Caries clinical trial of a remineralising toothpaste in radiation patients

Objectives: The purpose of this study was to determine the efficacy and safety of a specially formulated remineralising toothpaste in controlling caries in a high‐risk population: head and neck radiation patients. Design: The study compared the performance of the remineralising toothpaste with a conventional fluoride dentifrice using double‐blind randomisation. Materials and methods: Test products: The products compared contained equivalent quantities of fluoride (1100 p.p.m.). The dual‐phase remineralising toothpaste, Enamelon^®, also delivered soluble calcium and phosphate ions, essential components of teeth, from separate phases. Both groups had all caries restored at baseline and used a fluoride rinse daily. Subjects: Fifty‐seven subjects who received radiation to the head and neck causing saliva hypofunction, entered the study, while 44 completed the 10–12 month visit. Measurements: Examinations included coronal and root caries using the Pitts Diagnostic Criteria, salivary flow rate, plaque and gingival indices and microbiological counts over a 1‐year period. Results: The average net increment per year for root caries per subject was 0.04 (±.052) in subjects completing the study using the remineralising toothpaste and 1.65 (±0.51) for root caries in subjects completing the study using the conventional fluoride dentifrice. The difference was statistically significant (p = 0.03), suggesting lower net root surface increment/year for the remineralising toothpaste relative to the conventional toothpaste. No significant differences were noted on coronal surfaces. Conclusion: The results indicate that the remineralising toothpaste provides a significant benefit in preventing and remineralising root caries in high‐risk patients.     

Remineralisation study of artificial root caries lesions after fluoride treatment. An in vitro study using electric caries monitor and transversal micro-radiography

Aims: To evaluate and compare remineralisation of root caries lesions after in vitro treatment with various fluoride (F) agents using an Electric Caries Monitor (ECM) and Transversal Micro‐Radiography (TMR). Materials: Permanent human teeth were extracted and root surface specimens were sectioned, prepared (n = 35), and randomly allocated into seven different experimental groups (groups 1–7). Methods: Root surfaces were demineralised in an acidified gel (pH = 5.0) for 3 weeks followed by various F treatments and stored in a standardised remineralising solution at 37°C for 6 weeks. The root surfaces were treated twice daily with different dentifrice slurries for 2 min, either with a neutral placebo dentifrice without F (group 5); or a neutral sodium fluoride (NaF) 1400 p.p.m. F dentifrice (group 1); or a neutral 1250 p.p.m. F dentifrice (group 6); or an acid dentifrice (pH 4.7) with 1400 p.p.m. F containing amine fluoride (AmF) (groups 3 and 4) or a 1250 p.p.m. (pH 4.7) AmF dentifrice (group 6). In groups 1, 2, 5, 6, and 7, the root surfaces were additionally rinsed for 2 min with a neutral non‐F placebo solution. In groups 3 and 4, rinsing were performed for 2 min with an acid (pH 4.7) 250 p.p.m. F solution, containing 125 p.p.m. F as AmF and 125 p.p.m. F as potassium fluoride (KF), once or twice per day respectively. ECM was used to measure electrical resistance on root surfaces at baseline and after 3 and 6 weeks respectively. TMR technique was used to measure and compare root surface lesion depths and mineral loss. Results: Six weeks daily treatment with a dentifrice slurry containing AmF followed by rinsing with a combination of equal amounts of AmF and KF solution twice a day showed a statistical significant higher ECM values compared with the other groups. TMR data measuring lesion depths and mineral loss reduction supported the results of the ECM findings. Conclusions: Daily application of a dentifrice slurry containing 1400 p.p.m. F as AmF combined with twice daily rinsing with a 250 p.p.m. F solution containing equal amount of AmF and KF significantly remineralise primary root caries lesions in vitro. ECM and TMR are valuable complementary methods in order to analyse the remineralisation processes.     

