Clinical experience with osteosynthesis of subcondylar fractures of the mandible using TCP plates

Postoperative Complications following Open Reduction and Rigid Internal Fixation of Mandibular Condylar Fracture Using the High Perimandibular Approach

The high perimandibular approach is a feasible surgical technique for treating mandibular condylar fractures with open reduction and internal fixation, followed by fewer complications. Temporary trismus is the only postoperative complication that may occur. This study evaluated postoperative complications following open reduction and rigid internal fixation (OR-IF) of mandibular condylar fractures using the high perimandibular approach. Twenty consecutive patients undergoing OR-IF were included in this study. They included 11 male and 9 female patients, of an average age of 58.5 years, all of whom responded to a follow-up call at least 12 months after the surgery. All patients were evaluated for range of mouth opening, postoperative complications, and radiological findings. A statistical analysis of the relationship between range of mouth opening and related clinical parameters at 6 months postoperative evaluation was conducted. The fracture of the condylar neck was associated with a limited range of mouth opening and longer operation time. However, longer operation time was not associated with a limited range of mouth opening. The high perimandibular approach with OR-IF in mandibular condylar fractures is a feasible and safe technique; however, prolonged surgery and mandibular condylar neck fractures could affect the postoperative range of mouth opening.

A, Srivastav S, P.G. G, Kumar P, Chaudhry K. Treatment Outcome Comparison Between two 3-Dimensional Plates (Y-Shaped Plate Versus Trapezoidal Condylar Plate) in Management of Mandible Condylar Fracture: A Randomized Control Trial

Aim

To compare the treatment outcomes (clinical, functional and radiographical) using the two different 3-Dimensional plates in open reduction internal fixation of mandibular condylar fracture (MCF). Assessment of ease of fixation and fixation time were also performed.

Methodology

20 MCF patients were divided equally into two groups (Group A: Trapezoidal Condylar Plate and Group B: Y-shaped plate) and the treatment outcomes were compared. Intraoperatively time required for fixation was also compared. The patients were followed up at different timelines till 3 months.

Result

Baseline parameters had statistically insignificant distribution in both groups implying effective randomization and balanced confounding factors. Intraoperatively, adequate anatomical reduction was achieved in both groups with statistically insignificant difference in time required for fixation. Postoperatively, no statistically significant difference was found in radiographic and functional parameters. None of the patients in either group reported with facial nerve injury, condylar resorption, Temporomandibular Disorders. However, 02 patients in Group A and 01 patient in Group B presented with infection, parotid fistula, and hardware failure respectively with statistically insignificant difference.

Conclusion

This study concluded that the treatment outcomes were satisfactory with the use of both 3-D plate, but further studies with larger sample size and longer follow up are required.

Analysis of the High Submandibular Approach: A Critical Reapprasail of a Transfacial Access to the Mandibular Skeleton

AIM

In 2006 following the development of dedicated osteosynthesis plates, Meyer and colleagues reported a successful clinical study of condylar fractures treated by a modified submandibular approach; it was called high submandibular approach or "Strasbourg approach." The aim of this study is to describe the high submandibular approach step by step.

CASE SERIES

Between January 2010 and December 2015 at the Maxillofacial Unit of the Hospital "Policlinico San Martino" 13 patients affected by subcondylar fracture underwent open reduction and internal with high submandibular approach. Surgery was uneventful in all patients; no infections occurred in any of the cases; the mean procedure duration was 89 minutes, ranging from 66 to 125 minutes. The mean hospital stay was 2.9 days, ranging from 2 to 6 days. At the 1-year follow-up, all patients had stable occlusion with a natural, well-balanced morphology of the face and adequate dynamic excursion of the mandible.

CONCLUSIONS

The morbidity is negligible in terms of damage to the facial nerve, vascular injuries, and aesthetic deformity. The authors think that further prospective clinical trials are necessary to assess and eventually develop this approach.

Preauricular anteroparotid transmasseteric approach of the mandibular condyle: The natural evolution after cervical dissections? An anatomical feasibility study

The purpose of this study was to evaluate the reliability and reproducibility of a novel approach for base and neck fractures of the mandible. An anatomical study was conducted on 22 given to Science subjects. A rhytidectomy-like approach was performed, followed by a transmasseteric anteroparotid dissection. Measures were taken of the incision length and bone exposure at every step. The identification of a ramus of the facial nerve during dissection was noted. The subjects were classified according to their facial adiposity. A correlation coefficient was measured between incision length and bone exposure as well as morphotype and bone exposure. Statistical analysis was carried out using the Pearson method for linear correlation, and Chi2 test for further analysis. Adequate condylar exposure was always achieved in the area of interest (i.e. in the main localization of base and neck fractures). There was no correlation between the length of the cranial cutaneous backcut and the bone exposure horizontally (p = 0.3296) or vertically (p = 0.8382). There was no correlation between the total length of the incision and the bone exposure horizontally (p = 0.5171) or vertically (p = 0.8404). There was a significant correlation between the subjects' facial adiposity and the bone exposure horizontally and vertically (p<0.005). This approach allowed adequate bone exposure to the mandible base and neck, with a possible 90° angulation of instruments for optimal bone fixation. The incidence of facial nerve rami identification during dissection was similar to other approaches. The scarring was hidden. These results allowed us to propose this approach in a clinical study.

