Determination of the lingual border of lower complete dentures: How to use a silicone impression material?

OBJECTIVES: This study aimed to clarify the efficacy of a border-moulding procedure with low-flow silicone impression material compared with a conventional compound to complete denture fabrication. It also aimed to evaluate the influence of various functional tasks during the lingual-side moulding procedure regarding the depth and width of the border. METHODS: Ten dentate subjects (three men, seven women; average age 30 years) were enrolled in this study after giving informed consent. A specially designed custom impression tray for the mandibular lingual side was fabricated for each subject. With the tray and heavy-body-type silicone material, lingual border moulding was performed that included four functional tasks: tongue protrusion (TP), licking the upper lip with the tongue (UL), swallowing (SW), and placing the tongue tip to the palate (PP). RESULTS: Within the limitations of this study, the results suggested that heavy-body silicone impression material is satisfactory for use in the border-moulding procedure, giving reproducible results. CONCLUSION: There were no significant differences among the functional tasks regarding the depth and width of the lingual flange except for swallowing, which exhibited the largest values.