Transoral Lithotomy: Procedure for Submandibular Duct Stone Removal

Transoral lithotomy is a surgical technique used to remove stones (calculi) from the submandibular duct (Wharton's duct). This procedure is typically performed under local anesthesia and is effective for addressing sialolithiasis (the presence of stones in the salivary glands).

Procedure

1. Preoperative Preparation:

   • Radiographic Assessment: The exact location of the stone is determined using imaging studies, such as X-rays or ultrasound, to guide the surgical approach.
   • Local Anesthesia: The procedure is performed under local anesthesia to minimize discomfort for the patient.

2. Surgical Technique:

   • Suture Placement: A suture is placed behind the stone to prevent it from moving backward during the procedure, facilitating easier access.
   • Incision: An incision is made in the mucosa of the floor of the mouth, parallel to the duct. Care is taken to avoid injury to surrounding structures, including:
     • Lingual Nerve: Responsible for sensory innervation to the tongue.
     • Submandibular Gland: The gland itself should be preserved to maintain salivary function.

3. Blunt Dissection:

   • After making the incision, blunt dissection is performed to carefully displace the surrounding tissue and expose the duct.

4. Identifying the Duct:

   • The submandibular duct is located, and the segment of the duct that contains the stone is identified.

5. Stone Removal:

   • A longitudinal incision is made over the stone within the duct. The stone is then extracted using small forceps. Care is taken to ensure complete removal to prevent recurrence.

6. Postoperative Considerations:

   • After the stone is removed, the incision may be closed with sutures, and the area is monitored for any signs of complications.

Complications

• Bacterial Sialadenitis: If there is a secondary infection following the procedure, it can lead to bacterial sialadenitis, which is an inflammation of the salivary gland due to infection. Symptoms may include pain, swelling, and purulent discharge from the duct.

Champy Technique of Fracture Stabilization

The Champy technique, developed by Champy et al. in the mid-1970s, is a method of fracture stabilization that utilizes non-compression monocortical miniplates applied as tension bands. This technique is particularly relevant in the context of mandibular fractures and is based on biomechanical principles that optimize the stability and healing of the bone.

Key Principles of the Champy Technique

1. Biomechanical Considerations:

   • Tensile and Compressive Stresses: Biomechanical studies have shown that tensile stresses occur in the upper border of the mandible, while compressive stresses are found in the lower border. This understanding is crucial for the placement of plates.
   • Bending and Torsional Forces: The forces acting on the mandible primarily produce bending movements. In the symphysis and parasymphysis regions, torsional forces are more significant than bending moments.

2. Ideal Osteosynthesis Line:

   • Champy et al. established the "ideal osteosynthesis line" at the base of the alveolar process. This line is critical for the effective placement of plates to ensure stability during the healing process.
   • Plate Placement:
     • Anterior Region: In the area between the mental foramina, a subapical plate is placed, and an additional plate is positioned near the lower border of the mandible to counteract torsional forces.
     • Posterior Region: Behind the mental foramen, the plate is applied just below the dental roots and above the inferior alveolar nerve.
     • Angle of Mandible: The plate is placed on the broad surface of the external oblique ridge.

3. Tension Band Principle:

   • The use of miniplates as tension bands allows for the distribution of forces across the fracture site, enhancing stability and promoting healing.

Treatment Steps

1. Reduction:

   • The first step in fracture treatment is the accurate reduction of the fracture fragments to restore normal anatomy.

2. Stabilization:

   • Following reduction, stabilization is achieved using the Champy technique, which involves the application of miniplates in accordance with the biomechanical principles outlined above.

3. Maxillomandibular Fixation (MMF):

   • MMF is often used as a standard method for both reduction and stabilization, particularly in cases where additional support is needed.

4. External Fixation:

   • In cases of atrophic edentulous mandibular fractures, extensive soft tissue injuries, severe communication, or infected fractures, external fixation may be considered.

