Stage and grade in a young smoker with diabetes
A 34-year-old man, a smoker of 15 cigarettes a day for 12 years, is referred with bleeding gums and drifting of the upper front teeth. He was diagnosed with type 2 diabetes two years ago; his most recent HbA1c is 7.9% and he takes metformin 1 g twice daily. There is generalised marginal erythema, with 5–7 mm probing depths on all first molars and incisors. The mesial of 16 shows 40% bone loss extending into the middle third of the root, a grade II buccal furcation and grade II mobility. Teeth 12 and 22 have 2 mm of recession, and there is no suppuration anywhere. His plaque score is 62% and he brushes once daily. He has never had periodontal treatment. His physician has been informed of the referral.
1. Classify his periodontitis under the 2017 classification, giving the reasoning for the stage and the grade rather than only the labels.
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Diagnosis: generalised periodontitis, Stage III, Grade C, currently stabilised only by his own inadequate plaque control.
Why Stage III. Severity is judged by the worst site, not the average. The mesial of 16 shows bone loss to the middle third of the root, which is Stage III territory; he also has a grade II furcation and grade II mobility, both Stage III complexity factors. Stage IV is excluded because there is no reported tooth loss from periodontitis, no masticatory dysfunction and no bite collapse.
Why Grade C. In the absence of direct evidence of progression, grade is estimated from the bone loss to age ratio: 40% divided by 34 years is about 1.18, which is above 1.0 and therefore Grade C. The two risk-factor modifiers confirm it rather than create it - smoking 15 cigarettes a day (≥10/day moves the grade towards C) and an HbA1c of 7.9% (≥7.0% in a diabetic does the same).
Why this matters clinically. A Stage III, Grade C patient is at high risk of further attachment loss, so he needs the full risk-factor programme - not just scaling - a shorter recall interval (3 months initially), and a realistic conversation that his prognosis depends at least as much on his smoking and glycaemia as on what I do with the curettes.
2. Outline phase I therapy and state exactly what you would do at the 6-week re-evaluation if 16 still has a 7-mm pocket, bleeding and grade II buccal furcation.
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Phase I (to be delivered over 2–3 visits):
- Personalised oral hygiene instruction: modified Bass technique and correct-sized interdental brushes, since his plaque score is 62% and he brushes once a day.
- Supra- and subgingival instrumentation, quadrant by quadrant under local anaesthesia, including the furcation.
- Smoking cessation advice with referral to a cessation service - this is a treatment, not a lecture.
- Written request to his physician for tighter glycaemic control, with his consent.
- No extractions are indicated; no splinting of mobile teeth at this stage.
- Re-evaluate at 6 weeks, not later, with a full probing chart.
At 6 weeks with 16 unchanged:
- Repeat subgingival instrumentation of 16 under local anaesthesia and reinforce furcation-specific cleaning; re-evaluate in a further 6–8 weeks. Residual calculus and poor plaque control are the commonest reasons a furcation fails to respond.
- If bleeding and 7 mm persist, this is a non-responding site in a smoker. Options are surgical access with a regenerative approach for the buccal class II furcation, or root resection/hemisection - but neither is predictable while he smokes. I would make smoking cessation a precondition for surgery rather than operate on a smoker with a 62% plaque score.
- Extraction is not indicated: mobility II with a class II furcation can be maintained for years with good hygiene, and 16 is a key molar.
3. Which two factors will most influence his long-term prognosis, and how do you address both within a single 20-minute appointment?
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The two factors are smoking and glycaemic control. Both are established risk factors for progression and both blunt the response to treatment; neither is fixed by scaling.
Smoking (10 minutes):
- Ask permission before advising; state the link plainly - smokers lose more attachment and respond less well to both non-surgical and surgical therapy.
- Quantify: 15 a day for 12 years. Offer a quit date within two weeks, and refer to a cessation service for pharmacotherapy (nicotine replacement or varenicline) plus behavioural support.
- Agree a realistic target and record it. Even reduction helps, but cessation is the aim.
Glycaemia (5 minutes):
- Explain the two-way relationship: periodontal inflammation worsens glycaemic control, and poor control worsens periodontitis.
- With his consent, write to his physician asking for review of his regimen, noting the HbA1c of 7.9% and the periodontal diagnosis, and request the value at his next review.
The remaining 5 minutes:
- Show him his own probing chart and bleeding scores so that the numbers are concrete.
- Agree the review interval (3 months, not 6) and book it before he leaves.
- State the outcome honestly: with cessation and control of his HbA1c, most of his teeth are retainable; without them, Stage III Grade C disease will progress despite good mechanical therapy.