Adjunctive and Prophylactic Use of Antibacterial Agents in Dentistry
Course Number: 475
Course Contents
Primary Dental Care
Reversible Pulpitis
Patients with reversible pulpitis usually report sensitivity or pain in response to hot, cold, sweets, and mechanical stimuli. Caries in proximity of the pulp, defective restorations, exposed dentinal tubules, and traumatic occlusion appear to be common etiologies. Provoked pain, described as sharp or intense, primarily reflects hyperemia or mild inflammation of the pulp and stimulus-induced fluid movement in dentinal tubules.
Reversible pulpitis is a reactive process. Caries should be excavated and a temporary sedative restoration placed. Faulty restorations should be removed and replaced. Exposed dentinal tubules should be etched and sealed. To reduce inflammation and shorten recovery time a disease-modifying analgesic, i.e., a nonsteroidal anti-inflammatory drug (NSAIDs) should be prescribed. It is intuitive that antibacterial agents would have no effect on clinical outcome.80
Irreversible Pulpitis
Bacteria may gain access to the pulpal system through caries, defective restorations, and exposed dentinal tubules. Other portals may include apical, lateral, or furcation canals associated with advancing periodontal disease. Pain may be spontaneous, but usually it is in response to hot, cold, sweets, and mechanical stimuli reflects hyperemia or inflammation secondary to infection, fluid movement in dentinal tubules, and increased intrapulpal pressure.
Acute dental pain associated with a tooth with deep carious lesion may reflect a reactive process to caries, but most likely to bacteria that have infected pulpal tissues.80-86 In case of irreversible pulpitis endodontic debridement and obturation of the root canal system is the most predictable method of treatment.87 To reduce inflammation and shorten recovery time a disease-modifying analgesic, i.e., a NSAID should be prescribed.
In untreated irreversible pulpitis, penicillin does not reduce spontaneous pain, percussion induced pain, or the amount of analgesics taken by patients.88,89 In a prospective study, a five-day course of penicillin administered to patients with acute pain related to a tooth with an amalgam restoration without clinical signs of infection, in the absence of definitive dental care, did not prevent the emergence of clinical signs of infection within 5 days.90
Acute Apical Periodontitis
Irreversible pulpitis and pulpal necrosis (an asymptomatic complication of irreversible pulpitis), if left untreated, lead to the spread of irritants and bacteria into periradicular tissues and result in acute apical periodontitis. Patients complain of tenderness or mild to moderate pain associated with the apical area of the offending tooth. The pain may be intermittent, secondary to manipulation of the tooth, or unprovoked and continuous.
The removal of bacteria and their byproducts by debridement and obturation of the root canal system effectively eliminates infection, curtails inflammation, and promotes healing. The administration of a disease modifying analgesic, i.e., a NSAID, may shorten recovery time. It has been shown that once the source of infection is eliminated, the administration of penicillin provides no statistically significant added benefit.91
Acute Apical Abscess
Infection associated with acute apical periodontitis may extend into alveolar bone and soft tissues initiating apical abscess formation. The pain is usually severe, unprovoked and constant. The tooth is usually mobile and the accumulation of fluid in the periodontal ligament space may cause supraeruption. Manipulation of the tooth causes exquisite sensitivity and mastication is difficult; swelling, malaise and fever may be present.80
The removal of bacteria and their byproducts by debridement and obturation of the root canal system effectively eliminates infection, curtails inflammation, and promotes healing. The swelling, when present, may be drained through the tooth, by a soft tissue incision, or there may already be drainage through a naturally occurring sinus tract. A disease modifying analgesic, i.e., a NSAID, may shorten recovery time.
In a prospective study, a five-day course of penicillin administered to patients with acute pain related to a tooth with large periapical radiolucency, but without clinical signs of infection, in the absence of debridement did not prevent the development of clinical signs of infection within 5 days.90 Another study confirmed that once the source of infection is eliminated, the administration of penicillin provides no statistically significant added benefit.92
Draining Sinus Tract
Inflammatory degeneration of the pulp and periradicular tissues may follow a chronic subclinical course. The infection progresses slowly through cancellous bone along the path of least resistance. It perforates the thin cortical plate and forms a subperiosteal abscess. Once through the periosteum, it spreads into surrounding soft tissues and leads to the formation of either an intraoral or extraoral draining sinus tract; swelling and pain are usually absent.93
In restorable teeth, chronic draining sinus tracts will respond to nonsurgical endodontic therapy. Successful healing depends on optimal debridement and obturation of the canal system. Non-restorable teeth and/or those with extensive alveolar bone loss require extraction. There is no evidence that the routine administration of an antibacterial agent improves therapeutic outcome.93 The residual cutaneous defect or scar may require subsequent surgical revision.
Gingival Abscess
Gingival abscess is a localized, rapidly evolving, painful infection of the marginal or interdental gingiva usually secondary to the impaction of foreign bodies, e.g., popcorn shells, peanut husks, seeds, fish bones, toothbrush bristles, or toothpick splinters into the gingival crevice.94 The abscess may drain through the crevice or a draining sinus tract through the gingiva. Affected teeth may be extruded and tender to percussion.
Foreign objects tend to adhere to the soft tissue wall of the gingival crevice. Following the application of a topical anesthetic agent, the gingival tissue should be gently distended; the foreign object removed, the soft tissue wall of the lesion should be gently curetted to induce drainage, and the area should be irrigated with warm saline. The patient should continue to rinse with warm saline every 2 hours for two days. Routine antibacterial therapy is not indicated.
