Comparison of bacterial flora in the oral cavity of children and adults

The aim of the study was to assess levels of occurrence and number of aerobic bacteria hemolysing and non-hemolysing, anaerobic bacteria, streptococci hemolysing and non-hemolysing, staphylococci, and bacteria responsible for tooth decay (Streptococcus mutans and Lactobacillus spp.) on oral cavity in children and adults. The results obtained indicate the difference of the level of occurrence of, aerobic bacteria hemolysing and non-hemolysing, anaerobic bacteria, streptococci hemolysing and non-hemolysing, staphylococci, and bacteria responsible for tooth decay (Streptococcus mutans and Lactobacillus spp.) was not statistically significant in either group. The counts and average values of the counts for aerobic bacteria non-hemolysing, anaerobic bacteria, streptococci hemolysing and non-hemolysing and Streptococcus mutans turned out to be statistically significantly larger in adults than in children. However for aerobic bacteria hemolysing, staphylococci and Lactobacillus spp. the difference of the counts was not statistically significant in either group.     

Inhibitory effect of sodium fluoride and chlorhexidine on the growth of oral lactobacilli

The accumulation of microorganisms in dental plaque is related to the etiology of caries and periodontal disease, with a high prevalence worldwide. The prophylactic measures include the use of chemical agents as NaF and chlorhexidine. Lactic acid bacteria are members of the normal microbiota of the oral cavity being discussed with regard to their beneficial or detrimental effect in this environment. The present study was performed to determine the growth of some species of Lactobacillus at different concentrations of NaF and chlorhexidine. The strains were isolated from both caries-free and caries patients. Their growth parameters were evaluated by the application of the Gompertz model to the experimental data of optical density as a measurement of growth. The degree of inhibition of the growth of all of the lactobacilli studied was different, depending on each particular strain. NaF at 1 mmol x L(-1) inhibited between 5% and 46%, at 5 mmol x L(-1) between 13% and 65%, and at 20 mmol x L(-1) between 57% and 84%. CHX at higher concentrations (197 and 98 mmol x L(-1) showed a complete inhibition of some of the strains. The significance of the results was evaluated by the application of a multivariate analysis and also compared with the inhibition of pathogenic Streptococcus mutans and with lactobacilli strains from collection cultures.     

Oral administration of Lactobacillus plantarum strain Lq80 to weaning piglets stimulates the growth of indigenous lactobacilli to modify the lactobacillal population

The composition and the number of fecal or intestinal lactobacilli were determined in weaned piglets before (pre-administration and day 0) and during (days 4, 7, and 14) the administration of Lactobacillus plantarum strain Lq80 (daily dose=10(10) cells). Fecal or intestinal lactobacilli were isolated, and the isolates were grouped by RAPD-PCR and further identified by 16S rDNA partial sequences. During administration, the number of lactobacilli in feces and intestinal contents (log cfu/g) increased from day 0 to day 4 (7.96 vs. 10.07, p<0.05), to day 7 (7.96 vs. 10.18, p<0.05), and to day 14 (7.96 vs. 9.02, p=0.07) in the administered group, although L. plantarum was isolated from the feces of piglets in the administered group at 5.0x10(6 cfu/g. The level of culturable lactobacilli was significantly higher on day 7 in the administered group than in the control group (8.93 vs. 10.18, p)=0.0002). Furthermore, the minor species in the lactobacillal population under the control condition become detectable with the administration of strain Lq80. The oral administration of L. plantarum strain Lq80 was effective to stimulate the development of the lactobacillal population in the intestine of post-weaning piglets.     

Impact of two probiotic Lactobacillus strains feeding on fecal lactobacilli and weight gains in chicken

Two probiotic strains, Lactobacillus agilis JCM 1048 and L. salivarius subsp. salicinius JCM 1230 isolated from chicken intestine, exhibited probiotic characteristics that can be applied for chicken production. After 7 days of probiotic feeding (FD7), the count of intestinal lactobacilli in the probiotic group (group P, n=10) was significantly (p<0.05) higher than that in the control group (group C, n=9). After 40 days of probiotic feeding (FD40), the lactobacilli and enterococci counts were stable but the Enterobacteriaceae number was significantly reduced (p<0.05). A total of 163 isolated lactobacilli were identified as the L. acidophilus/gallinarum group (49.7%), L. agilis (30.7%), L. salivarius (9.2%), L. reuteri (9.2%), and Lactobacillus spp. (1.2%). The probiotic lactobacilli positively affected the Lactobacillus biota in chickens at FD7, with a significant increase in the number (p<0.05) of L. agilis and group P. The viable counts of each Lactobacillus species at FD40, however, showed no differences between two groups. An increasing incidence of L. agilis was also noted with probiotic feeding. The probiotic effect of two strains resulted in significantly increased weight gains (10.7%) of group P in comparison with group C at FD40 (p<0.01).     

