Abstract | | |
Nonunion post-mandibular fractures are relatively uncommon. They pose severe challenge in terms of treatment and quality of life. The cause for pseudo-union is multi-dimensional. Removal of the cause or treating the same is an absolute need to provide correct treatment. Successful correction of a case of pseudo-union of fractured mandible occurring after two previous treatment attempts is presented. The possible explanation for the pseudo-union as well as the precautions to be taken to prevent such occurrence is discussed.
Keywords: Fracture, graft, mandible, nonunion, pseudo-joint, rib graft
How to cite this article: Balaji S M, Balaji P. Post-traumatic pseudo joint formation at the angle of mandible - A case report. Indian J Dent Res 2020;31:791-3 |
How to cite this URL: Balaji S M, Balaji P. Post-traumatic pseudo joint formation at the angle of mandible - A case report. Indian J Dent Res [serial online] 2020 [cited 2022 Aug 8];31:791-3. Available from: https://www.ijdr.in/text.asp?2020/31/5/791/306468 |
Background | |  |
The aim and goal in treating mandibular fractures are to induce rapid healing through anatomic reduction and fixation, with minimal disability and complications. Though several techniques including maxillomandibular fixation with and without intraosseous wiring, external rigid fixation and rigid internal fixation have been identified,[1] if not approached or treated properly, substantial long-term risks exist for complications when treating mandible fractures. These could include persistent infection, malunion, delayed union, nonunion, disturbances of sensation and malocclusion.[2] Mandibular nonunions are classically defined as non-healing discontinuity in bone that continue to demonstrate mobility either 4 weeks after conservative management or 8 weeks after surgical treatment.[3] This uncommon unfavourable outcome has a reported incidence of 2.8 to 3.9% and often occur in body/angle of the mandible. Nonunion and union by fibrous tissues (pseudo-union) due to infection can lead to pain, trismus, malocclusion and inability to chew.[3],[4]
Residual infection, inadequate fracture stabilization/reduction, comminuted and devascularised bone, inadequate soft tissue coverage, improper antibiotic coverage and delayed treatment are suggested etiopathogenic mechanisms for pseudo-union. Risk factors include teeth in the line of fracture, complex or comminuted fracture, limited experience of surgeon and patient-related characteristics, such as edentulous mandible, tobacco use, alcohol abuse, immune deficiency, diabetes mellitus or patient non-compliance.[4] Treatment of such condition generally includes creation of healthy bony edges, bone grafting in critical sized defects, immobilization, rigid fixation to achieve stabilization and optimal healing. This may be done in one or more stages. Algorithms to this effect has been suggested.[1],[2],[3],[4]
The role of operating surgeon's experience and skill is a crucial factor while managing fractures.[5],[6] The intention of this manuscript is to describe the rehabilitation of a nonunion fracture caused by mismanagement twice earlier.
Case Report | |  |
A 34-year-old male patient reported with the complaint of swelling in the left lower jaw region with the lower lip on the affected side having loss of sensation. He gives a history of motor-road traffic accident 6 months earlier. He was diagnosed as having a left mandibular angle comminuted fracture and was surgically managed. In spite of the treatment, the swelling and the pain did not subside even after eight weeks. Subsequently, he was operated again. During this second surgery, previously placed plates and screws along with the impacted 3rd molar were removed and the reconstructive plate was placed. Again patient had no relief as the swelling in the region persisted and he was unable to chew.
On clinical examination, a single swelling was seen on the left mandible [Figure 1]a. The swelling was hard in consistency, warm and tender on palpation. Patient had demonstrable post-operative paraesthesia on left lower lip. Intraorally, he had anterior open bite, malocclusion, arch bars fixed on his upper and lower jaw, grade 3 mobility in left lower second molar, and extensive stains on all his teeth [Figure 1]b, [Figure 1]c. The present orthopantamogram demonstrated a critical sized defect along the left angle of mandible with reconstructive plate fixed from the ramus to the body of mandible [Figure 1]d. The three-dimensional computed tomography, taken after the second surgery, showed a discontinuity in left mandibular angle fracture, with left condyle pulled towards right side [Figure 2]a, [Figure 2]b, [Figure 2]c. Probably during the second surgery, bone fragments were removed creating a critical sized defect leading to malunion in that part of the mandible. A working diagnosis of nonunion was arrived at. Treatment plan was to remove the reconstructive plate, refixing occlusion and reconstruction of defective bone site with rib graft. | Figure 1: (a and b) Pre-operative view showing swelling in left mandible with paraesthesia of lower lip (left side). (c) Preoperative occlusal view showing anterior open bite. (d) Orthopantomogram demonstrated a critical sized defect along the left angle of mandible with reconstructive plate fixed from the ramus to the body of mandible
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 | Figure 2: (a-c) Three-dimensional computed tomography scan showing nonunion of left mandibular angle with left condyle pulled towards the right side
