Proteomic profile of the acquired enamel pellicle of children with early childhood caries and caries-free children.

Acquired enamel pellicle plays an important role in the pathogenesis of early childhood caries (ECC), working as a protective interface between the tooth and the oral cavity. The aim of this cross-sectional in vivo proteomic study was to compare the acquired enamel pellicle protein profile of 3-5-year-old children with ECC (n = 10) and caries-free children (n = 10). Acquired enamel pellicle samples were collected and processed for proteomic analysis (nLC-ESI-MS/MS). In total, 241 proteins were identified. Basic salivary proline-rich protein 1 and 2, Cystatin-B, and SA were found only in the caries free group. When comparing caries free and ECC groups, lower protein levels were found in the caries free group for hemoglobin subunit beta, delta, epsilon, gamma-2, globin domain-containing protein and gamma-1, neutrophil defensin 3, serum albumin, protein S100-A8, and S100-A9. The proteins histatin-1, statherin, salivary acidic proline-rich phosphoprotein ½, proline-rich protein 4, submaxillary gland androgen-regulated protein 3B, alpha-amylase 1 and 2B were found at higher levels in the caries free group. The exclusive and the proteins found at higher levels in the caries free group might have protective functions that play a role in the prevention of caries, besides providing important insights to be evaluated in future studies for the possible development of new therapeutic strategies for ECC.

Saliva proteomic profile of early childhood caries and caries-free children.

OBJECTIVE: Saliva plays an important antimicrobial role and it is related to the pathogenesis of early childhood caries (ECC). The aim of this study was to compare the proteomic profile of unstimulated saliva of children aged 3-5 years who had ECC and caries-free (CF) children. MATERIALS AND METHODS: After the saliva collection from 20 children (ECC: n = 10; CF: n = 10), the samples were processed for proteomic analysis on a mass spectrometer. RESULTS: 1638 proteins were identified, of which 355 were present in both groups. A total of 579 proteins were exclusively identified in the CF group and included Leucine-rich alpha-2-glycoprotein, Protein S100-A5, Protein S100-A8 and Mucin-2. Moreover, 704 proteins were exclusively identified in the ECC group, including Enamelin. The differential expression analysis revealed that 112 proteins were up-regulated in the CF group. Among these proteins, we highlighted Hemoglobin subunit gamma-1 (343-fold increase), gamma-2 (336-fold increase) and alpha (40-fold increase). CONCLUSIONS: The proteomic profile of the saliva varied substantially between the groups. Hemoglobin subunit gamma-1, gamma-2 and alpha may play a protective role in children with ECC. These proteins should be evaluated in future studies, because they may be possible good candidates to be included in anti-caries dental products.

Usefulness and satisfaction of a digital learning tool for caries detection using ICDAS / Utilidade e satisfação de uma ferramenta digital de aprendizado para detecção de cárie utilizando ICDAS

Objective: this study aimed evaluate the usefulness and satisfaction of a digital learning tool (DLT) using ICDAS (International caries detection and assessment system) created for learning and training visual detection of carious lesions in a non-controlled setting. Material and Methods: the DLT containing 60 pictures of sound and carious surfaces was distributed through social media and professional associations, aiming at both dentists and dental students. Analysis was based on data collected through a personal, professional and satisfaction questionnaire and Google Analytics. Results: a total of 2300 users accessed the DLT and 1517 completed it, filling out the questionnaires. Users required 2.29 sessions to accomplish the DLT in an average time of 15 min and 14 seconds each. The satisfaction questionnaire showed that 84.8% of users found in the DLT exactly what they expected and 91.8% found it useful. Around 88.4% of users found that the DLT helped in discussion of ICDAS with colleagues and 88.9% with superiors; 88.3% found that the DLT provided immediate learning results. The DLT was most useful to dental students (83.7% of users), and overall satisfaction was 86%. Conclusion: users found the DLT useful for learning and training visual detection of carious lesions using ICDAS, and general satisfaction was high. (AU)

