Comparative Evaluation of Clinical and Radiological Outcomes of Retromandibular Transparotid and Transoral Endoscopic-Assisted Approach for Surgical Management of Mandibular Subcondylar Fractures

Abstract

Study Design: A prospective randomized comparative study was conducted to evaluate the clinical and radiological outcomes of the retromandibular transparotid (RMT) approach with endoscopic-assisted transoral (ENDO) approach used for open reduction and internal fixation (ORIF) of adult mandibular subcondylar fractures. Objectives: To evaluate and compare the primary functional outcome using the Helkimo’s dysfunction index, the surgical ease, the incidence of facial nerve weakness, the cosmetic outcomes and the number of complications following ORIF of mandibular subcodylar fractures using the RMT and ENDO approaches. Methods: In this prospective study, 20 patients with unilateral/bilateral subcondylay fractures requiring ORIF were recruited between 2017 and 2018. Patients were randomly divided into RMT and ENDO group, 10 patients in each. Clinical and radiological assessment was done preoperatively and in postoperative period it was done at different intervals over the period of 6 months. The intraoperative parameter time taken during surgery was correlated for association with the time elasped since day of trauma and with the fracture severity. Similarly, the presence of multiple fractures of the mandible and postoperative occlusion were evaluated for the association. Results: Comparable functional results were noted in both groups without any statistical significance. ORIF in ENDO group proved to be more time-consuming. For the RMT group, visible scars were rated best or close to best at the end of 6 months but a greater number of facial nerve injuries were reported in the RMT group. Conclusions: Superiority of one approach over others cannot be established since the outcomes were not statistically different. However, the ENDO approach appears to be safer. Therefore, there is a need for the development of innovative armamentarium which would improve the dexterity and ease of the surgeon and hence the total time taken for this minimally invasive approach for the management of subcondylar fracture.

Introduction

In the field of maxillofacial trauma, the mandibular condylar fractures are the most controversial regarding the diagnosis and treatment as reflected in the wide variety of opinions and proposed treatment modalities discussed in the literature.[1,2,3] The treatment of condylar fractures should target a maximum reduction of morbidity, postoperative complications, and esthetic and/or functional impairment.[4] After several years of debate, the consensus has been reached on specific indications for open reduction and internal fixation (ORIF) for condylar fractures, which include moderate to severely displaced fractures, angulated fractures over 10^◦, and dislocated subcondylar fractures in all patients except in growing children.[5,6,7] ORIF allows quicker functional rehabilitation of the temporomandibular joint. However, a risk of complications is associated with cutaneous surgical approaches like salivary fistula, visible scar, and temporary and permanent facial nerve damage.[5,6,7] There is, therefore, an absolute need to develop a surgical technique which will not only minimize the risks associated but also fulfil the following needs like giving widest possible exposure of the entire length of fracture, good access to either side of the fracture line, enough room for manipulation of the displaced or dislocated condylar fragment, enable adequate control of fractured condylar fragment after reduction, causes minimal disruption of soft tissue, minimal morbidity to facial nerve, and minimal other postoperative complications. Myriad of approaches have been tried over the last 2 decades to achieve the desired goals for surgical management of condylar fracture. Out of these, the salient one is retromandibular transparotid (RMT) approach, which accesses the fracture through the least working distance.[8] However, it carries the potential risk to the facial nerve and can cause various degrees of scarring.[9] In recent years, endoscopic-assisted transoral (ENDO) approach has been gaining ground, as it allows fixation of condylar fractures via an intraoral incision. Using an endoscope is supposed to provide excellent visibility and access to the subcondylar area while avoiding the inherent complications of extra-oral approaches like scarring and facial nerve damage.[10] However, endoscopic approach is supposed to have a steep learning curve with the need for dexterity to work under indirect vision in a narrow surgical field and limited optical cavity, distorted perspective and geometric constraints for instruments.[4] Therefore, the purpose of this prospective study was to evaluate and compare the clinical and radiological outcomes of RMT and ENDO approach for surgical management of mandibular subcondylar fractures.