Oral mucous membrane flora in patients using saliva substitutes

Salivary substitutes are sometimes valuable for elderly people and radiotherapy patients, and may be used indefinitely. It is possible that this change in the ecology may effect the oral flora. Objective: To analyse the presence of micro‐organisms on oral mucous membranes during use of saliva substitutes. Design: Cross‐over single‐blind study. Setting: Clinic for Maxillofacial Surgery, Malmö University Hospital and Department of Oral Microbiology, Malmö University. Subjects: 19 patients with low salivary secretion who had been radiated for cancer in the head and neck region. Intervention Two saliva substitutes: linseed extract and a carboxymethyl cellulose preparation (Salinum and MAS‐84) were used for 3 week periods. Measurements: Microbial samples taken, processed and analysed. Results: No differences were observed when comparing baseline values with the results after the saliva substitutes and no significant differences between the use of different agents. Conclusion: The study suggests that use of linseed extract and carboxymethyl cellulose preparation during periods of weeks does not influence flora commonly related to caries, periodontitis or infections in the oral mucous membranes.     

Enhanced adhesion of Streptococcus mutans to hydroxyapatite after exposure to saliva

Streptococcus mutans cells form robust biofilms on human teeth and are strongly related to caries incidents. Hence, understanding the adhesion of S. mutans in the human oral cavity is of major interest for preventive dentistry. In this study, we report on atomic force microscopy–based single‐cell force spectroscopy measurements of S. mutans cells to hydroxyapatite surfaces. We observe for almost all measurements a significant difference in adhesion strength for S. mutans as well as for Staphylococcus carnosus cells. However, the increase in adhesion strength after saliva exposure is much higher for S. mutans cells compared to S. carnosus cells. Our results demonstrate that S. mutans cells are well adapted to their natural environment, the oral cavity. This ability promotes the biofilm‐forming capability of that species and hence the production of caries‐provoking acids. In consequence, understanding the fundamentals of this mechanism may pave a way towards more effective caries‐reducing techniques.     

The Copenhagen Oral Health Senior Cohort: design, population and dental health

Gerodontology 2010; doi: 10.1111/j.1741‐2358.2010.00383.x The Copenhagen Oral Health Senior Cohort: design, population and dental health Background: In order to study the way old age influence oral health, the Copenhagen Oral Health Senior Cohort (COHS) has been established. Objectives: To describe the design, measurement procedures, and baseline values for COHS including spatial distribution of restorations and dental caries as well as reasons for non‐participation. Materials and methods: Seven hundred and eighty‐three individuals aged 65 years or older, from a total of 1918 invited elderly people, underwent an interview regarding oral health‐related behaviour and a clinical oral examination including measurement of unstimulated whole saliva flow rate. Results: Twelve percent of the COHS was edentulous. The number of dental restorations was higher for women compared to men; however, men had more caries than women. Coronal caries was most frequent on mesial and distal surfaces and on the maxillary incisors and canines; root caries was most frequent on labial surfaces and evenly distributed within the dentition. Only 41% of all invited elderly people accepted the invitation, with old age and poor health being the primary reasons for non‐participation. Conclusion: The baseline values for COHS show that a substantial proportion of the participants had retained a natural dentition and that dental caries was prevalent with the anterior maxillary teeth being most affected.     

Relationship between root caries and cardiac dysrhythmia

doi: 10.1111/j.1741‐2358.2010.00367.x
Relationship between root caries and cardiac dysrythmia Background: Cardiac dysrhythmia are frequently found in the elderly population because of conduction system disease and ageing. Recent reports have suggested that dental caries and periodontal disease are predictors of coronary heart events. However, this hypothesis remains largely unproven. Objective: This study investigated the relationship between root caries and cardiac dysrhythmia in an elderly population. Subjects and methods: Among 600 subjects, 233 who were dentate at baseline underwent a baseline examination and subsequent annual investigations, including an oral examination and a 12‐lead electrocardiogram, for a 4‐year period. Analysis of covariance (ancova) was used to assess the number of sites with root caries between subjects with mean C‐reactive protein (CRP) serum level of <3.0 mg/l and those with the mean CRP serum level ≥3.0 mg/l. Logistic regression analysis was performed to assess relationship between root caries and cardiac dysrhythmia. Results: A high mean CRP serum level group had a significantly higher number of sites with root caries than a low CRP group (p < 0.001). Number of sites with root caries events was significantly associated with cardiac dysrhythmia among non‐smokers (odds ratio, 5.84; p = 0.040). These results suggest that root caries is related to the incidence of dysrhythmias in non‐smokers. Conclusions: We conclude that non‐smoking elders with root caries lesions are at an elevated risk for dysrhythmias.     