Inhibition of Streptococcus mutans NS adhesion to glass with and without a salivary conditioning film by biosurfactant- releasing Streptococcus mitis strains

The release of biosurfactants by adhering microorganisms as a defense mechanism against other colonizing strains on the same substratum surface has been described previously for probiotic bacteria in the urogenital tract, the intestines, and the oropharynx but not for microorganisms in the oral cavity. Two Streptococcus mitis strains (BA and BMS) released maximal amounts of biosurfactants when they were grown in the presence of sucrose and were harvested in the early stationary phase. The S. mitis biosurfactants reduced the surface tensions of aqueous solutions to about 30 to 40 mJ m(-2). Biochemical and physicochemical analyses revealed that the biosurfactants released were glycolipids. An acid-precipitated fraction was extremely surfactive and was identified as a rhamnolipidlike compound. In a parallel-plate flow chamber, the number of Streptococcus mutans NS cells adhering to glass with and without a salivary conditioning film in the presence of biosurfactant-releasing S. mitis BA and BMS (surface coverage, 1 to 4%) was significantly reduced compared with the number of S. mutans NS cells adhering to glass in the absence of S. mitis. S. mutans NS adhesion in the presence of non-biosurfactant-releasing S. mitis BA and BMS was not reduced at all. In addition, preadsorption of isolated S. mitis biosurfactants to glass drastically reduced the adhesion of S. mutans NS cells and the strength of their bonds to glass, as shown by the increased percentage of S. mutans NS cells detached by the passage of air bubbles through the flow chamber. Preadsorption of the acid-precipitated fraction inhibited S. mutans adhesion up to 80% in a dose-responsive manner. These observations indicate that S. mitis plays a protective role in the oral cavity and protects against colonization of saliva-coated surfaces by cariogenic S. mutans.     

In-vitro bacteriocin-mediated antagonism by oral streptococci against human carrier strains of staphylococci

All strains of oral streptococci tested and specially those of Streptococcus mutans, Strep. sanguis and Strep. mitior produced more than one distinct bacteriocin-like substance with variable inhibitory activity on 20 indicator staphylococci. Inhibitory activity was comparatively higher on nasal strains of Staph. aureus and Staph. epidermidis than on strains of both species isolated from the mouth. Nineteen of 20 staphylococcal indicators were inhibited by 1-12 of the 12 effector streptococci. Sensitivity of nasal staphylococci to bacteriocins (frequency of positive inhibitory tests and total inhibition zone diameters) was significantly higher (P less than 0.001, chi 2 test and P less than 0.05, t test respectively) than that of oral ones. The sensitivity of nasal over oral Staph. aureus (P less than 0.001 and P less than 0.01) and of oral Staph. epidermidis over oral Staph. aureus (P less than 0.01 and P less than 0.05) was also significantly higher. The evaluation of variability of inhibitory patterns of bacteriocins produced by streptococci (p-typing), of sensitivity patterns of staphylococci to bacteriocins (s-typing) and of the significantly higher sensitivity of nasal over oral staphylococci to bacteriocins from the epidemiological and ecological viewpoints are discussed.     

Antibacterial protection and the microbiological status of the oral cavity in Sj?gren's disease

The microflora of the oral cavity was studied with a view to the evaluation of the microbiological status and the content of lysozyme in mixed saliva samples from 14 patients with Sj?gren's syndrome and the control group of 19 persons. Disturbances in the biocenosis of the oral cavity of the patients, characterized by the increased occurrence of rod-shaped forms of lactobacilli, yeast-like fungi of the genus Candida and cariogenic streptococci (S. mutans) in the cultures obtained by the inoculation of oral smears, was detected. This "cariogenic situation" was confirmed by clinical data on the stomatological status. In patients with Sj?gren's syndrome the intensity of caries, determined by the ratio of carious, filled and extracted teeth, was high and reached 27.4 +/- 1.0 in comparison with 15.3 +/- 0.7 in the control group (P less than 0.05). A decrease in the level of mixed saliva secretion and in the content of lysozyme in secreted saliva was noted in the patients in comparison with the control group (P less than 0.05). The results thus obtained indicate that in Sj?gren's syndrome the use of the preparations of eubiotic microorganisms with a view to the correction of the microflora of the oral cavity, as well as the application of 0.1% lysozyme solution to the mucous membrane of the oral cavity, may be recommended among other therapeutic measures.     

