Dental Extractions Overview

Extractions

• Most commonly affected teeth are mandibular and maxillary third molars, and maxillary canines.
• Impacted teeth and congenitally missing teeth are also common.
• Maxillary and mandibular third molars, and mandibular second premolars, and maxillary lateral incisors are most commonly affected.
• Indications for extractions include severe caries, endodontic issues, internal root resorption, periodontal issues, attachment loss, orthodontic issues, and severe tooth crowding.
• Contraindications include poorly controlled medical conditions (like diabetes or bleeding disorders), immunocompromised conditions (leukemia, lymphoma), a history of head and neck radiation, increased risk of osteoradionecrosis, history of bisphosphonates, and increased risk of medication-related osteonecrosis of the jaw (MRONJ).

Extraction Procedure

• Initial movements for extractions are typically buccal then lingual, due to the thinner buccal plate.

• Rotary movement is used for single-rooted teeth, while apical pressure is used to expand the socket.

• Surgical extractions may be necessary in cases of long or divergent roots, endodontic treatment, crown fracture, and retained roots.

• These procedures often involve a full-thickness buccal flap to avoid lingual nerve damage, buccal bone removal, and interradicular or cortical bone sectioning.

• Most initial movements in the procedure are buccal, then lingual (due to the thinner buccal plate).

• Rotary movement used for single-rooted teeth

• Apical pressure to expand the socket

• Third molar extractions aim to eliminate periodontal problems, alleviate pain, and allow cleaning of second molars.

• Maxillary third molars are delivered distobuccally.

• Primary closure involves a physical closure of the wound after surgery.

• Secondary closure involves leaving the wound open; healing occurs by granulation and contraction.

• Post-op instructions include gauze pressure, a soft diet, no negative pressure, no smoking, and a salt water rinse after 24 hours.

Complications

• Subperiosteal abscess can occur from infection under the periosteum due to trapped necrotic bone or tooth. Treatment involves irrigation to remove the bone or tooth.
• Oro-antral communication (sinus exposure) involves the exposure of the sinus with maxillary first and second molars. Signs include 2 mm or less, 2-6mm and more than 6mm.
• Alveolar osteitis (dry socket) is a multifactorial issue, associated with oral contraceptive use, smoking, and using straws and can be treated with pain control.
• Nerve injury is a potential complication, especially with mandibular third molar extractions (IAN block).
• Tooth displacement is another potential complication, depending on the molar location: maxillary sinus, infratemporal fossa, or submandibular space.
• Bleeding is a common complication that can be managed with gauze pressure, sutures, and hemostatic agents.

Flap Design

• Considerations include a wide base, over intact bone, vertical releases at line angles, and avoiding vital structures (arteries, nerves, thin tissue).
• Flap types include trapezoid, envelope, and 3-cornered flaps.
• Differences are based on the number of vertical releases. (0, 1, and 2).
• Different flaps are used for different areas of the mouth and also for apicoectomy (surgical removal of the apex of a tooth root), particularly for maxillary anterior teeth.

Grafting

• Types and sources: Autograft (same individual), Allograft (same species), Alloplastic (synthetic or natural materials), Xenograft (other species).
• Grafting techniques are used to preserve ridges, restore bony defects, or increase ridge thickness.
• Key aspects for grafting success are immunocompatibility, scaffold availability, presence of signals for tissue growth, and tissue growth capacity.

Implants

• Endosteal implants are the most commonly-used type of implant.
• Implant components include the implant body, cover screw, second stage surgery, implant analogue, abutment and screw, healing abutment, and impression copings.
• Implant body is made of titanium, highly biocompatible, with varying diameters and lengths.
• Forces exerted on implants are vertical, oblique, and horizontal, which are accounted for in implant design and placement.
• Implant placement is guided by measurements such as distance from buccal/lingual plate, inferior border of mandible, maxillary sinus, and nasal cavity; minimum space requirements for teeth; from adjacent natural teeth; the IAN, adjacent implants, and mental nerve; and typical width of 4 mm.

Stability

• Primary stability refers to the initial biomechanical stability of the implant.
• Secondary stability relates to the long-term osseointegration of the implant.

Trauma & Surgery

• Le Fort fractures are categorized into I, II, and III types, each involving different parts of the midface and nasal bones.
• Orthognathic surgery is relevant for retrusive or protrusive mandible (such as Bisagittal split osteotomy [BSSO]) and vertical maxillary excess.
• Mandibular fractures are common, categorized by location (condyle, angle, symphysis), and whether the fracture is closed or open (does it break the skin). Treatment involves simple, compound, greenstick, and comminuted types of fractures.

Trauma to Permanent Teeth

• Different degrees of tooth displacement/trauma, and the appropriate treatment approaches, are discussed (concussion, subluxation, lateral luxation, intrusion, avulsion, extrusion, and types of fractures).
• Different types of splinting/treatment timeframes are given for each type of trauma.
• Cytology/brush and fine needle aspiration are biopsy techniques used to diagnose oral tissue lesions.

Wound Healing

• Stages of wound healing are discussed in relation to oral trauma, including the initial hemostasis (clotting), inflammation stages, proliferation (cell growth and tissue repair), and maturation (long-term healing). Processes like vasoconstriction, blood clot formation, and macrophage migration are part of wound healing.
• Temporal issues are important to consider when discussing TMJ jaw movement and disc displacement as maximum opening or deviation issues.
• Maximal opening and deviation of jaw opening can be affected by disc displacement, and issues with reduction/no reduction and deviations to one side.

TMJ

• Disc displacement with and without reduction are examined as possible TMJ issues.
• Understanding of the various opening patterns (deflection, deviation) and possible pathologies (dislocation, ankylosis) is crucial.

Medical Emergencies

• Conditions such as angina, myocardial infarction, epinephrine overdose, stroke, and diabetic complications are presented as possible medical emergencies in the oral and maxillofacial surgery setting. Symptoms, treatments, and preventive measures are provided for each condition.
• Conditions such as anaphylactic shock, airway obstruction, asthma, hyperventilation, are covered to cover the broad range of issues that can impact the patient in the operating room. Symptoms, treatments, and preventive measures are provided for each condition.