Effect of repeated cycles of chemical disinfection on the roughness and hardness of hard reline acrylic resins

doi:10.1111/j.1741‐2358.2009.00282.x
Effect of repeated cycles of chemical disinfection on the roughness and hardness of hard reline acrylic resins Objective: The aim of this study was to assess the effect of repeated cycles of five chemical disinfectant solutions on the roughness and hardness of three hard chairside reliners. Methods: A total of 180 circular specimens (30 mm × 6 mm) were fabricated using three hard chairside reliners (Jet; n = 60, Kooliner; n = 60, Tokuyama Rebase II Fast; n = 60), which were immersed in deionised water (control), and five disinfectant solutions (1%, 2%, 5.25% sodium hypochlorite; 2% glutaraldehyde; 4% chlorhexidine gluconate). They were tested for Knoop hardness (KHN) and surface roughness (μm), before and after 30 simulated disinfecting cycles. Data was analysed by the factorial scheme (6 × 2), two‐way analysis of variance (anova ), followed by Tukey’s test. Results: For Jet (from 18.74 to 13.86 KHN), Kooliner (from 14.09 to 8.72 KHN), Tokuyama (from 12.57 to 8.28 KHN) a significant decrease in hardness was observed irrespective of the solution used on all materials. For Jet (from 0.09 to 0.11 μm) there was a statistically significant increase in roughness. Kooliner (from 0.36 to 0.26 μm) presented a statistically significant decrease in roughness and Tokuyama (from 0.15 to 0.11 μm) presented no statistically significant difference after 30 days. Conclusions: This study showed that all disinfectant solutions promoted a statistically significant decrease in hardness, whereas with roughness, the materials tested showed a statistically significant increase, except for Tokuyama. Although statistically significant values were registered, these results could not be considered clinically significant.     

Development and evaluation of two root caries controlling programmes for home-based frail people older than 75 years

Objectives: (i) Initially, to devise and examine the validity of a system for determining lesion activity on root surfaces, and (ii) compare the effectiveness of two preventive programmes in controlling root caries in elderly people using the devised system. Materials and methods: (i) Four clinical variables: texture, contour, location and colour of root caries lesions were selected to evaluate lesion activity. The intraexaminer reproducibility of the scoring system was assessed on 28 elderly patients. The accuracy was assessed on 10 of these persons using an impression material (Clinpro, 3M ESPE). (ii) Of total, 215 homebound 75+ year olds were randomly assigned to one of three groups: group 1, once a month a dental hygienist brushed the teeth of the participants and applied Duraphat vanish to active root caries lesions. The participants in groups 2 and 3 received 5000 and 1450 ppm F‐toothpaste, respectively, to use twice a day. This study included an interview, a baseline examination and a final follow‐up examination after 8 months. Results: (i) Intraexaminer reproducibility of the root caries scoring system was 0.86 (Kappa). The sensitivity and specificity was 0.86 and 0.81. (ii) Data from those 189 (88%) who completed the study disclosed that there were no inter‐group differences at the baseline examination concerning relevant conditions. At the end of the study, the root caries status of participants in groups 1 and 2 had improved significantly when compared with group 3 (p < 0.02). No significant difference was observed between groups 1 and 2 (p = 0.14). Conclusion: The data suggest that the root caries scoring system is reliable. Both the intervention programmes controlled root caries development; the hygienist in eight of 10 persons, the 5000 ppm F‐toothpaste in seven of 10. In contrast, five of 10 participants who only brushed with 1450 ppm F‐toothpaste had root caries progression.     

