High-Resolution Characterization of Enamel Remineralization Using Time-of-Flight Secondary Ion Mass Spectrometry and Electron Microscopy.

INTRODUCTION: The aim of this in vitro study was to assess the suitability of high-resolution time-of-flight secondary ion mass spectrometry (ToF-SIMS) for visualizing cross-sectional changes in human enamel microstructure and chemical composition during treatment and remineralization cycling of artificially generated caries lesions underneath an artificial plaque. METHODS: Treatments consisted of exposure to twice daily toothpaste/water slurries prepared from 0, 1,100, and 5,000 µg/g fluoride (F) NaF/silica toothpastes. In addition, treatments with slurries prepared from 1,100 µg/g F SnF2/silica toothpastes were done using 44Ca in the remineralization solution to allow for differentiation of newly formed mineral and exploration of incorporated metal dopants using ToF-SIMS. Complementary microhardness, scanning electron microscopy, and high-resolution transmission electron microscopy (HR-TEM) investigations were performed on enamel cross sections. RESULTS: HR-TEM was used for the first time to determine the change in crystallinity during remineralization revealing distinct microstructural zones within one lesion. Chemical mapping using ToF-SIMS demonstrated that the distribution of F, while observed primarily in the new mineral phase, was widespread throughout the lesion with 44Ca substantially limited to the remineralizing mineral. Both penetrated the inter-rod spaces of the sound enamel illustrating how acid damage propagates into the native mineral as the caries lesion deepens. HR-TEM examination revealed different regions within the lesion characterized by distinct micro- and ultrastructures. Importantly, HR-TEM revealed a return of crystallinity following remineralization. F dose-response observations verified the ability of these high-resolution techniques to differentiate remineralization efficacy. CONCLUSION: The collective results provided new insights such as the visualization of F or calcium penetration pathways, as well as new tools to study the caries process.

Diagnóstico e decisões de tratamento para cárie induzido por luz: aplicação de uma câmera intraoral com fluorescência / Diagnosis and treatment decisions for light-induced caries: application of an intraoral fluorescence camera

Objetivou-se verificar se 1) o diagnóstico por fluorescência (DF) e o exame visual (EV), são igualmente eficazes em detectar lesões de mancha branca (MB); 2) verificar se imagens obtidas por uma câmera intraoral, no modo luz branca (LB) ou fluorescente (LF) são comparáveis à radiografia digital (RD) no diagnóstico e no auxílio às decisões de tratamento para cárie oclusal e 3) verificar se a câmera intraoral, no modo LF, comporta-se com precisão, ao definir se a remoção químico-mecânica (RQM) de dentina cariada com gel de papaína estabelece um adequado limite para o preparo. Neste contexto, três estudos foram propostos. O primeiro estudo contou com uma revisão sistemática da literatura, a fim de verificar se o DF e o EV, são comparáveis em detectar lesões de MB relacionada a ortodontia fixa. Cinco estudos foram incluídos nesta revisão. O diagnóstico de MB relacionada a ortodontia fixa, realizado por fluorescência, foi satisfatório em relação ao EV, porém com baixa qualidade das evidências. O segundo estudo contou com uma pesquisa ex vivo, com 10 molares permanentes e 26 dentistas avaliadores, e propôs verificar se imagens obtidas pela câmera intraoral SoproLife®, no modo LB e LF, e as RD, são comparáveis no diagnóstico e decisões de tratamento de cárie oclusal, comparado a um padrão-ouro em microtomografia computadorizada (micro-CT). Para o diagnóstico de cárie, não foi encontrada diferença entre os três métodos (p=0,415), com uma concordância geral baixa (média de 15,3%), enquanto para as decisões de tratamento, o percentual de acertos entre os três métodos foi maior para a LB (48,1%) e LF (51,2%) em relação a RD (30,4%) (p<0,001). O terceiro estudo foi realizado ex vivo, a fim de verificar se a câmera intraoral SoproLife®, no modo LF, comporta-se com precisão, ao definir se a RQM de dentina cariada pelo gel é suficiente comparado a um padrão-ouro em micro-CT. A efetividade de dois géis de papaína na remoção de cárie em dentina também foi estudada. Após o escaneamento inicial, 20 molares permanentes foram pareados e divididos em grupos, (G1) Papacárie Duo® e (G2) Brix3000®. O limiar para a detecção de tecido cariado de <1,11 g/cm3, foi utilizado. A eficácia da RQM foi menor para o Papacárie Duo® comparado ao Brix3000® (p<0,05). Ambos os grupos apresentaram falsos positivos quando a câmera intraoral SoproLife® considerou tecido cariado presente. Deste modo, conclui-se que: 1) O diagnóstico de MB relacionada a ortodontia fixa por DF, mostrou-se satisfatório em relação ao EV; 2) Imagens em LB, LF e RD, foram eficazes nas decisões de tratamento de cárie oclusal; 3) a câmera intraoral SoproLife® não definiu apropriadamente se a RQM pelo gel foi suficiente; 4) a utilização dos géis de papaína resultou em remoção de tecido cariado conservativa, preservando tecido dental sadio. (AU)

