Figure 2-7.—Removing debris from the cavity.

tooth. If the pulp cannot resist the irritation caused by the caries, it will die. SYMPTOMS—The patient may complain that the affected tooth is sensitive to heat and cold (usually cold), to sweets, or to pressure from food particles impacted in the cavity. Sometimes a patient will point to a healthy tooth and complain that it aches. There may be trouble in such a tooth, but it is always advisable to examine the other teeth on the same side (both upper and lower arches) for a cavity. This may be referred pain; that is, a patient feels pain in a healthy tooth while the true cause of the pain is located elsewhere. SIGNS—Examine the patient for caries by using a mouth mirror, an explorer, a cotton forceps, and a spoon excavator. Locate the af- fected tooth by asking the patient to point to it. You may observe some of the following signs. Chalky white spot on tooth surface Surface roughness when explorer point passes lightly over tooth Dark, stained cavity Cavity filled with spongy mass of decaying dentin Find out the depth of the caries. To do this, you may have to remove loose debris from the cavity. Use the spoon excavator and very gently lift out the debris as illustrated in figure 2-7. NOTE: Never try to scrape or dig the debris from the interior of the tooth. Stop the examination if there is bleeding in the pulp area, if the pulp is exposed, or if the patient’s pain is greatly increased. If there is no pulpal bleeding or exposure or increased pain, continue removing the debris. When all of it is removed, lightly dry the interior of the tooth with a cotton pellet as shown in figure 2-8. Do not use air or extreme pressure in drying the tooth. TREATMENT—The following is a treatment plan for a tooth with no pulpal opening. For a tooth with a pulpal opening, see the treatment plan for acute pulpitis. 267.49 Figure 2-7.—Removing debris from the cavity. 267.50 Figure 2-8.—Preparing to dry the cavity. If you have not done so before, remove all debris from the cavity with an excavator, and flush the cavity with warm water. Isolate the tooth with cotton rolls to free the cavity of saliva. If the tooth is in the mandibular arch, cotton roll holders will be helpful in isolating it. You can easily isolate a tooth in the maxillary arch by placing cotton rolls between the arch and the cheek or lip, depending upon the location of the cavity. Carefully dry the interior of the cavity with clean cotton pellets. Mix a zinc oxide-eugenol 2-45