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Oral and Maxillofacial Surgery

  • Sentinel node: First node receiving lymphatic drainage from tumor.
  • Drooling management:
    • Bilateral submandibular duct relocation to posterior tonsillar pillar (preferred).
    • Bilateral parotid duct relocation.
  • Sublingual salivary gland tumors: <1% of salivary neoplasms; >80% malignant (adenoid cystic/mucoepidermoid carcinoma).
  • FNAC for salivary gland pathology: Specificity: 88 – 99%; Sensitivity: 71 – 93%.
  • Sistrunk operation: Thyroglossal duct cyst excision → includes hyoid bone & retrohyoid tract.

  • Poorly differentiated tumors: Highest malignancy
  • Argon – beam coagulation: Controls bleeding <3 mm vessels
  • Cryosurgery: Liquid nitrogen ( – 196°C), CO₂/N₂O ( – 200 to – 900°C)
  • PET imaging: Uses Fluorodeoxyglucose (FDG) → detects ↑ glucose uptake in malignancy
  • Organ of Chievitz: Juxtaoral organ near internal pterygoid; may mimic perineural invasion

  • Continuous locked suture: Maintains tension
  • Mattress suture: Entry/exit in same flap; for tension areas
  • Subcuticular suture: No knots; for exposed areas
  • Suture increases infection risk: 10,000×
  • Nylon: Has memory property
  • Chromic catgut: Stronger than plain; delayed resorption
  • Common needle: 3/8 circle, reverse cutting, 26 mm, 3.0 braided
  • Preservative for gut sutures: Isopropyl alcohol

Ridge Augmentation Procedures

Ridge augmentation procedures are surgical techniques used to increase the volume and density of the alveolar ridge in the maxilla and mandible. These procedures are often necessary to prepare the site for dental implants, especially in cases where there has been significant bone loss due to factors such as tooth extraction, periodontal disease, or trauma. Ridge augmentation can also be performed in conjunction with orthognathic surgery to enhance the overall facial structure and support dental rehabilitation.

Indications for Ridge Augmentation

  • Insufficient Bone Volume: To provide adequate support for dental implants.
  • Bone Resorption: Following tooth extraction or due to periodontal disease.
  • Facial Aesthetics: To improve the contour of the jaw and facial profile.
  • Orthognathic Surgery: To enhance the results of jaw repositioning procedures.

Types of Graft Materials Used

Ridge augmentation can be performed using various graft materials, which can be classified into the following categories:

  1. Autografts:

    • Bone harvested from the patient’s own body, typically from intraoral sites (e.g., chin, ramus) or extraoral sites (e.g., iliac crest).
    • Advantages: High biocompatibility, osteogenic potential, and lower risk of rejection or infection.
    • Disadvantages: Additional surgical site, potential for increased morbidity, and limited availability.
  2. Allografts:

    • Bone grafts obtained from a human donor (cadaveric bone) that have been processed and sterilized.
    • Advantages: No additional surgical site required, readily available, and can provide a scaffold for new bone growth.
    • Disadvantages: Risk of disease transmission and potential for immune response.
  3. Xenografts:

    •  Bone grafts derived from a different species, commonly bovine (cow) bone.
    • Advantages: Biocompatible and provides a scaffold for bone regeneration.
    • Disadvantages: Potential for immune response and slower resorption compared to autografts.
  4. Alloplasts:

    •  Synthetic materials used for bone augmentation, such as hydroxyapatite, calcium phosphate, or bioactive glass.
    • Advantages: No risk of disease transmission, customizable, and can be designed to promote bone growth.
    • Disadvantages: May not integrate as well as natural bone and can have variable resorption rates.

Surgical Techniques

  1. Bone Grafting:

    • The selected graft material is placed in the deficient area of the ridge to promote new bone formation. This can be done using various techniques, including:
      • Onlay Grafting: Graft material is placed on top of the existing ridge.
      • Inlay Grafting: Graft material is placed within the ridge.
  2. Guided Bone Regeneration (GBR):

    • A barrier membrane is placed over the graft material to prevent soft tissue infiltration and promote bone healing. This technique is often used in conjunction with grafting.
  3. Sinus Lift:

    • In the maxilla, a sinus lift procedure may be performed to augment the bone in the posterior maxilla by elevating the sinus membrane and placing graft material.
  4. Combination with Orthognathic Surgery:

    • Ridge augmentation can be performed simultaneously with orthognathic surgery to correct skeletal discrepancies and enhance the overall facial structure.