The aim was to verify if 1) fluorescence diagnosis (FD) and visual examination (VE) are equally effective in detecting white spot (WS) lesions; 2) to verify whether images transmitted by an intraoral camera in white light (WL) mode or fluorescent (FL) are comparable to digital radiography (DR) in diagnosing and aiding treatment decisions for occlusal caries and 3) verify whether the intraoral camera, in FL mode, behaves accurately, when defining whether chemical-mechanical removal (CMR) of carious dentin with papain gel results in appropriate threshold for cavity preparation. In this context, three studies were proposed. The first study was a systematic review of the literature, in order to verify if FD and VE are comparable in detecting WS lesions related to fixed orthodontics. Five studies were included in this review. The diagnosis of WS, performed by fluorescence, was satisfactory in relation to VE, but with very low quality of evidence. The second study included an ex vivo survey, with 10 permanent molars and 26 examiners, and verified whether images obtained by the SoproLife® intraoral camera, in WL and FL mode, and the DR, are comparable in the diagnosis and treatment decisions of occlusal caries compared to a gold standard in micro-computed tomography (micro-CT). For caries diagnosis, no difference was found between the three methods (p=0.415), with a low overall agreement (mean of 15.3%), while for treatment decisions, the percentage of correct answers between the three methods was higher for WL (48.1%) and FL (51.2%) compared to DR (30.4%) (p<0.001). The third study was performed ex vivo, in order to verify whether SoproLife® intraoral camera, in FL mode, behaves accurately, when defining whether the CMR of carious dentin is sufficient compared to a gold standard in micro-CT. The effectiveness of two papain gels in removing caries in dentin was also studied. After the initial scan, 20 permanent molars were paired and divided into groups, (G1) Papacárie Duo® and (G2) Brix3000®. A threshold for carious tissue (<1.11 g/cm3) was used. The effectiveness of CMR was lower for Papacárie Duo® compared to Brix3000® (p<0.05). Both groups showed false positives when SoproLife® intraoral camera evaluated carious tissue present. Thus, it is concluded that: 1) The diagnosis of WS related to fixed orthodontics due to FD, was satisfactory in relation to VE; 2) WL, FL and DR images were effective in defining occlusal caries treatment decisions and 3) SoproLife® intraoral camera did not properly define whether CMR sufficient and 4) the use of papain gels resulted in conservative removal of carious tissue, preserving sound dental tissue. (AU)

Detecting white spot lesions on dental photography using deep learning: A pilot study.

OBJECTIVES: We aimed to apply deep learning to detect white spot lesions in dental photographs. METHODS: Using 434 photographic images of 51 patients, a dataset of 2781 cropped tooth segments was generated. Pixelwise annotations of sound enamel as well as fluorotic, carious or other types of hypomineralized lesions were generated by experts and assessed by an independent second reviewer. The union of the reviewed annotations were used to segment the hard tissues (region-of-interest, ROI) of each image. SqueezeNet was employed for modelling. We trained models to detect (1) any white spot lesions, (2) fluorotic lesions and (3) other-than-fluorotic lesions. Modeling was performed on both the cropped and the ROI images and using ten-times repeated five-fold cross-validation. Feature visualization was applied to visualize salient areas. RESULTS: Lesion prevalence was 37 %; the majority of lesions (24 %) were fluorotic. None of the metrics differed significantly between the models trained on cropped and ROI imagery (p > 0.05/t-test). Mean accuracies ranged between 0.81-0.84, without significant differences between models trained to detect any, fluorotic or other-than-fluorotic lesions (p > 0.05). Specificities were 0.85-0.86; sensitivities were lower (0.58-0.66). Models to detect any lesions showed positive/negative predictive values (PPV/NPV) between 0.77-0.80, those to detect fluorotic lesions 0.67 (PPV) to 0.86 (NPV), and those to detect other-than-fluorotic lesions 0.46 (PPV) to 0.93 (NPV). Light reflections were the main reason for false positive detections. CONCLUSIONS: Deep learning showed satisfying accuracy to detect white spot lesions, particularly fluorosis. Some models showed limited stability given the small sample available. CLINICAL SIGNIFICANCE: Deep learning is suitable for automated classification of retro- or prospectively collected imagery and may assist practitioners in discriminating white spot lesions. Future studies should expand the scope into more granular multi-class detections on a larger and more generalizable dataset.

Allium sativum extract as an irrigant in pulpectomy of primary molars: A 12-month short-term evaluation.

This study indented to assess the clinical and radiographic assessment of Allium sativum extract as an intracanal irrigant for pulpectomy of primary molars. Ninety children with 110 teeth submitted were categorized into two groups. Clinical and radiographic success rates were checked at 3, 6, and 12 months. Qui-square test at a level of significance was ˂0.05. There was no statistically significant difference (p Ë‚ .05) between the two groups that has not been detected clinically or radiographically. Clinical and radiographic success rates of garlic extract at 3 months were (80% and 72.7%), which declined at 6 and 12 months to be 76.4% 6 and 74.5% respectively. For NaOCl group, clinical and radiographic success rates were 87.3% and 85.5% at 3 months, 87.3% and 87.3% at 6 months and 89.1% and 87.3% at 12 months. A. sativum extract can be used efficiently as an irrigant for pulpectomy of primary molar root canals.

Iodoform Vs Calcium Hydroxide/Zinc Oxide based pastes: 12-month findings of a Randomized Controlled Trial.

This study evaluated clinical and radiographic twelve-month outcomes of root canal treatments (CT) with smear layer removal, performed in primary teeth, using two different root canal filling materials. Pulpectomy was performed on 27 primary teeth with necrosis or irreversible pulpitis, caused by dental caries or trauma, in 23 children (2-7 years old). A single trained operator performed the CT in a single visit in cases without periapical or interradicular radiolucency (PIR) or in multiple visits in cases with PIR. Participants were selected based on specific inclusion and exclusion criteria, and randomly allocated into two groups: Group 1 (G1) - iodoform paste (iodoform + camphorated parachlorophenol + ointment comprising prednisolone acetate 5.0 mg and rifamycin 1.5 mg); Group 2 (G2) - Calen®/ZO paste. Treated teeth were restored with composite resin immediately after the root canal filling. The outcomes were evaluated clinically and radiographically according to specific criteria. Two blinded and standardized evaluators assessed the radiographic outcomes. We used descriptive analyses due to the small sample size. CTs were performed due to caries lesions in 70.4% of the cases and due to trauma in 29.6%. Only one tooth of G1 was unsuccessful; hence, pulpectomy performance in both groups was not influenced by the filling material, nor by any other analyzed variable. The level of the root canal filling was better in the Calen®/ZO group. The clinical and radiographic twelve-month outcomes indicated successful treatment, independently of the root filling material used.