Objetivo: o objetivo deste estudo foi avaliar a utilidade e a satisfação de uma ferramenta digital de aprendizado (FDA) utilizando o ICDAS (International caries detection and assessment system), criada para aprender e treinar a detecção visual desse índice de forma virtual. Material e Métodos: a FDA contendo 60 fotos de superfícies hígidas e cariadas foi distribuída por meio de mídias sociais, visando profissionais e estudantes de odontologia. A análise baseou-se nos dados recolhidos através de um questionário de satisfação da experiência e Google Analytics. Resultados: um total de 2.300 usuários acessaram a FDA e 1.517 a completaram até os questionários. Os usuários precisaram de 2,29 sessões para realizá-la em um tempo médio de 15 min e 14 segundos. O questionário de satisfação mostrou que 84,8% dos usuários encontraram exatamente o que esperavam e 91,8% a acharam útil. Cerca de 88,4% dos usuários acreditaram que a FDA ajudou na discussão do ICDAS com colegas e 88,9% com superiores; 88,3% acharam que foi fornecido resultados de aprendizagem imediatos. A FDA foi mais útil para estudantes de odontologia (83,7% dos usuários) e a satisfação geral foi de 86%. Conclusão: os usuários acharam a FDA útil para aprender e treinar a detecção visual de lesões cariosas utilizando o ICDAS. A satisfação geral alcançada foi considerada alta. (AU)

Knowledge and attitudes related to erosive tooth wear of professional wine tasters: a cross-sectional study / Conhecimentos e atitudes relacionadas ao desgaste dentário erosivo de provadores de vinho profissionais: um estudo transversal

Objective: this study aimed to evaluate knowledge and attitudes of professional wine tasters about erosive tooth wear. Material and Methods: two questionnaires were applied to 56 wine tasters during the 25th National Evaluation of Wines - Safra 2017 in Bento Gonçalves, Rio Grande do Sul. Descriptive data analysis and the Fisher's exact test were performed (p < 0.05). Results: for the analysis, 56 volunteers aged 25-76 years were included. Most of the volunteers reported attending dentist once a year (55.35%) and their teeth become sorer after ingesting liquids or acid foods (32.14%) over time. The majority (82.14%) believe wine tasting may have teeth effects and have already heard about erosive tooth wear (51.78%). However, when asked about symptomatology, more than half (53.57%) reported not to know. Brushing teeth immediately after ingesting something (37.5%) and increasing the brushing frequency (33.92%) were the most cited treatment options. The habit of using mouthwash solutions was significantly associated with the professionals age (p = 0.039). Conclusion: the volunteers reported a high intake of acid substances and, although most of them reported to consult dentist regularly and have already heard about erosive tooth wear, knowledge about this condition is still limited among these professionals. (AU)

Objetivo: o objetivo desse estudo foi avaliar o conhecimento e as atitudes de provadores de vinho profissionais relacionadas ao desgaste dentário erosivo. Material e Métodos: dois questionários foram aplicados a 56 provadores de vinho durante a 25ª Avaliação Nacional de Vinhos - Safra 2017 no município de Bento Gonçalves, Rio Grande do Sul. Foi realizada a análise descritiva dos dados e o teste Exato de Fisher (p < 0.05). Resultados: na análise foram incluídos 56 voluntários com idade entre 25 e 76 anos. A maioria dos voluntários relatou frequentar o dentista uma vez por ano (55,35%) e que seus dentes, com o passar do tempo, tornaram-se mais doloridos ao ingerir líquidos ou alimentos ácidos (32,14%). Mais da metade (82,14%) acreditam que as provas de vinho podem causar algum efeito sobre os dentes e já ouviram falar em desgaste dentário erosivo (51,78%). Porém, quando questionados sobre a sintomatologia, a maioria (53,57%) afirmou não ter conhecimento. Escovar os dentes imediatamente após ingerir algo (37,5%) e aumentar a frequência de escovação (33,92%) foram as opções mais compreendidas como tratamento. Utilizar soluções para bochecho esteve significativamente associado à idade dos profissionais (p=0,039). Conclusão: provadores de vinho profissionais relataram alta ingestão de substâncias ácidas e, embora a maioria consulte pelo menos uma vez por ano o dentista e já tenha ouvido falar a respeito do desgaste dentário erosivo, o conhecimento sobre essa condição ainda é limitado entre esses profissionais. (AU)

Augmented Vision for Dental Students' Education in Detecting Proximal Carious Lesions on Bitewing Radiographs: A Randomized Controlled Trial.