Vestibuloplasty

Vestibuloplasty is a surgical procedure aimed at deepening the vestibule of the oral cavity, which is the space between the gums and the inner lining of the lips and cheeks. This procedure is particularly important in prosthodontics and oral surgery, as it can enhance the retention and stability of dentures by increasing the available denture-bearing area.

Types of Vestibuloplasty

  1. Vestibuloplasty (Sulcoplasty or Sulcus Deepening Procedure):

    • This procedure involves deepening the vestibule without the addition of bone. It is primarily focused on modifying the soft tissue to create a more favorable environment for denture placement.
    • Indications:
      • Patients with shallow vestibules that may compromise denture retention.
      • Patients requiring improved aesthetics and function of their prostheses.
    • Technique:
      • The procedure typically involves the excision of the mucosa and submucosal tissue to create a deeper vestibule.
      • The soft tissue is then repositioned to allow for a deeper sulcus, enhancing the area available for denture support.
  2. Labial Vestibular Procedure (Transpositional Flap Vestibuloplasty or Lip Switch Procedure):

    • This specific type of vestibuloplasty involves the transposition of soft tissue from the inner aspect of the lip to a more favorable position on the alveolar bone.
    • Indications:
      • Patients with inadequate vestibular depth who require additional soft tissue coverage for denture support.
      • Cases where the labial vestibule is shallow, affecting the retention of dentures.
    • Technique:
      • A flap is created from the inner lip, which is then mobilized and repositioned to cover the alveolar ridge.
      • This procedure increases the denture-bearing area by utilizing the soft tissue from the lip, thereby enhancing the retention and stability of the denture.
      • The flap is sutured into place, and the healing process allows for the integration of the new tissue position.

Benefits of Vestibuloplasty

  • Increased Denture Retention: By deepening the vestibule and increasing the denture-bearing area, patients often experience improved retention and stability of their dentures.
  • Enhanced Aesthetics: The procedure can improve the overall appearance of the oral cavity, contributing to better facial aesthetics.
  • Improved Function: Patients may find it easier to eat and speak with well-retained dentures, leading to improved quality of life.

Considerations and Postoperative Care

  • Healing Time: Patients should be informed about the expected healing time and the importance of following postoperative care instructions to ensure proper healing.
  • Follow-Up: Regular follow-up appointments may be necessary to monitor healing and assess the need for any adjustments to the dentures.
  • Potential Complications: As with any surgical procedure, there are risks involved, including infection, bleeding, and inadequate healing. Proper surgical technique and postoperative care can help mitigate these risks.

Microvascular Trigeminal Decompression (The Jannetta Procedure)

Microvascular decompression (MVD), commonly known as the Jannetta procedure, is a surgical intervention designed to relieve the symptoms of classic trigeminal neuralgia by addressing the underlying vascular compression of the trigeminal nerve. This procedure is particularly effective for patients who have not responded to medical management or who experience significant side effects from medications.

Overview of the Procedure

  1. Indication:

    • MVD is indicated for patients with classic trigeminal neuralgia, characterized by recurrent episodes of severe facial pain, often triggered by light touch or specific activities.
  2. Anesthesia:

    • The procedure is performed under general anesthesia to ensure the patient is completely unconscious and pain-free during the surgery.
  3. Surgical Approach:

    • The surgery is conducted using an intraoperative microscope for enhanced visualization of the delicate structures involved.
    • The arachnoid membrane surrounding the trigeminal nerve is carefully opened to access the nerve.
  4. Exploration:

    • The trigeminal nerve is explored from its entry point at the brainstem to the entrance of Meckel’s cave, where the trigeminal ganglion (Gasserian ganglion) is located.
  5. Microdissection:

    • Under microscopic and endoscopic visualization, the surgeon performs microdissection to identify and mobilize any arteries or veins that are compressing the trigeminal nerve.
    • The most common offending vessel is a branch of the superior cerebellar artery, but venous compression or a combination of arterial and venous compression may also be present.
  6. Decompression:

    • Once the offending vessels are identified, they are decompressed. This may involve:
      • Cauterization and division of veins that are compressing the nerve.
      • Placement of Teflon sponges between the dissected blood vessels and the trigeminal nerve to prevent further vascular compression.