Pre-auricular Transparotid Approach for the Management of Mandibular Condylar Fracture: An Experience of 82 Cases

Purpose

This paper retrospectively analyses the functional outcomes and complications associated with pre-auricular transparotid approach for the management of mandibular condylar fractures.

Material and Methodology

The retrospective data of 82 condylar fractures were analysing in 73 patients who underwent open reduction and internal fixation with pre-auricular transparotid approach. Evaluation of post-operative complications and the post-operative occlusion status, maximal inter-incise opening, adequacy of reduction and stability of fixation were assessed clinically and radiographically.

Results

The exposure of fracture segment was adequate in all the cases, and fixation was easy with 2 mm delta miniplate. Transient facial nerve palsy occurred in 2 patients (2.43%). 1 patient developed sialocele which was managed conservatively. There were slight occlusal discrepancies in 10 patients at the end of 1-week follow-up which was corrected with guiding elastics at the end of 1-month follow-up. The reduction was adequate, and fixation was stable. The functional outcomes were satisfactory in term of mouth-opening and range of motion.

Conclusion

The pre-auricular transparotid approach provides direct access to the fracture site resulting in less retraction of the tissue containing facial nerve and also less amount of periosteal stripping is required, thus it maintains good vascularity to the fracture segments. It provides direct visualization of the fracture without much retraction of the tissue containing facial nerve branches. It allows better fixation of the fracture with very less complication which results in good functional outcomes.

Finite element analysis of different titanium miniplates: Evaluation of three-dimensional designs applied on condylar neck fractures

INTRODUCTION

The fixation of condylar neck fractures is raising difficulties and for this reason, many plate designs have been developed. The current study compares the performance of four miniplates used in the condylar neck.

MATERIAL AND METHODS

A virtual condylar neck fracture in a mandible obtained from a CT scan was fixed with four miniplates (two straight miniplates, lambda, strut, and trapezoidal). Using finite element analysis, we examined the fragments' displacements and stress distribution in the titanium material and bone. The models were analyzed under two loading conditions: a reduced bite force of 135 N and a force of 500 N.

RESULTS

No risk of material failure was observed. For a load of 135 N, all four plates offer an adequate fixation. For 500 N of applied loading, the lambda and strut plates showed the best rigidity and lowest bone strains. The two parallel plates showed the lowest rigidity and the trapezoidal plate the highest bone strains around all screws.

DISCUSSION

These findings imply that three-dimensional miniplates (lambda, strut) perform better when higher loads are applied. On the other hand, the trapezoidal plate has an increased risk of screw loosening and the two straight plates higher mobility of the fragments.

Evaluation of 3D Trapezoidal Plates in Open Reduction and Internal Fixation of Subcondylar Fractures of Mandible: A Clinical Trial

Background  Fractures of the mandibular condyle are common and account for 25% to 50% of all fractures of the mandible. Various methods exist for open reduction and internal fixation (ORIF) of condylar fractures. This study was done to explore three-dimensional (3D) plates as a viable option. Aim  This study aims to evaluate the effectiveness of 3D trapezoidal plates in open reduction and internal fixation of subcondylar fractures. Materials and methodology This was a non-randomized clinical trial conducted on 20 patients who reported at the Department of Oral and Maxillofacial Surgery, Tamil Nadu Government Dental College and Hospital, Chennai, India. The ORIF was done under general anesthesia. A retromandibular transmasseteric approach was used to expose the fracture site, and the fracture was stabilized using 3D titanium trapezoidal plates. Parameters, such as mouth opening, mandibular deviation, occlusion, surgical accessibility, fracture reduction, adaptability, the difference in ramal height, angulation of the fractured condyle, operative time, facial nerve weakness, implant failure, complications, and scar formation were assessed. Statistical analysis was done using Statistical Package for Social Sciences (SPSS), version 21 (IBM SPSS Statistics for Windows, Armonk, NY). Results  There was an improvement in mouth opening and occlusion in the immediate postoperative period. The surgical accessibility ranged from good to excellent. The fracture reduction was excellent in 60% of patients and good in 40%. In one patient, there was a transient weakness of the marginal mandibular nerve which recovered by three months. Another patient had a wound infection that subsided within the first postoperative week. None of the patients had a device failure during the six-month follow-up period. Conclusion  The trapezoidal 3D plates could be considered as a viable option for treating subcondylar fractures of the mandible in terms of surgical accessibility, stability, ease of device placement, stability of reduced fracture, reduced osteosynthesis material requirement, and minimal damage to the surrounding tissues.