Iodoform Vs Calcium Hydroxide/Zinc Oxide based pastes: 12-month findings of a Randomized Controlled Trial

Abstract This study evaluated clinical and radiographic twelve-month outcomes of root canal treatments (CT) with smear layer removal, performed in primary teeth, using two different root canal filling materials. Pulpectomy was performed on 27 primary teeth with necrosis or irreversible pulpitis, caused by dental caries or trauma, in 23 children (2-7 years old). A single trained operator performed the CT in a single visit in cases without periapical or interradicular radiolucency (PIR) or in multiple visits in cases with PIR. Participants were selected based on specific inclusion and exclusion criteria, and randomly allocated into two groups: Group 1 (G1) - iodoform paste (iodoform + camphorated parachlorophenol + ointment comprising prednisolone acetate 5.0 mg and rifamycin 1.5 mg); Group 2 (G2) - Calen®/ZO paste. Treated teeth were restored with composite resin immediately after the root canal filling. The outcomes were evaluated clinically and radiographically according to specific criteria. Two blinded and standardized evaluators assessed the radiographic outcomes. We used descriptive analyses due to the small sample size. CTs were performed due to caries lesions in 70.4% of the cases and due to trauma in 29.6%. Only one tooth of G1 was unsuccessful; hence, pulpectomy performance in both groups was not influenced by the filling material, nor by any other analyzed variable. The level of the root canal filling was better in the Calen®/ZO group. The clinical and radiographic twelve-month outcomes indicated successful treatment, independently of the root filling material used.

Histochemical changes of occlusal surface enamel of permanent teeth, where dental caries is questionable vs sound enamel surfaces.

AIM: This in vitro study was to classify questionable for caries occlusal surfaces (QCOS) of permanent teeth according to ICDAS codes 1, 2, and 3 and to compare them in terms of enamel mineral composition with the areas of sound tissue of the same tooth. METHODS: Partially impacted human molars (60) extracted for therapeutic reasons with QCOS were used in the study, photographed via a polarised light microscope and classified according to the ICDAS II (into codes 1, 2, or 3). The crowns were embedded in clear self-cured acrylic resin and longitudinally sectioned at the levels of the characterised lesions and studied by SEM/EDX, to assess enamel mineral composition of the QCOS. Univariate and multivariate random effect regressions were used for Ca (wt%), P (wt%), and Ca/P (wt%). RESULTS: The EDX analysis indicated changes in the Ca and P contents that were more prominent in ICDAS-II code 3 lesions compared to codes 1 and 2 lesions. In these lesions, Ca (wt%) and P (wt%) concentrations were significantly decreased (p = 0.01) in comparison with sound areas. Ca and P (wt%) contents were significantly lower (p = 0.02 and p = 0.01 respectively) for code 3 areas in comparison with codes 1 and 2 areas. Significantly higher (p = 0.01) Ca (wt%) and P (wt%) contents were found on sound areas compared to the lesion areas. CONCLUSIONS: The enamel of occlusal surfaces of permanent teeth with ICDAS 1, 2, and 3 lesions was found to have different Ca/P compositions, necessitating further investigation on whether these altered surfaces might behave differently on etching preparation before fissure sealant placement, compared to sound surfaces.

Comparison of Knoop and Vickers surface microhardness and transverse microradiography for the study of early caries lesion formation in human and bovine enamel.

OBJECTIVE: The aims of the present laboratory study were twofold: a) to investigate the suitability of Knoop and Vickers surface microhardness (SMH) in comparison to transverse microradiography (TMR) to investigate early enamel caries lesion formation; b) to compare the kinetics of caries lesion initiation and progression between human and bovine enamel. DESIGN: Specimens (90×bovine and 90×human enamel) were divided into six groups (demineralization times of 8/16/24/32/40/48h) of 15 per enamel type and demineralized using a partially saturated lactic acid solution. SMH was measured before and after demineralization and changes in indentation length (ΔIL) calculated. Lesions were characterized using TMR. Data were analyzed (two-way ANOVA) and Pearson correlation coefficients calculated. RESULTS: ΔIL increased with increasing demineralization times but plateaued after 40h, whereas lesion depth (L) and integrated mineral loss (ΔZ) increased almost linearly throughout. No differences between Knoop and Vickers SMH in their ability to measure enamel demineralization were observed as both correlated strongly. Overall, ΔIL correlated strongly with ΔZ and L but only moderately with the degree of surface zone mineralization, whereas ΔZ and L correlated strongly. Bovine demineralized faster than human enamel (all techniques). CONCLUSIONS: Lesions in bovine formed faster than in human enamel, although the resulting lesions were almost indistinguishable in their mineral distribution characteristics. Early caries lesion demineralization can be sufficiently studied by SMH, but its limitations on the assessment of the mineral status of more demineralized lesions must be considered. Ideally, complementary techniques to assess changes in both physical and chemical lesion characteristics would be employed.

