Titanium Zirconium (TiZr) Mini Implants

Is the Stabilization of a Mandibular Overdenture Employing Four Novel One-piece Immediately Loaded TiZr Implants With Miniaturized Stud-type Attachments a Feasible Alternative to Two Two-piece Early Loaded Tissue-level Implants With Regular Stud-type Attachments?

H0: "Within the first year post-placement, four interforaminally placed, immediately loaded 2.4 mm narrow-diameter one-piece TiZr implants with miniaturized stud-type attachments show improved patient-reported outcome measures (PROMS) compared to two interforaminally placed, early loaded, TiZr two-piece implants with stud-type attachments to retain a mandibular overdenture."The specific aim is to compare both treatment alternatives to evaluate which one may be recommended for elderly edentulous patients.

Inclusion Criteria:

• At patient level:

  • Written informed consent
  • Age ≥ 18 years
  • Sufficient complete dentures (Marxkors and Ferger, 1989) not older than 1 year
  • Patient is unsatisfied with mandibular denture to the degree that he/she seeks treatment

• At site level:

  • Healed edentulous mandible (minimum 8 weeks since last extraction)
  • Minimal ridge dimensions 5.5 mm (width) by 12 mm (height) in the anterior (interforaminal) area, allowing the placement of 3.3 (endosseous diameter) by 10 mm (length) implants
  • Opposing dentition: complete denture on a edentulous maxilla
  • Physical status (PS) 1 and 2 (American Society of Anesthesiologists)

Exclusion Criteria:

• At patient level

  • Any physical or mental disorder that would interfere with the ability to perform adequate oral hygiene or the capability of providing written informed consent and compliance to the protocol
  • Any disorder that would interfere with wound healing or represent a contraindication for oral surgery such as, but not limited to, uncontrolled diabetes or conditions resulting in or requiring immunosuppression, radiation, chemotherapy, frequent use of antibiotics or antiresorptive medication such as bisphosphonates
  • Pregnancy or lactation
  • Heavy smoking habit with > 20 cig/d
  • Severe bruxism or clenching habits, present oro-facial pain

• At site level:

  • Ridge defects requiring staged bone augmentation procedures (simultaneous Guided Bone Regeneration (GBR) within the ridge contour allowed)