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Under general anaesthesia and standard preparation, nasotracheal intubation was done. Through a right infra-mammary incision, a rib graft was harvested [Figure 3]b. Positive pressure ventilation check for pleural perforation was performed. Donor site closure was achieved in layers by using 2.0 vicryl, 3.0 vicryl and 4.0 ethilon. Next, through an intraoral approach, existing lower arch bar were removed and extraction of periodontally compromised second molar was performed [Figure 3]a, [Figure 3]b, [Figure 3]c. A retromolar incision was placed at the left angle of the mandible, mucoperiosteal flap elevated and the unstable defective bony site was explored. Previously placed reconstructive plate and screws were removed and areas of fibrous union in upper border of left ramus and body of mandible were separated. Eyelets were placed in lower arch. Mandible was brought into occlusion and intermaxillary fixation was done in proper occlusion. Abnormally united left ramus along with fibrous tissue in relation to third molar was released, placed in posterior most position. With the help of occlusion, proper position of left ramus and the body of mandible was achieved using reconstructive plate. The defective site was large due to removal of the third molar and measured approximately 3 cm in height and 2.5 cm in width. Bony defect was augmented using rib graft, and fixed with titanium plates and screws. Upper arch bar and lower eyelets were removed. Closure was achieved using 3.0 vicryl. Patient was extubated uneventfully. Appropriate antibiotics, non-steroidal anti-inflammatory drugs and post-operative care instructions were provided. Patient was asked to refrain from smoking or use of tobacco in any form, as he was a smoker. Patient healed well and post-surgical orthopantomogram at 1 year showed perfect healing and facial symmetry being achieved. Patient is under periodic review and doing well. Post-surgically, the paraesthesia in the lower lip resolved substantially after 8 weeks [Figure 4]a, [Figure 4]b, [Figure 4]c, [Figure 4]d. | Figure 3: (a) previously placed reconstructive plate and screws removed. (b) Ribgraft harvested from 7th intercostal rib. (c) Left mandibular angle defect reconstructed with rib graft and reconstruction plate
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 | Figure 4: (a-d) Post-surgical view and orthopantomogram at 1 year showing perfect healing and facial symmetry
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Discussion | |  |
The cause of mal-union, nonunion and pseudo-union in body-angle complex of mandible widely varies. There has been an algorithm suggested in literature to decide on the course of treatment. All such suggestions assume that the operating surgeon's skill, experience and expertise to be equal. However, the wide variations in the skill, knowledge and experience could pose a serious risk for patients. Besides the health and psychological suffering, such cases also pose huge financial implications.[2],[5],[6],[7]
In the present context, the patient is young, with no systemic complications or diseases, smoker and was maintaining adequate oral hygiene. Apart from involvement of a tooth in line of fracture[7] and smoking, there were no risk factors for fracture healing. Smoking influences oral healing.[8] The patient's compliance to medical advice was fairly adequate in our present experience. The temporary cessation of tobacco use in the postoperative period could have contributed to the successful outcome.[8]
The presence of abnormal healing process indicates that during the second corrective surgery, the edges of bones were not adequately approximated. The failures in past surgical treatment would lie at two points. One would be less than optimal surgical planning and treatment delivery (improper plate fixation) and the other would be preserving the tooth in line of fracture. In present context, both could have contributed to the abnormal healing. The failure to identify the same in the second surgery is a cause of concern. Neglect of same has led to persistent infection and swelling. Teeth in lines of fractures particularly posterior molars are known to lead to long-term complications and influence the healing. However, understanding the type/nature of fracture and degree of involvement of tooth with the fracture line could help to preserve or extract the concerned tooth. This decision is highly customized one and has to account several factors.[5],[8]
The skill, knowledge and experience of the operator in arriving at a diagnosis and surgical treatment decision are as important as estimation of other biological factors.[9] Predicting biological response of bone healing in advance is challenging as it involves a host of factors including genes, signalling molecules and a conducive environment. However, observing for “red flags” and challenges during formulation of the customized treatment algorithm requires certain expertise and experiment. In absence of this, unforeseen challenges such as persistent swelling due to nonunion and mal-union could occur.
Conclusion | |  |
A rare case of nonhealing pseudojoint formation due to fracture was successfully treated by careful consideration of local and systemic factor. Regaining facial symmetry, ability to painlessly chew food and engaging in active social life stands testimony to the success of the third surgery. Surgeons should look for the “red flags” during examination and while formulating customized treatment algorithm rather than blindly following advocated protocols.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
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4. | Ostrander BT, Wang HD, Cusano A, Manson PN, Nam AJ, Dorafshar AH. Contemporary management of mandibular fracture nonunion- A retrospective review and treatment algorithm. J Oral Maxillofac Surg 2018;76:1479-93. |
5. | Luz JG, Moraes RB, D'Ávila RP, Yamamoto MK. Factors contributing to the surgical retreatment of mandibular fractures. Braz Oral Res 2013;27:258-65. |
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7. | Balaji P, Balaji SM. Fate of third molar in line of mandibular angle fracture-Retrospective study. Indian J Dent Res 2015;26:262-6.  [ PUBMED] [Full text] |
8. | Balaji SM. Tobacco smoking and surgical healing of oral tissues: A review. Indian J Dent Res 2008;19:344-8.  [ PUBMED] [Full text] |
9. | Emara KM, Diab RA, Emara AK. Recent biological trends in management of fracture non-union. World J Orthop 2015;6:623-8. |

Correspondence Address: Dr. S M Balaji Director and Consultant, Oral and Maxillofacial Surgeon, Balaji Dental and Craniofacial Hospital, 30, KB Dasan Road, Teynampet, Chennai – 600 018 India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/ijdr.IJDR_949_20

[Figure 1], [Figure 2], [Figure 3], [Figure 4] |