Comparative study of a wireless digital system and 2 PSP digital systems on proximal caries detection and pixel values.

This study compared the radiographic image quality of 2 photostimulable phosphor (PSP) plate systems with a radiographic system against a complementary metal oxide silicon (CMOS) system. Using the 3 digital systems, 160 approximal surfaces were radiographed under standardized conditions. Using a 5-point scale, 6 observers scored the resulting images for the presence of caries. The presence of caries was validated histologically, and the image receptors were evaluated using receiver operating characteristic curve analysis. The digital systems were used to take radiographs of an aluminum step wedge for objective analysis with pixel density measurements. The mean pixel values were analyzed statistically using the Kruskal-Wallis test and Dunn multiple comparison test (P < 0.01). The performance of the new CMOS system was comparable to the PSP plate systems and radiographic film.

Oral pathologies of the Neolithic Iceman, c.3,300 BC.

The famous Iceman 'Ötzi' (South Tyrol Museum of Archaeology, Bolzano, Italy), a Neolithic human ice mummy, offers a unique opportunity to study evolutionary aspects of oral disease. The aim of this study was to assess, for the very first time, his oral cavity, which surprisingly had never been examined systematically. Based on several computed tomography (CT) scans from 1991 onwards and on macroscopic investigation, only a few findings, such as a central maxillary diastema, heavy abrasions, and missing wisdom teeth, were known. We re-evaluated the latest CT scans from 2005 and found various oral pathologies. In line with the increase of tooth decay in the Neolithic - because of diet change in this historic transition phase - several carious lesions were found, one of which penetrated into the dental pulp. In accordance with the Iceman's troubled life, as several injuries on his body and his violent death attest, mechanical trauma of one of his upper front teeth is evident. Finally, the poor periodontal condition of the Iceman's dentition (e.g. loss of alveolar bone), indicative of periodontitis, was assessed. These oral pathological findings in the Iceman's dentition provide a unique glimpse into the evolutionary history of oral conditions.

Assessment of enamel-dentin caries lesions detection using bitewing PSP digital images.

OBJECTIVES: The aim of this study was to evaluate the detection of enamel-dentin occlusal caries using photostimulable phosphor plates. MATERIAL AND METHODS: The ability to detect enamel-dentin occlusal caries in 607 premolars and molars from 47 patients between 10 and 18 years old, referred to the School of Dentistry of the Federal University of Bahia, Brazil, was evaluated based on clinical and radiographic examinations, using the criteria proposed in a previous study. A total of 156 bitewing digital images were obtained using Digora® (Soredex Medical Systems, Helsinki, Finland) phosphor plates. The plates were scanned and the images were captured and displayed on a computer screen. Image evaluation was done using Digora® for Windows 2.1 software, Soredex®. The radiologists were allowed to use enhancement tools to obtain better visibility during scoring of the teeth based on the radiographic criteria proposed in a previous study. Descriptive analysis and chi-squared proportion tests were done at 5% significance level. RESULTS: The results of clinical examination showed a higher prevalence of teeth with a straight dark line or demineralization of the occlusal fissure (score 1) and a lower prevalence of sealed teeth (score 5). In the bitewing digital images, 47 teeth presented visible radiolucency, circumscribed, in dentin under occlusal enamel (enamel-dentin caries lesions). CONCLUSIONS: Correlating the clinical and radiographic findings, it was found that in the majority of teeth diagnosed by radiographic images as having enamel-dentin caries, no caries could be detected by clinical examination.

Laser-induced fluorescence and X-ray spectral analysis of carious process in hard dental tissues.

Morphological and spectral X-ray analysis of carious and noncarious extracted teeth showed the patterns of dentin ossification in caries of different degree. Parietal ectopic ossification of the canal and cavity lumens in stages III and IV dental caries is regarded as a specific structural marker of pathological regeneration. The X-ray spectral analysis showed that the progress of carious process is paralleled by loss of mineral components. Laser-induced fluorescent study of tissues in extracted teeth showed 4 spectral bands corresponding to mineral and protein components of the tooth. The progress of carious process was associated with reduction of the fluorescence intensities of the spectral bands characteristic of dental collagen and mineral components.