Outcomes and Efficacy

  • Immediate Pain Relief:

    • Most patients experience immediate relief from facial pain following the decompression of the offending vessels.
    • Reports indicate rates of immediate pain relief as high as 90% to 98% after the procedure.
  • Long-Term Relief:

    • Many patients enjoy long-term relief from trigeminal neuralgia symptoms, although some may experience recurrence of pain over time.
  • Complications:

    • As with any surgical procedure, there are potential risks and complications, including infection, cerebrospinal fluid leaks, and neurological deficits. However, MVD is generally considered safe and effective.

Fixation of Condylar Fractures

Condylar fractures of the mandible can be challenging to manage due to their location and the functional demands placed on the condylar region. Various fixation techniques have been developed to achieve stable fixation and promote healing. Below is an overview of the different methods of fixation for condylar fractures, including their advantages, disadvantages, and indications.

1. Miniplate Osteosynthesis

  • Overview:

    • Miniplate osteosynthesis involves the use of condylar plates and screw systems designed to withstand biochemical forces, minimizing micromotion at the fracture site.
  • Primary Bone Healing:

    • Under optimal conditions of stability and fracture reduction, primary bone healing can occur, allowing new bone to form along the fracture surface without the formation of fibrous tissue.
  • Plate Placement:

    • High condylar fractures may accommodate only one plate with two screws above and below the fracture line, parallel to the posterior border, providing adequate stability in most cases.
    • For low condylar fractures, two plates may be required. The posterior plate should parallel the posterior ascending ramus, while the anterior plate can be angulated across the fracture line.
  • Mechanical Advantage:

    • The use of two miniplates at the anterior and posterior borders of the condylar neck restores tension and compression trajectories, neutralizing functional stresses in the condylar neck.
  • Research Findings:

    • Studies have shown that the double mini plate method is the only system able to withstand normal loading forces in cadaver mandibles.

2. Dynamic Compression Plating

  • Overview:

    • Dynamic compression plating is generally not recommended for condylar fractures due to the oblique nature of the fractures, which can lead to overlap of fragment ends and loss of ramus height.
  • Current Practice:

    • The consensus is that treatment is adequate with miniplates placed in a neutral mode, avoiding the complications associated with dynamic compression plating.

3. Lag Screw Osteosynthesis

  • Overview:

    • First described for condylar fractures by Wackerbauer in 1962, lag screws provide a biomechanically advantageous method of fixation.
  • Mechanism:

    • A true lag screw has threads only on the distal end, allowing for compression when tightened against the near cortex. This central placement of the screw enhances stability.
  • Advantages:

    • Rapid application of rigid fixation and close approximation of fractured parts due to significant compression generated.
    • Less traumatic than miniplates, as there is no need to open the joint capsule.
  • Disadvantages:

    • Risk of lateralization and rotation of the condylar head if the screw is not placed centrally.
    • Requires a steep learning curve for proper application.
  • Contraindications:

    • Not suitable for cases with loss of bone in the fracture gap or comminution that could lead to displacement when compression is applied.
  • Popular Options:

    • The Eckelt screw is one of the most widely used lag screws in current practice.

4. Pin Fixation

  • Overview:

    • Pin fixation involves the use of 1.3 mm Kirschner wires (K-wires) placed into the condyle under direct vision.
  • Technique:

    • This method requires an open approach to the condylar head and traction applied to the lower border of the mandible. A minimum of three convergent K-wires is typically needed to ensure stability.

5. Resorbable Pins and Plates

  • Overview:

    • Resorbable fixation devices may take more than two years to fully resorb. Materials used include self-reinforced poly-L-lactide screws (SR-PLLA), polyglycolide pins, and absorbable alpha-hydroxy polyesters.
  • Indications:

    • These materials are particularly useful in pediatric patients or in situations where permanent hardware may not be desirable.

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