Mobile molars, a wedding and an HbA1c of 8.4%
Mr K, 47, attends for an emergency appointment complaining of a mobile upper right molar and bleeding when he brushes. He was diagnosed with type 2 diabetes 10 months ago; his latest HbA1c is 8.4% (64 mmol/mol) and he takes metformin 1 g twice daily. He smokes 15 cigarettes a day and has no intention of stopping. Full-mouth charting shows a plaque score of 68%, bleeding on probing of 62%, generalised probing depths of 5–7 mm, 7 mm on the mesiopalatal aspect of 16 and 26 with through-and-through furcation involvement, mobility II on both molars and mobility I on 11 and 21. Radiographs show 50–60% horizontal bone loss in the molar regions and no periapical radiolucencies. Apart from occasional food packing, 16 and 26 are asymptomatic. He has a family wedding in three weeks and wants 16, 26 and 'the loose front teeth' extracted now, followed by a bridge. He asks why his gums bleed more when he brushes harder.
1. State the periodontal diagnosis, including stage and grade, and justify how the medical and social history modifies it.
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Diagnosis: generalised periodontitis, currently unstable, with plaque-induced gingival inflammation.
Staging (severity and complexity): interdental clinical attachment loss is ≥5 mm and bone loss reaches the middle third of the roots, with through-and-through furcation involvement on 16 and 26 and mobility II. There is no reported tooth loss attributable to periodontitis, no bite collapse or drifting, and no need for complex full-mouth rehabilitation, so this is Stage III rather than Stage IV. I would confirm the history of tooth loss before finalising that, because five or more teeth lost to periodontitis would move the case to Stage IV.
Grading: worst-site bone loss divided by age is approximately 55/47 ≈ 1.2, which exceeds 1.0 and already indicates Grade C by the primary criterion. Two modifiers reinforce this: HbA1c of 8.4% (Grade C if ≥7.0%) and smoking of 15 cigarettes a day (Grade C if ≥10/day).
Why this matters clinically:
- Grade C sets a 3-monthly review interval, not an annual one.
- It reframes the conversation: the disease is progressing fast and two modifiable factors drive it.
- It predicts poorer healing and higher infection risk after surgery while glycaemia is uncontrolled.
- Mobility I on the incisors is most likely inflammatory plus occlusal trauma, not a reason for extraction; it usually improves after subgingival debridement.
2. He insists on having 16, 26 and the mobile incisors extracted within three weeks. How do you respond, and what is your treatment sequence over the next three months?
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Acknowledge the deadline, then separate the two requests.
The incisors: explain that mobility of 11 and 21 is largely due to inflammation and that removing sound teeth three weeks before a wedding is irreversible and unnecessary. Debridement plus oral hygiene instruction is likely to reduce mobility. Splinting is not a first step - splint only if mobility remains symptomatic after inflammation is controlled.
The molars: agree that through-and-through furcation involvement gives a guarded-to-poor prognosis, but the decision does not have to be made today. Extracting in an uncontrolled diabetic who smokes increases the risk of infection, dry socket and poor healing, and it does not treat the disease.
Sequence:
- Today - disclose and record full periodontal chart, oral hygiene instruction with a single technique, correct the brushing misconception (bleeding indicates inflammation, not over-brushing), and prescribe a chemotherapeutic adjunct.
- Full-mouth supra- and subgingival debridement under local anaesthesia, staged within two weeks.
- Written referral to his physician: request optimisation of glycaemic control toward HbA1c <7% before elective surgery, and confirm renal status and current medication.
- Very brief smoking cessation advice plus referral; document his response.
- Reassess at 6–8 weeks with full charting, bleeding scores and mobility.
- Only then decide on 16 and 26, plan any surgical periodontal therapy, and begin prosthetic planning once the periodontal status is stable. No bridge is designed on unstable abutments.
3. At the eight-week reassessment, which specific findings would justify extracting 16 and 26, and what non-extraction alternative would you still discuss?
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Findings that would justify extraction:
- Residual probing depths ≥6 mm with bleeding on probing at the furcation after debridement.
- Persisting Class III (through-and-through) furcation involvement that he cannot keep clean.
- Mobility that has not improved, or symptoms on function that he finds unacceptable.
- Continued plaque scores above about 20%, indicating he cannot maintain the site.
- Root caries, a new endodontic complication, or a furcation that cannot be accessed for maintenance.
If these are not present: he may choose to retain the teeth with three-monthly periodontal maintenance. That is a legitimate option and should be presented with an honest prognosis rather than as a failure. Note that the evidence for maintaining through-and-through furcations long-term is weak, and that any improvement depends on his self-care and on glycaemic control.
Alternatives worth discussing:
- Furcation plasty or odontoplasty to convert a Grade II/III into a maintainable anatomy, accepting some root exposure.
- Tunnel preparation in a lower molar - rarely appropriate now.
- Root resection of the involved root, only if the remaining roots are individually restorable and endodontically sound.
Record and communicate: the risk of caries and further attachment loss if the teeth are retained, and the prosthetic consequences of losing both molars (shortened dental arch versus implant or removable replacement). Whatever is decided, the decision is shared, documented, and revisited at each maintenance visit.