Stability of bioabsorbable fixation systems according to different locations of mandibular fracture: A three-dimensional analysis

This study aimed to elucidate whether the stability of an unsintered hydroxyapatite particles/poly-_l-lactide (uHA/PLLA) system is comparable with that of titanium, according to different load-bearing areas of the mandible. The study included patients who underwent open reduction and internal fixation of the mandibular body, angle, or subcondylar fracture. The stability of uHA/PLLA systems was compared between the immediate and 6-month postoperative time points using three-dimensional cone-beam CT image analysis. The positional changes of each landmark were measured in three-dimensional (3D) coordinate systems using simulation software. Among 36 patients, there were more displacements of the landmarks between the immediate and 6-month postoperative time points after subcondylar fracture reduction than after body or angle fracture reductions. Strong upward displacements of the landmarks after subcondylar fracture reduction were found in the lateral pole [mean (SD) = 1.75 (3.16), p-value = 0.003] and medial pole [mean (SD) = 1.64 (2.50), p-value = 0.024], but not in the center. Subgroup analyses revealed similar unstable results in males on the condylar landmarks after subcondylar fracture reduction. There were tendencies for lateral displacement of the coronoid process in the body fracture group [mean (SD) = 0.8 (0.83)] and angle fracture group [mean (SD) = 0.75 (0.58)] postoperatively (p-value = 0.01). This study concluded that bioresorbable osteosynthesis can be recommended for body or angle fractures, while the indication for subcondylar fractures is less clear.

Two miniplates versus 3-dimensional plate in the management of mandibular subcondylar fractures: a retrospective analysis

PURPOSE

The aim of the present study was to evaluate the outcomes in patients with subcondylar fracture of mandible treated with 2 single miniplates compared to a 3-dimensional (3D) plate.

PATIENTS AND METHODS

This is a retrospective study which included patients diagnosed and treated for mandibular subcondylar fracture from January 2015 to December 2019. Included patients were divided into two groups, group 1: 2 miniplate group and group 2: 3D plate group. The data was obtained from the patients' records and evaluated for various outcomes including occlusal stability, postoperative complications like plate fracture, non-union, plate or screw loosening, and plate or screw infection leading to implant removal, wound dehiscence, salivary fistula, and facial nerve paralysis. The statistical analysis was performed using chi square test and Student's t test.

RESULTS

A total 58 patients (43 males and 15 females) were enrolled in the two groups ranging from 21 to 59 years. A total of 35 patients were recruited in group 1, whereas 23 patients were recruited in group 2. There was no statistically significant difference in the two groups with regard to the age range, gender, diagnosis, side of fracture, and accompanying fractures. Occlusal instability, wound dehiscence, and facial nerve paralysis was found in both the groups. Group 1 had 1 patient which required implant removal due to screw loosing, whereas group 2 had 2 patients which required plate removal due to plate fracture. One patient in group 2 required second surgery for fixation of fracture due to non-union. One patient in group 1 developed a sialocele postoperatively. However, there was no statistically significant difference in any of the variables assessed among the two groups (p > 0.05).

CONCLUSION

The results of our study indicate that the 2 miniplates and 3D plate system are effective in the management of mandibular subcondylar fractures.

Change in Pull-Out Force during Resorption of Magnesium Compression Screws for Osteosynthesis of Mandibular Condylar Fractures

BACKGROUND

Magnesium has been used as degradable fixation material for osteosynthesis, but it seems that mechanical strength is still a current issue in these fixations. The aim of this study was to evaluate the axial pull-out force of compression headless screws made of magnesium alloy during their resorption.

METHODS

The tests included screws made for osteosynthesis of the mandible head: 2.2 mm diameter magnesium alloy MgYREZr (42 screws) and 2.5 mm diameter polylactic-co-glycolic acid (PLGA) (42 pieces, control). The screws were resorbed in Sørensen's buffer for 2, 4, 8, 12, and 16 weeks, and force was measured as the screw was pulled out from the polyurethane block.

RESULTS

The force needed to pull the screw out was significantly higher for MgYREZr screws than for PLGA ones (p < 0.01). Within eight weeks, the pull-out force for MgYREZr significantly decreased to one third of its initial value (p < 0.01). The dynamics of this decrease were greater than those of the pull-out force for PLGA screws (p < 0.05). After these eight weeks, the values for metal and polymer screws equalized. It seems that the described reduction of force requires taking into account when using magnesium screws. This will provide more stable resorbable metallic osteosynthesis.

Evaluation of Open Reduction and Internal Fixation of Mandibular Condyle Fracture by Intraoperative Cone-Beam Computed Tomography in a Hybrid Operating Room

Condylar fractures are the most common fractures of the mandible, and treatment of mandibular condylar fractures by maxillofacial surgeons is a very important procedure. However, the surgical approaches have anatomical limitations. Therefore, it is difficult to evaluate the reduction achieved in open reduction and internal fixation because of the uncertainty in securing a sufficient operative field. As a potential solution, the authors evaluated the benefits of intraoperative cone-beam computed tomography (CBCT) with high image quality performed in a hybrid operating room. Intraoperative CBCT is easy to perform in a hybrid operating room, and it is possible to quickly evaluate high-quality CT images, including 3D images. Because the state of reduction of mandibular condylar fractures also affects the prognosis of treatment, more precise reduction and fixation should improve prognoses. The use of CBCT in a hybrid operating room also avoids re-operation, and patients benefit from minimum invasive surgery. Intraoperative CBCT is a very useful strategy for evaluation of mandibular condylar fracture surgical treatment.

The high sub-mandibular approach: Our experience about 496 procedures

INTRODUCTION

The potential drawbacks of surgical approaches to neck and base fractures of the mandibular condyle (visible scare, facial nerve injury) are still considered by many surgeons as a brake for open reduction and internal fixation. The aim of our study was to analyze the results in terms of access, scare quality and complications that could be noticed in a 12 years period of time with the use of the high sub-mandibular approach (HSMA) we first described in 2006 for the surgical treatment of neck and base fractures.

