Mandible Fractures
Jeffrey R. Marcus, Detlev Erdmann, Eduardo D. Rodriguez in Essentials of CRANIOMAXILLOFACIAL TRAUMA, 2014
On the buccal surface, a faint median ridge at the midline of the mandible marks the symphysis (Fig. 16-2). The symphysis divides near the inferior border, creating a triangle enclosing the mental protuberance. The base of this triangle is depressed at the center and raised at the ends, forming bilateral mental tubercles. The oblique line runs from each mental tubercle in a posterior and superior path, aiming just posterior to the third molar, where it blends into the anterior border of the ramus. The triangularis muscle attaches to the anterior half of the oblique line, with the quadratus labii inferioris muscle attachment superior and the platysma attachment inferior. The mental foramen is located below the second premolar approximately halfway between the superior and inferior borders; it allows passage of the mental neurovascular bundle. There is an incisive fossa on either side of the symphysis just below the lower incisors that serves as the origin for the mentalis and as the partial origin for the orbicularis oris muscle. On the lingual surface, the genloglossi muscles originate at the inferior border of the symphysis from bilateral mental spines, with a second pair of spines, or ridge, inferior to these, marking the origin of the geniohyoid muscles. Immediately below this on either side is the anterior margin of the mylohyoid line, which, like the oblique line, runs in a posterior and superior fashion toward the inferior margin of the third molar. This line is the origin for the mylohyoideus muscle.
Cranial Neuropathies I, V, and VII–XII
Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw in Hankey's Clinical Neurology, 2020
Numb chin syndrome is usually seen in patients with systemic malignancy (lymphoreticular neoplasms, breast, lung, prostate, colon, and thyroid cancer), but may be seen with noncancerous etiologies including dental procedures, dental infection, connective tissue disease, or trauma. The mental nerve is a branch of the inferior alveolar nerve, which arises from V3. It exits through the mental foramen and supplies sensation to the chin and lower lip. The nerve may be compressed by a metastasis to bone at the mental foramen or along its course; it may also be infiltrated by tumor. Sensory loss extending beyond the chin and lower lip may indicate a more proximal V3 lesion or leptomeningeal involvement. Evaluation should include MRI of the brain with contrast with special attention to the trigeminal nerve and its branches, dedicated MRI of the mandible if brain MRI is nonrevealing, and CSF examination.15,28
Regional Anesthesia
Marwali Harahap, Adel R. Abadir in Anesthesia and Analgesia in Dermatologic Surgery, 2019
Nerve block technique(s) (Fig. 1): Identify the mental foramen. This is located in the midpupillary line midway between the alveolar margin and the inferior border of the mandible.Inject 2 to 3 mL of 1–2% lidocaine (choose concentration after considering volume and dosing limitations) in a fan-shaped pattern circumferentially around the foramen. This will block the mental nerve. Injection depth should be submuscular near the bony surface.
Oral mucosa grafting in periorbital reconstruction
Published in Orbit, 2018
Sensory innervation is delivered by the mental nerve, a terminal branch of the inferior alveolar nerve arising from the mandibular division of the trigeminal nerve (CNV3). The mental nerve leaves the mandible via the mental foramen located between the first and second premolar teeth.74,75 The harvesting surgeon must be aware of the risk of lower lip paraesthesia due to the close proximity of the labial mucosa graft harvest site to the mental foramen. The initial incision should be placed medial to the middle of the canines to avoid mental nerve injury. In addition, the surgeon should keep at least a 1–1.5 cm margin away from the lip vermillion to prevent lip contracture and inversion from post-operative scarring.79 Moreover, injury to the orbicularis oris muscle may limit mobility of the lips and impair smiling. Damage to the masticatory mucosa may predispose to periodontal defects if the labial mucosal graft is harvested outside the vestibule vertically near the teeth.74
The effect of shock waves on mineralization and regeneration of distraction zone in osteoporotic rabbits
Published in Annals of Medicine, 2023
Enes Özkan, Erman Şenel, Mehmet Cihan Bereket, Mehmet Emin Önger
The test animals were not fed the day before the procedure. The subjects to be operated on were randomly selected without knowing which group they belonged to. For general anaesthesia, 50 mg/kg ketamine HCL and 8 mg/kg xylazine HCL were administered intramuscularly to all animals. Local anaesthesia with 0.5 ml of articaine containing 1:200000 epinephrine was applied to the surgical area. After shaving the left mandible of the rabbits and providing aseptic conditions with povidone iodine, a 3 cm long linear incision was made at the inferior border of the left mandible. A full-thickness flap was elevated. The osteotomy line was performed along the premolar tooth and the mental foramen. Before the osteotomy was performed, a custom-made titanium distractor that could be lengthened by 10 mm was positioned parallel to the lower border of the mandible with six titanium mini-screws (Figure 3). Then, the bone osteotomy was performed with the help of fissure burs and osteotomes under sterile saline irrigation and taking care to avoid mental nerve damage. The incision area was closed in layers with 4/0 polyglactin 910 sutures. After the latency period, the distraction protocol was applied for ten days with a distraction rate of 0.35 mm/12 h.
Detection and characterization of the accessory mental foramen using cone-beam computed tomography
Published in Acta Odontologica Scandinavica, 2018
Yihan Li, Xiangwen Yang, Bichu Zhang, Bin Wei, Yao Gong
The mental foramen (MF) is a single opening on each side of the mandible through which the mental nerve and vessels emerge to provide sensory innervation and blood supply. However, human mandibles presenting additional foramina are not a rare finding and reported to complicate certain dental procedures [1,2]. Especially, the additional buccal foramen showing continuity with the mandibular canal is referred to as the accessory mental foramen (AMF) and deserves the full attention of clinicians and surgeons for its neurovascular contents [3–7].
Related Knowledge Centers
- Foramen
- Inferior Alveolar Nerve
- Mandible
- Mandibular Foramen
- Mandibular Canal
- Lip
- Depressor Labii Inferioris Muscle
- Mental Nerve
- Inferior Alveolar Artery
- Toothlessness