Classification of Internal Fixation Techniques

• Absolute Stability:

  • Rigid internal fixation methods, such as compression plates, lag screws, and the tension band principle, fall under this category. These techniques provide strong stabilization but may compromise blood supply to the bone.

• Relative Stability:

  • Techniques such as bridging, biologic (flexible) fixation, and the Champy technique are classified as relative stability methods. These techniques allow for some movement at the fracture site, which can promote healing by maintaining blood supply to the cortical bone.

Biologic Fixation

• New Paradigm:
  • Biologic fixation represents a shift in fracture treatment philosophy, emphasizing that absolute stability is not always beneficial. Allowing for some movement at the fracture site can enhance blood supply and promote healing.
• Improved Blood Supply:
  • Not pressing the plate against the bone helps maintain blood supply to the cortical bone and prevents the formation of early temporary porosity, which can be detrimental to healing.

Glasgow Coma Scale (GCS): Best Verbal Response

The Glasgow Coma Scale (GCS) is a clinical scale used to assess a patient's level of consciousness and neurological function, particularly after a head injury. It evaluates three aspects: eye opening, verbal response, and motor response. The best verbal response (V) is one of the components of the GCS and is scored as follows:

Best Verbal Response (V)

• 5 - Appropriate and Oriented:

  • The patient is fully awake and can respond appropriately to questions, demonstrating awareness of their surroundings, time, and identity.

• 4 - Confused Conversation:

  • The patient is able to speak but is confused and disoriented. They may answer questions but with some level of confusion or incorrect information.

• 3 - Inappropriate Words:

  • The patient uses words but they are inappropriate or irrelevant to the context. The responses do not make sense in relation to the questions asked.

• 2 - Incomprehensible Sounds:

  • The patient makes sounds that are not recognizable as words. This may include moaning or groaning but does not involve coherent speech.

• 1 - No Sounds:

  • The patient does not make any verbal sounds or responses.

Punch Biopsy Technique

A punch biopsy is a medical procedure used to obtain a small cylindrical sample of tissue from a lesion for diagnostic purposes. This technique is particularly useful for mucosal lesions located in areas that are difficult to access with conventional biopsy methods. Below is an overview of the punch biopsy technique, its applications, advantages, and potential limitations.

Punch Biopsy

• Procedure:

  • A punch biopsy involves the use of a specialized instrument called a punch (a circular blade) that is used to remove a small, cylindrical section of tissue from the lesion.
  • The punch is typically available in various diameters (commonly ranging from 2 mm to 8 mm) depending on the size of the lesion and the amount of tissue needed for analysis.
  • The procedure is usually performed under local anesthesia to minimize discomfort for the patient.

• Technique:

  1. Preparation: The area around the lesion is cleaned and sterilized.
  2. Anesthesia: Local anesthetic is administered to numb the area.
  3. Punching: The punch is pressed down onto the lesion, and a twisting motion is applied to cut through the skin or mucosa, obtaining a tissue sample.
  4. Specimen Collection: The cylindrical tissue sample is then removed, and any bleeding is controlled.
  5. Closure: The site may be closed with sutures or left to heal by secondary intention, depending on the size of the biopsy and the location.

Applications

• Mucosal Lesions: Punch biopsies are particularly useful for obtaining samples from mucosal lesions in areas such as:

  • Oral cavity (e.g., lesions on the tongue, buccal mucosa, or gingiva)
  • Nasal cavity
  • Anus
  • Other inaccessible regions where traditional biopsy methods may be challenging.

• Skin Lesions: While primarily used for mucosal lesions, punch biopsies can also be performed on skin lesions to diagnose conditions such as:

  • Skin cancers (e.g., melanoma, basal cell carcinoma)
  • Inflammatory skin diseases (e.g., psoriasis, eczema)

Advantages

• Minimal Invasiveness: The punch biopsy technique is relatively quick and minimally invasive, making it suitable for outpatient settings.
• Preservation of Tissue Architecture: The cylindrical nature of the sample helps preserve the tissue architecture, which is important for accurate histopathological evaluation.
• Accessibility: It allows for sampling from difficult-to-reach areas that may not be accessible with other biopsy techniques.