MATERIAL AND METHOD

All the files of patients operated on for condylar neck and base fractures approached by mean of a HSMA between January 2006 and December 2018 in our department and containing information concerning age, sex, type of fracture, kind of osteosynthesis material, operating time, name of the surgeon, postoperative complication linked to the approach, scare quality at 6 months follow-up at least were included. The skin incision and the dissection planes followed the original publication of Meyer et al. in 2006.

RESULTS

434 patients (sex ratio: 2.06, mean age: 32, 496 approaches) met the inclusion criteria. Following the AO classification, 21.2% of the fractures were classified as neck fractures and 78.8% as base fractures. 97.6% of all fractures were stabilized by mean of a 3D plate (TCP® plate, Medartis, Basel-CH), the remaining ones by mean of a combination of 1.2, 1.5 and 2.0 straight plates. Mean operating time was 40minutes per side. Patients were operated on by senior surgeons in 71.7% of the cases and by trainees under supervision for the others. Concerning the complications linked to the approach, we noticed 11 (2.2%) temporary (0 definitive) paresis of the facial nerve, 1 (0.2%) hematoma and 1 (0.2%) abscess that both needed revision. Scare was hypertrophic or considered as unaesthetic by the patient in 5 cases (1%).

DISCUSSION

The HSMA, if performed as initially described, is a safe and quick procedure compared to other cutaneous approaches. It gives access to all base fractures and to most of neck fractures. The very low rate of facial nerve complications is mainly explained by the plane by plane dissection making it very easy to avoid the facial nerve branches or to check them when encountered. The HSMA is particularly suited to the use of TCP plates as the upper holes of these plates, placed horizontally, are easy to reach from below. The HSMA is therefore still our preferred cutaneous approach to the condylar process.

Variations in the retromandibular approach to the condyle-transparotid versus anteroparotid transmasseteric - a prospective clinical comparative study

BACKGROUND

The management of mandibular condylar fracture remains controversial many surgeons still favour the open reduction and internal fixation (ORIF) which provides good result and immediate functioning as compared to closed reduction. With proven consensus for ORIF, dilemma remains in choosing the surgical approach to condyle due to proximity of complex and important anatomic structure. Various extra-oral surgical approaches are available for ORIF including preauricular, submandibular, retromandibular, transmasseteric anteroparotid etc. Variations in retromandibular approach such as transparotid, retro-parotid and anteroparotid are reported in literature. In our study we compared the retromandibular transparotid and retromandibular anteroparotid transmasseteric variations.

METHODOLOGY

Thirty condylar fracture in 26 patients, 15 in each group (group A - Retromandibular transparotid approach & group B - Retromandibular anteroparotid approach) were treated under general anaesthesia with naos-tracheal intubation and by the same surgeon having 20 years of experience in maxillofacial surgeries. We evaluated time taken for the procedure, amount of bone exposure, intra-operative haemorrhage. Postoperative presence of infection, sinus and fistula formation at the incision site, parotid fistula formation, facial nerve functioning using House-Brackman scale in immediate postoperative period, 3^rd month postoperatively and 6 month postoperatively.

RESULT

The mean average time taken for group A was 78.2minutes and mean average time taken for group B was 64.8minutes. None of the patient had haemorrhage intra-operatively in both the groups. Exposure was sufficient in both the groups with same length of the incision. None of the patient suffered from postoperative infection in both the groups. Parotid fistula formation was present in 2 patients in group A while none of the patient had parotid fistula in group B. Three patients out of 15 had the transient facial nerve weakness in group A which got resolved in 6 month while none of the patient had facial nerve weakness in group B. All patients had adequate mouth opening with no occlusal discrepancies.

CONCLUSION

Retromandibular anteroparotid approach as described in this study has proven to be an extremely useful approach provides good access, and associated with minimal complications and morbidity compare to retromandibular transparotid approach. It is hence safe to say that this approach is relatively useful for an inexperienced and novice surgeon as well.

A comparative study of intraoral versus retromandibular approach in the management of subcondylar fracture

Background

The purpose of this study was to compare the outcomes and effectiveness between intraoral approach and retromandibular approach for treatment of subcondylar fracture of mandible.

Methods

Between March 2011 and October 2013, 24 patients with subcondylar fractures of the mandible were treated by a single surgeon with an intraoral approach using an angulated screwdriver (n = 14) or by another surgeon using a retromandibular approach (n = 10). The interincisal distance was measured 1 week (T0), 6 weeks (T1), 3 months (T2), and 6 months (T3) postoperatively. We also compare the average operation time and the cost of operation between the two groups.

Results

At 6 months postoperatively, all 24 patients achieved satisfactory ranges of temporomandibular joint movement, with an interincisal distance > 40 mm without deviation and with stable centric occlusion. The intraoral group had the median interincisal distance of 14 mm at T0, 38 mm at T1, 42.5 mm at T2, and 43 mm at T3, while the retromandibular group had that of 15, 29, 35, and 42.5 mm respectively. There was no statistically significant difference between the intraoral and the retromandibular group at T0 and T4. However, significant differences were noted T1 and T2 (p < 0.01). The differences of average operation time between the intraoral (81 min) and retromandibular group (45 min) were statistically significant (p < 0.01). The cost of an operation was 369.96 ± 8.14 (United States dollar [USD]) in intraoral group and was 345.48 ± 0.0 (USD) in retromandibular group. The differences between the two groups were statistically significant (p < 0.01).

