ENT · Oral Pathology
The facts most likely to be tested
Streptococcus mutans is the primary cariogenic pathogen responsible for the production of biofilm and lactic acid that demineralizes tooth enamel.
Fluoride supplementation promotes remineralization of enamel and inhibits bacterial enoyl-ACP reductase to prevent cavity progression.
Early Childhood Caries (ECC) is characterized by the rapid destruction of primary maxillary incisors due to prolonged exposure to fermentable carbohydrates, often from bottle-feeding at night.
Xerostomia, frequently caused by Sjogren syndrome or anticholinergic medications, significantly increases the risk of cervical caries due to the loss of the protective, buffering effects of saliva.
Dental radiographs (bitewings) are the gold standard for detecting interproximal caries that are not clinically visible during a physical examination.
Silver diamine fluoride is a non-invasive topical agent used to arrest active dentinal caries by promoting remineralization and exhibiting potent antimicrobial properties.
Pulpitis is the most common complication of untreated deep caries, presenting as sharp, throbbing pain that is exacerbated by thermal stimuli.
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A 3-year-old boy is brought to the clinic for a routine check-up. The mother reports that the child frequently falls asleep with a bottle containing milk. On physical examination, the maxillary incisors show chalky white spots and brown cavitated lesions at the gingival margin. The mandibular incisors appear unaffected. The child is otherwise healthy and has no history of systemic illness.
What is the most likely diagnosis?
Early Childhood Caries
The clinical presentation of localized decay on the maxillary incisors in a toddler with a history of nocturnal bottle-feeding is pathognomonic for Early Childhood Caries, as described in Bet 3.
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Etiology / Epidemiology
Caused by Streptococcus mutans fermentation of dietary carbohydrates. Poor oral hygiene and frequent sugar intake are primary risk factors.
Clinical Manifestations
Presents as chalky white spots progressing to cavitation. Patients report localized tooth pain with thermal or sweet stimuli.
Diagnosis
Diagnosis is primarily clinical inspection supplemented by bitewing radiographs to identify interproximal lesions.
Treatment
Management includes topical fluoride application and dental restoration (fillings). Avoid sugar-sweetened medications in pediatric patients.
Prognosis
Untreated caries lead to periapical abscess or cellulitis. Regular biannual dental exams prevent progression.
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Epidemiology & Etiology
Dental caries is the most common chronic disease in children and adults. The process is driven by biofilm (plaque) accumulation on the enamel surface. High-risk groups include those with xerostomia, low socioeconomic status, and high-sucrose diets.
Pertinent Anatomy
The enamel is the highly mineralized outer layer susceptible to acid demineralization. The dentin layer lies beneath; once caries reach this depth, pain sensitivity increases significantly. The pulp contains neurovascular structures, and involvement indicates advanced disease.
Pathophysiology
Bacteria metabolize carbohydrates into lactic acid, which lowers the local pH below the critical pH of 5.5. This triggers the dissolution of hydroxyapatite crystals. If the process is not reversed by remineralization (via saliva and fluoride), the enamel structure collapses into a cavity.
Clinical Manifestations
Early lesions appear as white spot lesions representing subsurface demineralization. Advanced caries present as brown/black cavitation with soft, sticky texture upon probing. Red flags include facial swelling, trismus, or fever, suggesting a deep space infection.
Diagnosis
Diagnosis relies on visual-tactile examination using a dental explorer. Bitewing radiographs are the gold standard for detecting interproximal caries not visible to the naked eye. Transillumination can be used as an adjunct for anterior teeth.
Treatment
Early non-cavitated lesions are managed with topical fluoride and improved hygiene. Cavitated lesions require mechanical removal of decay and placement of composite resin or amalgam restorations. Avoid prolonged use of sugar-containing syrups in children to prevent nursing bottle caries.
Prognosis
Untreated caries progress to pulpitis, which may necessitate root canal therapy or extraction. Severe cases can lead to Ludwig's angina or systemic sepsis. Biannual dental cleanings are required for long-term prevention.
Differential Diagnosis
Dental erosion: loss of enamel due to chemical acid (e.g., GERD) rather than bacterial fermentation
Dental attrition: mechanical wear from bruxism
Dentin hypersensitivity: pain without visible cavitation
Periodontitis: inflammation of supporting structures rather than tooth structure
Hypoplasia: developmental enamel defects present at eruption