Patients and Methods

All the patients were treated in the Department of Oral and Maxillofacial Surgery between March 2017 and August 2018. Patients were randomized into 2 groups, that is, RMT group and ENDO group with 10 patients in each. All patients were explained in the language they understood, the aim and objectives, procedure, follow-up, investigations, and possible adverse effects. They were given a detailed patient information sheet and informed consent was sought. All the protocols were approved by the institutional ethical review committee.

Inclusion criteria

• Patients in the age group of 18-60 years.
• Noncomminuted laterally displaced unilateral subcondylar fractures with more than 2 mm overlap and/or >10^◦ angulation with or without other concomitant fractures of mandible and with sufficient dentition to reproduce the occlusion.
• Bilateral mandibular condylar fractures where only one side warranted open reduction.
• The time gap between the day of trauma to admission in the hospital should be <3 weeks.
• Subject consent to participate.

Exclusion criteria

• Patients with a history of uncontrolled diabetes mellitus, prolonged steroid therapy, compromised immunity, and associated bone pathology.
• Intracapsular condylar fracture, undisplaced fractures of mandibular condyle, comminuted mandibular condylar fracture, concomitant pan facial or midface fracture, and history of previous mandibular fractures or osteotomies.
• The tendency for keloid formation and those with contused lacerated wounds, abrasions or avulsive soft tissue injuries around the area of extra-oral incision, and presence of preinjury or postinjury facial nerve palsy.

Additional fractures of the mandible were treated by ORIF independent of randomization. Following clinical parameters were assessed at follow-up:

• Helkimo’s dysfunction index—It consisted of 2 parts: the anamnestic index—a structured questionnaire for subjective assessment and a clinical dysfunction index based on clinical examination.[8,11]
• Occlusion: in the postoperative period: 0: intact, 1: altered occlusion which could be adjusted with intermaxillary elastics and intermaxillary fixation (IMF), 2: altered occlusion could not be adjusted by intermaxillary elastics or IMF and required reoperation.
• Scar: Stony Brook scar assessment scale[12] was used (0: worst and 5: best). Three blinded observers individually rated the scar. The interobserver reliability test was done to see the strength of agreement between raters.
• Surgical ease was evaluated by the time taken for surgery and also by a variable fracture severity score (FS), which correlated the severity of fracture and time taken during surgery. This included a preoperative score of mandibular mobility index, loss of ramus height, and degree of displacement (FS: 0-3 = Less Severe, 4-5 = Moderately Severe, 6-7 = Very Severe).
• Facial nerve injury: House Brackman facial nerve grading scale was used (0: Normal, 1: Normal, 2: Slight Dysfunction, 3: Moderate Dysfunction, 4: Moderately Severe Dysfunction, 5: Severe Dysfunction, 6: Total Paralysis).[9]
• Time elapsed since the day of trauma and time taken for surgery were correlated for the association. Similarly, the presence of multiple fractures of the mandible and postoperative occlusion were evaluated for the association.

Additional documentation included patient demographics and baseline characteristics (ie, description of trauma, fracture characteristics, concomitant soft tissue injuries, and the details of surgical procedures). Intraoperative complications recorded were excessive bleeding requiring blood transfusion. The follow-up examination was performed on immediate postoperative days, at 1 week, 1 month, 3 months, and at 6 months.

These observations were recorded by the same observer, who was blinded to the study, except for scar evaluation, which was done by 3 blinded observers.

Radiographic Assessment

Radiographs were taken postoperatively at 1 month, 3 months, and 6 months to assess the accuracy of the fracture reduction and the stability of the fixation.

Pre- and postoperative degree of displacement and pre-operative direction of displacement were assessed on Towne’s radiograph[13] (Figure 1) whereas pre- and postoperative loss of ramus height[13] (Figure 2) and distorted condylar morphology and presence of other concomitant mandibular fractures preoperatively were assessed on the panoramic radiograph. The distorted condylar morphology was defined as any distortion or irregularity in the condylar surface.

