In vitro Detection of Occlusal Caries on Permanent Teeth by a Visual, Light-Induced Fluorescence and Photothermal Radiometry and Modulated Luminescence Methods

The paradigm shift towards the non-surgical management of dental caries relies on the early detection of the disease. Detection of caries at an early stage is of unequivocal importance for early preventive intervention. OBJECTIVE: The aim of this in vitro study is to evaluate the performance of a visual examination using the International Caries Detection and Assessment System criteria (ICDAS), two quantitative light-induced fluorescence systems (QLF); Inspektor™ Pro and QLF-D Biluminator™ 2 (Inspektor Research Systems B.V., Amsterdam, The Netherlands) and a Photothermal Radiometry and Modulated Luminescence (PTR/LUM), The Canary System® (Quantum Dental Technologies, Toronto, Canada) on detection of primary occlusal caries on permanent teeth. METHODS: 60 teeth with occlusal surface sites ranging from sound to non-cavitated occlusal lesions ICDAS (0-4) were assessed with each detection method twice in a random order. Histological validation was used to compare methods for sensitivity, specificity, % correct and the area under receiver operating characteristic curve (AUC), at standard and optimum sound thresholds. Inter-examiner agreement and intra-examiner repeatability were measured using intraclass correlation coefficient (ICC). RESULTS: Inter-examiner agreement ranged between 0.48 (The Canary System®) and 0.96 (QLF-D Biluminator™2). Intra-examiner repeatability ranged 0.33-0.63 (The Canary System®) and 0.96-0.99 (QLF-D Biluminator™2). Sensitivity ranged 0.75-.096 while specificity ranged 0.43-0.89. AUC was 0.79 (The Canary System®); 0.87 (ICDAS); 0.90 63 (Inspektor™ Pro); and 0.94 (QLF-D Biluminator™2). CONCLUSION: ICDAS had the best combination of sensitivity and specificity followed by QLF-D Biluminator™ 2 at optimum threshold

Photo Inactivation of Streptococcus mutans Biofilm by Violet-Blue light

Among various preventive approaches, non-invasive phototherapy/photodynamic therapy is one of the methods used to control oral biofilm. Studies indicate that light at specific wavelengths has a potent antibacterial effect. The objective of this study was to determine the effectiveness of violet-blue light at 380-440 nm to inhibit biofilm formation of Streptococcus mutans or kill S. mutans. S. mutans UA159 biofilm cells were grown for 12-16 h in 96-well flat-bottom microtiter plates using tryptic soy broth (TSB) or TSB with 1 % sucrose (TSBS). Biofilm was irradiated with violet-blue light for 5 min. After exposure, plates were re-incubated at 37 °C for either 2 or 6 h to allow the bacteria to recover. A crystal violet biofilm assay was used to determine relative densities of the biofilm cells grown in TSB, but not in TSBS, exposed to violet-blue light. The results indicated a statistically significant (P < 0.05) decrease compared to the non-treated groups after the 2 or 6 h recovery period. Growth rates of planktonic and biofilm cells indicated a significant reduction in the growth rate of the violet-blue light-treated groups grown in TSB and TSBS. Biofilm viability assays confirmed a statistically significant difference between violet-blue light-treated and non-treated groups in TSB and TSBS. Visible violet-blue light of the electromagnetic spectrum has the ability to inhibit S. mutans growth and reduce the formation of S. mutans biofilm. This in vitro study demonstrated that violet-blue light has the capacity to inhibit S. mutans biofilm formation. Potential clinical applications of light therapy in the future remain bright in preventing the development and progression of dental caries

Photoinhibition of Streptococcus mutans Biofilm-Induced Lesions in Human Dentin by Violet-Blue Light

