Prosthetic Aspects of All-On-Four Implants

Introduction

• Webinar by Micro Devil
• Focus: Prosthetic aspects of all-on-four cases
• Covers digital and traditional workflows

All-On-Four Implant Case Overview

• Typically involves four implants in the maxilla or mandible
• Minimal to no grafting
• Two anterior implants placed vertically, two posterior implants tilted for support
• Multi-unit abutments connected to implants
• Titanium cylinders used for temporary appliance connection

Clinical Procedure and Temporary Appliance Conversion

1. Initial Setup: Denture Construction
   • Immediate dentures constructed
   • Teeth extraction and denture fitting
   • Ball clasps used for stability and occlusion
2. Surgery and Implant Placement
   • Teeth and alveolus removal
   • Multi-unit abutments placed on implants
   • Titanium cylinders connected for temporary appliance
3. Temporary Appliance Conversion
   • Denture holes drilled to expose titanium cylinders
   • Acrylic material used for cylinder pickup
   • Dentures converted to bolt-down appliances

Laboratory Procedure

1. Impression and Cast Creation
   • Use of master casts and fast-setting stones
   • Pouring casts in stone
2. Mounting and Alignment
   • Use of occlusal index for mounting
   • Adjustment of master casts for fitting
3. Denture Realignment and Conversion
   • Trimming and contouring temporary appliances
   • Polishing and finishing
   • Mouth guard construction for patient use

Final Appliance Construction

1. Traditional Workflow
   • 5 appointments from impression to delivery
   • Includes face bow, jaw relation records, and setup trials
2. Expedited Digital Workflow
   • Combines impression and records into one appointment
   • Involves fully milled acrylic appliances
   • Use of virtual setups and hybrid try-ins

Additional Complex Cases

• Cases with limited interarch space (Montreal bar technique)
• Workflow adjustment for less than ideal conditions

Maintenance and Follow-Up

1. Professional Cleaning
   • Use hydro floss for irrigation
   • Regular check-ups advised
2. Handling Implant Failures
   • Torque testing at surgery and follow-up
   • Radiographic evaluation

Q&A Highlights

• Torque requirement: 35 Newton centimeters for implants, 15 for multi-unit abutments
• Cantilever design: AP spread method
• Dealing with pre-existing implants: Radiographic and torque testing
• Workflow scheduling: Combine steps to reduce appointments
• Frequency of professional cleaning: Annually or based on patient needs
• Handling acrylic breakage: Use milled acrylic for durability
• Warranty considerations: Typically 1-5 years depending on manufacturer and lab

Conclusion

• Success of all-on-four implants in esthetics and functionality
• Importance of digital and traditional workflows in prosthetic dentistry
• Upcoming webinar on new normal prosthetics for implant overdentures