Clinical trial NCT06925438: "Computer-Guided vs Freehand Zygomatic Implant Placement
Official title: Comparison Between Computer Guided and Free Hand Placement of Zygomatic Implants (Clinical and Radiographic Evaluation)
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Dental Implants
Maxillary Diseases
Keywords: "Zygomatic implants"
"Atrophic maxilla rehabilitation"
"Guided implant surgery"
"Free-hand dental implantation"
"3D-printed surgical guides"
Lead sponsor: Al-Azhar University
Sponsor class: OTHER
First posted: 2025-04-13
Enrollment: 8
Sex: ALL
Minimum age (years): 40
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: This randomized trial compares computer-guided versus free-hand zygomatic implant placement in patients with atrophic maxillae or maxillary defects. Participants receive either 3D-navigated implants (using stereolithographic guides) or conventional free-hand placement. Primary outcomes measure accuracy through apical angular deviation (°), apical/coronal linear deviations (mm) relative to MSP/FHP/CP planes (CT-based), while secondary outcomes assess implant stability (ISQ) and complications (sinusitis/infection) over 6 months. The study evaluates whether guided surgery improves precision in complex maxillary rehabilitation.

Detailed description: "This study was retrospectively registered due to initial lack of awareness of prospective registration requirements. All procedures followed ethical guidelines (Approval #880/62), and results are reported transparently."

Study Design

A single-center, randomized controlled trial conducted at Al-Azhar University, comparing computer-guided versus free-hand zygomatic implant placement. Participants are allocated 1:1 to:

Group A (Free-hand): Implants placed using ZAGA classification with conventional surgical techniques.

Group B (Guided): Implants placed via 3D-printed bone-supported surgical templates (DICOM-based planning).

Interventions

Both Groups:

Pre-op: CT scans for zygomatic bone assessment.

Anesthesia: General anesthesia with local infiltration for hemostasis.

Surgical Protocol: Full-thickness flap, implant placement , two-stage healing.

Group B-Specific Steps:

Digital implant path planning (entrance/exit points).

Stereolithographic guide fabrication with metal sleeves.

Guide fixation with monocortical screws during surgery.

Rationale Zygomatic implants require high precision due to anatomical complexity. While free-hand placement depends on surgeon skill, computer guidance may reduce errors. This trial evaluates whether guided surgery improves accuracy (angular deviation) and reduces complications (sinusitis, infection).

Methodological Rigor Randomization: Block randomization via SPSS.

Blinding: Radiographic assessors blinded to group allocation.

Sample Size: 16 implants (8/group), powered to detect 3.73° mean angular deviation difference (α=0.05, β=0.10; based on Grecchi et al. 2022).

Ethical Compliance Approved by Al-Azhar University (Ref: 880/62).

Consent forms documented risks/benefits (e.g., sinus perforation, infection).

Eligibility criteria: Inclusion Criteria:

* Patients aged ≥40 years
* Atrophic maxillary ridge (Cawood \& Howell Class IV-VI)
* Maxillary defects due to trauma, tumor resection, or congenital conditions

Exclusion Criteria:

* Acute maxillary sinusitis
* Uncontrolled systemic diseases affecting osseointegration
* Pathological lesions in maxilla/zygoma
* Heavy smoking (\>20 cigarettes/day)

Primary outcomes:
measure: Angular deviation of zygomatic implants
timeFrame: Measured immediately post-operatively (Day 0)
measure: Apical linear deviation of zygomatic implants
timeFrame: Measured immediately post-operatively (Day 0)
measure: Coronal linear deviation of zygomatic implants
timeFrame: Measured immediately post-operatively (Day 0)
Secondary outcomes:
measure: Implant stability quotient (ISQ)
timeFrame: Immediately post-op and at 6 months
measure: Postoperative complication rates
timeFrame: Assessed at 1 week, 1 month, 3 months, and 6 months post-op
Other outcomes:
Locations:
city: Cairo
country: Egypt
facility: Faculty of Dental Medicine - Boys, Al-Azhar University
state: Cairo Governorate
city: Cairo
country: Egypt
facility: Oral and Maxillofacial Surgery Department, Faculty of Dental Medicine - Boys, Al-Azhar University
state: Cairo Governorate
Study officials:
affiliation: Al-Azhar University, faculty of dentistry ,Oral & Maxillofacial Surgery Dept
name: Bahaa El-Din Abd Raboo, phd
role: STUDY_DIRECTOR
affiliation: Al-Azhar University, faculty of dentistry, Oral & Maxillofacial Surgery Dept
name: Mohamed Abdel Akhar, PhD
role: STUDY_DIRECTOR
affiliation: Al-Azhar University, faculty of dentistry, Oral & Maxillofacial Surgery Dept
name: Abdelfattah Moawad, BDS, MSc
role: PRINCIPAL_INVESTIGATOR
References: