Variations in the Position of Mandibular Foramen in Temporomandibular Ankylosis Patients.

Aim: To evaluate the variation in the position of the mandibular foramen and mandibular canal in patients with and without temporomandibular joint ankylosis. Materials and Methods: 100 temporomandibular joints were evaluated of which 50 joints were ankylosed joints (Group A) and the rest 50 were normal joints (Group B) without ankylosis. These groups were further divided into those with growing potential (less than 18 years) and those without growing potential (above 18 years). The position of the mandibular foramen was measured from its center to the glenoid fossa, sigmoid notch, coronoid notch, gonion and posterior border on CBCT scans. The position of the mandibular canal was measured from the outer aspect of the canal to the lower border of the mandible, buccal and lingual cortical plates and the alveolus in the region of the 1st, 2nd and 3rd molars. Results: The mean distance of the foramen from the base of the skull in Group A was 19.01 mm while the same for Group B was 31.26 mm. The mandibular foramen was found to be closer to the occlusal plane (5.43 mm) in Group A as compared to the mean distance of 6.21 mm reported in Group B. There was no significant difference in the position of the foramen from the posterior border, gonion and sigmoid notch between the groups. The mental foramen was seen more commonly posterior to the 2nd premolar and closer to the first molar region in Group A while in Group B it was seen anterior or near the 2nd premolar. In Group A, the mean distance of the canal to the buccal cortical plate in the 1st and 2nd molar regions was 3.65 mm and 5.76 mm, respectively, while in Group B it was 6.09 mm and 6.59 mm. The canal was further away from the lower border in ankylosis cases (8.79 mm) than the control group (7.41 mm). On comparing the unaffected side in unilateral cases with the normal mandible, the canal and the foramen location were similar to that of a normal mandible with the values in the lower range that is usually seen in normal mandibles. Conclusion: Ankylosis of the mandible is a debilitating condition especially when it develops in an individual prior completion of growth as it can affect the mandibular anatomy. Understanding the variations that accompany a deranged mandible can assist the surgeon in planning of surgical procedures in a manner that limits the possible complications resulting from surgery.

Intravenous catheter flanges as an external nasal stent: a novel technique.

External nasal splints are commonly used for immobilization following nasal fracture reduction or rhinoplasty procedures. The literature documents the use of various materials like thermoplastic materials, aluminum, Orthoplast, fiberglass, plaster of Paris, and polyvinyl siloxane. These materials are bulky, time-consuming, expensive, and cumbersome to use, and have been associated with complications including contact dermatitis and epidermolysis. Furthermore, they cannot be retained if the situation warrants prolonged stabilization and immobilization. We introduce a new technique using readily available scalp vein catheter flanges as an external nasal stent. The technique is easy to master, inexpensive, and limits edema and ecchymosis, while stabilizing the reconstructed nasal skeleton in position during the healing period.

Patient Specific Alloplastic Implant Reconstruction of Mandibular Defects-Safe Practice Recommendations and Guidelines.

Mandibular continuity defects are commonly seen after tumor resection, osteomyelitis or maxillofacial trauma. Three-dimensional reconstruction of these mandibular segmental defects is critical for proper mandibular functioning and esthetics. Various methods used to reconstruct such defects include bridging reconstruction plates, modular endoprosthesis, non-vascularized and vascularized bone grafting with stock reconstruction plate or patient specific implants (PSI) and tissue engineering bone transfer. But in the recent years, literature documents use of PSI only alloplastic reconstruction as an alternate to microvascular bone flap reconstruction. Representative cases enumerate current practice of 'patient specific implant only' mandibular reconstruction and its pitfalls. This article discusses current status of literature on PSI's, choice of indications for 'PSI only' mandibular reconstruction and also proposes guidelines for safe practice of patient specific implant reconstruction of mandible.

Controlling and Stabilising Mandible During Reconstruction: Significance and Techniques.

Objective: Stable and accurate positioning of condyle in the glenoid fossa is necessary for maintaining occlusion, facial symmetry and normal function of the temporomandibular joint following segmental resection of mandible. In non-reconstructed mandibular segments or those with fractured reconstruction plates the bony defect gets altered due to contraction or inadvertent muscular pull. This paper describes various techniques used to control dentate and edentate segments of the mandible during reconstruction following an ablative procedure. Discussion: Secondary mandibular reconstruction has always been a tedious task for the surgeons. Several techniques have been described in literature ranging the use of external fixators, gunning splints and dentures for stabilising mandibular segments. Use of a pre-bent and adapted reconstruction plate is a common practice but may not be feasible in malignancies, benign tumours causing expansion and secondary reconstruction. The current advances in virtual surgical planning allows mandibular reconstruction to be performed in a simpler yet predictable manner. Conclusion: The paper describes techniques ranging from twin K-wire placement to occlusal wafers, 3D printed splints and patient specific implants to enable accurate positioning of the segments and achieve pre-operative form. Advances in virtual surgical planning will continue to allow this field to evolve and to improve the quality of life of the patients.