This two-arm, parallel, randomized controlled trial aimed to assess the effect of augmented vision (AV, using interactive color overlays) on the education of dental students in detecting proximal carious lesions on bitewing radiographs compared to black-and-white textbook-like illustrations. Forty-eight preclinical third-year dental students were randomized using a random number generator into two learning groups: test (AV, allowing interaction with color-highlighted carious lesions, n = 24) and control (showing the native radiograph and a black-and-white illustration displaying the carious lesion, n = 24). First, students had 2 weeks to assess 50 bitewings (lesion prevalence on the tooth level: 54.5%) in the test or control. Due to the nature of the intervention, participants could not be blinded toward the intervention. After that, they were asked to detect lesions on 10 independent bitewings and to assess lesion extent (outer/inner enamel; outer/middle/inner dentin). The reference test was constituted by two experienced dentists. No significant differences in accuracy (test 0.84 [95% CI: 0.79, 0.88]; control 0.83 [0.78, 0.87]), AUC (test 0.82 [0.81, 0.84]; control 0.81 [0.80, 0.83]) and F1 score (test 0.79 [0.75, 0.82]; control 0.77 [0.72, 0.81]) were observed between groups. Students of both groups showed difficulties in differentiating enamel from dentin carious lesions. While AV was reported to be motivating by students, it did not increase their accuracy.

Segmentation of Dental Restorations on Panoramic Radiographs Using Deep Learning.

Convolutional Neural Networks (CNNs) such as U-Net have been widely used for medical image segmentation. Dental restorations are prominent features of dental radiographs. Applying U-Net on the panoramic image is challenging, as the shape, size and frequency of different restoration types vary. We hypothesized that models trained on smaller, equally spaced rectangular image crops (tiles) of the panoramic would outperform models trained on the full image. A total of 1781 panoramic radiographs were annotated pixelwise for fillings, crowns, and root canal fillings by dental experts. We used different numbers of tiles for our experiments. Five-times-repeated three-fold cross-validation was used for model evaluation. Training with more tiles improved model performance and accelerated convergence. The F1-score for the full panoramic image was 0.7, compared to 0.83, 0.92 and 0.95 for 6, 10 and 20 tiles, respectively. For root canals fillings, which are small, cone-shaped features that appear less frequently on the radiographs, the performance improvement was even higher (+294%). Training on tiles and pooling the results thereafter improved pixelwise classification performance and reduced the time to model convergence for segmenting dental restorations. Segmentation of panoramic radiographs is biased towards more frequent and extended classes. Tiling may help to overcome this bias and increase accuracy.

Self-Supervised Learning Methods for Label-Efficient Dental Caries Classification.

High annotation costs are a substantial bottleneck in applying deep learning architectures to clinically relevant use cases, substantiating the need for algorithms to learn from unlabeled data. In this work, we propose employing self-supervised methods. To that end, we trained with three self-supervised algorithms on a large corpus of unlabeled dental images, which contained 38K bitewing radiographs (BWRs). We then applied the learned neural network representations on tooth-level dental caries classification, for which we utilized labels extracted from electronic health records (EHRs). Finally, a holdout test-set was established, which consisted of 343 BWRs and was annotated by three dental professionals and approved by a senior dentist. This test-set was used to evaluate the fine-tuned caries classification models. Our experimental results demonstrate the obtained gains by pretraining models using self-supervised algorithms. These include improved caries classification performance (6 p.p. increase in sensitivity) and, most importantly, improved label-efficiency. In other words, the resulting models can be fine-tuned using few labels (annotations). Our results show that using as few as 18 annotations can produce ≥45% sensitivity, which is comparable to human-level diagnostic performance. This study shows that self-supervision can provide gains in medical image analysis, particularly when obtaining labels is costly and expensive.

