A randomised controlled study comparing the anterior mandibular labio-lingual neutral zone position in edentulous subjects with and without their maxillary denture in-situ

Opinion is divided as to whether the neutral zone impression to determine the labiolingual position of mandibular complete dentures requires the maxillary denture to remain in-situ or not. Two such neutral zone impressions were recorded for each of the 12 participants of this randomised controlled study. The presence of the maxillary denture made no statistically significant mean difference in labio-lingual position of the mandibular neutral zone. Within the confines of this research protocol there was no evidence that the shift in the labio-linguial position of the anterior mandibular neutral zone was consistently affected by the presence of a maxillary appliance.