After establishing stable maxillo-mandibular fixation, occlusion, and dentition, the mandibular subcondylar fractures were treated.

Statistical Analysis

All statistical analyses were performed using the SPSS software. Categorical data were represented using frequencies and percentages and continuous data were described using means and standard deviations. Normality of data was checked by both visual inspections of histograms and Shapiro-Wilks test.

For categorical data, a χ² test was used and for continuous data, t-tests were used. For comparisons of data collected over multiple intervals of time, a general linear model of repeated measures analysis of variance (ANOVA) was used and pairwise comparisons were done using Bonferroni’s method. The intraclass correlation coefficient was used to check the inter-rater reliability. Relationship between variables was assessed using Spearman’s rank correlation coefficient. An a-level of .05 was used as a cut-point for statistical significance along with 95% confidence intervals.

Surgical Procedure

The Retromandibular Transparotid Approach

An incision of 4 to 5 cm length was placed just behind and parallel to the ramus of mandible and 1 cm below the ear lobe (Figure 3).[14] Facial nerve branches, if encountered, were carefully dissected out for a short distance and retracted either superiorly or inferiorly.[15] The stable occlusion was assured before the miniplate was fixed to the subcondylar portion of the ramus (Figure 4). The subcondylar fracture was subsequently reduced and fixed by two 2-mm titanium miniplates (KLS Martin).

Endoscopic-Assisted Transoral Open Reduction and Internal Fixation

A posterior buccal sulcus incision paralleling the oblique line of the mandible was made and extended up to the coronoid process along the anterior border of ramus. Subperiosteal dissection was done to strip the masseter off the lateral ramus and proximal body and a potential optical cavity were created.[4] The endoscope was introduced through the mouth, and an endoscope-mounted retractor was used to maintain the optical cavity (Figure 5). The segments were reduced and fixed with two 2.0-mm titanium miniplates (KLS Martin). The alignment was endoscopically checked after fixation. In case direct confirmation of condylar fractures was not possible, the plates were fixed under endoscopic guidance (Figure 6). All cases underwent fixation by an ENDO approach using transbuccal incision. In 2 cases of ENDO group, a supplementary incision below the angle of the mandible had to be given to facilitate distraction of the ramus.

Results

Demographic Results

The mean age at the time of injury was 27.1 years. There were 17 males (85%) and 3 females (15%) with male:female ratio of 6:1. The leading cause of trauma was road traffic accidents, that is, in 17 patients (85%).

There was no statistically significant difference in age, gender, etiology, and diagnosis between the 2 groups (Table 1 and Table 2).

Clinical Results

• Helkimo dysfunction index. This is a systematic tool to assess the functional status of temporomandibular joint (TMJ) and quantifies the dysfunction present and allows for correlation between the patient symptoms and clinical finding.

The overall comparison of the Helkimo’s dysfunction index score showed a significant improvement within the groups. However, no significant difference was found between the groups in anamnestic index at 1 month, 3 months, and 6 months (P = .302, P = .890, and P = .356, respectively) and neither was there any significant difference in the clinical dysfunction (P = .753, P = .958, and P = .783, respectively). Only 1 patient in the ENDO group had severe dysfunction at the end of 6 months (Table 3). No patient in either group presented with the deterioration of their condition in both groups at each follow-up.

• Occlusion. Preoperative occlusion was deranged in all 20 cases.

Postoperatively, at 1 week (n = 7) patients had altered occlusion, 4 in the ENDO group, and 3 in the RMT group (P = .693), which could be adjusted with elastics. At the end of 1 month, 1 case out of 4 and 2 out of 3 cases regained occlusion, while (n = 4) still had altered occlusion (P = .264). However, at the end of 3 months, all patients had intact occlusion. There were no cases where re-operation was required.

Table 1. Distribution of the participants of both groups according to age and gender.

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

Table 1. Distribution of the participants of both groups according to age and gender.