Sealing of cavitated occlusal carious lesions in the dentine of deciduous molars: a two-year randomised controlled clinical trial.

OBJECTIVES: This two-arm, parallel-group, tooth-randomised, controlled noninferiority clinical trial aimed to compare survival rates between the sealing and restoring of cavitated occlusal carious lesions in dentine [International Caries Detection and Assessment System (ICDAS) 5] of deciduous molars using resin-modified glass-ionomer cement (RMGIC) and to assess caries progression radiographically. MATERIALS AND METHODS: A total of 68 molars with ICDAS 5 occlusal lesions were randomly allocated into two groups, a sealing group (n = 31), in which RMGIC was placed directly over the carious lesion, and a restoration group (n = 37), in which a restoration with the same material was placed after selective caries removal. During the baseline and follow-up visits, dental caries was registered and caries activity was assessed according to a visuotactile criterion. At baseline, patient caries status (dmf-t) and cavity depth and extent (mesiodistal and buccolingual) were measured before RMGIC placement. An independent and blinded examiner evaluated the treated teeth using the USPHS criteria after one and two years. Standardised interproximal radiographs were taken for caries progression assessments. RESULTS: During the follow-up period, no lesion progression was observed radiographically. After one year (n = 60; 27 sealed and 33 restored) and two years (n = 48; 23 sealed and 25 restored) of follow-up, the treatment success rates were 78.8% and 76.0% in the restoration group and 59.3% and 47.8% in the sealing group, respectively. Multivariate Cox regression showed that lesions smaller than 2 mm in the mesiodistal extent were less prone to fail after one year (p = 0.03). However, survival curves (log-rank test) were statistically significantly different only after two years (p < 0.001). CONCLUSIONS: Sealing ICDAS 5 occlusal lesions of deciduous molars using RMGIC achieved lower survival rates than restorations. Both sealing and restoration effectively arrested caries progression for two years. Clinical relevance Sealing dentine carious lesions can be effective for treating lesions involving the inner and outer half of the dentine. Ultraconservative treatments can arrest carious lesions presenting obvious cavitation in primary molars. TRIAL REGISTRATION: ReBEC Register no. RBR-225n35.

Non-invasive and micro-invasive treatments to arrest active occlusal carious lesions in erupting permanent molars: A randomized clinical trial.

This study aimed to evaluate the efficacy of non-invasive and micro-invasive treatments on the arrest of occlusal enamel carious lesions in erupting permanent molars. This two-arm randomized clinical trial included 27 subjects, aged 5-11 years, with 64 erupting permanent molars presenting active occlusal enamel carious lesions (as assessed by the International Caries Detection and Assessment System [ICDAS]; scores 1-3). The sample was randomly assigned into two treatment groups: 1) resin-modified glass ionomer cement sealant (Clinpro XT Varnish; 3M ESPE) and 2) 4-week topical fluoride varnish application (Duraphat; Colgate). All children and parents received oral hygiene and dietary instructions. Teeth were evaluated at baseline and 3, 6, 9, and 12 months regarding the eruption stage, biofilm accumulation, as well as severity and activity of the carious lesions. The Kaplan-Meier method was used to evaluate the survival estimates for inactivation of the carious lesions for both treatment groups. Multivariate Cox regression models with shared frailty were performed to identify factors associated with the outcome (p < 0.05). After 12 months, 22% and 3% of the lesions treated with topical fluoride varnish and sealant, respectively remained active. The adjusted model demonstrated that younger children had a higher probability of active enamel carious lesions arresting (hazard ratio [HR] 0.42, 95% confidence interval [CI] 0.22-0.78; p=0.01). However, the probability of active enamel carious lesions arresting after sealant application was 8.85 times higher compared with fluoride varnish applications (p=0.01). Sealing is a more effective approach than fluoride varnish for arresting occlusal enamel carious lesions in erupting permanent molars.

Demystifying artificial intelligence and deep learning in dentistry.

