Mucosal microflora in head and neck cancer patients.

OBJECTIVE: To analyse the tongue and buccal microflora prospectively in head and neck cancer patients treated with radiation therapy (RT). METHODS: In 33 dentate patients, microbial samples from the tongue and buccal mucosa were collected pretreatment, during treatment, and 6 months, 1 year and 2 years post-treatment. Microorganisms associated with oral health and oral disorders were analysed using cultivation technique. Oral mucositis was scored at the appointment during treatment. RESULTS: Compared with pretreatment, lactobacilli and Candida increased on the tongue, while streptococci and Neisseria decreased during treatment. Two years post-treatment, Neisseria and Prevotella were decreased and Candida increased. On the buccal mucosa, an increased growth of lactobacilli and increased detection frequencies of the opportunistic bacteria Staphylococcus aureus, Gram-negative enteric rods and enterococci were seen during treatment compared with pretreatment. Seventy per cent showed severe mucositis during treatment. Two years post-treatment the total count as well as streptococci, Neisseria and Fusobacterium nucleatum were decreased and lactobacilli increased compared with pretreatment. CONCLUSION: Despite improvements in treatment for cancer in the head and neck region, microorganisms associated with oral health decrease during treatment and mucosal pathogens increase. Two years post-treatment, levels of acid-tolerant (lactobacilli and Candida) were increased, while acid-sensitive microorganisms (Neisseria and F. nucleatum) were decreased, plausibly due to persisting decreased salivary secretion rate.

Explorative study on mucosal and major salivary secretion rates, caries and plaque microflora in head and neck cancer patients.

OBJECTIVE: To analyse mucosal and major salivary secretion rates, caries and plaque microflora in connection with treatment for cancer in the head and neck region. METHODS: Thirty-three patients were included and the number of teeth, filled surfaces and caries lesions registered. The labial and buccal gland secretion and stimulated whole salivary secretion rates were determined. Supragingival plaque microflora was analysed using cultivation technique. Data were collected pretreatment, during treatment and 6 months, 1 year and 2 years post-treatment. RESULTS: Two years post-treatment, 36% had new caries lesions, which had been restored. The labial secretion was comparable with pretreatment, while the buccal secretion was lower (P < .001). The stimulated secretion rate was lower compared with pretreatment (P < .001) and was ≤0.7 mL/minute for 50%. Growth of lactobacilli increased during treatment (P < .001) and remained increased (P < .001), while growth of mutans streptococci was decreased (P < .01) 2 years post-treatment. Growth of Candida increased over time and was higher 2 years post-treatment compared with pretreatment (P < .001) while growth of Prevotella was lower (P < .01). CONCLUSIONS: Two years post-treatment, the stimulated salivary secretion rate was substantially decreased, acid-tolerant lactobacilli and Candida increased, acid-sensitive microorganisms decreased, and the caries prevalence was low.

Microflora in oral ecosystems in subjects with radiation-induced hyposalivation.

AIM: To analyse the microbial flora in specific oral sites in 13 dentate subjects, 6-8 months after completed radiation therapy (RT group) and in 13 matched controls. MATERIAL AND METHODS: The microflora on the tongue, buccal mucosa, vestibulum, supragingival plaque and subgingival region was analysed using duplicate sampling and cultivation technique. A clinical examination was also performed. RESULTS: Candida albicans was found in one or more sites in 54% of the RT subjects and in 15% of the controls. In three RT subjects, C. albicans was found at all four sites analysed. An unexpected finding was that enterococci were found in all RT subjects and in high number in 38%. None of the controls harboured enterococci. In supragingival plaque, Lactobacillus spp. were detected in 92% of the RT subjects and the number and proportion of Lactobacillus spp. were extremely high compared with the controls. Mutans streptococci were detected in high numbers in 31% of the RT subjects, while they were not detected in 23%. CONCLUSION: The microbial results explain why some RT subjects have an increased susceptibility to oral diseases and stress that site-specific microbial analysis is an important diagnostic tool when planning oral health preventive care for RT subjects.

Oral microbiota associated with hyposalivation of different origins.

We analysed and compared the oral microbial flora in four groups with hyposalivation caused by radiation therapy (RT), primary Sjögren's syndrome (pSS), medication or unknown factors (Unknown), or neuroleptic treatment (Neuro). A control group with normal salivary secretion was also included. The subjects included were 54 +/- 8 years old and had 25 +/- 4 teeth. We analysed their microflora in rinsing samples using a cultivation technique. A marked increase in Lactobacillus spp. and Candida albicans was characteristic of the RT group. In the pSS group, 85% of subjects had high numbers of mutans streptococci despite good oral hygiene, frequent dental visits and fluoride use. The Unknown group had an oral flora similar to that of the controls. In the Neuro group, with a stimulated secretion rate similar to that of the Unknown group, the numbers of aciduric and acidogenic microorganisms were close to those in the pSS group. The results indicate that changes in the oral microflora associated with hyposalivation are related to the reason for the hyposalivation rather than to the magnitude of the decrease in the salivary secretion rate.

Dentinal innervation of impacted human third molars.

Five totally impacted third molars were studied in the transmission electron microscope for the presence of nervous structures in the dentin before eruption. In contradiction to earlier studies available, nervous structures were found in the predentin and the dentin of the impacted third molars in different parts of the crown and also in the predentin of the root.