Implant-Supported Crown in a Patient with Treated Periodontitis and Bruxism
A 62-year-old woman requests replacement of a missing lower left first molar. She has a history of stage III grade C periodontitis treated 4 years ago, with current plaque scores around 35 percent and bleeding on probing at 25 percent of sites. She has well-controlled type 2 diabetes with HbA1c 7.1 percent, smokes 10 cigarettes daily, and grinds her teeth at night. Bone height at the site is adequate for a 10 mm implant but the interdental space is 7 mm. She wears a soft night guard. She asks for a single implant crown and wants it finished before a family wedding in 10 weeks.
1. Assess her risk profile and explain whether you would proceed now, and what you would do first.
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Her risk profile is elevated on several axes. Treated periodontitis with residual bleeding at 25 percent and plaque at 35 percent indicates unstable periodontal control, and a history of grade C disease predicts progression and peri-implant risk. Smoking 10 daily and HbA1c 7.1 percent both impair healing and increase infection and implant failure risk. Bruxism increases mechanical overload, especially with a single molar implant. The 10-week deadline is unrealistic for a predictable outcome. I would not place the implant now. First, reinforce oral hygiene with a hygienist, target bleeding below 15 to 20 percent, offer smoking cessation support, and confirm diabetes control with her physician. I would explain that prosthodontic planning must follow periodontal stabilisation and that rushing to meet the wedding risks early failure and peri-implant disease.
2. What prosthetic and occlusal design decisions would you make, and how do you manage the 7 mm space?
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With 7 mm interdental space, a standard molar crown may be too wide and create unfavourable cantilevers and hygiene problems. Options are a narrower premolar-sized crown on a reduced-diameter implant, or a cantilevered or fixed partial denture design; a short-span fixed dental prosthesis may be more appropriate than a single implant in a bruxist. If an implant is used, choose a moderately sized platform, ensure adequate keratinised tissue, and design a screw-retained crown with a shallow occlusal scheme. For bruxism, provide a hard occlusal splint, avoid heavy excursive contacts, and consider a mutually protected occlusion with light centric contacts. Discuss maintenance with regular peri-implant probing and radiographs. The wedding can be met with a provisional removable prosthesis while the definitive plan is staged.