Influence of moisture and plaque on the performance of a laser fluorescence device in detecting caries lesions in primary teeth

The aim of this study was to evaluate the influence of dental plaque and moisture on performance of a laser fluorescence device in detecting occlusal and proximal caries lesions in primary teeth. Fifty-five occlusal and 58 proximal sites on primary molars were evaluated using a DIAGNOdent pen (LFpen) device. For the drying time study, the evaluations were performed in: (I) moist teeth; (II) teeth dried for 3 s, or (III) dried for 15 s. For the plaque study, the evaluations were done in sites: (I) without plaque; (II) with plaque, and (III) after cleaning. Evaluation of the teeth sections in stereomicroscope was the reference standard method. LF pen values, sensitivity, specificity, and accuracy were compared. The values obtained after 15 s of drying were higher than those obtained with moist teeth or dried for 3 s at both occlusal and proximal surfaces. However, there was no change in the performance in detecting caries lesions. With regard to the presence of plaque, there was no significant change in the readings of the device, but specificity was decreased in occlusal surfaces with plaque. At proximal surfaces, however, no significant differences were observed. In conclusion, the moisture conditions do not influence significantly the performance of the LFpen, but the presence of plaque can affect its performance in detecting occlusal caries lesions in primary teeth.

Glycan-binding specificities of Streptococcus mutans and Streptococcus sobrinus lectin-like adhesins

Since the adhesion of bacteria to the tooth surface is a prerequisite for dental plaque and subsequent caries development, a promising caries preventive strategy could be to block the lectin-glycan-mediated adherence of cariogenic bacteria. The aim of the study was to evaluate potential differences in glycan-binding specificities of two Streptococcus mutans strains (DSM 20523 and DSM 6178) and Streptococcus sobrinus (DSM 20381). A competitive enzyme-linked lectin-binding assay was used to identify the binding specificities of isolated bacterial surface lectins. Blotting of the microbial proteins on neoglycoprotein-coated PVP membranes enabled a qualitative protein analysis of all specific bacterial lectins. Different glycan-binding sites could be identified for the S. mutans strains in comparison to S. sobrinus. An earlier reported glycan-binding specificity for terminal galactose residues could be confirmed for the S. mutans strains. For the S. sobrinus strain, more than one glycan-binding specificity could be found (oligomannose and terminal sialyl residues). Each of the tested strains showed more than one surface lectin responsible for the specific lectin-binding with varying molecular weight (S. mutans, 90/155 kDa and S. sobrinus, 35/45 kDa). The established experimental setup could be used as future standard procedure for the identification of bacterial lectin-derived binding specificities. The findings from this study might serve as basis for the design of an individual 'glycan cocktail' for the competitive inhibition of lectin-mediated adhesion of mutans streptococci to oral surfaces.

Oral microbiota in Swiss adolescents

OBJECTIVES: The purpose of the study was to determine the prevalence of different oral microbes in gingival plaque samples and in samples from the dorsum of the tongue in a Swiss adolescent population. MATERIALS AND METHODS: Ninety-nine adolescents between 15 and 18 years were enrolled. Plaque index, bleeding on probing (BOP), the periodontal screening index, and decayed missed filled tooth (DMFT) index were recorded. Samples from subgingival plaque and swabs from the tongue were analyzed by the Checkerboard DNA-DNA hybridization method. Additionally, counts of Streptococus mutans and Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were determined by real-time PCR. RESULTS: Periodontitis was not diagnosed in any of the subjects but all of them presented signs of gingival inflammation displaying a mean BOP of 28%. Ten (10.1%) subjects were tested positive for P. gingivalis, each 22 (22.2%) for A. actinomycetemcomitans and T. forsythia, (47.5%) for T. denticola. T. denticola and S. mutans showed a high affinity to the gingival plaque, whereas T. forsythia was often detected from the dorsum of the tongue. DMFT was associated with S. mutans counts, and BOP correlated with counts of P. gingivalis and T. denticola. CONCLUSIONS: The present data indicate that: (a) gingivitis but not periodontitis is a common finding among Swiss adolescents, and (b) bacteria associated with periodontitis were frequently detected in the subgingival dental plaque and on the dorsum of the tongue in Swiss adolescents with gingivitis. CLINICAL RELEVANCE: Although gingivitis was a frequent finding in Swiss adolescents, periodontitis was not detected in this population. The dorsum of the tongue appears to represent an important reservoir for periodontopathic bacteria.