Conclusion

In open reduction of a subcondylar fracture of the mandible, a intraoral approach using an angulated screwdriver is superior to the retromandibular approach in terms of interincisal distance, although the operation time is longer.

Surgical approaches for condylar fractures related to facial nerve injury: deep versus superficial dissection

The aim of this study was to investigate the probability of facial nerve injury (FNI) in the treatment of condylar neck and subcondylar fractures (CN/SCFs) with percutaneous approaches and to identify factors predicting FNI. The data of 80 patients with 87 CN/SCFs were evaluated retrospectively. The primary outcome was FNI occurrence. The predictor variables were age, sex, aetiology, alcohol consumption, fracture site and pattern (dislocation or not), concomitant fractures, time interval to surgery, surgeon experience, plate type, and the dual classification of percutaneous approaches. The approaches were classified based on whether subcutaneous dissection traversed the marginal mandibular branch (MMB) deeply (deep group: submandibular and retroparotid approaches) or superficially (superficial group: transparotid, transmasseteric anteroparotid (TMAP), and high cervical-TMAP approaches). Twenty-two patients (27.5%) suffered FNI, of whom two in the deep group had permanent paralysis of the MMB. In the multivariate logistic regression model, deeply traversing surgery approaches (odds ratio 12.4, P=0.025) and the presence of a dislocated fracture (odds ratio 6.66, P=0.012) were associated with an increased risk of FNI. These results suggest that percutaneous approaches in the superficial group should be recommended for the treatment of CN/SCFs to reduce the risk of FNI.

Which fixation methods are better between three-dimensional anatomical plate and two miniplates for the mandibular subcondylar fracture open treatment?

PURPOSE

To compare the clinical outcomes of a single three-dimensional (3-D) anatomical plate versus two conventional straight miniplates for the open treatment of mandibular subcondylar fractures.

METHODS

This retrospective clinical study included patients with mandibular subcondylar fractures treated by the retromandibular transparotid approach using a 3-D plate or two straight miniplates. Outcome variables included preoperative conditions of patients and fractures, extent of postoperative bone healing, and incidence of complications. Other variables included age, sex, fracture site, and follow-up duration. Variables were evaluated using descriptive statistics and compared between groups.

RESULTS

Twenty-eight fractures were analyzed: 13 fractures using 3-D plate and 15 fractures using two straight miniplates. None of the assessed variables showed significant differences between the two groups (p < 0.05). Unfortunately, in the 3-D plate group, reoperation was necessary for nonunion owing to plate breakage in one case with a bone defect around the fracture.

CONCLUSION

The 3-D plate and two straight miniplates were equally effective for the surgical management of mandibular subcondylar fractures. Although a 3-D plate is sufficient for a typical simple fracture, in cases with a bone defect around the fracture, selection of the plate fixation method should be carefully considered.

Does encountering the facial nerve during surgical management of mandibular condylar process fractures increase the risk of facial nerve weakness? A systematic review and meta-regression analysis

PURPOSE

The purpose of this study was to identify whether the incidence of systematically identified or incidentally encountered facial nerve branches during dissection to approach condylar fractures increases risk of transient and/or permanent facial nerve weakness.

METHODS

A systematic review and meta-analysis were performed that included several databases with specific keywords, a reference search, and a manual search for suitable articles. The inclusion criteria were all clinical trials, with the aim of assessing the rate of facial nerve injuries when open reduction and internal fixation (ORIF) of condylar process fractures was performed using different surgical approaches. The articles had to have documented the number of encountered facial nerve branches during ORIF. The main outcome variable was transient and permanent facial nerve injury. The dependent variable was the event and/or number of encountered facial nerve branches during surgery, and how they were handled (i.e. dissected, retracted, etc.).

RESULTS

A total of 1202 mandibular condylar fractures were enrolled in 29 studies. Rate of transient facial nerve injury (TFNI) was 11.3 % (136/1202). The number of facial nerve branches encountered intraoperatively was 543, namely buccal, marginal mandibular, zygomatic and temporal nerve branches. There was a significant correlation suggesting that there is a strong positive linear relationship between TFNI and encountered facial nerve branches (Coef = 0.1916, P = 0.001). There was no significant relationship between permanent facial nerve injury and encountered facial nerve branches (P = 0.808). TFNI was 4.3% and 18.7% for those studies expressly reporting that facial nerve branches were encountered incidentally without dissection and with dissection, respectively. For studies reporting deliberate and systematic facial nerve dissection, TFNI was 20.9%. Finally, studies that did not report any encounters of facial nerve branches, TFNI was 7.9 %.

CONCLUSION

This meta-analysis demonstrated that manipulation of the facial nerve during different surgical approaches causes different incidences of facial nerve injury. The choice of surgical approach for a given fracture should take this into consideration.