Limitations

• Tissue Distortion: As noted, the punch biopsy technique can produce some degree of crushing or distortion of the tissues. This may affect the histological evaluation, particularly in delicate or small lesions.
• Sample Size: The size of the specimen obtained may be insufficient for certain diagnostic tests, especially if a larger sample is required for comprehensive analysis.
• Potential for Scarring: Depending on the size of the punch and the location, there may be a risk of scarring or changes in the appearance of the tissue after healing.

Dry Socket (Alveolar Osteitis)

Dry socket, also known as alveolar osteitis, is a common complication that can occur after tooth extraction, particularly after the removal of mandibular molars. It is characterized by delayed postoperative pain due to the loss of the blood clot that normally forms in the extraction socket.

Key Features

1. Pathophysiology:

   • After a tooth extraction, a blood clot forms in the socket, which is essential for healing. In dry socket, this clot is either dislodged or dissolves prematurely, exposing the underlying bone and nerve endings.
   • The initial appearance of the clot may be dirty gray, and as it disintegrates, the socket may appear gray or grayish-yellow, indicating the presence of bare bone without granulation tissue.

2. Symptoms:

   • Symptoms of dry socket typically begin 3 to 5 days after the extraction. Patients may experience:
     • Severe pain in the extraction site that can radiate to the ear, eye, or neck.
     • A foul taste or odor in the mouth due to necrotic tissue.
     • Visible empty socket with exposed bone.

3. Local Therapy:

   • Management of dry socket involves local treatment to alleviate pain and promote healing:
     • Irrigation: The socket is irrigated with a warm sterile isotonic saline solution or a dilute solution of hydrogen peroxide to remove necrotic material and debris.
     • Application of Medications: After irrigation, an obtundent (pain-relieving) agent or a topical anesthetic may be applied to the socket to provide symptomatic relief.

4. Prevention:

   • To reduce the risk of developing dry socket, patients are often advised to:
     • Avoid smoking and using straws for a few days post-extraction, as these can dislodge the clot.
     • Follow postoperative care instructions provided by the dentist or oral surgeon.

Bone Healing: Primary vs. Secondary Intention

Bone healing is a complex biological process that can occur through different mechanisms, primarily classified into primary healing and secondary healing (or healing by secondary intention). Understanding these processes is crucial for effective management of fractures and optimizing recovery.

Secondary Healing (Callus Formation)

• Secondary healing is characterized by the formation of a callus, which is a temporary fibrous tissue that bridges the gap between fractured bone fragments. This process is often referred to as healing by secondary intention.

• Mechanism:

  • When a fracture occurs, the body initiates a healing response that involves inflammation, followed by the formation of a soft callus (cartilaginous tissue) and then a hard callus (bony tissue).
  • The callus serves as a scaffold for new bone formation and provides stability to the fracture site.
  • This type of healing typically occurs when the fractured fragments are approximated but not rigidly fixed, allowing for some movement at the fracture site.

• Closed Reduction: In cases where closed reduction is used, the fragments are aligned but may not be held in a completely stable position. This allows for the formation of a callus as the body heals.

Primary Healing (Direct Bone Union)

• Primary healing occurs when the fractured bone fragments are compressed against each other and held in place by rigid fixation, such as with bone plates and screws. This method prevents the formation of a callus and allows for direct bone union.

• Mechanism:

  • In primary healing, the fragments are in close contact, allowing for the migration of osteocytes and the direct remodeling of bone without the intermediate formation of a callus.
  • This process is facilitated by rigid fixation, which stabilizes the fracture and minimizes movement at the fracture site.
  • The healing occurs through a process known as Haversian remodeling, where the bone is remodeled along lines of stress, restoring its structural integrity.

• Indications for Primary Healing:

  • Primary healing is typically indicated in cases of:
    • Fractures that are surgically stabilized with internal fixation devices (e.g., plates, screws).
    • Fractures that require precise alignment and stabilization to ensure optimal healing and function.