Journal Article

Comparison of retentive force and deformation of selective laser melting and conventional cobalt-chromium clasps of removable partial denture

Mohamed, Sara Zaky, Husseiny, Eman, Rokaya, Dinesh, Youssef, Reham Abdel Fattah, Eltamaly, Nada

2025

Overview

Objective The objective of the study was to compare the retentive force and deformation of conventional casting and selective laser melting (SLM) cobalt-chromium (Co-Cr) clasps assembly of removable partial dentures (RPD) following recurrent insertion and removal forces. Materials and methods A total of 12 RPD samples were used in this study, which were divided equally into two groups: Group A (indirect digital conventional casting) and Group B (direct digital SLM) Co-Cr clasp assembly. The retention was measured using a universal testing machine after the recurrent removal and insertion of the RPD. Deformation was measured using Geomagic Control X professional metrology software. The retention and deformation data were compared between the two groups using an independent sample t-test. The association between the variables was studied using the Pearson correlation test. A statistical significance was established at P  < 0.05. Results A statistically significant difference in retention was observed between the two groups. Direct digital SLM Co-Cr clasp assembly showed higher retention and lower distortion compared to the indirect digital conventional casting Co-Cr clasp assembly. A significant negative correlation (correlation coefficient=-0.807, p-value = 0.004) between deformation and retention suggests that increased deformation reduces the retention. Conclusion The direct digital SLM Co-Cr clasp assembly in the RPD showed higher retentive force and lower deformation than the indirect digital conventional casting Co-Cr clasp assembly in the RPD.

• Publisher: BioMed Central,Springer Nature B.V,BMC
• Subject: 3-D printers / Alloys / CAD / Chromium / Chromium alloys / Chromium Alloys - chemistry / Co-Cr claps / Cobalt / Computer aided design / Deformation / Dental Casting Technique / Dental clasp / Dental Clasps / Dental Stress Analysis - instrumentation / Dentistry / Denture / Denture Design / Denture Retention - instrumentation / Denture, Partial, Removable / Dentures / Humans / Laser sintering / Lasers / Manufacturers / Manufacturing / Materials Testing / Medicine / Melting / Metal fatigue / Oral and Maxillofacial Surgery / Partial denture / Retention / Retentive force / RPD clasps / Scanners / Statistical analysis / Stress, Mechanical / Surface Properties / Teeth