Stage III periodontitis in a smoker with a through-and-through furcation
A 46-year-old woman attends for periodontal assessment. She smokes 15 cigarettes daily, has a BMI of 31 and an HbA1c of 6.9% on metformin, and brushes once daily without interdental cleaning. Full-mouth charting shows generalised plaque and calculus, bleeding on probing at 68% of sites, and pocketing of 6–9 mm on all first and second molars. The mandibular right first molar (46) has 9 mm pockets buccally and lingually with through-and-through furcation involvement, grade II mobility and 60% bone loss; the mandibular left first molar (36) has a buccal class II furcation, 7 mm pockets and a 3 mm vertical defect mesially. The maxillary central incisors have 5 mm pockets, 30% bone loss and no mobility. Radiographs confirm horizontal bone loss of 40–60%. She says she is not ready to quit smoking but will "cut down", and asks whether she will lose her molars.
1. Assign a stage and grade using the data and justify each element.
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Stage III. Interdental clinical attachment loss is at least 5 mm, radiographic bone loss extends into the middle third of the roots, and there is a class II furcation and a 3 mm vertical defect. It is not Stage IV because there are no teeth lost to periodontitis, no need for complex rehabilitation, no severe ridge defect and no masticatory dysfunction yet; those would be reassessed after treatment.
Grade C. The primary criterion is radiographic bone loss divided by age: 60% at age 46 gives 1.3, which exceeds 1.0 and places her in Grade C regardless of other features. Direct evidence of rapid progression is not available because there are no previous radiographs. The grade modifiers support this: smoking 15 cigarettes daily is a Grade C modifier, and diabetes with an HbA1c of 6.9% adds a further modifier of risk. It is worth noting that an HbA1c below 7.0% is not the dominant factor here: smoking and the bone-loss-to-age ratio drive the grade.
This staging and grading is a provisional risk assessment that must be repeated after initial therapy; if she stops smoking and responds well, the grade still records her historical risk but the prognosis improves. Record the bleeding score, plaque score, probing depths and recession as the baseline against which the re-evaluation at eight to twelve weeks will be compared. Explain to her that grade indicates the rate of progression and her susceptibility, not a prediction that a specific tooth will be lost.
2. Plan the first two phases of treatment and justify which adjuncts you would and would not use.
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Step 1 - risk and behaviour control. Brief smoking-cessation intervention with referral to a cessation service, recorded in the notes. Coordinate with her physician over glycaemic and weight management. Oral hygiene instruction with an interdental brush sized to each space, and a demonstration of correct technique. Professional mechanical plaque removal, calculus removal, and extraction of any hopeless tooth. Reassess motivation and plaque control at four to six weeks, because everything that follows depends on it.
Step 2 - subgingival instrumentation. Full-mouth or quadrant-wise scaling and root surface debridement under local anaesthesia, with adequate time and sharpened instruments. Re-evaluate at eight to twelve weeks with a full periodontal chart.
Adjuncts. Systemic amoxicillin 500 mg plus metronidazole 400 mg three times daily for seven days is justified in selected Stage III cases as an adjunct to thorough debridement, not as a substitute for it, and it should be considered only after step 2, when residual deep pockets persist and hygiene is good. Local delivery agents are not first-line here. Lasers are not recommended for pocket reduction; the evidence does not support them over conventional debridement.
What matters most is smoking cessation. Continuing to smoke substantially blunts the response to treatment, and it is fair to tell her that "cutting down" has limited periodontal benefit compared with stopping. Antibiotics given to a continuing smoker with poor plaque control are likely to be wasted.
3. What would you do with 46 and 36, and how would you counsel her about the molars and about replacing them?
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46. Nine-millimetre pockets buccally and lingually, through-and-through furcation involvement, grade II mobility and 60% bone loss give a poor to hopeless prognosis. Retaining it risks recurrent abscess, further bone loss and loss of the site for a future implant or bridge. Extraction at the appropriate stage is usually the right decision, and it should be presented as a planned decision rather than a failure. It does not need to be extracted on the first visit; it can be removed during step 2, but she should understand why.
36. A buccal class II furcation with a 3 mm mesial vertical defect is a potential candidate for regenerative surgery, with guided tissue regeneration with or without a bone graft, if the pocket remains 6 mm or more after step 2, if she is compliant with hygiene, and if she stops smoking. If she continues to smoke and plaque control remains poor, regenerative surgery is likely to fail and is not justified; maintenance or extraction are then the honest options. Reassess after step 2 rather than committing now.
Counselling. Explain that the molars are the teeth most severely affected, that her response depends heavily on smoking and hygiene, and that she will need three-monthly maintenance for life. Explain that replacing 46 with an implant in a smoker with a history of periodontitis carries an increased risk of peri-implantitis and mucositis, and that implants should be planned only after risk control and with the same maintenance commitment. There is no guarantee that 36 can be saved; the honest position is a guarded prognosis with a defined review point.