draw the fragment of the condyle into place [Figure 2]. Water-tight closure of the parotid capsule was ensured. Layered closure with resorbable sutures and skin closure with non resorbable sutures was carried out. Suturing was done subcutaneously using a 4-0 nylon or 4-0 monofilament sutures.  [Figure 3]
The preauricular approach
The incision for the preauricular approach outlined through the junction of the facial skin, the natural skin fold along the entire length of the ear and the helix of the ear. [Figure 4] The incision was made through the skin and subcutaneous connective tissues (including temporoparietal fascia) to the depth of the temporalis fascia (superficial layer), and extended superiorly to the crest of the helix, and in a few cases also involved an anterior (hockey-stick) extension. This developed a flap which was then dissected anteriorly at the level of the superficial (outer) layer of temporalis fascia. The dissection proceeded bluntly adjacent to the external auditory cartilage below the zygomatic arch. At the root of the zygoma, the incision was made through both the superficial layer of the temporalis fascia and the periosteum of the zygomatic arch. Inferior to the zygomatic arch, blunt scissors were used for dissection. Once the dissection was about 1 cm below the arch, the intervening tissue was released posteriorly along the plane of the initial incision. The entire flap was then retracted anteriorly, and blunt dissection at this depth exposed the articular eminence. The Temporomandibular joint (TMJ) was exposed with retraction of the developed flap. The fracture was reduced and fixed with miniplate osteosynthesis using a 1.5 mm osteosynthesis system. [Figure 5] Subcutaneous tissues were closed with resorbable sutures. The skin was then closed in layers with non resorbable sutures  [Figure 6].
Dental occlusion was deranged and open reduction with internal fixation was done in all cases.
The cases of all the patients operated on were reviewed 3 days a week for 2 weeks, every week for 3 weeks and after it, every month for a period of over a year. The following parameters were assessed during each follow up:
- Maximum mouth opening;
- lateral movement on the side fractured and the side opposite to it;
- protrusive movement;
- mandibular movements;
- pain (Visual Analogue Scale);
- scar formation;
- and, facial nerve weakness and salivary fistula.
t-Test was performed for the statistical analysis and the results are given in Annexure - 1 and analyzed below.
| Results|| |
The results for each patient have been tabulated and presented in Annexure 1. Among the 31 patients, 19 were treated by the mini retromandibular approach. Maximum mouth opening at the end of 3 months was 42.63 (mean) ± 8.63 cm standard deviation (SD) in patients where mini retromandibular approach was used and 47.04 (mean) ± 7.00 cm in patients where the preauricular approach was used [Table 1]. Protrusive movement at the end of 3 months was 4.92 (mean) ± 1.88 cm SD in cases of the mini retromandibular approach, and it was 4.84 (mean) ± 1.13 cm SD in cases of the preauricular approach [Table 2]. On the fractured side, there was lateral movement of 4.12 (mean) ± 2.08 cm SD in cases of the mini retromandibular approach, and it was 3.87 (mean) ± 1.33 cm SD in cases of the preauricular approach [Table 3]. On the normal side there was lateral movement of 6.27 (mean) ± 2.76 cm SD in cases of the mini retromandibular approach, and it was 6.39 (mean) ± 2.13 cm SD in cases of the preauricular approach [Table 4].
In all the cases, good anatomical reduction was achieved and there was no problem with the dental occlusion. The presence of good mandibular movements was seen in both the groups. No statistically significant association was noticed in the mandibular movement between the groups (P > 0.05). Movement of the mandible was restricted in 2 cases of each group. There was a statistically significant difference in pain felt before and after the reduction of the fractures of the condyle. The pain was evaluated the by use of a Visual Analogue Scale (VAS) which was a horizontal line, 100 mm in length, anchored by word descriptors at each end with markings from 0 through 10 and the patient was asked to describe the pain with relation to this Visual Analogue Scale with 0 being No Pain and 10 being extremely severe pain. Before treatment [Table 5], pain value was 7.18 (mean) ± 1.91 SD in cases of mini retromandibular approach, and was 8.86 (mean) ± 1.10 SD in cases of preauricular approach. After treatment [Table 6], the pain felt was of 1.76 (mean) ± 1.17 SD in cases of mini retromandibular approach and it was 3.18 (mean) ± 1.21 SD in cases of preauricular approach.
Almost all the patients of the mini retromandibular group were happy as the scar was not visible after a year, and those in the preauricular group were bothered because of the unsightly scar formation. The mean operating time of the preauricular group was higher, 63.53 (mean) ± 18.12 minutes compared to 45.22 (mean) ± 18.86 minutes of the mini retromandibular group [Table 7]. Facial nerve weakness was present in 1 out of the 19 cases of mini retromandibular approach [Table 8]. Facial nerve weakness was present in 3 out of 12 cases where the preauricular approach was used. The difference in mean operating time between the two groups is statistically significant (P < 0.01). Scar formation was seen in all the cases [Table 9] Bilateral closed sialocele was present only in one patient, where the fracture was reduced using the mini retromandibular approach. In both groups significant reduction in pain was seen after the surgical treatment of the fracture.[Table 10] and [Table 11] In all the other cases, dental occlusion was restored and good anatomical reduction was achieved. No significant difference was found in the mandibular movements after surgery in the two groups [Table 12].