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

• Scar. For the RMT group, three blinded observers individually rated the scars. Based on the 95% confident interval of the ICC estimate, there was a statistically significant agreement between raters, ICC = .801 (95% CI, 0.949 to 5.292), P = .001. The strength of agreement was classified as very good reliability. A repeated measure ANOVA test showed that the scar assessment scale significantly got better over time F(1.68) = 35.335, P < .001.

At the end of 6 months postoperatively, all the scars were rated as best or close to best on the scar evaluation scale.

• Surgical ease. The mean time taken in RMT group was 63.5±12.48 minutes, whereas the mean operative time taken in ENDO group was 196.6 ± 48.9 minutes. The mean operating time for ORIF by RMT approach was 3 times faster than the ENDO (P < .001). An attempt was made to see if the severity of fracture positively correlated with the amount of time taken for surgery. A fracture severity score (FS) was developed and showed no statistically significant difference between the groups (P = .811). Only 2 patients in ENDO group experienced a surgical or technical complication during the procedure where the fracture fragments were grossly overlapped and for reduction, a supplementary incision was given near the lower border to facilitate the reduction (Table 4).

Table 2. Distribution of the participants of both groups according to etiology.

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid; RTA, road traffic accident.

Table 2. Distribution of the participants of both groups according to etiology.

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid; RTA, road traffic accident.

• Facial nerve injury. Temporary facial nerve weakness was an innate complication of the RMT approach, especially of the marginal mandibular and buccal branches. At the end of 6 months follow-up, recovery of the facial nerve damage was noted in 5 (P = .003) out of 6 patient in RMT group and in ENDO group only 1 patient had facial nerve weakness, which recovered fully at the end of 6 months. There was a significant improvement in grades over time (P = .001) for both groups.
• Correlation between parameters. Spearman’s correlation showed no relation between number of fractures and postoperative occlusion at 1 month, 3 months, and 6 months for both the groups (r = .320, P = .192; r = .223, P = .092, and r = .122, P = .568, respectively). Whereas a moderate relation was found between time elapsed since trauma to surgery and time took for surgery (r = .458), which was statistically significant (P = .042). This means that the delay in instituting treatment increased the time taken during surgery.

Table 3. Correlation between time taken in surgery and fracture severity score in both groups.

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

Table 3. Correlation between time taken in surgery and fracture severity score in both groups.

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

Table 4. Table showing intergroup comparison of number of patients according to Helkimo’s anamnestic dysfunction index and Helkimo’s clinical dysfunction index postoperatively at 1 month, 3 months, and 6 months and level of significance.

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

Table 4. Table showing intergroup comparison of number of patients according to Helkimo’s anamnestic dysfunction index and Helkimo’s clinical dysfunction index postoperatively at 1 month, 3 months, and 6 months and level of significance.

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

Table 5. Assessment of post op degree displacement in both the groups over different time periods.

Mean + SD (◦)		Pre-op	1 month	3 month	6 month
Degree of displacement	RMT group (n = 9)	18.0 + 11.0	3.6 + 3.7	2.6 + 3.3	1.4 + 1.66
	ENDO group (n = 9)	19.7 + 11.91	3.6 + 4.1	2.6 + 2.3	1.2 + 1.71
	Overall (n = 18)	18.8 + 11.17	3.6 + 3.8	2.6 + 2.7	1.3 + 1.6
P values (A vs B)		0.762	1.0	1.0	0.784
P values (over time)	P > .001

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

Table 5. Assessment of post op degree displacement in both the groups over different time periods.

Mean + SD (◦)		Pre-op	1 month	3 month	6 month
Degree of displacement	RMT group (n = 9)	18.0 + 11.0	3.6 + 3.7	2.6 + 3.3	1.4 + 1.66
	ENDO group (n = 9)	19.7 + 11.91	3.6 + 4.1	2.6 + 2.3	1.2 + 1.71
	Overall (n = 18)	18.8 + 11.17	3.6 + 3.8	2.6 + 2.7	1.3 + 1.6
P values (A vs B)		0.762	1.0	1.0	0.784
P values (over time)	P > .001

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

The mean time elapsed since the day of trauma before surgical intervention in the RMT group was 10.9 days and in ENDO group 7.9 days.