The impact of denture related disease on the oral microbiome of denture wearers

Advances in healthcare over the last 100 years has resulted in an ever increasing elderly population. This presents greater challenges for adequate systemic and oral healthcare delivery. With increasing age there is a natural decline in oral health, leading to the loss of teeth and ultimately for some having to wear denture prosthesis. It is currently estimated that approximately one fifth of the UK and US populations have some form of removable prosthesis. The microbiology of denture induced mucosal inflammation is a pivotal factor to consider in denture care management, similar to many other oral diseases of microbial influence, such as caries, gingivitis and periodontitis. Dentures support the growth of microbial biofilms, structures commonly known as denture plaque. Microbiologically, denture stomatitis (DS) is a disease primarily considered to be of yeast aetiology, with the literature disproportionately focussed on Candida spp. However, the denture surface is capable of carrying up to 1011 microbes per milligram, the majority of which are bacteria. Thus it is apparent that denture plaque is more diverse than we assume. There is a fundamental gap in our understanding of the bacterial composition of denture plaque and the role that they may play in denture related disease such as DS. This is categorised as inflammation of the oral mucosa, a disease affecting around half of all denture wearers. It has been proposed that bacteria and fungi interact on the denture surface and that these polymicrobial interactions lead to synergism and increased DS pathogenesis. Therefore, understanding the denture microbiome composition is the key step to beginning to understand disease pathogenesis, and ultimately help improve treatments and identify novel targets for therapeutic and preventative strategies. A group of 131 patients were included within this study in which they provided samples from their dentures, palatal mucosa, saliva and dental plaque. Microbes residing on the denture surface were quantified using standard Miles and Misra culture technique which investigated the presence of Candida, aerobes and anaerobes. These clinical samples also underwent next generation sequencing using the Miseq Illumina platform to give a more global representation of the microbes present at each of these sites in the oral cavity of these denture wearers. This data was then used to compare the composition and diversity of denture, mucosal and dental plaque between one another, as well as between healthy and diseased individuals. Additional comparisons included denture type and the presence or absence of natural teeth. Furthermore, microbiome data was used to assess differences between patients with varying levels of oral hygiene. The host response to the denture microbiome was investigated by screening the patients saliva for the presence and quantification of a range of antimicrobial peptides that are associated with the oral cavity. Based on the microbiome data an in vitro biofilm model was developed that reflected the composition of denture plaque. These biofilms were then used to assess quantitative and compositional changes over time and in response to denture cleansing treatments. Finally, the systemic implications of denture plaque were assessed by screening denture plaque samples for the presence of nine well known respiratory pathogens using quantitative PCR. The results from this study have shown that the bacterial microbiome composition of denture wearers is not consistent throughout the mouth and varies depending on sample site. Moreover, the presence of natural dentition has a significant impact on the microbiome composition. As for healthy and diseased patients the data suggests that compositional changes responsible for disease progression are occurring at the mucosa, and that dentures may in fact be a reservoir for these microbes. In terms of denture hygiene practices, sleeping with a denture in situ was found to be a common occurrence. Furthermore, significant shifts in denture microbiome composition were found in these individuals when compared to the denture microbiome of those that removed their denture at night. As for the host response, some antimicrobial peptides were found to be significantly reduced in the absence of natural dentition, indicating that the oral immune response is gradually impaired with the loss of teeth. This study also identified potentially serious systemic implications in terms of respiratory infection, as 64.6% of patients carried respiratory pathogens on their denture. In conclusion, this is the first study to provide a detailed understanding of the oral microbiome of denture wearers, and has provided evidence that DS development is more complex than simply a candidal infection. Both fungal and bacterial kingdoms clearly play a role in defining the progression of DS. The biofilm model created in this study demonstrated its potential as a platform to test novel actives. Future use of this model will aid in greater understanding of host: biofilm interactions. Such findings are applicable to oral health and beyond, and may help to identify novel therapeutic targets for the treatment of DS and other biofilm associated diseases.