Effect of glypican‐1 gene on the pulp cells during the reparative dentine process

GPC‐1 (glypican‐1) is a cell surface heparan sulfate proteoglycan that acts as a co‐receptor for heparin‐binding growth factors and members of the TGF‐β (transforming growth factor beta‐1) family. The function of cell‐surface proteoglycans in the reparative dentine process has been under investigation. Gpc‐1 was detected with similar frequency as tgf‐β1 in the cDNA library using mRNA from the odontoblast‐like cell‐enriched pulp of rat incisors. The aim of this study was to test our hypothesis that gpc‐1 may be related to reparative dentine formation. We examined the expression of this gene during the reparative dentine process, as well as the effect of gpc‐1 on odontoblast‐like cell differentiation using siRNA (small interfering RNA) to down‐regulate gpc‐1 expression. Immunohistological examination showed that GPC‐1 was expressed in pulp cells entrapped by fibrodentine and odontoblast‐like cells as well as TGF‐β1. The mRNAs for gpc‐1, ‐3 and ‐4, except for gpc‐2, were expressed during odontoblast‐like cell differentiation in pulp cells. The relative levels of gpc‐1 mRNA were increased prior to the differentiation stages and were decreased during the secretory and maturation stages of pulp cells. Down‐regulation of gpc‐1 expression resulted in a 3.9‐fold increase in tgf‐β1 expression in pulp cells and a 0.3‐fold decrease in dspp (dentine sialophosphoprotein) expression compared with control. These results suggested that gpc‐1 and tgfβ‐1 expression are necessary for the onset of differentiation, but should be down‐regulated before other molecules are implicated in the formation of reparative dentine. In conclusion, gpc‐1 expression in odontoblast‐like cells is associated with the early differentiation but not with the formation of reparative dentine.     

The role of the saliva antioxidant barrier to reactive oxygen species with regard to caries development

Objectives: The aim of this study was to evaluate the role of the antioxidant barrier in the saliva of children with caries, and its impact on the colonization of cariogenic bacteria.

Methods: This is a cross-sectional study of 81 children aged 1–5 years. Antioxidant levels and salivary bacterial profiles were measured. Patients were divided into two groups as follows: initial stage decay, termed non-cavitated (1–2 in International Caries Detection and Assessment System (ICDAS)), and extensive decay, termed cavitated lesions (5–6 in ICDAS). The control group includes children without caries.

Results: The linear regression model demonstrated that the GSH, GSSG, GSH/GSSG, and total antioxidant capacity levels are influenced (P?P?Discussion: Our results indicate that the high levels of antioxidants in saliva increase significantly in children in line with the salivary cariogenic bacterial profiles and caries progression.     

Activity assessment of root caries lesions with thermal and near‐IR imaging methods

The purpose of this study was to evaluate thermal and near‐infrared (NIR) reflectance imaging methods for the assessment of the activity of root caries lesions. In addition, changes in the lesion structure were monitored with polarization sensitive optical coherence tomography (PS‐OCT). Artificial bovine and natural root caries lesions were imaged with PS‐OCT, and their dehydration rate was measured with thermal and NIR cameras. The lesion activity of the natural root caries samples was also assessed by two clinicians by conventional means according to ICDAS II guidelines. The thickness of the highly mineralized transparent surface layer measured using PS‐OCT increased and the area enclosed by the time‐temperature curve, ΔQ, measured with thermal imaging decreased significantly with longer periods of remineralization in simulated dentin lesions, but the NIR reflectance intensity differences, ΔI, failed to show any significant relationship with the degree of remineralization. The PS‐OCT algorithm for the automated assessment of remineralization successfully detected the highly mineralized surface layer on both natural and simulated lesions. Thermal imaging provided the most accurate diagnosis of root caries lesion activity. These results demonstrate that thermal imaging and PS‐OCT may be ideally suited for the nondestructive root caries lesion activity during a clinical examination.

     

Relationship of stimulated whole saliva cortisol level with the severity of a feeling of dry mouth in menopausal women

doi: 10.1111/j.1741‐2358.2010.00403.x Relationship of stimulated whole saliva cortisol level with the severity of a feeling of dry mouth in menopausal women Objectives: To evaluate the relationship of stimulated whole saliva cortisol level with the severity of a feeling of dry mouth (DM) in menopausal women. Background: A feel of DM is a major complaint for many elderly individuals and strongly associated with the menopause. The exact mechanisms that mediate sensation of DM in menopausal women have not been firmly established. Methods: A case–control study was carried out on 104 selected menopausal women with/without a feeling of DM, conducted at the Clinic of Oral Medicine, Tehran University of Medical Sciences. Xerostomia Inventory (XI) score was used as an index of DM severity. Stimulated whole saliva cortisol concentration (stimulated by chewing standard‐sized paraffin for 60 s) was measured by ELISA. Statistical analysis by Student’s t‐test and Spearman correlation was used. Results: The mean cortisol concentration of saliva, but not saliva cortisol output, was significantly higher in the cases than in the controls. There was significant positive correlation between XI score and concentration (r = 0.357, p = 0.000) or output (r = 0.223, p = 0.017) of stimulated whole saliva cortisol. Conclusions: It appears that stimulated whole saliva cortisol is high in menopausal women with a feeling of DM.     

