Aerobic bacteria in the oral cavity of patients with removable dentures

Abstract

Purpose: Determination of bacterial composition in the oral cavity of patients with removable dentures and with own dentition (without dentures).

Material and methods: Bacteriological investigations were performed in 55 patients from the department of internal medicine (32 diabetic patients) and 40 patients treated in surgical department (25 patients with malignancy). Palate mucosa and tongue dorsa swabs were collected from two groups of patients, and additionally swabs from mucosal part of denture surfaces in prosthetic patients. Cultures in oxygenic and microaerophilic (5% CO2) conditions were conducted on solid non-selective and selective media as well as media enriched with 5% sheep blood. Standard procedures of bacterial culture and identification were applied.

Results: Among 95 of examined patients, 57 (60.0%) with removable dentures and 38 (40.0%) had their own dentition. As far as prosthetic patients were concerned, the rate of bacterial isolations from palate, tongue dorsa and denture plaque swabs were generally comparable (p > 0.05); in number and species compositions. Statistically significant differences were observed in the bacterial composition of denture plaques, palate and tongue dorsa in patients with and without abdominal cancers. Patients without cancer did not reveal staphylococci and enteric bacteria in the samples from a various sites of their oral cavities. These bacteria were most common in cancer patients. Similar (in number and species) composition of bacteria occurred in palate and tongue swabs in patients without dentures (p > 0.05). The incidence rate of aerobic bacteria in denture plaques and palatal mucosa of patients with (37/57; 64.9%) and without (20/57; 35.1%) denture associated stomatitis were comparable (except for Neisseria spp.).

Conclusions: 1) Generally, there were no statistically significant differences in species composition of bacteria isolated from the hard palate and tongue dorsa in patients with and without removable dentures. 2) Staphylococcus spp. and Gram-negative enteric bacilli were isolated more often from denture plaque, palate and tongue dorsa of cancer patients than from patients without cancer (p < 0.05). 3) Staphylococcus spp. was isolated more frequently from denture plaques of diabetic patients compared with non-diabetic patients (p < 0.05). 4) No significant differences observed in isolation frequencies (%) of aerobic bacteria in denture plaques and palatal mucosa of patients with and without denture associated stomatitis.