Educação e motivação em saúde bucal: prevenindo doenças e promovendo saúde em pacientes sob tratamento ortodôntico

INTRODUÇãO: os cirurgiões-dentistas têm a responsabilidade de prevenir doenças, minimizar riscos e promover saúde. Os pacientes também precisam ser despertados sobre o seu papel nos cuidados com a saúde bucal. No caso de pacientes em tratamento ortodôntico, é particularmente difícil manter uma higiene bucal satisfatória devido à presença de bandas, fios e ligaduras. Torna-se, então, indispensável a instituição de métodos preventivos de motivação e orientação para o controle mecânico da placa dentária. OBJETIVO: verificar os efeitos de ações educativas, preventivas e motivacionais sobre a saúde bucal de pacientes em tratamento ortodôntico fixo. MéTODOS: os participantes receberam gratuitamente dentifrício e escova dental durante todo o estudo e instruções sobre higiene bucal foram fornecidas e reforçadas no decorrer dos 6 meses da pesquisa. Foram realizados exames clínicos baseline e após 6, 12 e 24 semanas, para verificação dos índices de Placa, Gengival e Sangramento. RESULTADOS: as condições de saúde bucal dos participantes, que inicialmente eram insatisfatórias, melhoraram significativamente no decorrer do estudo, considerando-se todos os índices. As ações preventivas, educativas e motivacionais realizadas foram estatisticamente eficazes na melhora da saúde bucal dos pacientes ortodônticos. CONCLUSõES: a promoção de saúde e a prevenção de doenças devem fazer parte do atendimento que os ortodontistas direcionam aos seus pacientes, sendo que a orientação e motivação quanto aos cuidados com a saúde bucal devem estar presentes antes e durante o tratamento.

Analysis of the periodontal status of patients with mandibular-bonded retainers

PURPOSE: This clinical study evaluated the periodontal status of patients with bonded retainers as compared to a non-treated control group. METHODS: Forty dental students were included in the sample and divided into the following two groups: 1) a test group of 20 subjects that, after orthodontic treatment, have been bonded retainer users for at least 2 years and 2) a control group of 20 patients that never experienced orthodontic treatment nor used any bonded retainer. The region associated with the retainer in the test group and the lower canine-to-canine region in the control group were examined according to the following clinical parameters: plaque index (PI), bleeding on probing (BOP), gingival recession (GR), clinical attachment level (CAL) and probing depth (PD). RESULTS: No differences were observed for GR or BOP (P>0.05). In contrast, the test group showed higher values of CAL and PD at proximal sites when compared to controls (P<0.05). In addition, IP was significantly increased at buccal and lingual sites (P<0.05). CONCLUSION: The placement of orthodontic bonded retainers negatively affected periodontal health, resulting in increased PI, PD and CAL.

Prevalência e severidade de gengivite em escolares de 7 a 14 anos: condições locais associadas ao sangramento à sondagem

O objetivo deste estudo foi coletar dados sobre a prevalência e severidade de gengivite em uma amostra de crianças em idade escolar, bem como sua relação com possíveis fatores de risco locais. Duzentos e seis indivíduos foram examinados, sendo 107 meninos e 99 meninas, com idades entre 7 e 14 anos; foram coletados dados referentes ao índice de placa (IP), índice gengival (IG) e profundidade clínica de sondagem (PCS). Entre os parâmetros clínicos observados, as médias referentes a PCS, IP e IG encontradas foram de 1,58 + 0,46, 1,12 + 0,49 e 0,89 + 0,32, respectivamente. Noventa e cinco indivíduos (46,1%) apresentaram um quadro de gengivite leve e 111 (53,9%), de gengivite moderada. No geral, os indivíduos do sexo masculino apresentaram estatisticamente maior quantidade de placa bacteriana e maior inflamação do tecido gengival que indivíduos do sexo feminino. A presença de inflamação gengival foi encontrada em todos os indivíduos examinados. A severidade de inflamação nos dentes permanentes esteve diretamente relacionada à quantidade de placa e ao sangramento à sondagem.

