Effects of improvements of poorly fitting dentures and new dentures on masticatory performance.

The effect of four modifications to improve the fit and maxillomandibular relationships of poorly fitting dentures and the insertion of new dentures on masticatory performance was assessed in 21 denture wearers. A 2-week adaptation period was allowed for each of the four modifications and 3 weeks and 12 weeks of adaptation for new dentures. The preferred side masticatory performances were not appreciably affected by either the modifications to improve the fit of the original dentures or the new dentures. In most instances there was a slight decline in performance. Three denture modifications caused significant declines in the carrot-swallowing threshold performances and the new dentures in the peanut-swallowing threshold performance. In other words, the denture wearers had a greater percentage of coarse particles in their bolus ready for ingestion when they chewed with altered or new dentures compared with original dentures. However, they chewed faster and applied fewer chewing strokes with their modified and new dentures. A steady but gradual improvement in the mean performance score with carrots was noted with time after the insertion of new dentures. Dentists and patients need to understand that adaptation to new or modified old dentures may be a long, drawn-out process for some patients.