Laser-Sintered versus Conventional Cobalt-Chromium Bars in Implant-Supported Complete Mandibular Overdentures: An In Vitro Strain Analysis Comparative Study

Abstract

Objective

The aim of this study was to compare the effect of laser-sintered and conventional cobalt-chromium bars on strain distribution around implants in mandibular implant-supported overdentures.

Materials and Methods

A three-dimensional (3D) epoxy resin model for completely edentulous mandible was used for this study. Two implants were placed in the canine region, and the 3D model was scanned by a laboratory scanner. Twelve cobalt-chromium bars were divided into two groups. Group 1 includes six bars that were designed by software and created using the laser sintering method. Group 2 includes six bars that were made using computer-aided design and computer-aided manufacturing to make a wax model, fabricated by a conventional lost wax-casting technique. Each implant was surrounded by four channels in the epoxy resin model, and four strain gauges were cemented. A universal testing machine was used to apply the load, and a strain measuring analysis was performed.

Results

Null hypothesis was rejected as there was significant difference in strain distribution around implants between both groups for the microstrains around the implants in bar-retained implant-supported prostheses, in both bilateral and unilateral results.

Conclusion

The laser sintering method showed better results in comparison with conventional methods in fabrication of bar-retained implant-supported prostheses due to less trauma to the implant and supporting structures.

Keywords

cobalt-chromium bars - implant supported overdenture - direct 3D printing - strain gauge analysis

Publication History

Article published online:
27 January 2025

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