Oral cavity is not a reservoir for Helicobacter pylori in infected patients with functional dyspepsia

Helicobacter pylori infection is very prevalent in Brazil, infecting almost 65% of the population. The aim of this study was to evaluate the presence of this bacterium in the oral cavity of patients with functional dyspepsia (epigastric pain syndrome), establish the main sites of infection in the mouth, and assess the frequency of cagA and vacA genotypes of oral H. pylori. All 43 outpatients with epigastric pain syndrome, who entered the study, were submitted to upper gastrointestinal endoscopy to rule out organic diseases. Helicobacter pylori infection in the stomach was confirmed by a rapid urease test and urea breath tests. Samples of saliva, the tongue dorsum and supragingival dental plaque were collected from the oral cavity of each subject and subgingival dental plaque samples were collected from the patients with periodontitis; H. pylori infection was verified by polymerase chain reaction using primers that amplify the DNA sequence of a species-specific antigen present in all H. pylori strains; primers that amplify a region of urease gene, and primers for cagA and vacA (m1, m2, s1a, s1b, s2) genotyping. Thirty patients harbored H. pylori in the stomach, but it was not possible to detect H. pylori in any oral samples using P1/P2 and Urease A/B. The genotype cagA was also negative in all samples and vacA genotype could not be characterized (s-m-). The oral cavity may not be a reservoir for H. pylori in patients with epigastric pain syndrome, the bacterium being detected exclusively in the stomach.

Cross-Sectional Microhardness of Human Enamel Subjected to Erosive, Cariogenic or Combined Erosive/Cariogenic Challenges

This in situ study evaluated the interaction between caries and erosion processes. In the first phase, enamel specimens were subjected to erosion without dental plaque (EO) or to erosion with plaque (EP); in the second phase, they were subjected to erosion plus cariogenic challenge (EC) or cariogenic challenge (CO), both with plaque accumulation. Cross-sectional hardness data (10-330 mu m depth) were tested using ANOVA (alpha = 0.05). EO and EP showed surface softening to 10 mu m depth. CO and EC produced subsurface lesions, of similar depth (up to 220 mu m), with CO showing higher integrated loss of hardness than EC, indicating that cariogenic and erosive challenges did not have an additive effect. Copyright (C) 2010 S. Karger AG, Basel

Effectiveness of 0.50% and 0.75% chlorhexidine dentifrices in orthodontic patients: A double-blind and randomized controlled trial

Introduction: In this double-blind and randomized controlled trial, we analyzed whether a lower concentration of chlorhexidine in dentifrices could reduce the risk of tooth staining without compromising its effectiveness in controlling gingivitis, bleeding, and dental plaque. Methods: Volunteers with fixed orthodontic appliances were randomly divided into 3 groups: control, 1100 ppm F, NaF (n = 27); experimental, chlorhexidine 0.50% (n = 27); and experimental, chlorhexidine 0.75% (n = 27). At baseline, and after 6 and 12 weeks, clinical examinations were carried out. Staining, calculus, gingivitis, bleeding, and dental plaque data were analyzed with Friedman tests to evaluate intragroup changes over time. To detect intergroup differences after 12 months, the data were evaluated with Kruskal-Wallis tests. Dunn tests were used in both situations for necessary post-hoc analyses. Results: The groups were statistically similar for the stain, calculus, and plaque indexes, but there were statistically significant differences for the gingival and bleeding indexes. During the experimental periods, gingivitis and bleeding scores improved in all 3 groups. Only the 0.75% chlorhexidine dentifrice significantly increased the stain index, although most patients did not notice the stains. The intergroup comparison showed a statistically significant better performance of the experimental groups regarding the gingival and bleeding indexes. Conclusions: This study suggests that the use of dentifrices with lower concentration of chlorhexidine can reduce the risk of tooth staining without compromising its effectiveness in controlling gingivitis and bleeding in orthodontic patients. (Am J Orthod Dentofacial Orthop 2009; 136: 651-6)

Effectiveness of motivational interviewing at improving oral health: a systematic review