This in vitro study determined the effectiveness of violet-blue light on Streptococcus mutans (UA159) biofilm induced dentinal lesions. Biofilm was formed on human dentin specimens in a 96-well microtiter plate and incubated for 13 h in the presence of tryptic soy broth (TSB) or TSB supplemented with 1% sucrose (TSBS). Violet-blue light (405 nm) from quantitative light-induced fluorescence (QLFTM) was used to irradiate the biofilm. Supernatant liquid was removed, and the biofilm was irradiated continuously with QLF for 5 min twice daily with an interval of 6 h for 5 d, except with one treatment on the final day. Colony forming units (CFU) of the treated biofilm, changes in fluorescence (∆F; QLF-Digital BiluminatorTM), lesion depth (L), and integrated mineral loss (∆Z; both transverse microradiography) were quantified at the end of the fifth day. Statistical analysis used analysis of variance (ANOVA), testing at a 5% significance level. In the violet-blue light irradiated groups, there was a significant reduction (p < 0.05) of bacterial viability (CFU) of S. mutans with TSB and TSBS. Violet-blue light irradiation resulted in the reduction of ∆F and L of the dentinal surface with TSBS. These results indicate that violet-blue light has the capacity to reduce S. mutans cell numbers

Orange/Red Fluorescence of Active Caries by Retrospective Quantitative Light-Induced Fluorescence Image Analysis

This retrospective clinical study determined the association of caries activity and orange/red fluorescence on QLF images of surfaces that progressed to cavitation as determined by clinical visual examination. A random sample of QLF images from 565 children (5-13years) previously enrolled in a longitudinal study was selected. Buccal, lingual and occlusal surfaces’ images obtained after professional brushing at baseline and every 4 months over a 4-year period were analyzed for Red Fluorescence (RF). Surfaces that progressed (N=224) to cavitation according to International Caries Detection and Assessment System (ICDAS 0/1/2/3/4 to 5/6/filling) and surfaces that did not progress (N=486) were included. QA2 image analysis software outputs the percentage increase of the red/green components as ΔR and Area of ΔR (Area△R) at different thresholds. Mixed-model ANOVA was used to compare progressive and non-progressive surfaces to account for correlations of RF (ΔR and AreaΔR) between surfaces within a subject. The first analysis used the first observation for each surface or the first available visit if the surface was unerupted (baseline), while the second analysis used the last observation prior to cavitation for surfaces that progressed and last observation for surfaces that did not progress (final). There was a significant (p<0.05) association between RF and progression to cavitation at thresholds ΔR0, ΔR10, ΔR20, ΔR60, ΔR70, ΔR80, ΔR90 and ΔRMax at baseline and for ΔR0 and ΔR10 at final observation. Quantification of orange/red fluorescence may help to identify lesions that progress to cavitation. Future studies identifying microbiological factors causing orange/red fluorescence and its caries activity are indicated

Novel Approach in the Construction of Bioethanol-Producing Saccharomyces cerevisiae Hybrids

