Dental Implants, Edentulous Jaw, Passive Fit
Conditions
Keywords
Passive fit, Implant-supported framework, Digital impression, Full-arch implant prosthesis, Crossover study
Brief summary
This randomized crossover clinical trial compares the passivity of fit of complete-arch mandibular implant-supported frameworks fabricated using three impression techniques: a non-calibrated splinted digital scan body system (IO-Connect), a Reverse Scan Body (RSB) digital impression technique, and a conventional splinted open-tray impression technique. Eight completely edentulous patients each receiving four mandibular implants will be included. Passivity of fit will be evaluated clinically using the Sheffield one-screw test and radiographically using intraoral periapical radiographs obtained with the parallel technique.
Detailed description
Full-arch implant-supported fixed prostheses require a high degree of passive fit to avoid mechanical and biological complications. While digital impression workflows are increasingly used as alternatives to conventional splinted impressions, evidence directly comparing their clinical accuracy for complete-arch implant frameworks remains limited, particularly for the IO-Connect non-calibrated splinting system and the Reverse Scan Body technique. Eight completely edentulous patients with at least four mandibular implants will be enrolled. Using a crossover design, each patient will undergo all three impression techniques: Group I (IO-Connect splinted scan bodies), Group II (Reverse Scan Body technique), and Group III (conventional splinted open-tray impression with polyvinyl siloxane and Type IV stone casts). For each technique, a corresponding implant-supported framework will be fabricated and evaluated for passivity of fit using the Sheffield one-screw test and periapical radiographs taken with a paralleling device to assess microgaps at the implant-framework interface.
Interventions
PROCEDUREIO-Connect Digital Impression
Digital impression of the mandibular arch obtained using IO-Connect non-calibrated splinted scan bodies to fabricate the implant-supported framework for Group I.
PROCEDUREReverse Scan Body Digital Impression
Digital impression obtained using the Reverse Scan Body (RSB) technique, involving extraoral scanning of scan bodies and superimposition with intraoral tissue scans, to fabricate the implant-supported framework for Group II.
PROCEDUREConventional Splinted Impression
Conventional splinted open-tray impression using polyvinyl siloxane material and Type IV dental stone to fabricate the implant-supported framework for Group III.
Sponsors
Mansoura University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Each patient will sequentially receive all three impression techniques (IO-Connect, Reverse Scan Body, and conventional splinted impression) for framework fabrication and passive fit evaluation.
Eligibility
Sex/Gender
ALL
Age
35 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* Completely edentulous patients requiring full-arch implant-supported fixed prosthesis * Age 35-70 years * Adequate mandibular bone to place at least four implants without major grafting * Ability to undergo digital scanning and radiographic evaluation * Signed informed consent
Exclusion criteria
* Systemic conditions affecting healing (uncontrolled diabetes, immunosuppression) * History of head/neck radiotherapy or bisphosphonate therapy * Active oral infection or severe bruxism * Strong gag reflex preventing accurate scanning * Poor compliance or unwillingness to attend follow-up visits
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Passive Fit Assessed by Sheffield One-Screw Test | The evaluation of passive fit by Sheffield one-screw test will be done 3 months after implant placement (3M-IP), at framework try-in for each of the three impression techniques. | The framework was seated on all implants and a single distal screw was fully tightened; remaining screw sites were examined visually and tactilely for lifting, rocking, or gaps as an indicator of passive fit. |
| Passive Fit Assessed by Periapical Radiographs | The evaluation of passive fit by periapical radiographs will be done 3 months after implant placement, at framework try-in for each of the three impression techniques. | Intraoral periapical radiographs were obtained at each implant site using a paralleling device and evaluated for microgaps at the implant-framework interface. |
Countries
Egypt
Contacts
CONTACTAhmed H Hazem Elsayed Helmi Atwa, BDS
STUDY_CHAIRFatma A El-Waseef, PhD
Mansoura University
Outcome results
None listed