Long-Term Clinical and Radiographic Outcomes Following Freehand and Guided Dental Implant Placement: A Randomized Controlled Trial Follow-Up (SMART-ACCURACY)

This study is a long-term clinical follow-up of a previously conducted randomized trial comparing different levels of surgical guidance in dental implant placement. The follow-up phase aims to evaluate peri-implant clinical and radiographic outcomes over an extended observation period of up to 67 months. Clinical parameters and marginal bone level changes are assessed to determine whether the accuracy benefits observed at implant placement translate into favorable long-term biological outcomes.

Study Overview

• Status: Completed
• Conditions: Dental Implant; Edentulism; Navigation
• Intervention / Treatment: Procedure: dental implant placement

Detailed Description

The original clinical trial was designed to compare the accuracy of freehand and guided dental implant placement using different levels of surgical navigation. A total of 101 partially edentulous volunteers were enrolled and randomly assigned to one of four surgical protocols: freehand implantation, pilot-guided implantation, partially guided implantation, or fully guided implantation. Implant placement accuracy was evaluated by comparing the digitally planned implant positions with the actual postoperative implant positions using three-dimensional computerized analysis.

The present investigation represents an extended follow-up of this cohort, conducted to assess the long-term clinical performance of the placed implants. Follow-up evaluations began in February 2019 and continued until September 2024, resulting in a total observation period of up to 67 months. The extended duration exceeded the originally planned follow-up due to logistical interruptions related to the COVID-19 pandemic.

Clinical follow-up focused on peri-implant tissue health and marginal bone stability. Peri-implant probing depth was recorded as a clinical indicator of soft tissue conditions around the implants after delivery of the definitive prosthetic restorations. Measurements were performed at standardized sites around each implant, and mean probing depth values were calculated for longitudinal analysis.

Radiographic follow-up was performed using standardized bitewing radiographs to assess marginal bone levels. Marginal bone level was defined as the vertical distance between the implant platform and the alveolar crest, measured both mesially and distally. Because radiographic projection angles could not be fully standardized across all visits, individual calibration was performed for each implant using the known implant neck diameter provided by the manufacturer. This allowed reliable two-dimensional measurements despite variations in radiographic geometry.

The primary objective of this follow-up study is to describe long-term peri-implant clinical and radiographic outcomes following implant placement performed with varying levels of surgical guidance. Secondary objectives include assessing the stability of marginal bone levels over time and identifying potential differences between surgical protocols in long-term biological performance.

• Study Type: Interventional
• Enrollment (Actual): 96
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Hungary
  • Csongrád megye
    • Szeged, Csongrád megye, Hungary, 6724
      • Smile Dent

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• • Age between 18 and 75 years

  • Partial edentulism in the maxilla or mandible involving 1-6 missing teeth, with no more than three adjacent missing teeth
  • Clinical conditions suitable for implant placement as assessed by the investigator or principal investigator (adequate bone and soft tissue conditions and acceptable occlusion)
  • Ability to communicate effectively with the investigators and willingness to comply with study procedures
  • Provision of written informed consent

Exclusion Criteria:

• • Pregnancy or breastfeeding

  • Women of childbearing potential without adequate contraception (for radiological safety reasons)
  • Conditions preventing safe intraoral manipulation (e.g., limited mouth opening, pronounced gag reflex)
  • Current or previous bisphosphonate therapy
  • History of radiotherapy involving the maxilla or mandible
  • International normalized ratio (INR) > 2.5
  • Known HIV, hepatitis B, or hepatitis C infection
  • Known allergy to any component of the implant or surgical guide system
  • Poor oral hygiene
  • Substance abuse
  • Smoking
  • Untreated periodontal disease
  • Any systemic disease or condition judged by the principal investigator to pose an unacceptable risk to the participant or to compromise study completion

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: free hand; free hand implant placement	Procedure: dental implant placement; placing dental implants
Experimental: pilot; pilot static guided implant placement	Procedure: dental implant placement; placing dental implants
Experimental: partial; partial static guided implant placement	Procedure: dental implant placement; placing dental implants
Experimental: full; full static guided implant placement	Procedure: dental implant placement; placing dental implants

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Implant Survival	Long-term survival of dental implants placed in the four study arms defined in the IMP SMART 002 trial, evaluated as a direct temporal extension of the IMP SMART 002 protocol (OGYÉI approval number 2224-4/2019). Implant survival is defined as the implant remaining in situ and functional without removal.	Up to 67 months post-implant placement

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Long-Term Tolerability and Safety	Assessment of the long-term tolerability and safety of the implanted dental implants based on the occurrence of adverse events and complications.	Up to 67 months post-implant placement
Number of events of prosthodontic complications	Prosthodontic complications of the screw-retained implant-supported veneered zirconia prostheses in both arches were monitored and recorded throughout the 67-month follow-up period. Complications were calculated based on the occurrence of the following events: loss of access-hole cover, framework fracture, veneering ceramic fracture, prosthetic tooth fracture, abutment screw loosening, abutment screw fracture, prosthesis screw loosening, and prosthesis screw fracture.	From prosthetic delivery up to 67 months of follow-up
Oral Health-Related Quality of Life Assessed by the OHIP-14 Questionnaire	Patient-reported oral health-related quality of life assessed longitudinally using the validated Hungarian version of the Oral Health Impact Profile-14 (OHIP-14) questionnaire. The OHIP-14 evaluates the impact of dental implants and implant-supported prosthetic restorations on functional, physical, psychological, and social aspects of daily life. Measurement Tool: OHIP-14 questionnaire (14 items). Unit of Measure: Total OHIP-14 score (sum score ranging from 0 to 56), where higher scores indicate poorer oral health-related quality of life. Method of Assessment: For each visit, individual item scores (5-point Likert scale: 0 = never to 4 = very often) are summed to calculate a total OHIP-14 score. Mean total scores are calculated across the study population at each visit to evaluate changes in oral health-related quality of life over time.	Up to 67 months post-implant placement
Marginal Bone Loss	Long-term assessment of peri-implant marginal bone changes using standardized radiographic evaluation. Unit of Measure: Millimeters (mm)	From prosthetic delivery up to 67 months of follow-up
Probing Depth	Long-term assessment of peri-implant soft tissue health by measuring probing depth around dental implants. Unit of Measure: Millimeters (mm)	From prosthetic delivery up to 67 months of follow-up
Gingival Index	Long-term assessment of peri-implant gingival inflammation using the Gingival Index score. Unit of Measure: Score (Units on a Scale)	From prosthetic delivery up to 67 months of follow-up
Plaque Index	Long-term assessment of oral hygiene status around dental implants using the Plaque Index score.	From prosthetic delivery up to 67 months of follow-up
Width of Keratinized Gingiva	Long-term assessment of peri-implant soft tissue characteristics by measuring the width of keratinized gingiva. Unit of Measure: Millimeters (mm)	From prosthetic delivery up to 67 months of follow-up

Collaborators and Investigators

• Sponsor: SmileDent Kft.

Study record dates

Study Major Dates

• Study Start (Actual): February 11, 2019
• Primary Completion (Actual): February 11, 2024
• Study Completion (Actual): September 30, 2024

Study Registration Dates

• First Submitted: January 2, 2026
• First Submitted That Met QC Criteria: January 20, 2026
• First Posted (Actual): January 28, 2026

Study Record Updates

• Last Update Posted (Actual): January 28, 2026
• Last Update Submitted That Met QC Criteria: January 20, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: long-term follow-up; dental implant; static guidance accuracy
• Other Study ID Numbers: IMP SMART 2224-4/2019

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No