Marginal bone loss around implants retaining hinging mandibular overdentures, at 4-, 8- and 12-years follow-up

Area of Science:

• Dental Implantology
• Prosthodontics
• Periodontology

Background:

• Screw-shaped machined surface commercially pure (c.p.) titanium implants are used for hinging mandibular overdentures.
• Long-term maintenance of alveolar bone height is crucial for implant success.

Purpose of the Study:

• To investigate the influence of occlusal factors, oral hygiene, gender, and age on long-term alveolar bone height maintenance around c.p. titanium implants.
• To evaluate the long-term success rate and marginal bone loss associated with these implants in retaining mandibular overdentures.

Main Methods:

• A retrospective study with a 12-year follow-up of 158 patients treated with implant-retained overdentures.
• Intra-oral radiographs were taken at baseline and at 4, 8, and 12 years post-treatment.
• Marginal bone height was measured using digital calipers, and clinical data were recorded.

Main Results:

• Only the factor of time demonstrated a significant influence on marginal bone loss.
• Patient age, gender, oral hygiene, occlusal factors, and implant location did not significantly affect bone loss.
• A high cumulative success rate of 97.2% was observed after 12 years.

Conclusions:

• The long-term use of screw-shaped machined surface c.p. titanium implants for mandibular overdentures shows a high success rate.
• Limited marginal bone loss, averaging 1.7 mm over 12 years, supports the efficacy of this treatment modality.
• Time is the primary factor influencing bone loss, with other patient-specific and prosthetic factors having no significant impact.