OBJECTIVE : To analyze the effectiveness of motivational interviewing (MI) at improving oral health behaviors (oral hygiene habits, sugar consumption, dental services utilization or use of fluoride) and dental clinical outcomes (dental plaque, dental caries and periodontal status). METHODS : A systematic search of PubMed, LILACS, SciELO, PsyINFO, Cochrane and Google Scholar bibliographic databases was conducted looking for intervention studies that investigated MI as the main approach to improving the oral health outcomes investigated. RESULTS : Of the 78 articles found, ten met the inclusion criteria, all based on randomized controlled trials. Most studies (n = 8) assessed multiple outcomes. Five interventions assessed the impact of MI on oral health behaviors and nine on clinical outcomes (three on dental caries, six on dental plaque, four on gingivitis and three on periodontal pockets). Better quality of evidence was provided by studies that investigated dental caries, which also had the largest population samples. The evidence of the effect of MI on improving oral health outcomes is conflicting. Four studies reported positive effects of MI on oral health outcomes whereas another four showed null effect. In two interventions, the actual difference between groups was not reported or able to be recalculated. CONCLUSIONS : We found inconclusive effectiveness for most oral health outcomes. We need more and better designed and reported interventions to fully assess the impact of MI on oral health and understand the appropriate dosage for the counseling interventions.

Role of biofilms in the oral health of animals

In humans the importance of biofilms in disease processes is now widely recognised together with the difficulties in treating such infections once established. One of the earliest and certainly most studied biofilm in humans is that of dental plaque which is responsible for two of the most prevalent human infections, namely dental caries and periodontal disease. However, comparable studies of dental plaque in animals are relatively limited, despite the fact that similar infections also occur, and in the case of farm animals there is an associated economic impact. In addition, biofilms in the mouths of animals can also be detrimental to human health when transferred by animal bites. As a result, an understanding of both the microbial composition of animal plaque biofilms together with their role in animal diseases is important. Through the use of modern molecular studies, an insight into the oral microflora of animals is now being obtained and, to date, reveals that despite differences in terms of microbial species and relative proportions occurring between humans and animals, similarities do indeed exist. This information can be exploited in our efforts to both manage and treat infections in animals arising from the presence of an oral biofilm. This Chapter describes our current understanding of the microbial composition of animal plaque, its role in disease and how oral hygiene measures can be implemented to reduce subsequent infection.

Helicobacter pylori transiently in the mouth may participate in the transmission of infection

Helicobacter pylori infection is associated with peptic ulcer and gastric carcinoma. The oral cavity may be a reservoir for H. pylori; however, the results of studies on this subject are controversial. We employed single-step and nested polymerase chain reactions (PCR) to detect the presence of the vacA, ureA and 16S rDNA genes of H. pylori in the stomach, saliva and dental plaque of 30 subjects. The results were confirmed by sequencing. Nested 16S rDNA and ureA amplification was achieved in 80% of gastric, 30% of saliva and 20% of dental plaque specimens. Sequencing of 10, seven and four 16S rDNA products from stomach, saliva and dental plaque, respectively, showed > 99% identity with H. pylori. Sequencing of the other four oral cavity PCR products showed similarity with Campylobacter and Wolinella species. Additionally, the vacA genotype identified in the samples of different sites was the same within a given subject.H. pylori may be found in the oral cavity of patients with gastric infection, thus it could be a source of transmission. However, results obtained with detection methods based only on PCR should be interpreted with caution because other microorganisms that are phylogenetically very close to H. pylori are also present in the mouth.

In vitro antibacterial action of Tetraclean, MTAD and five experimental irrigation solutions