Za proizvodnju bioetanola iz lignoceluloznih hidrolizata potreban je proizvodni soj koji dobro podnosi prisutnost inhibitora rasta i fermentacije te veliku koncentraciju etanola. Stoga smo konstruirali hibridne diploide kvasca Saccharomyces cerevisiae međusobnim križanjem dvaju prirodnih izolata, Yllcl 7_E5 i UWOPS87-2421. Soj Yllcl 7_E5 izoliran je iz vina kao dobar proizvođač etanola, a soj UWOPS87-2421 izoliran je iz cvijeta kaktusa Opuntia megacantha i otporan je na inhibitore koji se mogu naći u lignoceluloznim hidrolizatima. Hibridni sojevi rasli su brže od ishodnih sojeva u odsutnosti i prisutnosti octene i levulinske kiseline te 2-furaldehida, koji se često nalaze kao inhibitori rasta u lignoceluloznim hidrolizatima, a pojačana ekspresija gena YAPI povećala je preživljenje testiranih sojeva. Također, pojedini su hibridni sojevi, iako potječu od dvaju istih ishodnih sojeva, pokazali različit fermentativni potencijal u testu proizvodnje C02, što upućuje na njihovu genetičku varijabilnost koja omogućava daljnju selekciju poželjnih svojstava. Iz naših se rezultata može zaključiti da se kombiniranjem konstrukcije hibridnih sojeva i metoda genetičkog inženjerstva mogu oplemeniti i razviti novi biotehnološki relevantni sojevi kvasca S. cerevisiae. Osim toga, utvrđeno je da je uspješnost ciljanja gena u prirodnim izolatima S. cerevisiae (Yllcl 7_E5a and UWOPS87-2421 a) daleko manja nego u laboratorijskim sojevima, a najčešći aberantni događaj bio je duplikacija ciljanog kromosoma.Bioethanol production from lignocellulosic hydrolysates requires a producer strain that tolerates both the presence of growth and fermentation inhibitors and high ethanol concentrations. Therefore, we constructed heterozygous intraspecies hybrid diploids of Saccharomyces cerevisiae by crossing two natural S. cerevisiae isolates, YIIc17_E5 and UWOPS87-2421, a good ethanol producer found in wine and a strain from the flower of the cactus Opuntia megacantha resistant to inhibitors found in lignocellulosic hydrolysates, respectively. Hybrids grew faster than parental strains in the absence and in the presence of acetic and levulinic acids and 2-furaldehyde, inhibitors frequently found in lignocellulosic hydrolysates, and the overexpression of YAP1 gene increased their survival. Furthermore, although originating from the same parental strains, hybrids displayed different fermentative potential in a CO2 production test, suggesting genetic variability that could be used for further selection of desirable traits. Therefore, our results suggest that the construction of intraspecies hybrids coupled with the use of genetic engineering techniques is a promising approach for improvement or development of new biotechnologically relevant strains of S. cerevisiae. Moreover, it was found that the success of gene targeting (gene targeting fidelity) in natural S. cerevisiae isolates (YIIc17_E5α and UWOPS87-2421α) was strikingly lower than in laboratory strains and the most frequent off-targeting event was targeted chromosome duplication

How to Intervene in the Caries Process: Dentin Caries in Primary Teeth

For an ORCA/EFCD consensus, this review systematically assessed available evidence regarding interventions performed and materials used to manage dentin carious lesions in primary teeth. A search for systematic reviews (SRs) and randomized clinical trials (RCTs) with a follow-up of at least 12 months after intervention was performed in PubMed, LILACS, BBO, and the Cochrane Library. The risk of bias tool from the Cochrane Collaboration and the PRISMA Statement were used for assessment of the included studies. From 101 screened articles, 2 SRs and 5 RCTs, which assessed the effectiveness of interventions in terms of pulp vitality and success of restoration, and 10 SRs and 1 RCT assessing the success of restorative materials were included. For treatments involving no carious tissue removal, the Hall technique showed lower treatment failure for approximal carious lesions compared to complete caries removal (CCR) and filling. For the treatment of deep carious lesions, techniques involving selective caries removal (SCR) showed a reduction in the incidence of pulp exposure. However, the benefit of SCR over CCR in terms of pulp symptoms or restoration success/failure was not confirmed. Regarding restorative materials, preformed metal crowns (PMCs) used to restore multisurface lesions showed the highest success rates compared to other restorative materials (amalgam, composite resin, glass ionomer cement, and compomer), and in the long term (12–48 months) these were also less likely to fail. There is limited evidence supporting the use of PMCs to restore carious lesions with single cavities. Among nonrestorative options, silver diammine fluoride was significantly more effective in arresting caries than other treatments for treating active carious lesions of different depths. Considerable heterogeneity and bias risk were observed in the included studies. Although heterogeneity observed among the studies was substantial, the trends were similar. In conclusion, less invasive caries approaches involving selective or no caries removal seem advantageous in comparison to CCR for patients presenting with vital, symptomless, carious dentin lesions in primary teeth. There is evidence in favor of PMCs for restoring multisurface carious lesions in primary molars

How to Intervene in the Caries Process in Older Adults: A Joint ORCA and EFCD Expert Delphi Consensus Statement