Artificial intelligence (AI) is a general term used to describe the development of computer systems which can perform tasks that normally require human cognition. Machine learning (ML) is one subfield of AI, where computers learn rules from data, capturing its intrinsic statistical patterns and structures. Neural networks (NNs) have been increasingly employed for ML complex data. The application of multilayered NN is referred to as "deep learning", which has been recently investigated in dentistry. Convolutional neural networks (CNNs) are mainly used for processing large and complex imagery data, as they are able to extract image features like edges, corners, shapes, and macroscopic patterns using layers of filters. CNN algorithms allow to perform tasks like image classification, object detection and segmentation. The literature involving AI in dentistry has increased rapidly, so a methodological guidance for designing, conducting and reporting studies must be rigorously followed, including the improvement of datasets. The limited interaction between the dental field and the technical disciplines, however, remains a hurdle for applicable dental AI. Similarly, dental users must understand why and how AI applications work and decide to appraise their decisions critically. Generalizable and robust AI applications will eventually prove helpful for clinicians and patients alike.

Efficacy of 1.23% acidulated phosphate fluoride gel on non-cavitated enamel lesions: a randomized clinical trial.

A randomized controlled parallel clinical trial was conducted to evaluate the efficacy of the association of 1.23% topical professional acidulated phosphate fluoride (APF) gel with oral hygiene and dietary instructions on the arrest of active non-cavitated lesions in permanent, mixed, and temporary dentition in children between 3 and 12 years of age. Ninety-eight caries-active children were randomly divided into two groups: a fluoride gel group (n = 49) and a non-fluoridated gel group (n = 49). Each group received up to eight weekly applications of gel, weekly professional toothbrushing with oral hygiene instructions and dietary counselling. Caries lesions were assessed qualitatively through visual-tactile criteria performed in three stages: initial, intermediate, and final. Regression models were applied to identify risk indicators for caries control. Between-group comparison regarding the time taken to arrest the lesions was performed using Chi-squared and Fisher's exact tests. Seventeen children did not receive the allocated intervention, and one was lost to follow-up (n = 80). There was no difference between the control and placebo groups regarding the time to the arrest of the lesion (p >.05). The treatments showed similar results without significant statistical difference (p = 0.33; 95%CI: 0.32-1.48). No adverse effects were observed. It can be concluded that no additional effect of the association of 1.23% APF gel with oral hygiene using fluoride dentifrice and dietary instructions on the arrest of active non-cavitated lesions could be established. We can also confirm the importance of toothbrushing frequency and, consequently, the visible plaque reduction in the control of caries activity. RBR-37V5S3.

Narratives about a stigma: attributing meaning to the early loss of deciduous teeth on children's caregivers.

Qualitative approach about the implications that occur succeeding the premature loss teeth is still insufficient. This study aimed to understand the experience of early loss of deciduous teeth in children's lives, from the perspective of their caregivers. Qualitative case study included 52 caregivers of children from an outpatient service of a public university in the south of Brazil. Early loss of deciduous teeth to trauma or caries was identified through analysis of health records, and afterwards, semi-structured interviews were performed. Textual material was interpreted through the content analysis proposed by Bardin, supported by the ATLAS.ti software. The theoretical perspective of stigma was guided according to the principles of the phenomenology of Maurice Merleau-Ponty, centred on the experience of early loss of deciduous teeth as a historic-cultural expression of a social group. According to caregivers, premature loss of deciduous teeth due to trauma or decay brings functional limitations with chewing and speaking, and impairments related to social interaction with other children. The repercussions of missing teeth were not limited to the child's image, but also brought changes in families' daily lives. However, when early tooth loss was due to extraction because of pain and suffering, caregivers perceived the loss as 'commonplace' in children's lives. The understanding of how children see themselves without teeth in their social world for their caregivers, which also includes their family and friends, determines how much experiencing tooth loss affects their lives. Besides, caregivers' perceptions related to early loss of deciduous teeth should be included in strategies of oral health promotion programs.

Proteomic profile of the acquired enamel pellicle of professional wine tasters with erosive tooth wear.

