Guided Pterygoid Implant

Comparing Accuracy of Pterygoid Implants Placement Using Computer-guided Surgical Templates Versus Free Hand Technique

Introduction & Background Alveolar ridge resorption after tooth extraction leads to significant bone loss, complicating prosthetic rehabilitation. Traditional bone grafting methods, though effective, involve long healing times and risks. Pterygoid implants offer a graft-free alternative by engaging dense bone structures like the pterygoid process. However, their placement is technically challenging due to limited visibility and proximity to critical structures. Computer-guided surgery may improve accuracy and reduce complications compared to freehand techniques.

Research Question Does computer-guided surgery enhance the accuracy of pterygoid implant placement in atrophic maxillae compared to freehand techniques? Aim To compare the accuracy of computer-generated 3D surgical guides versus freehand placement of pterygoid implants.

Hypothesis

• H0: No difference in accuracy between techniques.
• Hₐ: there is difference between two techniques Study Design A prospective randomized controlled trial (1:1 allocation) with 12 implants (6 per group(.

Patient Selection Inclusion Criteria: Severe posterior maxillary atrophy (Cawood & Howell V-VI), residual bone height <4mm, age 21-75.

Exclusion Criteria: Contraindications for surgery, uncontrolled systemic diseases, or acute sinus infections.

Methods

• Group A: Implants placed using CBCT-based 3D surgical guides.
• Group B: Freehand placement based on anatomical landmarks.
• Primary Outcome: Implant position accuracy (postoperative CBCT vs. virtual plan(.
• Secondary Outcomes: Surgical time, complications, and stability. Surgical Procedure
• Osteotomy: Angled drilling (45-60°) into the pterygoid process.
• Implant Placement: Torque ≥30 Ncm for primary stability.
• Postoperative Care: Antibiotics, analgesics, and follow-up CBCT at one week. Statistical Analysis Data analyzed using SPSS, with G*Power determining sample size (85% power, α = 0.05(.

Ethical Considerations Approved by institutional review boards, with informed consent and confidentiality maintained.

Study Overview

• Status: Not yet recruiting
• Conditions: Atrophy of the Posterior Maxilla
• Intervention / Treatment: Device: guided surgery technique; Procedure: Free hand technique

• Study Type: Interventional
• Enrollment (Estimated): 12
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: norhan magdy yousef, BDs; Phone Number: +201067534200; Email: nm2650@fayoum.edu.eg
• Study Contact Backup: Name: al shimaa ahmed shaban, professor; Phone Number: +201006047940; Email: aas16@fayoum.edu.eg

Study Locations

• Egypt
  • Fayoum, Egypt, 63514
    • Fayoum University
    • Contact: arfaa sabry hassan, professor; Phone Number: 0020842114095; Email: ash02@fayoum.edu.eg

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Patients with severe posterior maxillary atrophy (Class V-VI Cawood & Howell classification) requiring pterygoid implant placement.
2. Patients with severe alveolar bone atrophy in posterior maxilla (Residual alveolar bone height <4mm in posterior maxilla precluding conventional implant placement).
3. Adequate interarch space ≥7mm for prosthetic rehabilitation.
4. Presence of pneumatized maxillary sinus with insufficient bone for sinus augmentation.
5. Patients aged 21-75 years with completed craniofacial growth.

Exclusion Criteria:

1. Patients with systemic conditions contra-indicating general anesthesia.

2. Patients with conditions contraindicating implant placement (e.g.:

   radiation to the head and neck, intra-venous bisphosphonates, uncontrolled Diabetes mellitus).

3. Patients with acute maxillary sinus infection or maxillary sinus cyst.
4. Restricted mouth opening (less than 3cm inter-arch distance anteriorly).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Guided Surgery group; Implants placed using CBCT-based 3D surgical guides.	Device: guided surgery technique; Clinical examination will be performed and preoperative CBCT will be taken for all the patients prior to the surgery to evaluate the posterior maxilla for the placement of the pterygoid implants.; Ideal pterygoid implant placement will be planned using the BlueSky Bio software (USA) which will be mostly to emerge from the third molar position and to engage the dense pillar of bone formed by the pyramidal process and pterygoid process of sphenoid bone.; surgical guide will be fabricated which will be either soft tissue without flap elevation.
Placebo Comparator: free hand technique group; Freehand placement based on anatomical landmarks.	Procedure: Free hand technique; the surgery will be done without the use of the surgical guides depending on the anatomical landmarks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Accuracy of implant position	The primary outcome will be measured by comparing the position of implant in the virtual plan with that in the postoperative implant or the actual implant and this will be done by making a superimposition of the virtual plan with the postoperative CBCT then putting points on the coronal and apical parts of implants and then start to measure the following data: direct linear measurements between the coronal and apical points of the virtual and actual implants (measured in millimeters); angular deviations between the long axis of virtual and postoperative or actual implants.(measured in degrees); indirect measurements of the coronal and apical points of virtual and actual implants to 3d planes.(measured in mm) All of this will be done for both groups.	the patient will make postoperative CBCT after one week of the surgery to compare it with the preoperative virtual planning done on the preoperative CBCT.

Collaborators and Investigators

• Sponsor: Fayoum University

Study record dates

Study Major Dates

• Study Start (Estimated): July 30, 2025
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 30, 2026

Study Registration Dates

• First Submitted: June 3, 2025
• First Submitted That Met QC Criteria: June 11, 2025
• First Posted (Actual): June 12, 2025

Study Record Updates

• Last Update Posted (Actual): June 12, 2025
• Last Update Submitted That Met QC Criteria: June 11, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: guided surgery; atrophic maxilla; pterygoid implant
• Additional Relevant MeSH Terms: Pathological Conditions, Anatomical; Atrophy
• Other Study ID Numbers: pterygoid implant

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: I still have no decision until i start my research and getting approvals from the patients to protect their right.

Drug and device information, study documents

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