Antimicrobial susceptibility of intestinal bacteria from Swiss poultry flocks before the ban of antimicrobial growth promoters

From the crop and the caecum of Swiss broilers slaughtered between November 1997 and January 1998, Escherichia coli, enterococci, staphylococci, lactobacilli and Campylobacter species were isolated. After identification to the genus or species level, their minimal inhibitory concentrations (MIC's) for several clinically used antimicrobial agents were determined with the E-Test stripes and compared to those from studies in other European countries. All strains of Enterococcus faecalis (n = 38), E. faecium (27), staphylococci (n = 39) and lactobacilli (n = 14) showed a hundred percent resistance against bacitracin which was included in the feed of the mother animals, but not in the feed of the investigated animals. E.coli strains (n = 60) showed higher resistance incidences than in comparable studies from Finland and Denmark, but lower than those in studies from Italy and Germany. In staphylococci, low resistance rates were observed. A high susceptibility of the 13 Campylobacter jejuni strains was found against therapeutically used antimicrobials. These data can be used as a baseline to determine antibiotic resistance rates after implementation of the growth promotor ban in 1999 in Switzerland.     

In-vitro bacteriocin-mediated antagonism by oral streptococci against human carrier strains of staphylococci

All strains of oral streptococci tested and specially those of Streptococcus mutans, Strep. sanguis and Strep. minor produced more than one distinct bacteriocin-like substance with variable inhibitory activity on 20 indicator staphylococci. Inhibitory activity was comparatively higher on nasal strains of Staph. aureus and Staph. epidermidis than on strains of both species isolated from the mouth. Nineteen of 20 staphylococcal indicators were inhibited by 1–12 of the 12 effector streptococci. Sensitivity of nasal staphylococci to bacteriocins (frequency of positive inhibitory tests and total inhibition zone diameters) was significantly higher ( P < 0·001, χ² test and P < 0·05, t test respectively) than that of oral ones. The sensitivity of nasal over oral Staph. aureus ( P < 0·001 and P < 0·01) and of oral Staph. epidermidis over oral Staph. aureus ( P < 0·01 and P < 0·05) was also significantly higher. The evaluation of variability of inhibitory patterns of bacteriocins produced by streptococci (p-typing), of sensitivity patterns of staphylococci to bacteriocins (s-typing) and of the significantly higher sensitivity of nasal over oral staphylococci to bacteriocins from the epidemiological and ecological veiwpoints are discussed.     

In vitro growth and acid production by mutans streptococci on traditional African foods

The growth rate and production of acids by mutans streptococci (MS) are influenced by their ability to ferment different dietary carbohydrates. This suggests that the nutrient environment in the oral cavity affects bacterial virulence. The aim of this study was to investigate the effect of maize, samp and brown bread on the growth and acidogenicity of this species. Six laboratory references and five clinical strains isolated from the dental plaque of South African black and 'colored' (historical race classification) children were studied in batch culture on maize, samp (coarsely ground maize), brown bread and compared against a 3% sucrose control. The doubling time of bacterial strains was prolonged in maize (1.9-17.5 h) and samp (2.4-18.4 h), and the number of cell divisions was low. Staple foods accounted for 25% (F=5.98; P=0.0007) and MS strains 30.78% (F=2.84; P=0.009) of the total variance. The fermentation of samp and maize showed the least drop in pH of the culture medium, ranging between 0.54 and 1.06 and 0.69 and 2.28 pH units respectively, with variation between strains most significant in maize (F=33.62; P<0.0001). The total mean concentration of acids produced was highest in bread (25.13 mM/mL) and samp (17.00 mM/mL) which was comparable to Brain Heart Infusion broth (16.49 mM/mL) and a basal synthetic medium (17.96 mM/mL) containing 3% sucrose, but the yield of lactate, acetate and formate was low during the fermentation of samp (0.50 mM/mL), BHI+3% sucrose (4.12 mM/mL) and brown bread (0.06 mM/mL) respectively. Results indicated that maize and samp do not optimally support the growth or acid production by MS, and the varying response of test strains demonstrates the strain variability of this species to different carbohydrate sources in the diet.     