Nano-Biphasic Calcium Phosphate Ceramic for the Repair of Bone Defects

Calcium phosphate bioceramics has recently experienced increased interest in bone reconstruction. Mimicking of natural structure of bone, like the use of nanomaterials, is an attractive approach for generating scaffolds for bone regeneration. The aim of present study was to evaluate the effect of nanonization on the biphasic calcium phosphate (BCP) ceramic in the repair of bone cavities in the canine mandible. A commercial BCP was dry-milled in a high energy planetary ball mill with zirconia balls and container. Three holes (8 mm in diameter) were outlined to the depth of cortical bone of mandibular angle of 5 dogs bilaterally. The first hole (positive control group A, n = 10) was filled in with commercial BCP material. The second hole was loaded with the nanonized BCP (experimental group C, n = 10) and the third one was left untreated (negative control group B, n = 10). The defects were allowed to regenerate for 8 weeks. New bone formation was greater in groups A and C than in B. No difference was seen between group A and group C (P = 0.676). The residual bone material in group C (19.34 ± 8.03) was as much as one-half of that in group A (38.69 ± 7.90%) (P = 0.000). The negative control group B presented the highest amount of soft tissue within the bone defects. The least percentage of marrow space was found in the positive control group (13.23 ± 13.52). Our results depicted that the rate of resorption increased significantly after nanonization even though the nano-sized BCP failed to make a superior regeneration than the ordinary BCP.

Facial Nerve Injury and Other Complications Following Retromandibular Subparotid Approach for the Management of Condylar Fractures

PURPOSE

To estimate the prevalence and identify risk factors for facial nerve paralysis (FNP) and other postoperative complications after the use of the retromandibular subparotid approach (RMSA) for the treatment of condylar fractures.

MATERIALS AND METHODS

Radiologic and clinical data from all patients who underwent an RMSA from 2007 through 2015 at the University Hospital of Geneva (Geneva, Switzerland) were retrospectively reviewed. The primary and secondary outcome variables were, respectively, FNP and other complications (unesthetic scars, infection, nonunion, malocclusion, salivary fistula, Frey syndrome, and loosening or breaking of plates and screws). Predictor variables included age, gender, mechanism of injury, delay from injury to surgery, surgeon's experience, location of fracture, side and pattern of fracture, concomitant facial fractures, and status of healing. Univariable logistic regression statistics were computed.

RESULTS

Forty-eight subcondylar fractures in 43 consecutive patients were treated using the RMSA. Six fracture sites (12.5%) developed a temporary FNP that completely resolved within 4 months. Fractures at the neck level and with the comminution pattern were significant risk factors of postoperative FNP (P = .04 and P < .001, respectively; odds ratio = 82). Eight patients (18.6%) developed a slight transient malocclusion that was completely corrected within 3 to 4 weeks using guiding elastics and 1 patient (2.3%) had a wound dehiscence that resolved with a visible but thin and linear scar.

CONCLUSION

The present study showed that 1) the FNP rate after the RMSA to surgery for condylar fractures was similar to that reported after the transparotid variant; 2) the FNP was transient and completely resolved in all patients; 3) neck and comminuted condylar fractures were statistically associated with increased risk of developing a postoperative temporary FNP; and 4) the final outcome was favorable with no major complications in any of the patients.

Retraction force necessary to expose the mandibular neck in Risdon and high cervical anteroparotid transmasseteric approaches: an anatomic comparative study

PURPOSE

The purpose of this anatomic study was to compare the retraction force necessary to expose the mandibular neck in the Risdon and the high cervical anteroparotid transmasseteric (HAT) approaches.

METHODS

An anatomic study was performed on 18 formalin-embalmed cadavers. We performed a Risdon approach on the left side, and an HAT approach on the right side in all the cases. The subjects were placed in a normative frame and the force necessary to maintain a satisfactory exposure of the condyle was measured with a system of cables, pulleys, and mechanical dynamometer. The statistical comparison between the two sides was carried out using the Wilcoxon signed-rank test for paired series.

RESULTS

In all the cases, the region of interest was exposed as in the operating room. In the Risdon approach, the mean force was 32 Newtons (4-47). In the HAT approach, the mean force was 19 Newtons (4-33). The difference was statistically significant (p < 0.001). The age, gender, and duration of conservation had no influence on the retraction force.

CONCLUSION

In the HAT approach, the retraction of the soft tissues was significantly lower than in the Risdon approach. This study gave an additional explanation to the remarkable safety of the HAT approach. Our results were in favor of the generalization of this technique.

The Relationship of the Facial Nerve to the Condylar Process: A Cadaveric Study with Implications for Open Reduction Internal Fixation

Introduction. The mandibular condyle is the most common site of mandibular fracture. Surgical treatment of condylar fractures by open reduction and internal fixation (ORIF) demands direct visualization of the fracture. This project aimed to investigate the anatomic relationship of the tragus to the facial nerve and condylar process. Materials and Methods. Twelve fresh hemicadavers heads were used. An extended retromandibular/preauricular approach was utilized, with the incision being based parallel to the posterior edge of the ramus. Measurements were obtained from the tragus to the facial nerve and condylar process. Results. The temporozygomatic division of the facial nerve was encountered during each approach, crossing the mandible at the condylar neck. The mean tissue depth separating the facial nerve from the condylar neck was 5.5 mm (range: 3.5 mm–7 mm, SD 1.2 mm). The upper division of the facial nerve crossed the posterior border of the condylar process on average 2.31 cm (SD 0.10 cm) anterior to the tragus. Conclusions. This study suggests that the temporozygomatic division of the facial nerve will be encountered in most approaches to the condylar process. As visualization of the relationship of the facial nerve to condyle is often limited, recognition that, on average, 5.5 mm of tissue separates condylar process from nerve should help reduce the incidence of facial nerve injury during this procedure.