P>Aim To investigate the antibacterial effect of Tetraclean, MTAD and five experimental irrigants using both direct exposure test with planktonic cultures and mixed-species in vitro biofilm model. Methodology Tetraclean, MTAD and five experimental solutions that were modifications of existing formulae including MTAD + 0.01% cetrimide (CTR), MTAD + 0.1% CTR, MTAC-1 (Tween 80 replaced by 0.01% CTR in MTAD), MTAC-2 (Tween 80 replaced by 0.1% CTR) and MTAD-D (MTAD without the Tween 80 and no CTR added) were used as disinfectants in the experiments. In the direct exposure test, a suspension of Enterococcus faecalis was mixed with each of the solutions. After 0.5, 1, 3 and 10 min, an inactivator was added and the number of surviving bacteria was calculated. A mixed-species biofilm from subgingival plaque bacteria was grown in brain heart infusion broth in anaerobic conditions on synthetic hydroxyapatite discs. Two-week-old biofilms were exposed to the solutions for 0.5, 1 and 3 min. The samples were observed by confocal laser scanning microscopy after bacterial viability staining. The scans were quantitatively analysed, and the volume of killed cells of all cells was calculated for each medicament. Results Tetraclean and MTAC-2 (0.1% CTR) killed planktonic E. faecalis in < 30 s. Complete killing of bacteria required 1 min by MTAC-1, 3 min by MTAD + 0.1% CTR and 10 min by MTAD, MTAD-D and MTAD + 0.01% CTR. In the biofilm test, there were significant differences in microbial killing between the different solutions and times of exposure (P < 0.005). MTAC-2 showed the best performance, killing 71% of the biofilm bacteria in 3 min, followed by MTAC-1 and Tetraclean. MTAD and the three MTAD modifications demonstrated the lowest antibacterial activity. Conclusion Tetraclean was more effective than MTAD against E. faecalis in planktonic culture and in mixed-species in vitro biofilm. CTR improved the antimicrobial properties of the solutions, whereas Tween 80 seemed to have a neutral or negative impact on their antimicrobial effectiveness.

Avaliação da saúde bucal e anomalias dentárias em pacientes tratados com leucemia na infância e adolescência

Objetivo: o objetivo deste estudo foi avaliar as condições de saúde bucal e a ocorrência de anomalias dentárias em crianças tratadas para leucemia linfoblástica aguda (LLA) no Serviço de Oncologia Pediátrica (SOP) do Hospital de Clínicas de Porto Alegre (HCPA), comparadas com um grupo crianças saudáveis. Amostra: foram selecionadas 56 crianças com diagnóstico de LLA e analisadas as presenças de anomalias dentárias e os índices CPO-D (cariado, perdido, obturado-dente), IPV (índice de placa visível), ISG (índice de sangramento gengival) e fluxo salivar. As crianças tratadas apresentaram uma média de idade, na época do diagnóstico da LLA, de 5,3 ± 2,6, e 11,8 ± 4,2 na avaliação, sendo 32 masculinos e 24 femininos. Os pacientes tratados para LLA foram divididos em três grupos: crianças tratadas somente com quimioterapia, com quimio e radioterapia, e com quimio, radio e transplante de medula óssea. Resultados: os resultados revelaram 80,4% de anomalias dentárias nas crianças tratadas, ou seja, 45 destas apresentaram pelo menos uma alteração, e o grupo de pacientes tratados com quimio, radio e submetidos ao transplante de medula óssea foi o que revelou a maior média de anormalidades dentárias por indivíduo (15,37 ± 15,03), não ocorrendo diferença estatística entre os gêneros. As crianças tratadas para LLA obtiveram CPO-D de 1,9 ± 4,0, ISG de 26,5%, IPV de 72,0%, e índice de fluxo salivar médio de 0,19 mL/min criança. Já o grupo de crianças sadias apresentou CPO-D de 1,52 ± 3,5, ISG de 11,1%, IPV de 53,8% e índice de fluxo salivar médio de 0,27 mL/min. Conclusão: o tratamento para a cura da LLA provoca um aumento significativo no número de anomalias dentárias, sendo mais freqüente nos pacientes menores de cinco anos de idade, principalmente nos pacientes submetidos a quimio e radioterapia associadas ao transplante de medula óssea, o que requer, por parte do cirurgião-dentista, intervenções clínicas diferenciadas e cuidadosas nestes pacientes, tendo-se em vista também os índices aumentados de ISG e IPV. As alterações sofridas pelas glândulas salivares durante o tratamento não são permanentes sob o aspecto do fluxo salivar, que retorna à normalidade. A orientação e o acompanhamento adequados destes pacientes por parte da equipe de saúde bucal podem mantê-los com o índice de CPO-D dentro dos padrões preconizados pela Organização Mundial de Saúde.