Comparison of antioxidant enzymes in saliva of elderly smokers and non-smokers

Objectives: This study was designed to compare the levels of copper/zinc superoxide dismutase (Cu/Zn SOD), peroxidase (POx) and glutathione peroxidase (GSH‐Px) in saliva of smokers and those in saliva of non‐smokers. Methods: Unstimulated saliva samples were collected from 88 elderly males (65 years old or over) who visited a private dental clinic. Forty‐four subjects were current smokers (more than 20 cigarettes daily for at least 30 years) and 44 were non‐smokers. The levels of salivary thiocyanate, Cu/Zn SOD, GSH‐Px, and POx activity were measured using standard procedures. Results: The mean levels of salivary thiocyanate (SCN^?) and SOD were significantly higher (p < 0.01) in the smoking group than in the non‐smoking group, whereas the specific activity levels of POx and GSH‐Px were significantly higher (p < 0.05) in the non‐smoking group than in the smoking group. Significant correlation coefficients were found between the levels of SCN^? and SOD (r = 0.37, p < 0.001). In the non‐smoking group, a significant positive association was found between specific activity of POx and age (r = 0.33, p < 0.05). Conclusion: Measurement of SCN^? and Cu/Zn SOD in human saliva might be useful for estimating the level of oxidative stress caused by cigarette smoke. Despite increased H₂O₂ level as a defense system induced by SOD, detoxification of H₂O₂ might be deteriorated in the oral cavity of elderly smokers.     

Characterization of polymicrobial biofilms obtained from saliva or carious lesions in dentin

Abstract

This study aimed to compare the formation of polymicrobial biofilms using carious dentin or saliva as inoculum for application in in vitro microbiological studies on caries research. For biofilm growth, combined samples of infected dentin or saliva from three donors were used. The biofilms were grown on glass coverslips, under a regimen of intermittent exposure (6?h day^?1) to 1% sucrose for 4?days. Total bacterial loads, as well as specific aciduric bacteria and mutans streptococci loads were quantified and correlated with biofilm acidogenicity and susceptibility to chlorhexidine. The data were evaluated using the Student’s-t, Mann Whitney and Kruskal-Wallis tests. The two biofilms showed similar microbial loads (total bacteria, aciduric bacteria and mutans streptococci) on day 4, and high acidogenicity after 48?h and were susceptible to chlorhexidine at different time intervals. In conclusion, both dentin and saliva can be used as an inoculum in in vitro studies of processes related to biofilm formation.     

Effect of saliva viscosity on the co-aggregation between oral streptococci and Actinomyces naeslundii

doi: 10.1111/j.1741‐2358.2011.00595.x Effect of saliva viscosity on the co‐aggregation between oral streptococci and Actinomyces naeslundii Background: The co‐aggregation of oral bacteria leads to their clearance from the oral cavity. Poor oral hygiene and high saliva viscosity are common amongst the elderly; thus, they frequently suffer from pneumonia caused by the aspiration of oral microorganisms. Objectives: To examine the direct effect of saliva viscosity on the co‐aggregation of oral streptococci with actinomyces. Materials and methods: Fifteen oral streptococcal and a single actinomyces strain were used. Co‐aggregation was assessed by a visual assay in phosphate buffer and a spectrophotometric assay in the same buffer containing 0–60% glycerol or whole saliva. Results: Nine oral streptococci co‐aggregated with Actinomyces naeslundii ATCC12104 in the visual assay and were subsequently used for the spectrophotometric analysis. All tested strains displayed a decrease in co‐aggregation with increasing amounts of glycerol in the buffer. The co‐aggregation of Streptococcus oralis with A. naeslundii recovered to baseline level following the removal of glycerol. The per cent co‐aggregation of S. oralis with A. naeslundii was significantly correlated with the viscosity in unstimulated and stimulated whole saliva samples (correlation coefficients: ?0.52 and ?0.48, respectively). Conclusion: This study suggests that saliva viscosity affects the co‐aggregation of oral streptococci with actinomyces and that bacterial co‐aggregation decreases with increasing saliva viscosity.     