Surgical treatment of mandibular condyle fractures using the retromandibular anterior transparotid approach and a triangular-positioned double miniplate osteosynthesis technique: A clinical and radiological evaluation of 124 fractures

OBJECTIVE

Different modalities have been described regarding the treatment of mandibular condyle fractures. The most advantageous and safest one is still a topic of discussion. The present analysis describes the combination of a retromandibular, transparotideal approach combined to a triangular-positioned double-miniplate osteosynthesis, with a special regard for the patients' long term outcomes.

MATERIAL AND METHODS

Clinical data of 102 patients with 124 condyle fractures treated with the mentioned surgical procedure were evaluated. Functional parameters such as the maximal interincisal distance, deviations/deflections, facial nerve function, occlusion as well as complications regarding the parotid gland, osteosynthesis, and esthetics were evaluated 1 week, 2 weeks, 3 months, and 6 months postoperatively.

RESULTS

The mean maximal interincisal distance ranged from 38 mm after 1 week to 45 mm after 6 months. Deviations/deflections were seen in 22.5% of the cases 1 week postoperatively and decreased to 2% at 6 months postoperatively. A temporary facial palsy was diagnosed in 3.9% during the first follow-up, whereas no impairment was recorded after 3 or 6 months. At the same time, no patient had occlusional disturbances or complications regarding the parotid gland or the osteosynthesis 6 months postoperatively.

CONCLUSIONS

Direct fracture visualization and a stable three-dimensional fracture stabilization are the main advantages of the presented combination of a surgical approach and osteosynthesis technique. Additionally, the absence of long-term complications confirms the safety of the procedure. Therefore, it may be considered as a successful treatment option for mandibular condyle fractures.

Epidemiology and treatment outcome of surgically treated mandibular condyle fractures. A five years retrospective study

Surgical management of mandibular condyle fractures is still controversial. Although it provides better outcome than closed treatment questions still remain about the surgical approach and the osteosynthesis devices to be used. Between 2005 and 2010, we managed 168 mandibular condyle fractures with open treatment. Two surgical approaches were used in this study, a pre-auricular and a high submandibular approach (one or the other or as a combined approach). Internal fixation was performed using TCP(®) plates (Medartis, Basel, Switzerland) or with two lag screws (15 and 17 mm). Delta plates were used in 15 cases (8.9%). We report the epidemiology of these fractures and the outcomes of the surgical treatment. We assessed the complications related to the surgical procedure and those related to the osteosynthesis material. The facial nerve related complication rate was very low and the osteosynthesis materials used proved to be strong enough to realize a stable fixation. The two approaches used in this study appeared to be safe with good aesthetic results. Most of the surgical procedure failures occurred in high subcondylar fractures especially when bilateral.

Long-term results and complications after treatment of bilateral fractures of the mandibular condyle

The purpose of this study was to investigate the long-term results of conservative treatment of bilateral condylar fractures and to study the influence of possible functional impairment on intensity of pain and associated disability. We studied 71 patients (mean (SD) age 33 (14) years) with conservatively treated bilateral condylar fractures. Traffic crashes (n=42, 59%) and falls (n=20, 28%) were the main cause of the fractures. Forty-one patients (58%) were re-examined after about 90 months (mean 86, range 3-193). Five of the 41 (12%) had developed malocclusion, but did not experience any pain in the temporomandibular joint according to the Research Diagnostic Criteria for Temporomandibular Disorders. There was a significant negative relation between the presence of pain and the duration of follow up (p=0.02). Increasing age was significantly related to reduction in the intensity of pain (p=0.03). Of the remaining 30 patients who were not followed up, 2 had had bilateral sagittal split osteotomy and 1 a Le Fort I osteotomy. One patient had had orthodontic correction for a malocclusion. Including the five malocclusion patients, at least 9 of the total of 71 (13%) developed a malocclusion after conservative treatment. Functional impairment had no influence on the intensity of pain or pain-related disability in the patients with malocclusion after conservatively treated bilateral condylar fractures. This report may therefore be of value in the debate about whether open or closed treatment is better for bilateral mandibular condylar fractures.

Combined surgical approach retromandibular and intraoral to subcondylar mandibular fractures

BACKGROUND

Condylar and subcondylar fractures are very common and account for at least one third of all mandibular fractures. In literature, little agreement exists about the management of extracapsular condylar and subcondylar fractures in adults. Some studies provide better results of occlusion, masticatory function, mouth opening, and bone morphology with surgical treatment. Conversely, other studies report excellent results with conservative treatment avoiding complications such as facial nerve injury and unsightly scar.

