Dental caries and oral-health prevention — structured clinical encounter

Candidate instructions

You are the paediatric registrar in the clinic. You have ten minutes to assess this three-year-old and present your assessment and management plan to the examiner. You are expected to take a focused oral-health and feeding history, examine the mouth, state the diagnosis and its case definition, stratify the caries risk, and outline a prevention and management plan. The examiner will then release a second scenario of a four-year-old with a swollen face and trismus, and will ask you to recognise the emergency and outline the immediate management. [6]

Encounter

On taking the history, the child has fallen asleep each night with a bottle of sweetened milk since infancy, takes sugary snacks between meals, and brushing is inconsistent and unsupervised. The family has no dental home and the water supply is not fluoridated. On examination, the maxillary anterior primary teeth show chalky white spots and brown cavitated lesions, the lower anterior primary teeth are spared, and there is no gingival swelling, sinus, facial swelling or fever. She is well and thriving. [6] [7]

The candidate recognises early childhood caries in its classic pattern — smooth-surface caries of the maxillary anterior primary teeth, sparing the lower anterior teeth — and states the American Academy of Pediatric Dentistry case definition of any decayed, missing or filled primary tooth surface in a child 71 months or younger. The candidate stratifies her as high caries risk from the nocturnal sugary bottle, the unsupervised brushing, the non-fluoridated water and the absence of a dental home. [6]

Marking domains

History and examination (3 marks). The candidate elicits the nocturnal sugary bottle, the snacking and the brushing pattern, and examines the mouth systematically, lifting the lip to identify the caries pattern and exclude swelling, sinus and the red flags of spreading infection. [6]

Diagnosis and case definition (3 marks). The candidate names early childhood caries, states the AAPD age cut-off of 71 months, and explains the pathophysiology — an acidogenic Streptococcus mutans-dominated biofilm dropping the plaque pH below the critical value of about 5.5 for enamel — and why the upper front teeth are affected and the lower spared. [7] [8]

Prevention and management plan (4 marks). The candidate advises stopping the nocturnal bottle, twice-daily brushing with a pea-sized amount of a fluoride toothpaste of at least 1000 parts per million (the age-appropriate amount for three to six years), spit-not-rinse, supervised brushing until around seven to eight years, reduction of free sugars, fluoride varnish two to four times a year, and establishment of a dental home with close recall. For the cavitated lesions, the candidate offers silver diamine fluoride with appropriate counselling about the permanent black stain, or restorative or theatre-based care for extensive disease. [2] [4]

Differential and the second scenario (2 marks). The candidate distinguishes caries from the developmental enamel defects — molar-incisor hypomineralisation, amelogenesis imperfecta and fluorosis — by whether the enamel was formed wrongly or is being dissolved. On release of the second scenario of a four-year-old with a swollen face, fever and trismus from a necrotic molar, the candidate recognises a spreading odontogenic infection, prioritises airway assessment and securing, intravenous antibiotics with anaerobic cover, and urgent dental or maxillofacial referral for drainage and source control, and selects computed tomography if a deep-space infection or airway compromise is suspected. [9] [10] [11]