• Complications. During the follow-up period, surgical complications like formation of salivary fistula, sialocele, Frey’s syndrome, infection were not encountered in any of the cases.

Radiographic Results

Preoperatively, there was no statistically significant difference for the presence of other concomitant mandibular fractures (χ² = 2.118, P = .093) and severity of fractures (χ² = 1.143, P = .565) between the 2 groups.

The preoperative average degree of condylar displacement with SD in the RMT group was 18.0 ± 11, which improved to 1.4 ± 1.66 at the end of 6 months postoperatively. In the ENDO group, the preoperative average degree of condylar displacement with SD was 19.7 ± 11.91, postoperatively it improved to 1.2 ± 1.71 at 6 months (Table 5).

The average loss of ramus height with SD preoperatively was 4.30 ± 2.9 mm in the RMT group and 3.90 ± 2.2 mm in the ENDO group. It was reduced to 1.70 ± 1.4 mm and 0.80 ± 1.5 mm in RMT and ENDO group respectively at 6 months postoperatively. There was no significant difference between the groups at any interval of time (P > 0.05) for loss of ramus height and degree of condylar displacement (Table 6).

Two cases of condylar resorption were seen, 1 in the RMT group and 1 in the ENDO group at the end of 3 months and at 6 months follow-up, respectively (P = 1.000). These 2 patients were excluded from other pre- and postoperative radiographic calculations.

Discussion

The subjective and objective functional clinical outcomes of ORIF have yielded better long-term results as compared to closed treatment.[1,16] However, a list of complications is associated with the surgical approaches like salivary fistula, visible scar, and temporary or permanent facial nerve damage.[5,7] As suggested by followers of surgical philosophy, minimally invasive surgery namely ENDO approach is likely to eliminate the disadvantages of traditional extraoral surgical methods, however, due to the associated technical requirements, still it has not accepted as a routine surgical procedure.[17] Therefore, the purpose of this prospective study was to evaluate and compare the clinical and radiological outcomes of RMT and ENDO approach for surgical management of mandibular subcondylar fractures. The specific aim of this study was to help in decisionmaking regarding the choice of approach best suited for surgical management of adult Mandibular Subcondylar fracture.

Table 6. Assessment of loss of ramus height in both the groups over different time periods.

Mean + SD (mm)		Pre-op	1 month	3 month	6 month
Loss of ramus height	RMT group (n = 9)	4.30 + 2.9	2.30 + 1.4	1.90 + 1.5	1.70 + 1.4
	ENDO group (n = 9)	3.90 + 2.2	1.70 + 1.4	1.60 + 1.7	0.80 + 1.5
	Overall (n = 18)	4.10 + 2.5	2.00 + 1.4	1.75 + 1.6	1.25 + 1.5
P values (A vs B)		.734	.357	.690	.192
P values (over time)	P > .001

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

Table 6. Assessment of loss of ramus height in both the groups over different time periods.

Mean + SD (mm)		Pre-op	1 month	3 month	6 month
Loss of ramus height	RMT group (n = 9)	4.30 + 2.9	2.30 + 1.4	1.90 + 1.5	1.70 + 1.4
	ENDO group (n = 9)	3.90 + 2.2	1.70 + 1.4	1.60 + 1.7	0.80 + 1.5
	Overall (n = 18)	4.10 + 2.5	2.00 + 1.4	1.75 + 1.6	1.25 + 1.5
P values (A vs B)		.734	.357	.690	.192
P values (over time)	P > .001

Abbreviations: ENDO, endoscopic-assisted transoral; RMT, retromandibular transparotid.