Periodontal Abscess
A periodontal abscess may be secondary to impacted foreign objects into the orifice of a periodontal pocket, closure or narrowing of the pocket orifice, or improper use of irrigating devices.94 Mild to moderate pain may be acute or chronic. The swelling rarely spreads beyond the mucogingival junction and may be associated with a draining sinus tract located in the gingival crevice or at the mucogingival junction.
Drainage should be established with the careful use of a periodontal probe. Once the opening to the pocket is located, the root surface should be gently debrided. If drainage cannot be established through the orifice of the pocket, a vertical incision should be made and the area should be irrigated with warm saline. The patient should continue to rinse with warm saline every 2 hours for two days. Routine antibacterial therapy is not indicated.
Necrotizing Ulcerative Gingivitis
Necrotizing ulcerative gingivitis (NUG) is characterized by localized necrosis and ulceration usually of the interdental papillae, which may extend to the marginal gingiva and rarely the whole mouth.94 Microorganisms have been implicated, but it is unclear if they are causative or opportunistic. Patients report a putrid odor, a foul metallic taste, and constant radiating pain intensified by spicy or hot foods, and gentle probing.
The initial treatment of necrotizing ulcerative gingivitis includes gentle irrigation of the affected areas with warm saline; followed by careful curettage of necrotic/ulcerative lesions and root surfaces to reduce the bioburden. Patients are instructed to rinse with warm saline every 2 hours and undergo daily repeat debridement until the lesions have resolved. Routine antibacterial therapy is not indicated and response to debridement is noted within 2-3 days. Patients may require gingivoplasty to correct residual crater-like gingival defects.
Alveolar Osteitis
Alveolar osteitis is a relatively common complication of tooth extraction, usually of mandibular molars. A foul taste, putrid odor, and deep, radiating pain of increasing intensity is noted three to four days following extraction. The surrounding soft tissues appear normal but the alveolar socket is empty or contains necrotic debris. Alveolar osteitis is primarily an inflammatory condition, which may become secondarily infected.
A common protocol to manage alveolar osteitis consists of gentle debridement of the socket, irrigation with warm saline, and placement of an iodophor gauze impregnated with eugenol. The patient should be reevaluated every 24 to 48 hours, the dressing removed, the socket irrigated with warm saline and redressed. This cycle may have to be continued for up to 14 days. Routine antibacterial therapy is not indicated.
Pericoronitis
Pericoronitis is an acute infection most often associated with soft tissue overlying a partially erupted mandibular third molar. Signs and symptoms include pain, malaise, fever, lymphadenopathy, trismus, and difficulty swallowing. Abscess formation may be evident buccally or lingually to the offending tooth, which may progress to cellulitis or osteomyelitis; or spread through the fascial planes of the head and neck.
To establish drainage from under the operculum, a periodontal probe should be inserted into the follicular space enlarging the opening. The area under the operculum should be irrigated with warm saline and iodophor gauze impregnated with eugenol placed to maintain drainage. If the opposing maxillary tooth is traumatizing the operculum and deemed nonfunctional, it may be extracted. Otherwise, the cusps may be slightly reduced to minimize further trauma to the soft tissue below.
The patient should rinse with warm saline every 2 hours. Depending on associated signs and symptoms, i.e., clinical evidence of induration as the infection is spreading buccally or lingually and the presence of trismus, empirical antibacterial therapy may be initiated. When a subacute condition has been attained, usually within 48 hours, and the tooth is to be maintained, the operculum should be removed at this time; otherwise, the tooth may now be extracted.
Cellulitis
When pulpal, periodontal or pericoronal infections overwhelm host resistance, the infection may extend into the surrounding tissues and cause cellulitis.95-97 The affected area becomes edematous and feels indurated when palpated suggesting diffuse inflammation. Patients present with pain, malaise, trismus, regional lymphadenopathy, and fever. The tissues overlying the infected area may appear bluish.
Patients with cellulitis should be referred to a surgical specialist who may collect a sample of the purulent exudate, usually by aspiration, and initiate empirical, usually oral antibacterial chemotherapy. As the infection consolidates and becomes fluctuant, it will be incised at its most dependent area, the purulent material evacuated, and a drain inserted. Once a subacute condition has been attained appropriate primary dental intervention should be initiated.
Osteomyelitis
Osteomyelitis is another potential complication of odontogenic infection. It most often affects cancellous medullary bone of the mandible. As purulence accumulates, it restricts blood flow to the area, which causes osseous necrosis and the formation of sequestrum. Signs and symptoms include paresthesia or deep persistent pain, malaise, fever, lymphadenopathy, loose teeth, and in the later stages, alveolar radiolucencies.
When osteomyelitis is suspected, the patient should promptly be referred to a surgical specialist who will collect a sample of the purulent exudate, usually by aspiration, for culture and susceptibility testing and begin immediate empirical, usually intravenous antibacterial chemotherapy. Drainage is established at the earliest possible time. Close monitoring and modification of antibacterial chemotherapy, if indicated, is imperative.
Space Infections
The inflammatory process associated with cellulitis is usually restricted to the jaws. However, if timely treatment is not initiated, the infection may spread through the fascial planes of the head and neck into the canine, buccal, masticatory, submental, sublingual, submandibular, vestibular, parotid, parapharyngeal, retropharyngeal, and deep spaces of the head and neck and mediastinum creating life-threatening situations.
When space infection is suspected, the patient should immediately be referred to a surgical specialist for evaluation and management. The specialist will collect a sample of the purulent exudate, usually by aspiration, for culture and susceptibility testing and begin immediate empirical intravenous antibacterial chemotherapy.95-98 Drainage is established at the earliest possible time and measures to protect the airway are instituted if necessary. Close monitoring and modification of antibacterial chemotherapy, if indicated, is imperative.