METHODS

In this study, we report our experience of 25 condylar/subcondylar fractures. We report the case of a man with bilateral subcondylar fractures treated by a double surgical approach, intraoral and retromamdibular. Intraoral approach lets us dissect the masseter and disconnect the temporal muscle tendon, thus favoring further reduction of fracture stumps, whereas retromandibular approach favors a good operative field and the positioning of titanium microplate.

RESULTS

Postoperative monitoring reported good results of occlusion. Postoperative computed tomographic scans show the good reduction and positioning of titanium miniplate.

Comparison of approaches for the rigid fixation of sub-condylar fractures

AIM

The objective of this study was to compare the rate of complications encountered on using different incisions to access the fracture site for the open reduction and internal fixation of isolated subcondylar fractures. The parameters evaluated are: the occurrence of salivary fistula, infection, and injuries to the seventh facial nerve. An assessment of the surgical scar was also undertaken.

MATERIALS AND METHODS

20 patients who met the previous criteria and were willing to participate in the study were placed (five each) into the pre-auricular, submandibular, retromandibular transparotid or retromandibular transmassetric group based on the incision scar they selected after a description of the operation and being explained about the possible complications.

RESULTS AND CONCLUSION

Comparison of the complications could not ascertain the superiority of any approach over the other since the outcomes were not statistically significant. However, judging by operator and assistants' subjective assessment, the retromandibular approaches seem to provide a more direct visual field and an almost straight line access for the fixation of the fracture. The transmassetric approach seems to be a safer approach since the nerves encountered can be visualized and avoided.

Is failure of condylar neck osteosynthesis predictable based on orthopantomography?

BACKGROUND

Osteosynthesis failure rates of 11.3% with 1 miniplate, 6.7% with 2 miniplates, and 4.4% with a single Medartis condyle plate were reported in previous studies of our clinic. Current science is still focused on the osteosynthesis material. Besides clinical parameters, conventional radiographs are still the first choice to detect osteosynthesis failures. This study scrutinized several factors assessable in postoperative orthopantomographs which might elevate the risk of osteosynthesis failure.

STUDY DESIGN

A total of 136 patients (22 with osteosynthesis failure, 114 without) with 151 mandibular condyle fractures were included in this study. Eight parameters were assessed in postoperative orthopantomographs.

RESULTS

The best predictor of osteosynthesis failure was a simplified concept of ramus height. In cases of reduced or normal ramus height, the odds of osteosynthesis failure was significantly (P = .000001) reduced to a 10th. Isolated fractures were significantly more error prone (P = .0009).

CONCLUSIONS

Postoperative orthopantomographs depict factors which increase the risk of osteosynthesis failure.

Clinical indication for intraoperative 3D imaging during open reduction of fractures of the neck and head of the mandibular condyle

PURPOSE

This study aimed to evaluate the use of intraoperative cone-beam computed tomography (CBCT) in monitoring the results of repositioning and osteosynthesis of condylar process and head (capitulum) fractures of the mandible to see if CBCT is beneficial for these patients.

PATIENTS AND METHODS

Sixty patients (22 females and 38 males, age range 16-79 years, average 36.5 years) with condylar process and head fractures according to the classification of Spiessl and Schroll were treated during the study period. Thirty-four of the 60 patients received a CBCT scan immediately after surgical treatment under aseptic conditions.

RESULTS

In all 34 cases, intraoperative CBCT provided high-quality imaging of the condylar process in all three planes. In four patients (11.8%), unsatisfactory reposition or unexpected complications were detected which could immediately be corrected with a surgical revision.

CONCLUSION

Intraoperative use of CBCT enables optimization of the surgical outcome for fractures of the condylar process and head of the mandible, reduces postoperative complications, and spares patients from repeated intervention. In addition, intraoperative CBCT enables safer treatment with minimally invasive approaches.

Is the high submandibular transmasseteric approach to the mandibular condyle safe for the inferior buccal branch?

PURPOSE

There are basically 3 main approaches for extra-articular mandibular condyle fractures: low cervical, retromandibular and preauricular. These include a risk of facial palsy affecting the marginal mandibular branch. We use a high submandibular transmasseteric approach featuring masseter section 10-20 mm above the mandibular basilar edge. Our null hypothesis was that both the marginal mandibular and the inferior buccal branches are not more at risk than in other surgical approaches.

METHODS

This study was based on 20 parotidomasseteric dissections from 10 embalmed cadaveric heads. We used as reference the vertical line, passing through the mandibular angle, parallel to the preauricular line. We performed measurements of the marginal mandibular and inferior buccal branches' heights.

RESULTS

The inferior buccal branch had an average height of 16.8 mm and the highest standard deviation (7.2). Extremes were, respectively, 32 and 7 mm. The marginal mandibular branch had an average height of 3.2 mm with standard deviation equal to 3.0. Extremes were, respectively, 9 and -3 mm.

CONCLUSION

The high submandibular transmasseteric approach provides great exposure of facial nerve branches lying on the masseter muscle, if even encountered. Through masseteric incision performed between 10 and 20 mm above the basilar edge of the mandible, the marginal mandibular branch is safe from wound with an added safety margin of 4 mm. The surgeon using this approach is most likely to encounter the inferior buccal branch. It can then be avoided under visual control. This makes it a swift and safe approach to the mandibular condyle.