Complete genome sequence of the serotype k Streptococcus mutans strain LJ23

Streptococcus mutans is the major pathogen of dental caries and occasionally causes infective endocarditis. Here we report the complete genome sequence of serotype k S. mutans strain LJ23, which was recently isolated from the oral cavity of a Japanese patient.     

Oral glucose clearance in nonagenarians in relation to functional capacity,medication and oral variables

Objectives: To study oral sugar (glucose) clearance and to examine some factors which were believed to either influence or be dependent upon oral glucose clearance. Design: Cross-sectional, clinical study with analysis of records. Setting: Göteborg gerontological and geriatric population studies, Göteborg University, Sweden. Subjects: 71 community-dwelling individuals, 27 men and 44 women, of a representative sample of 260 92-year-old persons. Intervention and Main outcome measures : Glucose concentration was measured in saliva after chewing of a glucose tablet and the clearance was assessed by three different variables: (i) the initial salivary glucose concentration, (ii) the area under the curve (AUC) and (iii) the clearance time. Results: The glucose clearance showed a wide inter-individual variation, which could be explained partly by differences in oral state, chewing time, stimulated salivary secretion rate and medication use. A positive correlation was found between the clearance variables and the number of lactobacilli and mutans streptococci in saliva and the percentage of untreated root caries lesions of the total number of exposed root surfaces. Conclusions : A slow oral sugar clearance is more common among 92-year-olds than younger adults earlier reported in other studies, particularly in those who have uncompensated functional impairments and a high medication history. A decreased oral glucose clearance was associated with high counts of salivary lactobacilli and mutans streptococci and a high proportion of untreated root caries lesions.     

Substantivity of zinc salts used as rinsing solutions and their effect on the inhibition of Streptococcus mutans

The antimicrobial efficacy of zinc (Zn) salts (sulfate and acetate) against Streptococcus mutans (S. mutans) present in the oral cavity was tested in this study. The substantivity of Zn salts was assessed by determining the concentration of Zn in whole, unstimulated saliva and by measuring the magnitude of suppression of salivary S. mutans, 2h after rinsing. The concentration of Zn was measured by atomic absorption spectrometry (AAS) with electrothermal atomization (ET AAS) in saliva sampled before (basal) and 24h after mouth rinsing with different concentrations of Zn (0.1%, 0.5% and 1%) administrated as sulfate and acetate. The estimation of Zn levels in samples collected 30, 60, 90 and 120 min after rinsing was carried out by AAS with flame atomization (FAAS). Immediately after rinsing, the concentration of Zn in saliva sharply increased with respect to the baseline values (0.055+/-0.017 mg/L), followed by a sustained decrease, probably due to clearance of salivary flow or swallowing during sampling. A significant reduction (>87%) in the total mean S. mutans counts was found 2h after rinsing either with sulfate or acetate solutions, as evidence of the high substantivity and effectiveness of the Zn salts tested. A statistically significant inverse relationship (p<0.001 and the Pearson correlation coefficients between -34% and -50%) was found between Zn levels and the respective pH values measured in the samples collected 60 and 120 min after rinsing, sustaining the theory of bacterial glycolysis inhibition.     

Adaptation and Probiotic Potential of Lactobacilli,Isolated from the Oral Cavity and Intestines of Healthy People

The present study shows that, from 300 Lactobacillus strains isolated from the oral cavity and large intestine of 600 healthy people, only 9 had high antagonistic activity against pathogens and opportunistic pathogens. All antagonistic strains of lactobacilli have been identified by 16S rRNA sequencing and assigned to four species: Lactobacillus fermentum, Lactobacillus rhamnosus, Lactobacillus plantarum, and Lactobacillus casei. In addition, these lactobacilli appeared to be nonpathogenic and had some probiotic potential: the strains produced lactic acid and bacteriocins, showed high sensitivity to broad-spectrum antibiotics, and were capable of forming biofilms in vitro. With the help of PCR and specific primers, the presence of genes for prebacteriocins in L. plantarum (plnEF, plnJ, plnN) and L. rhamnosus (LGG_02380 and LGG_02400) has been revealed. It was found that intestinal strains of lactobacilli were resistant to hydrochloric acid and bile. Lactobacilli isolated from the oral cavity were characterized by a high degree of adhesion, whereas intestinal strains were characterized by average adhesion. Both types of lactobacilli had medium to high rates of auto-aggregation and hydrophobicity and could coaggregate with pathogens and opportunistic pathogens. Additionally, the ability of the lactobacilli strains to produce gasotransmitters, CH₄, CO₂, C₂H₆, CO, and NH₃, has been revealed.     