Aim: To provide recommendations for dental clinicians for the management of dental caries in older adults with special emphasis on root caries lesions. Methods: A consensus workshop followed by a Delphi consensus process were conducted with an expert panel nominated by ORCA, EFCD, and DGZ boards. Based on a systematic review of the literature, as well as non-systematic literature search, recommendations for clinicians were developed and consented in a two-stage Delphi process. Results: Demographic and epidemiologic changes will significantly increase the need of management of older adults and root caries in the future. Ageing is associated with a decline of intrinsic capacities and an increased risk of general diseases. As oral and systemic health are linked, bidirectional consequences of diseases and interventions need to be considered. Caries prevention and treatment in older adults must respond to the patient’s individual abilities for self-care and cooperation and often involves the support of caregivers. Systemic interventions may involve dietary counselling, oral hygiene instruction, the use of fluoridated toothpastes, and the stimulation of salivary flow. Local interventions to manage root lesions may comprise local biofilm control, application of highly fluoridated toothpastes or varnishes as well as antimicrobial agents. Restorative treatment is often compromised by the accessibility of such root caries lesions as well as the ability of the senior patient to cooperate. If optimum restorative treatment is impossible or inappropriate, longterm stabilization, e.g., by using glass-ionomer cements, and palliative treatments that aim to maintain oral function as long and as well as possible may be the treatment of choice for the individual

How to Intervene in the Caries Process in Older Adults: A Joint ORCA and EFCD Expert Delphi Consensus Statement

Aim: To provide recommendations for dental clinicians for the management of dental caries in older adults with special emphasis on root caries lesions. Methods: A consensus workshop followed by a Delphi consensus process were conducted with an expert panel nominated by ORCA, EFCD, and DGZ boards. Based on a systematic review of the literature, as well as non-systematic literature search, recommendations for clinicians were developed and consented in a two-stage Delphi process. Results: Demographic and epidemiologic changes will significantly increase the need of management of older adults and root caries in the future. Ageing is associated with a decline of intrinsic capacities and an increased risk of general diseases. As oral and systemic health are linked, bidirectional consequences of diseases and interventions need to be considered. Caries prevention and treatment in older adults must respond to the patient's individual abilities for self-care and cooperation and often involves the support of caregivers. Systemic interventions may involve dietary counselling, oral hygiene instruction, the use of fluoridated toothpastes, and the stimulation of salivary flow. Local interventions to manage root lesions may comprise local biofilm control, application of highly fluoridated toothpastes or varnishes as well as antimicrobial agents. Restorative treatment is often compromised by the accessibility of such root caries lesions as well as the ability of the senior patient to cooperate. If optimum restorative treatment is impossible or inappropriate, long-term stabilization, e.g., by using glass-ionomer cements, and palliative treatments that aim to maintain oral function as long and as well as possible may be the treatment of choice for the individual

How to Intervene in the Caries Process in Children: A Joint ORCA and EFCD Expert Delphi Consensus Statement

This paper provides recommendations for dentists for the treatment of dental caries in children, with an emphasis on early childhood caries (ECC), primary teeth, and occlusal surfaces in permanent teeth. A consensus workshop followed by an e-Delphi consensus process was conducted with an expert panel nominated by the European Organization for Caries Research (ORCA) and European Federation of Conservative Dentistry (EFCD)/German Association of Conservative Dentistry (DGZ) boards. Based on 3 systematic reviews and a nonsystematic literature search, recommendations were developed. The caries decline has led to a more polarized disease distribution in children and adolescents along social gradients which should be taken into account when managing the caries process at all levels, such as the individual, the group, or a population. The control or reduction of caries activity is the basis for successful caries management. In children, caries management requires adequate daily oral hygiene and fluoride application via toothpaste, ensured by caregivers, and especially for ECC prevention an emphasis on sugar intake reduction is needed. These noninvasive interventions are also suitable to arrest or control initial or even cavitated dentine caries lesions in the absence of irreversible pulpitis. Fluoride varnish or silver diammine fluoride can be added as supplementary agents. In pits and fissures, composite resin materials can be used as preventive sealants and for defect-oriented minimally invasive restorations. In primary molars, preformed metal crowns are more successful than multisurface fillings, especially in caries-active patients. With persisting high caries activity, multiple lesions, and limited cooperation, caries control should consist of robust measures with high success rates, even including extraction in selected cases. This applies especially to treatments performed under general anesthesia

Should Lecture Recordings Be Mandated in Dental Schools? Two Viewpoints

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153701/1/jddj0022033720168012tb06235x.pd