The aim of this study was to compare the acquired enamel pellicle protein profile of professional wine tasters with mild and moderate erosive tooth wear. Twelve professional wine tasters participated (3 from a low tooth wear group; 9 from a high tooth wear group). Acquired enamel pellicle samples were collected and processed for proteomic analysis (nLC-ESI-MS/MS). The acquired enamel pellicle proteomic profile was different between the groups. The proteins found exclusively in the low tooth wear group were histatins 1 and 3 and mucins 7 and 21. When comparing the wear groups, proteins with higher levels in the low tooth wear group included neutrophil defensins (1 and 3), lysozyme C, lysozyme, myeloperoxidase, and squalene monooxygenase. In conclusion, the findings indicate that the proteins found at higher levels in the low tooth wear group and proteins exclusively found in the low tooth wear group might be protective and, therefore, could be good candidates for further studies regarding their potential to be added to dental products to protect professional wine tasters from extrinsic erosive tooth wear.

Influence of Isolation Technique on the Survival of Resin-Modified Glass-Ionomer Restorations in Primary Molars: A 9-Months Randomized Controlled Trial

ABSTRACT Objective: To compare the survival of occlusal and occlusal-proximal restorations performed with resin-modified glass-ionomer cement (RMGIC) in deciduous molars using rubber dam and cotton rolls isolation. Material and Methods: Ninety-two patients were included and 200 deciduous molars with cavitated occlusal or occlusoproximal dentin caries lesions were randomized into two groups: cotton rolls (n = 100) and rubber dam (n = 100) and RMGIC restorations were placed. At baseline and in the follow-up visit, presence, severity and activity of caries lesions were registered. Two independent, blinded examiners evaluated the treated teeth clinically using the USPHS criteria and radiographically after 9 months. Descriptive analysis, survival curve (log-rank test) and Cox regression were performed to assess risk factors related to failure. Results: Out of the 179 teeth (92 cotton rolls group and 87 rubber dam group) evaluated at 9-month follow-up period. No lesion progression was observed radiographically. The overall treatment success rate was 85.47% (83.47% for cotton rolls and 87.35 rubber dam group). No significant difference between isolation methods was observed in the log-rank test (p = 0.16). Cox regression showed no risk factors related to failure. Conclusion: No difference was found in the survival of occlusal and occlusal-proximal restorations performed with RMGIC in deciduous molars using a rubber dam and cotton rolls isolation after a 9-month follow-up period.

Demystifying artificial intelligence and deep learning in dentistry

Abstract Artificial intelligence (AI) is a general term used to describe the development of computer systems which can perform tasks that normally require human cognition. Machine learning (ML) is one subfield of AI, where computers learn rules from data, capturing its intrinsic statistical patterns and structures. Neural networks (NNs) have been increasingly employed for ML complex data. The application of multilayered NN is referred to as "deep learning", which has been recently investigated in dentistry. Convolutional neural networks (CNNs) are mainly used for processing large and complex imagery data, as they are able to extract image features like edges, corners, shapes, and macroscopic patterns using layers of filters. CNN algorithms allow to perform tasks like image classification, object detection and segmentation. The literature involving AI in dentistry has increased rapidly, so a methodological guidance for designing, conducting and reporting studies must be rigorously followed, including the improvement of datasets. The limited interaction between the dental field and the technical disciplines, however, remains a hurdle for applicable dental AI. Similarly, dental users must understand why and how AI applications work and decide to appraise their decisions critically. Generalizable and robust AI applications will eventually prove helpful for clinicians and patients alike.

