Caries incidence and increments in community-living older adults with and without dementia

Objectives: The Oral Health of Older Adults with Dementia was instigated in the late 1990s to quantify and compare coronal and root caries incidence and increments in community‐living older Australians with and without dementia. Methods: A longitudinal design was used to conduct dental inspections at baseline and one‐year, for two groups of randomly selected community‐living older adults ‐ one group of 116 people with dementia and a comparison group of 116 people without dementia. Results: At one‐year there were 103 dementia and 113(112 dentate) non‐dementia participants. Coronal and root surface caries incidence was higher for dementia participants (p<0.05). Dementia participants had higher coronal and root caries adjusted caries increments (ADJCI) (p<0.01). Both coronal and root ADJCI were evident in half of dementia participants, compared with one‐quarter of non‐dementia participants. Dementia participants with higher coronal ADJCI were those who had visited the dentist since baseline, who were taking neuroleptics with high anticholinergic adverse effects, and whose carer had high carer burden score (p<0.01). Dementia participants with higher root ADJCI were those needing assistance with oral hygiene care and whose carers had difficulties with oral hygiene care (p<0.05). Baseline characteristics predictive in linear regression for: (1) coronal caries increments among all participants were ‐ dementia participants, those with cognitive testing scores indicative of moderate‐severe dementia, those with private health insurance; (2) root caries increments among all participants were ‐ dementia participants, and those who had 1 decayed/filled root surface at baseline. Among dementia participants, being male was the baseline characteristic predictive in logistic regression for coronal caries increments, and having 1 decayed coronal surface was the baseline characteristic predictive for root caries increments. Conclusions: Coronal and root caries incidence and increments were significantly higher in the community‐living older adults with dementia over the one‐year follow‐up period. Dementia participants had high levels of coronal and root caries increments; characteristics related to high caries increments included sex (males), dementia severity (moderate‐severe), high carer burden, oral hygiene care difficulties, use of neuroleptic medication (with high anticholinergic adverse effects) and previous experience of caries.     

The Effect of Salicylic Acid on Peroxidase Activity in Wheat Calli Cocultured with the Bunt Pathogen Tilletia caries

The effect of salicylic acid (SA) on peroxidase activity in wheat (Triticum aestivum L.) calli cocultured with the bunt pathogen Tilletia caries was studied. Fungal infection was shown to activate cytoplasmic peroxidase. SA suppressed total peroxidase activity but did not inhibit the peroxidase with pI 9.8. A novel chitin-specific peroxidase with pI 3.5 appeared after the SA treatment. The infection of SA-treated cells with Tilletia caries activated the isoenzymes with pI 3.5, 4.8, and 7.5 and stimulated their secretion into the culture medium. The ability of SA to control wheat peroxidase activity during pathogenesis is discussed. The important role of this control in plant defense responses to the bunt pathogen is emphasized.     

Non-invasive management of superficial root caries lesions in disabled and infirm patients

In disabled and infirm patients with limited, if any, capacity for independent oral self‐care, it is difficult to control progression of root caries lesions. Objective: To evaluate the effect of non‐restorative cariostatic treatment on progression of active superficial root caries lesions (n =56). Design: Pilot study. Setting: Department of Cariology, Institute of Odontology, Karolinska Institutet, Huddinge. Subjects: 15 physically‐dependent patients. Intervention: The patients were allotted to one of the following groups. Group 1, professional tooth cleaning and application of tap water flavoured with eucalyptus oil; Group 2, professional tooth cleaning and application of Cervitec, (1% chlorhexidine in thymol‐containing varnish), Group 3, professional tooth cleaning and application of Cervitec and Fluor Protector (varnish containing 0.1% fluoride). Every three months for 18 months, each subject received the treatment twice within a 10‐day interval. Measurements: The status of the 56 root caries lesions was evaluated every six months using a root caries index based on visual and tactile criteria. The examiners were blind to which treatment group the patients belonged. Results: In most subjects (14 out of 15), progression of root caries lesions was arrested. No statistically significant differences could be demonstrated between the three treatment groups. However, regardless of treatment regimen, there was a statistically significant difference between the greater number of subjects exhibiting no progression of root caries lesions and those with lesion progression, at 6 (p=0.022), 12 (p=0.006) and 18 months (p<0.001). Conclusion: This pilot study suggests that in disabled and infirm patients regular professional tooth cleaning with a fluoride containing paste, with or without supplementary varnishing with chlorhexidine‐thymol and/or fluoride can prevent further progression of existing superficial root caries lesions.     

