Dry mouth, nine root lesions and a sipper bottle of cordial
Mrs W is 71 and attends for a scale. Her medications are oxybutynin 5 mg three times daily, sertraline 100 mg and lercanidipine. She has a dry mouth, drinks water constantly and has trouble swallowing dry food. She has nine teeth with root-surface lesions: three on the upper anteriors are soft and leathery on probing; the rest are hard and dark. Gingival margins are receded with plaque stagnation. She uses a 5000 ppm fluoride toothpaste prescribed by her dentist, but brushes once a day in the morning, rinses with a chlorhexidine mouthwash afterwards, and drinks a 'no added sugar' blackcurrant cordial containing citric acid from a sipper bottle throughout the day. She sucks sugar-free lozenges and has recently started chewing sugar-free gum. She dislikes the taste of fluoride varnish, cannot afford multiple visits, and will not accept black staining on the front teeth. She asks whether she should just have the teeth out.
1. Assess her caries risk, classify the root lesions, and outline your management priorities, including whether restoration or extraction is warranted.
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Risk level: high. Multiple factors converge - medication-induced xerostomia (oxybutynin is strongly anticholinergic and sertraline adds to it), widespread root exposure, nine root lesions with three active, plaque stagnation at the gingival margins, frequent acid exposure through the day, once-daily brushing, and rinsing after brushing which removes the fluoride. Cost is a further barrier to care.
Classifying the lesions. Probe gently and look. An active root lesion is soft, leathery or tacky, often with plaque stagnation and close to the gingival margin; an arrested lesion is hard, dark and often shiny. The three soft upper anterior lesions are active and need intervention; the hard, dark ones are arrested and need protection, not drilling. Record site and texture, and photograph them so you can tell change from no change at review.
Restoration or extraction? Root caries does not automatically mean extraction, and 'just take them all out' is a fear to be explored, not a treatment plan. Restore only where a lesion is cavitated and uncleansable, where the pulp is involved, or where the tooth is symptomatically broken down - often with glass ionomer, which releases fluoride. Many active root lesions can be arrested with fluoride and plaque control, particularly where access for restoration is poor.
Priorities. First modify the drivers: fluoride delivery, saliva, diet frequency, plaque removal at the gingival margin. Then reassess at three months. Reassurance matters - tell her that keeping her teeth is a realistic goal and say specifically what you will do to try.
2. Design a fluoride and remineralisation regimen that fits her preferences and budget. Justify each component and state what you would not use.
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Toothpaste. 5000 ppm fluoride is the right strength, but the routine is wrong. Twice daily, including last thing at night, spit and do not rinse - no water and no mouthwash afterwards. Chlorhexidine is not a caries-prevention agent, and using it after brushing washes the fluoride off; if it is needed for gingivitis, use it at a separate time and for a defined period.
Professional varnish. 5% sodium fluoride varnish (22,600 ppm) at least twice a year, and up to four times a year with active lesions, applied to root surfaces and gingival margins. She dislikes the taste and cost is a constraint - be honest that this is the cheapest effective intervention available, and schedule it around the visits she can afford.
Silver diamine fluoride. 38% SDF arrests active root caries, but it stains the lesion black and tastes metallic. She has refused staining on the front teeth, so offer SDF on the posterior active lesions only, protect the gingivae with petroleum jelly, and use varnish on the upper anteriors. Warn her that any soft tissue contact irritates and that an arrested lesion stays dark - that is the treatment working, not damage.
Saliva and diet. Suggest sugar-free gum or xylitol lozenges after meals to stimulate flow, frequent sips of water, and a saliva substitute if dryness is severe. Ask her GP to review the oxybutynin - that single change may do more than anything you apply. Swap the sipped cordial for water or plain milk and reduce the number of acid exposures rather than only the volume; if she will not give it up, keep it to mealtimes and finish with cheese or water.
What not to do. Do not add a fluoride mouthwash on top of a 5000 ppm paste as a substitute for fixing the routine, and do not let the plan become so complex she abandons it.
Review. Three months, with photographs and gentle probing of the active lesions.
3. She asks whether she should just have the teeth out. How do you structure the behaviour-change conversation, and what small changes would you negotiate first?
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Start with her agenda. Her question is the real conversation. Explore it: 'What's making you think that?' The answer will tell you whether it is cost, discomfort, frustration or fear - and each calls for a different response.
Use a structured, non-judgemental approach. Ask permission, then use motivational interviewing: open questions, affirmations, reflections and summaries. Ask her to rate importance and confidence out of 10, then ask what would move each up one point. That gives you her solution rather than yours.
Negotiate two or three changes. Candidates: brush at night as well as in the morning; spit, do not rinse; swap the sipper bottle for water between meals; chew sugar-free gum after meals. Let her choose which two. Agree if-then plans: 'If I finish lunch, then I chew gum'; 'If my mouth feels dry, then I sip water, not cordial.'
Address the practical barriers. Cost: spread appointments, prioritise the active lesions, and be clear about what is and is not funded. Dexterity: try toothbrush handle modifications or an electric brush if she can use one. Sensitivity: a soft brush and desensitising toothpaste for the exposed roots.
Health literacy and whanau. Use plain language, show her the lesions in a mirror or on an intraoral photo, and give one written sheet, not five. Ask whether she would like a family member at the next visit - for many older people the whanau are the ones who will support the routine.
Self-reflection. Notice your own assumptions about age, money and capacity. Ask rather than assume, and let her make the decision with you, including the decision to keep her teeth.