Non-invasive and micro-invasive treatments to arrest active occlusal carious lesions in erupting permanent molars: A randomized clinical trial

Abstract: This study aimed to evaluate the efficacy of non-invasive and micro-invasive treatments on the arrest of occlusal enamel carious lesions in erupting permanent molars. This two-arm randomized clinical trial included 27 subjects, aged 5-11 years, with 64 erupting permanent molars presenting active occlusal enamel carious lesions (as assessed by the International Caries Detection and Assessment System [ICDAS]; scores 1-3). The sample was randomly assigned into two treatment groups: 1) resin-modified glass ionomer cement sealant (Clinpro XT Varnish; 3M ESPE) and 2) 4-week topical fluoride varnish application (Duraphat; Colgate). All children and parents received oral hygiene and dietary instructions. Teeth were evaluated at baseline and 3, 6, 9, and 12 months regarding the eruption stage, biofilm accumulation, as well as severity and activity of the carious lesions. The Kaplan-Meier method was used to evaluate the survival estimates for inactivation of the carious lesions for both treatment groups. Multivariate Cox regression models with shared frailty were performed to identify factors associated with the outcome (p < 0.05). After 12 months, 22% and 3% of the lesions treated with topical fluoride varnish and sealant, respectively remained active. The adjusted model demonstrated that younger children had a higher probability of active enamel carious lesions arresting (hazard ratio [HR] 0.42, 95% confidence interval [CI] 0.22-0.78; p=0.01). However, the probability of active enamel carious lesions arresting after sealant application was 8.85 times higher compared with fluoride varnish applications (p=0.01). Sealing is a more effective approach than fluoride varnish for arresting occlusal enamel carious lesions in erupting permanent molars.

Enamel Subsurface Caries-Like Lesions Induced in Human Teeth By Different Solutions: A TMR Analysis.

This study assessed the effectiveness of models for developing subsurface caries lesions in vitro and verified mineral changes by transverse microradiography (TMR). Enamel blocks from permanent (n=5) and deciduous teeth (n=5) were submitted to lesion induction by immersion in demineralizing solutions during 96 h, followed by pH cycles of demineralization (de) and remineralization (re) for 10 days. Two de-/re solutions were tested. Demineralizing solution "A" was composed by 2.2 mM CaCl2, 2.2 mM KH2PO4, 0.05 M acetic acid, with pH 4.4 adjusted by 1 M KOH. Demineralizing solution "B" was composed by 2.2 mM CaCl2, 2.2 mM NaH2PO4, 0.05 M acetic acid and 0.25 ppmF, with pH 4.5 adjusted by 1M KOH. Solution "A" produced cavitated lesions in permanent teeth, whereas solution "B" led to subsurface lesions in deciduous teeth. Solution "B" was then tested in enamel blocks from permanent teeth (n=5) and subsurface lesions were obtained, so that solution "B" was employed for both substrates, and the blocks were treated with slurries of a fluoride dentifrice (1450 ppm F, as NaF, n=5) or a fluoride-free dentifrice (n=5). Solution "B" produced subsurface lesions in permanent and primary teeth of an average (±SD) depth of 88.4µm (±14.3) and 89.3µm (±15.8), respectively. TMR analysis demonstrated that lesions treated with fluoride-free dentifrice had significantly greater mineral loss. This study concluded that solution "B" developed subsurface lesions after pH cycling, and that mineral changes were successfully assessed by TMR.

Two-Year Split-Mouth Randomized Controlled Clinical Trial on the Progression of Proximal Carious Lesions on Primary Molars After Resin Infiltration.

Purpose: The purpose of this split-mouth, randomized, controlled clinical trial was to assess the progression of early proximal carious lesions on primary molars after resin infiltration. Methods: Twenty-eight children presenting two primary molars with proximal carious lesions detected radiographically (on the outer half of the enamel up to the outer one-third of dentin) were included. Baseline assessments consisted of standard digital bitewing radiographs, Visual Plaque Index (VPI), Gingival Bleeding Index (GBI), and visual examination of caries. Proximal lesions were randomly allocated into two groups: (1) resin infiltration (test) and (2) no infiltration (control). Reassessments were performed after two years. Lesion progression was considered when the radiographic score increased. Results: A significant difference in lesion progression was observed between test (54.1 percent) and control (79.2 percent) groups after two years (McNemar's test, P=0.03). Logistic regression for matched pairs showed that the test group had an 82 percent lower risk of caries progression (odds ratio equals 0.18, 95%CI 0.29 to 0.31). Conclusions: Infiltrating proximal lesions decreases radiographic caries progression in primary molars after a two-year follow-up period.