Single Implant Crowns Supported by Narrow or Standard Diameter Implants in Molar Sites
Single Implant Crowns Supported by Narrow or Standard Diameter Implants in Molar Sites: a Randomized Controlled Trial
Mohammed Bin Rashid University of Medicine and Health Sciences
40 participants
Oct 1, 2025
INTERVENTIONAL
Conditions
Summary
Standard dental implants require sufficient bone and spacing, which may not be available in all patients. To address these limitations, narrow diameter implants (≤3.5 mm) have been introduced as a less invasive alternative, especially useful for medically compromised patients or those avoiding bone grafts. However, narrow implants made of pure titanium have shown long-term biological and technical concerns. The introduction of titanium-zirconium (TiZr) alloy has improved mechanical strength, and several studies have demonstrated favorable outcomes with narrow TiZr implants. Yet, evidence remains limited regarding their exclusive use in high-load posterior (molar) regions. Prior studies report conflicting failure rates, potentially linked to prosthetic design and occlusal forces, but lack quantitative analysis of bite forces or prosthetic angles. Emergence angle, prosthetic platform width, and implant-abutment connection may all influence implant stability and peri-implant tissue health. A newly introduced TorcFit™ connection may offer better stress distribution and torque resistance, but its clinical relevance-especially in narrow implants used for molars-remains untested.
Eligibility
Inclusion Criteria7
- Aged ≥ 18 years.
- Require replacement of single missing molar tooth with dental implant in fully healed sites.
- Controlled oral hygiene (full-mouth plaque and bleeding scores ≤ 25% at baseline).
- Intact adjacent teeth and opposing dentition.
- Fully healed sites (≥ 6 months) with limited bone availability in the horizontal bucco-lingual dimension (residual bone width of ≤ 6 mm) and minimal height of 8 mm.
- Good compliance and commitment to attend follow-up review appointments.
- Willing to provide informed consent.
Exclusion Criteria9
- Localized/generalized periodontitis.
- Any medical condition that may contraindicate implant treatment (Bornstein et al., 2009).
- Bone metabolic disease and/or taking medications that affect bone metabolism.
- Long term use of non-steroidal anti-inflammatory medications.
- History of malignancy, radiotherapy or chemotherapy.
- Pregnant or lactating women.
- Smokers.
- Severe bruxism or parafunctional habits.
- Large occlusal discrepancies.
Interested in this trial?
Get notified about updates and connect with the research team.
Interventions
Replacement of a missing molar tooth with a narrow dental implant
Replacement of a missing molar tooth with a standard dental implant
Locations(1)
View Full Details on ClinicalTrials.gov
For the most up-to-date information, visit the official listing.
NCT07073196