Medication in elderly people: its influence on salivary pattern,signs and symptoms of dry mouth

doi:10.1111/j.1741‐2358.2009.00293.x
Medication in elderly people: its influence on salivary pattern, signs and symptoms of dry mouth Objective: To compare stimulated and non‐stimulated salivary flow, pH, buffering capacity and presence of signs and symptoms of hyposialie and xerostomia in elderly patients, with senile dementia using medication and healthy elderly subjects not using medication. Methods: Forty individuals (mean age: 68.5 years) were divided into two groups, according to the use (G1) or non‐use (G2) of medication and the presence (G1) or absence (G2) of senile dementia. Data with reference to the general health condition, use of medication and the patient’s complaints were collected during anamnesis. Clinical examination identified signs associated with hyposialie and xerostomia. Stimulated and non‐stimulated saliva flow, pH and buffering capacity were verified. Results: The stimulated saliva flow in both groups was below normal parameters. The drugs used by individuals in G1 showed xerostomic potential. Individuals with a higher consumption of xerostomic medication presented with dry and cracked lips. A significant negative relationship was found between drugs consumption and the buffering capacity (p < 0.001), and the resting saliva flow rate (p = 0.002). Conclusion: The use of medication increases the chance that an elderly person may present signs related to xerostomia and alterations in stimulated saliva flow and buffering capacity.     

Brief communication: A pilot study: Smooth surface early caries (caries incipiens) detection with kavo diagnodent in historical material

In many odontological studies concerning archeological material, there is no analysis of early caries lesions (caries incipiens) that manifest as a carious spot. At this stage of caries, the enamel is still hard, and thus, it is impossible to diagnose caries by visual methods. We assessed the usefulness of the DIAGNODent pen (DD laser) in analyzing noncavity lesions on the smooth surface sites of crowns from historical populations. Twenty‐seven individuals were examined: 18 from Radom (Poland), and nine from Tell Masaikh and Terqa (Syria). A total of 562 teeth were characterized. The series represented different climatic zones, but were dated from the similar period, 18th to 19th century AD. We used four diagnostic techniques: visual, DD laser, radiographic, and histological as the gold standard. DD laser showed that the mean values of healthy enamel in both series did not exceed 15 units. The mean values of smooth and rough spots in the Syrian population were significantly higher than those from Poland. This study showed that all the noncarious spots from the Radom series did not exceed 30 units. In the Syrian samples, this limit was higher at 44 units. These results were confirmed by histology and radiography. The DD laser provided good results in detecting dentine carious lesions in historical material, but its efficiency in diagnosing early caries (caries incipiens) remains uncertain based on the presented series. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.     

Proteases and nucleases involved in the biphasic digestion process of the brown marmorated stink bug,Halyomorpha halys (Hemiptera: Pentatomidae)

Management of the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), an invasive, agricultural pest in the United States, has presented significant challenges. This polyphagous insect uses both extra‐oral and gut‐based digestion thwarting protein‐ or nucleotide‐based control strategies. The objective of this study was to biochemically characterize the digestive enzymes (proteases and nucleases) from the saliva, salivary gland and the gut of H. halys. Enzyme profiles for the two tissues and saliva radically differ: The pH optimum for proteases in the gut was six, with cysteine proteases predominant. In contrast, the alkaline pH optima for protease activity in the salivary gland (8–10) and saliva (7) reflected abundant serine protease and cathepsin activities. RNase enzymes were most abundant in saliva, while dsRNase and DNase activities were higher in the salivary gland and saliva compared to those in the gut. These very different enzyme profiles highlight the biphasic digestive system used by this invasive species for efficient processing of plant nutrients. Knowledge of H. halys digestive physiology will allow for counteractive measures targeting digestive enzymes or for appropriate protection of protein‐ or nucleotide‐based management options targeting this pest.