Diacetylcurcumin: a new photosensitizer for antimicrobial photodynamic therapy in Streptococcus mutans biofilms

This study evaluated the effect of antimicrobial photodynamic therapy (aPDT) on S. mutans using diacetylcurcumin (DAC) and verified DAC toxicity. In vitro, S. mutans biofilms were exposed to curcumin (CUR) and DAC and were light-irradiated. Biofilms were collected, plated and incubated for colony counts. DAC and CUR toxicity assays were conducted with Human Gingival Fibroblast cells (HGF). In vivo, G. mellonella larvae were injected with S. mutans and treated with DAC, CUR and aPDT. The hemolymph was plated and incubated for colony counts. Significant reductions were observed when DAC and CUR alone were used and when aPDT was applied. HGF assays demonstrated no differences in cell viability for most groups. DAC and CUR reduced the S. mutans load in G. mellonella larvae both alone and with aPDT. Systematic toxicity assays on G. mellonella demonstrated no effect of DAC and CUR or aPDT on the survival curve.     

Genome sequence of Streptococcus mutans bacteriophage M102

Bacteriophage M102 is a lytic phage specific for serotype c strains of Streptococcus mutans, a causative agent of dental caries. In this study, the complete genome sequence of M102 was determined. The genome is 31,147 bp in size and contains 41 ORFs. Most of the ORFs encoding putative phage structural proteins show similarity to those from bacteriophages from Streptococcus thermophilus. Bioinformatic analysis indicated that the M102 genome contains an unusual lysis cassette, which encodes a holin and two lytic enzymes.     

低龄婴幼儿龋微生物群落的研究进展

低龄婴幼儿龋(early childhood caries,ECC)是影响全世界儿童最常见的疾病之一,然而龋病并不是由单一致龋细菌引起,而是由微生物、宿主、饮食和时间,即"龋病病因四因素"之间复杂的相互作用所引起,其中微生物因素起着主要作用。口腔微生物之间存在着一种稳定关系,与宿主保持着和谐的生态平衡,一旦受到某种特殊环境改变的影响,这种平衡则可能被打破。到目前为止,国内外关于ECC的微生物群落研究方法很多,结果不尽相同,因此了解ECC的组成及动态变化对于儿童龋病的预防和防治极其重要。本文就ECC微生物群落的研究进展作一详细综述。     

Brief communication: First evidence of LSAMAT in non-native Americans: Historic Senegalese from West Africa

To date, the distinctive dental wear pattern known as LSAMAT, or “lingual surface attrition of the maxillary anterior teeth,” has been documented in prehistoric samples from Brazil, Panama, and Puerto Rico only. However, new data from a historic Senegalese sample reveals the first example of this wear pattern outside the Americas. The Senegal LSAMAT is present in 45% of 22 adult crania, and is associated with a caries rate of 40% in 38 adults (6.7% of 534 permanent teeth). A correlation between LSAMAT and caries was also observed in the Latin American samples. In these cases, it was hypothesized that LSAMAT was caused by the specialized consumption of an abrasive, high carbohydrate food, such as manioc. Manioc is a common cultigen in Senegal; thus, it may have also caused the African LSAMAT. The chewing of sugar cane could have been an additional, contributing factor. Am J Phys Anthropol 102:141–146, 1997. © 1997 Wiley-Liss, Inc.     

Dental caries in nineteenth century Upper Canada

This study examines the presence of dental caries in a large sample of adult skeletons from the 19th century cemetery of St. Thomas' Anglican Church in Belleville, Ontario. The cemetery was used from 1821 to 1874. Caries prevalence and frequencies of diseased and missing teeth were calculated both by observing summary statistics of individual rates and by the total sample of teeth. Postmortem tooth loss is low in this sample and antemortem tooth loss is highest in first mandibular molars, all other molars and then premolars. Age at death, but not sex, was found to be significantly related to the overall Caries Rate while both age and sex were significantly associated with the Diseased-Missing Index. The increase in diseased and missing teeth in older individuals is expected while the sex difference is not explained by simple dietary factors. When compared to reports on British and American samples, caries and antemortem tooth loss in the St. Thomas' sample is most similar to a pre-1850 British group and higher than American samples. Although there is undoubtedly a complex of factors contributing to caries prevalence in this sample, more data are required from large historic samples, particularly from the American northeast and late 19th century Britain, to have a clearer understanding of the influence of diet, cultural, and environmental factors affecting caries rates in historic populations. Am J Phys Anthropol 104:71–87, 1997. © 1997 Wiley-Liss, Inc.     

健康与龋病口腔唾液中乳杆菌的发酵类群与表面性质

目的 研究口腔健康的成年人和龋病患者唾液中乳杆菌的发酵类群和表面性质。方法 糖酸以口腔健康的成年人和龋病患者为对象,取其早餐后2 h的无刺激全唾液分离乳杆菌,检验其对葡萄糖和葡萄糖酸钠发酵的情况;应用MATH（Microbiol Adhesion to Hydrocarbons）法测定菌体表面疏水性和电荷。结果 口腔健康的成年人与龋病患者唾液中乳杆菌各发酵类群的比例不同,前者表面疏水性和电荷比较高,后者比较低。结论 口腔健康的成年人和龋病患者唾液中乳杆菌的组成不同,表面性质也不同,特定种类的乳杆菌与龋病的发展相关。