Passive Fit and Time Efficiency in All On-X Implants Protocols Using Photogrammetry, Splinted Scan Bodies, and Conventional Impression Technique

For edentulous patients undergoing full-arch rehabilitation, the All-on-X treatment approach has proven to be a very successful option, providing enhanced function, aesthetics, and patient satisfaction. Achieving passive fit, which reduces mechanical stress on implants and prosthetic components and reduces the possibility of problems such screw loosening, fracture, or marginal bone loss, is crucial to the long-term effectiveness of implant-supported prostheses. Passive fit has traditionally been evaluated after prostheses are fabricated using traditional open-tray impression techniques, which are regarded as the gold standard because of their great precision and dependability. These approaches, however, are challenging, technique-specific, and susceptible to human mistake or material deformation. Other methods include digital intraoral scanning with splinted scan bodies and photogrammetry have become more appreciated due to the quick development of digital dentistry. Potential advantages of these digital workflows include quicker digital data transfer to the lab, less chairside time, and improved patient comfort. In the context of the All-on-X procedure, there is still no clinical data comparing the accuracy especially passive fit and time efficiency of these more recent methods with traditional impressions, despite these benefits. Thus, the purpose of this study is to compare the time efficiency and passive fit of three impression techniques: traditional open-tray impressions, digital intraoral scanning with splinted scan bodies, and photogrammetry. The findings will provide clinicians with evidence-based insights into whether digital alternatives can match or surpass traditional techniques in terms of accuracy and workflow efficiency, ultimately supporting the transition toward more modern, streamlined protocols in implant prosthodontics.

Inclusion criteria

Adults aged 45-65 years.

Fully edentulous or partially edentulous maxilla requiring full-arch rehabilitation.

Sufficient maxillary bone volume to support at least four implants according to the All-on-X protocol.

Systemically healthy patients with no contraindications to dental implant surgery (ASA I-II classification).

Demonstrated ability to maintain adequate oral hygiene.

Willingness to participate in the study and comply with follow-up visits and required maintenance protocols.

Patients seeking a fixed, implant-supported prosthesis for the maxilla due to missing teeth and inability to use removable prostheses effectively.

Acceptable radiographic findings with no signs of pathology, infection, or significant anatomical limitations.

Exclusion criteria

Uncontrolled systemic diseases (e.g., uncontrolled diabetes, osteoporosis, immunosuppressive disorders)

History of radiation therapy to the head and neck region

Active periodontal disease or untreated caries

Maxillary cysts, tumors, or pathologies

Poor oral hygiene or inability to maintain postoperative care

Insufficient bone volume for All-on-X without extensive grafting

Maxillary sinus pathology or oroantral fistula

Psychiatric illness or cognitive impairment affecting compliance

Bruxism or parafunctional habits

Pregnant or lactating women

History of implant failure or titanium allergy

Use of bisphosphonates or antiresorptive medications

Heavy smoking (>10 cigarettes/day)

Inability or unwillingness to attend follow-up visits

Diagnosed or symptomatic temporomandibular joint disorders (pain, clicking, locking, limited opening)