The visibility provided by the surgical approach and number and type of internal fixation hardware used to play an important role in performing a correct and stable anatomic reduction and fixation. Nevertheless, it may be pertinent to point out that owing to the mandibular anatomy the visibility of the dorsal aspect of the ascending ramus and control of fracture reduction was challenging in some cases with the endoscopic approach. Hence careful selection of fractures with only lateral overlap for operative treatment is essential when the endoscopic approach is to be adopted to avoid intraoperative difficulties and complications. Two participants in the endoscopic group who had gross overlap posed a challenge for accurate reduction with repeated slippage of the condylar fragment medially, they needed a supplementary extra-oral incision for passage of wire for the inferior distraction of ramus. Postoperative radiographs showed accurate reduction and anatomical position of the condylar fragment with no gap between the segments in both groups.

Schmelzeisen et al reported that operating time was 33 minutes more in ENDO group as the transoral approach is subject to a learning curve and it requires intensive training of endoscopic technique and handling of instruments.[8] In this study, the mean operating time for the RMT group was 3 times faster than that for the ENDO group. A variable fracture severity score was derived which showed that there was no significant correlation between the fracture severity and time taken in both the groups (t(18) = 8.335, P < 0.001). The fractures were of comparable severity in both groups but still endoscopic approach took a longer time which indicated that it was technically more difficult to perform. The subjective limitation included the surgeon’s experience and the steep learning curve. Few of the main pitfalls were the poor medial control of the condylar fragment, poor direct visualization, and need for right-angled manipulation. Therefore, there may arise such situations during endoscopic repair when the surgeon may have to take a judicious decision whether to continue the endoscopic effort or bailout and adopt the traditional retromandibular approach for completion.[4] The following points are suggested for future consideration for greater versatility of use of ENDO approach:

(a)

Consider design and use of instruments which may facilitate 3D control of the condylar fragment postreduction while at the same time not interfering with the optical cavity.

(b)

Coronoidectomy may allow a direct visualization of the condylar fracture site when transoral route is adopted.

The primary functional outcome was evaluated using the Helkimo dysfunction index, which was recorded for each patient. Helkimo dysfunction score consists of 2 indexes (ie, anamnestic, clinical dysfunction) which was satisfactory, as most of the patients having low scores at 6 months. No significant differences were found in these functional scores between the ENDO and RMT groups. Schmelzeisen et al have reported similar results in a randomized control trial.[8] The stable functional results obtained after ORIF using the RMT and ENDO approaches showed a comparable quality of the reduction and fixation obtained for both treatment groups.

The incidence of facial nerve paresis in the literature varies from 8% to 19% for retromandibular approach.[5] The exact reason for facial nerve weakness was not established in both the group. In ENDO group postinjury edema because of longer operative time and soft tissue manipulation may probably be the cause for facial nerve weakness. Temporary facial nerve palsy during the postoperative periods was noted in 1 ENDO patients and 6 RMT patients. A tendency was shown toward an increased number of ORIFtreated patients with facial nerve damage. However, all patients except one were fully recovered in the last follow-up examination. Bhutia et al concluded that the RMT approach is useful for treating undisplaced and laterally displaced Subcondylar fractures, and it has the advantages of direct access to the fracture site, an inconspicuous scar, no permanent damage to the facial nerve, and easy ORIF.[18]

The presence of a visible scar on the face reduces, without doubt, the value of open treatment of condylar fracture. In the present study, at the end of 6 months, postoperatively all scars in ORIF group reported best or close to best. This reduces the significance of scars in the decision-making for use extra-oral approaches and overall satisfaction of the patient.[8] It was suggested that in women with high esthetic expectation a rhytidectomy incision may be combined with RMT approach for the better cosmetic outcome.[19]

