Severely Resorbed Mandible With Worn Complete Dentures and Xerostomia
A 72-year-old woman has worn complete maxillary and mandibular dentures for 8 years; she has been edentulous for 15 years. She complains that the mandibular denture rocks, traps food, and causes soreness under the left posterior ridge. The maxillary denture loses suction when she speaks. Examination shows a mandibular residual ridge 4 mm anteriorly and 2 mm posteriorly, with knife-edge and mobile tissue; prominent genial tubercles; a retracted tongue; and 8 mm of freeway space at rest. The existing posterior teeth are worn, and the mandibular denture base is overextended distally. She has controlled type 2 diabetes (HbA1c 7.2%), xerostomia from antihypertensive medication, and no history of bisphosphonate use. She wants “new teeth that stay” and is reluctant to have surgery.
1. Should the mandibular denture be relined/rebased or remade? Justify using the clinical findings, including vertical dimension and tissue health.
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This denture should be remade, not simply relined. A reline can improve adaptation to the tissue, but it cannot correct the worn posterior teeth, the lost vertical dimension, or the overextended distal border. The 8 mm freeway space at rest indicates the dentures are overclosed; normal freeway space is roughly 2–4 mm. If the teeth are worn and the mandible has been positioned too closed, the denture will also have poor stability and increased load on the anterior ridge.
My sequence would be:
- treat the sore area and identify any overextension or pressure spot;
- consider a temporary soft liner or tissue conditioner to rest the mucosa while a new prostheses is planned;
- verify that the increased vertical dimension is tolerated with a trial wax rim before tooth arrangement;
- remake both dentures, re-establishing an appropriate occlusal vertical dimension with about 3–4 mm freeway space and a retruded contact position that is reproducible.
A rebase would be a temporary measure at best and would not address the worn occlusal scheme.
2. Describe an impression and tooth-arrangement protocol for the severely resorbed mandible, and how xerostomia alters it.
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For a 2–4 mm knife-edge ridge with mobile tissue, I would use a custom tray and border molding, then a low-viscosity elastomeric or zinc oxide–eugenol impression with selective pressure. The goal is not maximal compression of the mobile tissue; it is a stable, repeatable tissue form. I would consider a neutral zone technique because the ridge is resorbed and the tongue is retracted. Using compound or silicone to record the neutral zone allows the teeth and polished surfaces to be placed where the tongue and cheek tolerate them, rather than simply over the crest.
Xerostomia changes the plan in several ways:
- impressions and try-ins may be more uncomfortable, so appointments should be shorter and tissues moistened;
- the denture base should be well polished and not overextended, because dry mucosa is more easily traumatized;
- the patient needs saliva substitutes or moisturizers, frequent water sips, and realistic expectations about retention;
- recall should be more frequent to catch pressure areas early.
I would also use a lingualized or balanced occlusal scheme to improve stability and reduce tipping forces.
3. Compare a conventional mandibular denture with a two-implant overdenture for this patient. What would you recommend, and what anatomical or medical factors influence the decision?
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A two-implant overdenture would predictably improve retention, stability, and chewing compared with a conventional denture, especially on a 2–4 mm ridge. But the recommendation depends on anatomy and risk. Her posterior ridge height of 2 mm may be inadequate for standard implants; she may need short implants, narrow implants, or grafting, and the genial tubercles and retracted tongue complicate the anterior lingual region. CBCT is required before recommending surgery.
Her controlled diabetes with HbA1c 7.2% is not an absolute contraindication, but it should be optimized and she should be told about infection and healing risk. She has no bisphosphonate history, which is favorable. Xerostomia increases plaque retention and may worsen peri-implant maintenance, so hygiene must be realistic.
My recommendation: offer a two-implant overdenture if CBCT shows adequate bone and she accepts surgery; otherwise remake a conventional denture using a neutral zone and consider a denture adhesive. I would not promise that implants will eliminate all sore spots, and I would not proceed without discussing maintenance and the possibility of grafting.