Relevant Anatomy Abscesses that are drained by intraoral incision include: Periodontal abscess originating between the tooth and its gum line, with possible extension into adjacent fascial spaces (eg, vestibular or buccal space) Periapical abscess that has spread through the tooth, out the apex, through the surrounding bone, and into the surrounding soft tissues / fascial spaces Positioning Position the patient inclined, with the patient's head at the level of your elbows and the occiput supported.