1.    What are the major sources of odontogenic infections?

The two major sources of odontogenic infection are periapical disease, which occurs as a consequence of pulpal necrosis, and periodontal disease.

2.    What are the three clinical stages of odontogenic infection?

1.     Periapical osteitis occurs when the infection is localized within the alveolar bone. Although the tooth is sensitive to percussion and often slightly extruded, there is no soft tissue swelling.

2.     Cellulitis develops as the infection spreads from the bone to the adjacent soft tissue. Subsequently, inflammation and edema occur, and the patient develops a poorly localized swelling. On palpation the area is often sensitive, but the sensitivity is not discrete.

3.     Suppuration then occurs and the infection localizes into a discrete, fluctuant abscess.

3.    What are the significant complications of untreated odontogenic infection?

·   Tooth loss

·   Spread to the cavernous sinus and brain

·   Spread to the neck with large vein complications

·   Spread to potential fascial spaces with compromise of the airway

·   Septic shock

4. What are the major sources of odontogenic infections?

The two major sources of odontogenic infection are periapical disease, which occurs as a consequence of pulpal necrosis, and periodontal disease.

5. What are the three clinical stages of odontogenic infection?

1.     Periapical osteitis occurs when the infection is localized within the alveolar bone. Although the tooth is sensitive to percussion and often slightly extruded, there is no soft tissue swelling.

2.     Cellulitis develops as the infection spreads from the bone to the adjacent soft tissue. Subsequently, inflammation and edema occur, and the patient develops a poorly localized swelling. On palpation the area is often sensitive, but the sensitivity is not discrete.

3.     Suppuration then occurs and the infection localizes into a discrete, fluctuant abscess.

6.   What are the significant complications of untreated odontogenic infection?

·   Tooth loss

·   Spread to the cavernous sinus and brain

·   Spread to the neck with large vein complications

·   Spread to potential fascial spaces with compromise of the airway

·   Septic shock

What are the principles of therapy for odontogenic infections as

  defined by Peterson?

1.    Determine the severity of the infection.

2.    Evaluate the state of the host defense

3.   Determine whether the patient should be treated by a general dentist or a  specialist.

3.    Treat the infection surgically.

4.    Support the patient medically.

5.    Choose and prescribe the appropriate antibiotic

6.    Administer the antibiotic properly.

7.    Evaluate the patient frequently.

7.    What is the treatment of choice for an odontogenic abscess?

The treatment of choice for an odontogenic abscess is incision and drainage, which may be accomplished in one of three ways: (1) exposure of the pulp chamber with extirpation of the pulp, (2) extraction of the tooth, or (3) incision into the soft-tissue surface of the abscess. Antibiotic therapy is indicated in the presence of fever or lymphadenopathy.

8.   How is incision and drainage of soft tissue best performed?

Local anesthesia should be obtained first. Care must be taken not to inject through the infected area and thus spread the infection to noninvolved sites. Once adequate anesthesia has been obtained, an incision should be placed at the most dependent part of the swelling. The incision should be wide enough to facilitate drainage. Blunt dissection is often helpful. After irrigation, a drain of either iodoform gauze or rubber should be placed to maintain the patency of the wound. Postoperative instructions should include frequent rinses with warm saline, appropriate pain medication, and, when indicated, antibiotic therapy. The patient should be instructed to return for follow-up evaluation in 24 hours.

9.   When infection erodes through the cortical plate, it does so in a predictable manner. What factors determine the location of infection from a specific tooth?

·   Thickness of bone overlying the tooth apex; the thinner the bone, the more likely it is to be perforated by spreading infection.

·   The relationship of the site of bony perforation to muscle attachments to the maxilla or mandible.

10. State the usual site of bone perforation, the relationship to muscle attachment, the de termining muscle, and the site of localization for each tooth for odontogenic infections.

Involved Teeth	Usual Site of Peiforation of Bone	Relation of Perforation to Muscle Attachment	Determining Muscle	Site of Localization
maxilla
Central incisor	Labial	Below	Orbicularis oris	Labial vestibule
Lateral incisor	Labial	Below	Orbicularis oris	Labial vestibule
	(palatal)*	-	-	(palatal)
Canine	Labial	Below	Levator anguli oris	Oral vestibule
	Labial	(above)	Levator anguli oris	(Canine space)
Premolars	Buccal	Below	Bucci nator	Buccal vestibule
Molars	Buccal	Below	Bucci nator	Buccal vestibule
	Buccal	Above	Bucci nator	Buccal space
	(palatal)	-	-	(palatal)
Mandible
Incisors	Labial	Above	Mentalis	Labial vestibule
Canine	Labial	Above	Depressor anguli oris	Labial vestibule
Premolars	Buccal	Above	Bucci nator	Buccal vestibule
First molar	Buccal	Above	Bucci nator	Buccal vestibule
	Buccal	Below	Bucci nator	Buccal space
	Lingual	Above	Mylohyoid	Sublingual space
Second molar	Buccal	Above	Bucci nator	Buccal vestibule
	Buccal	Below	Bucci nator	Buccal space
	Lingual	Below	Mylohyoid	Sublingual space
	Lingual	Below	Mylohyoid	Submandibualr space
Third molar	Lingual	Below	Mylohyoid	Submandibualr space