Prevalence of periodontopathic bacteria on the tongue dorsum of elderly people

Objectives: The aim of this study was to analyse the prevalence of oral bacteria on the dorsum of the tongue. In addition, the relationship between the number of teeth and the microflora present on the coating of the tongue in a population of 85‐year‐old people was assessed. Subjects and methods: Two hundred and five individuals (89 males, 116 females) from the same geographical area who were 85 years of age were examined. Five periodontopathic bacteria (Porphyromonas gingivalis, Tannerella forsythia, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, and Treponema denticola) and one cariogenic bacterium (Streptococcus mutans) were analysed using a polymerase chain reaction assay of tongue samples from the population. Results: Periodontal bacteria‐positive individuals have more teeth than that of periodontal bacteria‐negative people. Between the periodontal bacteria‐positive and ‐negative individuals, there were significant differences in the mean number of teeth for P. gingivalis (p < 0.0001), T. denticola (p < 0.001), F. nucleatum (p = 0.002), and T. forsythia (p = 0.005), while there were no significant differences for A. actinomycetemcomitans (p = 0.998) or S. mutans (p = 0.147). Conclusions: A wide range of species, including anaerobes, was detected in 85‐year‐old subjects. It was found that the detection of periodontal bacteria on the tongue coating increased with the number of teeth. There was a positive relationship between the tooth number and periodontopathic bacteria, except for A. actinomycetemcomitans.These results suggest that tongue care is essential for preventing oral disease and needs to be part of any oral care programme in elderly people.     

Effect of a mouthrinse containing Malva sylvestris on the viability and activity of microcosm biofilm and on enamel demineralization compared to known antimicrobials mouthrinses

The purpose of this study was to evaluate the antimicrobial (anti-biofilm) and anti-caries (enamel demineralization prevention) effects of Malva sylvestris (Malvatricin^® Plus) compared with known antimicrobial mouthrinses. Microcosm biofilm was produced on enamel, using inoculum from pooled human saliva mixed with McBain saliva (0.2% sucrose) for 14 days. The biofilm was treated with mouthrinses for 1 min day^?1. Oral-B^® Complete, Listerine^® Zero and Malvatricin^® Plus had the greatest effect on the reduction of biofilm viability (p < 0.0001). On the other hand, lactic acid production was reduced significantly with PerioGard^®, Noplak^® Max and Listerine^® Zero compared with the control (p < 0.0001). No significant differences were found among the mouthrinses with respect to the colony-forming unit counting (total microorganisms, total streptococci, mutans streptococci and lactobacilli) and extracellular polysaccharide production. Enamel demineralization was reduced significantly with PerioGard^®, Noplak^® Max and Malvatricin^® Plus compared with the control (p < 0.0001). Malva sylvestris has a comparable anti-caries effect to chlorhexidine mouthrinses.     

Caries activity and associated risk factors in elderly hospitalised population--15-months follow-up in French institutions

Only a few studies have been published concerning hospitalised elderly disabled people. Objectives: 1) to investigate the oral health status of elderly French patients hospitalised in the two main geriatric hospitals of Paris. 2) to describe the respective influences of general parameters (type of hospitalisation, pathologies and medication) on oral environment parameters. 3) to analyse the influences of these oral parameters on caries activity in Long-Term Care (LTCF) and in rehabilitation facilities (RF) patients and to study the incidence and the time-course of caries in these specific population. Subjects: 117 subjects (mean age=83.0 years, SD=7.8, range=64 to 102 years) were examined at baseline and 32 of the 50 LTCF subjects were reexamined 15-months later. Methods: The general parameters recorded were age, gender, type of hospitalisation, period of stay, removable prosthesis, general diseases, number of diagnoses, medications with hyposalivary side-effects. The oral environment parameters recorded were flow rate, buffer capacity, mutans streptococci and lactobacilli counts, measured at baseline by tests on stimulated saliva, and plaque index. Crown and root surfaces were recorded according to a modified caries activity index. Results: Among the polypathological subjects (85.5% of the population), the number of diseases ranged from 2 to 8. The LTCF patients had a significantly higher mean number of diagnoses (3.5; SD=1.5) than the RF patients (2.8; SD=1.4). 76.9% of patients were taking medications with hyposalivary side-effects. The stimulated flow rate ranged from 0.02 ml/min to 5 ml/min. Its mean was significantly lower for LTCF patients (0.67 ml/min; SD=0.51) than for RF patients (1.12 ml/min; SD=0.89). The plaque index was significantly higher in LTCF subjects and in patients with mental diseases. At baseline, 17,442 crown and root surfaces were examined. Flow rate was related to crown caries and buffer capacity to root caries. During the 15-months follow-up, the mean number of active root surfaces was significantly increased: from 0.148 (SD=0.116) at baseline vs. 0.250 (SD=0.174) at the second examination. Conclusions: The strongest relationship in the present study between oral parameters and caries activity was the negative relationship between buffer capacity and active root caries. This study confirms an association between the type of hospitalisation and both salivary parameters flow rate and plaque index. This investigation illustrates the critical need for hygiene and oral care, in this elderly disabled population.     