The level of fracture influences the degree of preoperative coronal and sagittal displacement of the proximal condylar fragment, which in turn contributes to disturbances in occlusion. One of the most important criteria for treatment of Subcondylar fracture is restoring the pretraumatic occlusion. Though the radiographic finding immediately postoperatively and on follow-up suggested satisfactory anatomical reduction, still few participants in both groups suffered altered occlusion in the initial period. This means that accurate repositioning of the fracture segments does not necessarily guarantee a correct physiological position of the condyle in the fossa.[2] Moreover, the more rigid the fixation of the condyle in even subtly altered positions, higher the risk of postoperative remodeling and dysfunction as a result of increased loading in an altered condylar position. However, irrespective of age, functional remodeling and adaptation always occur in the condyle which explains the fact that participants who required IMF with elastic in initial postoperative time period achieved normal occlusion after 3 months. No statistically significant difference existed in the occlusal status between the 2 groups.

Re-establishment of the vertical ramus dimension is one of the important aims of open reduction. In the present study, good visibility of the fracture site and precise intraoperative control after fixation were obtained in most cases of both the groups, which is reflected by good postoperative clinical and radiological findings. In our study, the loss of ramus height and direction of displacement of condylar fragment significantly improve in both the groups.

It has been theorized that in case of mandibular condylar fractures, the medullary blood supply is disturbed and the other sources become dominant, in other words, rapid retrograde flow and hypervascularity through the muscular and capsular ligamentous attachments compensate for this interruption in blood flow. Stripping of all soft tissue supply, therefore, will inevitability result in vascular ischemia, necrosis and ultimately some form of regeneration which is unpredictable.[20] Degeneration of joint may occur with damage to the disk, altered loading, or devascularization of the proximal segments. In this study, we have experienced 2 cases of condylar resorption 1in each group, In the RMT group, it was evident at the end of 3 months whereas in ENDO group it was seen at the 6 months follow-up. As it presented in both groups, the reasons for the resorption not can be attributed to any particular approach. It was perhaps the excessive dissection of surrounding tissues and manipulation of the proximal fragment thereby avulsing the soft tissue attachments that could have contributed to the resorption.[21] Hence it is imperative to preserve and respect the surrounding soft tissue attachments to prevent such long-term outcomes. Long-term radiological results after open reduction of mandibular condyles highlighted that intraoperative repositioning of just the fracture borders along the condylar neck may not guarantee the correct 3Dphysiological positioning of the condyle in the fossa. Besides rigid fixation in this altered position may lead to long-term condylar resorption.[22]

Open techniques around the temporomandibular joint are at risk of potential bleeding from the maxillary artery, masseteric artery, and the retromandibular vein.[23] In our study, intraoperatively no patient had excessive hemorrhage requiring blood transfusion. However, it was observed that even subtle bleeding while manipulating around the joint obscured the vision, needed suctioning and clearing of the scope ends thereby adding to the intraoperative time during the endoscopic approach.

The main shortcomings of the study were that the sample sizes were not large enough to draw a definite conclusion and the sample population selected were only exclusively subcondylar fractures with lateral override, while condylar fractures in reality display a wide range of patterns. Three-dimensional computed tomography or cone beam computed tomography was not included in the study protocol because of cost concern. Most of the functional and structural implication of ORIF may surface only after the joint resumes its full range of function and loading which normally happens after 3 to 6 months. Though condylar distortion and resorption were evident in 6 months follow-up radiograph in 1 case in either group, it may be prudent to have longer follow-up before making inferences on the long-standing effects like avascular necrosis, structural remodeling, and compromise to soft tissue components all of which would contribute to the late dysfunction. It is recommended that future research should come up with innovative armamentarium design which would improve the dexterity and ease of the surgeon in minimally invasive approaches and hence reduce overall operative time.

Conclusion

Within the limitations of this study, the results show that comparable clinical and radiological outcomes obtained with both the approaches. However, the RMT approach was 3 times faster in the operating room. No scar formation and lower incidence of facial nerve damage were the advantages of ENDO approach but it has a steep learning curve and requires intensive training. As ENDO approach appears to be more safe as less complications were associated with it, with the development of innovative armamentarium which may improve the handiness and ease of surgeon, may help this approach to become more popular and surgeon friendly.