Implant-retained overdenture request in an older woman on long-term oral alendronate
A 74-year-old woman attends for a routine review of her complete dentures, which were made fourteen years ago. She has worn them every day and night since. The lower denture is loose, she avoids eating in public, and she has developed angular cheilitis and generalised palatal erythema under the upper denture. She has osteoporosis diagnosed eight years ago and has taken alendronate 70 mg weekly for the past six years, together with calcium and vitamin D; she takes no steroids and has never had radiotherapy or chemotherapy. She is a non-smoker and her GP recently described her bone density as stable. Her mandibular ridge is severely resorbed, with about 8 mm of anterior bone height on the panoramic radiograph and less than 5 mm posteriorly. She has read about implants and asks whether two implants could hold her lower denture. She is otherwise fit, lives independently, and can pay for treatment privately.
1. Is she a suitable candidate for a mandibular two-implant overdenture? Weigh the benefits against the risks and set out what you would tell her.
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Benefits are real and well evidenced Two implants with a stud or locator attachment in the anterior mandible substantially improve retention, chewing ability, confidence and quality of life compared with a conventional lower denture, and the anterior mandible is usually the most favourable site for bone volume and bone density. Her complaint - a loose lower denture and social avoidance - is exactly what this treatment addresses, and no conventional denture will fully solve it on a ridge with 8 mm anterior height.
Risks and modifiers
- Medication-related osteonecrosis of the jaw. Oral alendronate at low dose for osteoporosis carries a low absolute risk (well under 0.1% in most series), but risk rises with duration, and six years exceeds the four-year point at which many guidelines suggest reviewing the need for continuation. The risk is not zero and she must understand that.
- Implant failure and difficulty of salvage in a resorbed mandible.
- Her age and dexterity for attachment hygiene; locator housings collect debris and require cleaning.
- Unrealistic expectations if the upper denture remains unstable - the upper has visible stomatitis and is 14 years old.
What I would tell her That the treatment is reasonable and not contraindicated, that the chance of the implants failing is low but the chance of a serious jaw-healing problem is small yet real, that a new upper denture is needed regardless, and that a conventional new lower denture with a soft lining is a legitimate alternative that she should consider before committing.
2. What would you do at this first visit, and what investigations and consultations would you set up before any surgical decision?
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Today - treat the soft tissue problem and gather information
- Diagnose the palatal erythema as almost certainly denture stomatitis, and the angular cheilitis as candidal and/or associated with reduced vertical dimension. Take a swab only if it fails to respond.
- Ask her to leave both dentures out at night, clean them mechanically and soak them, and prescribe a topical antifungal (for example miconazole gel or nystatin), checking for interaction with any medicines she takes; consider chlorhexidine as an adjunct.
- Check fasting glucose or HbA1c - undiagnosed or poorly controlled diabetes both predisposes to stomatitis and affects implant healing. Ask about dry mouth and medications causing it.
- Assess the dentures: fit, extension, occlusion, vertical dimension. Fourteen-year-old dentures on a resorbed ridge will have lost both retention and occlusal balance.
- Photographs, and study casts or an intraoral scan to record the current situation.
Investigations A current panoramic radiograph (hers may be old) to measure bone height and identify the mental foramina, plus a cone-beam CT if implant planning proceeds, to assess width and the incisive canal-free anterior mandible.
Consultation A letter to her GP: confirm the exact antiresorptive, the start date, any previous or planned dental extractions, and ask whether there is any reason she must continue alendronate - a review of continuing beyond five years is a decision for the physician, not for me. I would also ask about renal function and calcium/vitamin D status.
Only after the soft tissues have settled, her expectations are discussed and the physician's view is available would I plan surgery.
3. She elects to proceed. What would your consent discussion and surgical plan cover if she later also needed an extraction of a retained root in the anterior mandible?
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Consent discussion
- The diagnosis and the alternatives: new conventional dentures, implant-retained overdenture, or no treatment, with the realistic difference in function and the cost and maintenance burden of each.
- Specific complications: pain, swelling, bruising, bleeding, infection, temporary or permanent altered sensation in the lip and chin, implant failure and need for replacement, difficulty cleaning attachments, and fracture of the severely resorbed mandible.
- Medication-related osteonecrosis of the jaw in plain terms: what it is, that her risk is low but not absent, that it rises with duration of alendronate and with trauma, and what she should report. Document this explicitly.
- The possibility of needing a bone graft or a change of plan if the CBCT shows insufficient width.
- Written information and a cooling-off interval before surgery.
Surgical plan for the implants Atraumatic technique under local anaesthesia with adrenaline, limited flap reflection, copious irrigation and primary closure, short implants placed in the anterior mandible between the mental foramina, avoiding the sublingual artery territory, with a healing period before loading.
If a retained root later needs removal I would treat that as a separate higher-risk procedure: review the medication status and any physician advice first, consider whether removal is truly necessary or whether it can be managed by adjustment of the denture base, plan a minimally traumatic approach with primary closure, give appropriate antibiotic cover according to local guidance, and warn her that the necrosis risk is concentrated around extraction sites. If she is still taking alendronate long term, I would discuss timing with her physician rather than institute a 'drug holiday' on my own initiative, since the evidence that a holiday reduces risk is weak.