Oral Hygiene Care and Microflora in Elderly Residents
Oral Hygiene Care and Microflora in Elderly Residents
Objective: The effect of weekly professional oral care on the composition of the oral flora
 in dentate, dependent elderly residents was followed during a 12-month period.

 Background: Long-term, regular professional oral hygiene care reduces the total number of
 microorganisms and oral disease-related microorganisms. Less is known about the effect on the
 quality/composition of the remaining oral flora.

 Materials and methods: Thirty-three subjects were included in the study group and 35 in the
 control group. Dental status, presence of supragingival-plaque, labial minor gland secretion
 rate, and prescription medicines were recorded. Microbial samples, collected from
 supragingival plaque and the dorsum of the tongue, were analyzed using cultivation technique.
Ethics statement The study was approved by the Ethics Committee at the University of
 Gothenburg, Sweden (Permit Number 039/00).

 Study and control groups After giving an informed and written consent to participate, either
 by the subjects themselves or by a relative or a guardian, 68 subjects were recruited from
 two nursing homes for elderly persons. The nursing homes, belonging to the same institution
 and having the same leadership, are situated in the same area of the city. The study group
 was recruited from one of the nursing homes and consisted of 21 women and 12 men. The control
 group, recruited from the second nursing home, consisted of 23 women and 12 men. To be
 included in the study, the subjects had to have at least 10 natural teeth and no removable
 dentures and be able to follow simple instructions, such as open and close the mouth. The
 subjects were included in the study in the order they gave their informed consent and
 fulfilled the inclusion criteria. Throughout the study period, the subjects in both groups
 were eligible for dental care for dependent individuals, as regulated by law in Sweden,
 including an oral health care assessment free of charge, basic dental care at subsidized
 rates, and nursing home personnel trained in oral health care.

 Intervention The study group received professional oral care, once a week throughout the
 12-month study period, by either of two dental hygienists. The oral care was carried out in
 the residents´ private rooms with the participant sitting in his/her own chair or lying in
 bed. The treatment included brushing of the teeth, at labial and lingual sides, with use of
 an electric toothbrush (Oral-B Professional Care 7000) and a 1100 ppm sodium fluoride
 dentifrice (Zendium Classic, Opus Health Care AB/Zendium). Inter-dental cleaning was carried
 out using inter-dental brushes (TePe: TePe, Malmö, Sweden) and toothpicks (TePe Birch: TePe,
 Malmö, Sweden). Information and training in oral hygiene procedures were given to those in
 the study group capable to understand instructions.

 At the start of the intervention, each subject in the study group, as well as their main
 responsible nursing aid, received an electric toothbrush of the same kind as was used by the
 two dental hygienists (Oral-B Professional Care 7000), and instructions and training on how
 to use the brush. In the control group, the oral health care procedures followed the ordinary
 routines for the department.

 Collection of clinical data and samples for microbial analysis Clinical examinations,
 measurements of labial minor gland salivary secretion rate, and microbial samplings were
 performed between 9 and 12 am (by author KL K) and were carried out in the residents´ private
 rooms. All microbial sampling was performed in duplicate, one week apart. The clinical
 examination was performed at the first of the two duplicate sampling occasions. Plaque
 registration followed by the collection of supragingival plaque for microbial analysis was
 performed at four sites, in that order. The sites selected were interproximally the upper
 right first and second molars, the lower left first and second molars, the upper right second
 incisor and the canine, and the lower left second incisor and the canine. If one or more of
 these teeth were missing, the closest available site was selected. The measurement of the
 labial minor gland salivary secretion rate, followed by microbial sampling from the tongue,
 was performed in that order and at the end of the registration and sampling sessions.

 In both the study and control groups, clinical data, data on prescription medicines, the
 labial minor gland salivary secretion rate, and microbial samples were collected at the
 baseline and at the end of the 12-month study period. In the study group, additional plaque
 registration and sampling for microbial analysis were performed after 3, 6, and 9 months from
 the baseline.

 Clinical examination The clinical examination was carried out, in the light of an adjustable
 headlight, using a dental mirror and a dental probe. The number of natural teeth, clinically
 visible caries lesions and plaque were recorded. Plaque was recorded as no visible plaque
 (score 0), visible but thin plaque (score 1) or visible thick plaque (score 2). A mean of the
 plaque scores recorded at the four interproximal sites selected for registration was
 calculated.

 Prescription medicines Data on prescription medicines was collected from the residents´
 medical records.

 Labial minor gland salivary secretion rate For measurement of the labial minor gland salivary
 secretion rate, performed as described by Eliasson et al., the area of the lower labial
 mucosa was gently dried with a cotton pad. A pre-cut piece of a standard filter paper was
 then placed for 15 s near the midline approximately 3 mm from the outer border of the mucosa.
 The volume of liquid absorbed by the filter paper was measured using a calibrated Periotron®
 (8000, ProFlow™ Inc., Amityville, NY, USA). At each examination, four samples were collected
 from each subject and an individual mean was calculated.

 Microbial sampling and analysis Microbial samples were collected from the supragingival
 plaque and the dorsum of the tongue. An experienced laboratory assistant blinded to which
 group of subjects, study or control group, and to which of the examination occasions the
 samples were collected from, analyzed the samples.

 The supragingival plaque samples were collected using sterile toothpicks (TePe Birch) and
 pooled. The tongue samples were collected using sterile tweezers, cotton pellets and plastic
 spatulas. The spatula, with a circular hole 1.5 cm diameter, was placed on the back part of
 the dorsum. A cotton pellet, immersed in sampling fluid, was swept over the area inside the
 hole. The two samples were each transferred to 3.5 ml of transport medium VMGA III and
 processed within four hours.

 The analyses of the samples were performed as previously described using enriched blood agar
 plates and selective agar plates. The total number of microorganisms growing under anaerobic
 conditions, the total number and proportion of streptococci and the number and proportion of
 Streptococcus sanguinis/oralis and Streptococcus salivarius, both associated with good oral
 health, mutans streptococci, lactobacilli and Actinomyces spp, associated with dental caries,
 F. nucleatum, and P. intermedia/nigrescens, associated with gingival inflammation, P.
 gingivalis and A. actinomycetemcomitans, associated with periodontitis, Candida albicans,
 Staphylococcus aureus, and enteric rods, associated with mucosal and aspiratory infections,
 were calculated. The detection limit was 100 colony-forming units for all species except A.
 actinomycetemcomitans, where the detection limit was 10 colony-forming units. If possible,
 the number of microorganisms was calculated from their number on a plate giving 30 - 300
 colonies. A mean of the results from the duplicate samplings was calculated.

 Statistical methods To normalize the microbial data, the numbers were transformed
 logarithmically. Zero counts were treated as one colony forming unit/ml. Mean and median
 values and standard deviations were calculated. One-way ANOVA was used for the analysis of
 differences between the study and control groups. Two-way ANOVA was used for statistical
 analysis of differences at different time points within the two groups. Results were regarded
 statistically significant at p-values < 0.05. Owing to the multiple influence aspect,
 isolated significances should be interpreted with some caution.
Inclusion criteria

 -  10 or more natural teeth

 -  no removable dentures

 -  no or mild cognitive impairments

 Exclusion criteria

 -  less than 10 natural teeth

 -  removable dentures

 -  severe cognitive impairments