Influence of bite force and tongue pressure on oro-pharyngeal residue in the elderly

Objective: To investigate the influence of maximal bite force, maximal tongue pressure, number of mastications and swallowing on the oro‐pharyngeal residue in the elderly. Background: Oro‐pharyngeal residue in the elderly is an indication of dysphagia. Pharyngeal residue is especially critical as it may cause aspiration pneumonia, which is one of the major causes of death in elderly. Materials and methods: Videofluorographic recordings were performed on 14 elderly volunteers (six males, eight females, age range 65–93 years) without any history or symptoms of dysphagia. The subjects were instructed to consume 9 g of barium containing bread in two manners; free mastication and swallow (FMS: masticate and swallow freely), and limited mastication and swallow (LMS: swallow once after 30 chewing actions). The amount of oral and pharyngeal residue was evaluated using a 4‐point rating scale. Maximal occlusal force was measured by a pressure sensitive sheet, and maximal tongue pressure using a handy probe. Multiple regression analysis was performed to examine the influence of these items on the amount of oral and pharyngeal residue in FMS and LMS. Results: In FMS, age was found to be a factor which increased oral residue (p = 0.053), and the number of swallowing (p = 0.017) and the state of the prosthesis (p = 0.030) reduced the pharyngeal residue. In LMS, tongue pressure was a factor which reduced oral residue (p = 0.015) and increased pharyngeal residue (p = 0.008). Conclusion: It is suggested that in the elderly tongue pressure contributed to propulsion of the food bolus from oral cavity into the pharynx, and multiple swallowing contributed to the reduction in the amount of pharyngeal residue.     

Complete Genome Sequence of Streptococcus mutans GS-5, a Serotype c Strain

Streptococcus mutans, a principal causative agent of dental caries, is considered to be the most cariogenic among all oral streptococci. Of the four S. mutans serotypes (c, e, f, and k), serotype c strains predominate in the oral cavity. Here, we present the complete genome sequence of S. mutans GS-5, a serotype c strain originally isolated from human carious lesions, which is extensively used as a laboratory strain worldwide.     

Relationship of cariogenic bacteria levels with periodontal status and root surface caries in elderly Japanese

Objective: The relationship of the levels of cariogenic bacterial species with periodontal status and decayed root surfaces was investigated in elderly Japanese subjects. Methods: Three hundred and sixty‐eight individuals (each 75 years old) were examined for periodontal status (pocket depth, attachment loss), root surface caries and salivary levels of mutans streptococci (MS) and lactobacilli (LB). Results: Values >4 mm of attachment loss (rAL4) and for average attachment loss (aAL) of sites measured were significantly higher in subjects with LB than those without. Multiple regression analysis also showed a correlation between aAL and rAL4 values with the presence of LB (aAL p = 0.003; rAL4 p = 0.002). Further, multiple regression analysis of interacting factors regarding decayed root surfaces showed that LB carriers had a greater incidence of decayed root surface caries (p = 0.003), while MS and LB levels were correlated to the number of decayed root surfaces (LB p = 0.010; MS p = 0.026). Conclusion: Our results indicate that considerable attachment loss elevates the possibility of having LB, thus increasing the risk of root surface caries. It was also found that LB and MS measurements may be useful indicators of decayed root surfaces in elderly individuals with attachment loss.