|Table 10: Comparison of pain in Preauricular group before and after treatment|
Click here to view
|Table 11: Comparison of pain in retromandibular group before and after treatment|
Click here to view
| Discussion|| |
The choice of the surgical approach to the condyle in cases of mandibular condylar fractures depends upon the individual maxillofacial surgeon and is based on their experience with the technique and their personal beliefs. Some favor open reduction and rigid fixation of condylar fractures, while others do not. Although the preauricular approach is indicated in higher neck fractures, it allows a less than satisfactory view, especially when dealing with lower fractures. The surgeon has to work perpendicular to the fracture, which makes the procedure not only uncomfortable, but also limits the rigid fixation The submandibular and retromandibular approaches described in literature allow for good fracture reduction; however, require long skin incisions. There is always an associated risk of losing the facial nerve fibers, especially the marginal mandibular branch in these surgical approaches.  Submandibular approach is used very commonly for sub-condylar fractures, and conversely, the preauricular approach is used very rarely for these fractures. Extraoral approaches for the treatment of condylar fractures facilitate better exposure of the operating field, and simplify the fracture repositioning compared to the cosmetically more favorable intraoral approaches. However, they still have potential for complications such as risk for the facial nerve injury and unsightly scars. The preauricular approach is usually preferred in the treatment of high condylar neck fractures. However, the management of subcondylar fractures by preauricular approach can be problematic for treating lower fractures such as that of the subcondyle, and may also compromise the mobilization. 
The mini retromandibular approach is a conservative modification of the retromandibular approach mentioned in literature, in that, the incision proposed is only 1 cm long as opposed to the classical incision of 2.5-3 cm. The mini retromandibular approach differs from the preauricular approach in many ways. First, the skin incision is located posterior to the mandibular angle and is limited to 1 cm in length. Secondly, subcutaneous dissection allows the extension of the surgical wound to the level of the fracture. Thirdly, all subsequent phases are performed perpendicular to the fracture ends, which while allowing the surgeon to work perpendicular to the fracture, also facilitate the reduction of medially displaced proximal stumps which are generally very hard to manage in other approaches. [Figure 7] Further, the articular capsule is never breached, which is a major postoperative function advantage; Also, this view provides an optimal view of the bony field to the surgeon, making the technique very rapid and easy to learn without any special training requirements. 
| Conclusion|| |
According to the recent publications, open reduction and internal fixation of condylar fractures provides better results. The preferred surgical approach should be one that allows straightforward fracture management whilst minimizing the potential risks such as facial nerve lesions and unsightly scars. Hence, the mini retromandibular approach is preferred over the preauricular approach, as it is extremely easy and fast to perform and carries a very low risk of damaging the facial nerve whilst leaving a barely noticeable scar.
| References|| |
|1.||Wilson AW, Ethunandan M, Brennan PA. Transmasseteric antero-parotid approach for open reduction and internal fixation of condylar Fractures. Br J Oral Maxillofac Surg 2005:43:57-60. |
|2.||Newman L. A clinical evaluation of the long-term outcome of patients treated for bilateral fracture of the mandibular condyles. Br J Oral Maxillofac Surg 1998;36:176-9. |
|3.||Downie JJ, Devlin MF, Carton AT, Hislop WS. Prospective study of morbidity associated with open reduction and internal fixation of the fractured condyle by the transparotid approach. Br J Oral Maxillofac Surg 2009;47:372-3. |
|4.||Biglioli F, Colletti G. Mini-retromandibular approach to condylar fractures. J Cranio Maxillofac Surg 2008;36:378-83. |
|5.||Choi BH, Yoo JH. Open reduction of condylar neck fractures with exposure of the facial nerve. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88:292-6. |
|6.||Renato V, Ibrahim D, Abreu ME, Heitz C, de Oliveira RB, Rogério Miranda P, et al. The treatment of condylar fractures: To open or not to open? A critical review of this controversy. Int J Med Sci 2008;5:313-8. |
|7.||Dunaway DJ, Trott JA. Open reduction and internal fixation of condylar fractures via an extended bicoronal approach with a masseteric myotomy. Br J Plast Surg 1996;49:79-84. |
|8.||Chossegros C, Cheynet F, Blanc JL, Bourezak Z. Short Retromandibular approach of aubcondylar fractures. Oral Surg Oral Med Oral Pathol 1996;82:248-52. |
|9.||Villagra Siles EJ, Rodríguez Perales MA, Pou López VC. Retromandibular approach for subcondylar fractures. Acta Otorrinolaringol Esp 2006;57:186-8. |
|10.||Narayanan V, Kannan R, Sreekumar K. Retromandibular approach for reduction and fixation of mandibular condylar fractures: A clinical experience. Int J Oral Maxillofac Surg 2009;38:835-9. |
|11.||Bayar GR, Akcam T, Gulses A, Sencimen M, Ozkan A. Plating the Posterior Border of the Mandibular Ramus by Retro-Parotideal Approach in the Treatment of a Subcondylar Fracture. OHDMBSC - Vol. IX - No. 2 - June, 2010:98-102. |
Department of Oral and Maxillofacial Surgery, Annaswamy Mudaliar General Hospital, Bangalore
Source of Support: None, Conflict of Interest: None
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9], [Table 10], [Table 11], [Table 12]