The correlation of DIFOTI to clinical and radiographic images in Class II carious lesions.

BACKGROUND: The authors conducted a study to evaluate the correlation between digital imaging fiber-optic transillumination (DIFOTI) (KaVo Dental, Lake Zurich, Ill.) and clinical and radiographic images in estimating the true clinical axial extension of Class II carious lesions. METHODS: The authors examined 51 Class II carious lesions visually, imaged them by means of DIFOTI and radiographed them with D-speed film and a complementary metal oxide silicon (CMOS)-based digital radiographic sensor. They validated axial extension of the lesions clinically. They compared the clinical and radiographic depths of the carious lesion with the size of the lesion on the DIFOTI images. RESULTS: The authors detected 84 percent of the lesions with DIFOTI, and 82 percent showed a visible dark shadow under the marginal ridge when examined clinically. DIFOTI correlated significantly with the clinical depth of decay (Pearson r = 0.43189). The combination of a CMOS digital sensor and DIFOTI (R2 = 0.7210) provided readings closer to the clinical measures than did the combination of D-speed film and DIFOTI (R2 = 0.6215). CONCLUSIONS: DIFOTI images correlated with clinical depth, especially in smaller lesions, and improved the estimation of lesion size when used in conjunction with the CMOS digital sensor and D-speed images. CLINICAL IMPLICATIONS: Using radiographs in combination with DIFOTI images could help clinicians determine the presence and, to some extent, the size of proximal caries, especially in smaller lesions.

Caries experience in preschool children referred for specialist dental care in hospital.

BACKGROUND: Increasing numbers of preschool children are being referred for specialist dental management in a paediatric hospital. Most cases have severe early childhood caries and require comprehensive management under general anaesthesia. The present study investigated risk factors for disease presence at initial consultation. METHODS: A convenience sample of 125 children under four years of age from the north Brisbane region were examined and caries experience recorded using dmft and dmfs indices. A self-administered questionnaire obtained information regarding social, demographic, birth, neonatal, infant feeding and dental health behaviour variables. The data were analysed using the chi-square and one-way analysis of variance procedures. RESULTS: Ninety-four per cent of referred children had severe ECC with mean dmft of 10.5 +/- 3.8 and mean dmfs of 27.1 +/- 15.1. Prevalence of severe ECC was significantly higher in children allowed a sweetened liquid in the infant feeding bottle (99 per cent) and allowed to sip from an infant feeding bottle during the day (100 per cent). Mean dmfs was significantly higher in children allowed to sleep with a bottle (28.7) and sip from a bottle during the day (29.9), children from a non-Caucasian background (31.8), those children that commenced regular toothbrushing between 6 to 12 months of age (28.1), had no current parental supervision of daily tooth-brushing (34.2) and had not taken daily fluoride supplements (27.8), vitamin supplements (27.8) or prescription medicine previously (27.6). CONCLUSIONS: The behavioural determinants for severe early childhood caries presence in hospital-referred children were similar to those identified in the regional preschool population.

Changes in caries experience among 6-year-olds in Blekinge, Sweden between 1994 and 2000.

For 6-year-old children in the County of Blekinge, the goal was that > 65 percent should have dmft = 0 in the year 2000. To formulate this goal a study on prevalence and distribution of caries in 6-year-old children was performed in 1994. The aim of the present study was to evaluate whether the dental health goal for the year 2000 was achieved and compare clinical data regarding oral status in children in 1994 and in 2000. The material comprised a random sample of 225 children. The studyfrom year 1994, which included 213 children, was repeated. A clinical investigation was performed and completed with bite-wing radiographs on individual indication, whenever the proximal surfaces could not be inspected clinically due to close and broad contact. In addition, the parents were asked questions about toothbrushing and use of fluoride tablets. 53 percent of the children showed healthy teeth with no initial caries lesions or restorations compared to 35 percent in 1994. The pattern of dental health was still very skewed among the children. The children with nine or more decayed surfaces increased from 2 percent in 1994 to almost 4 percent in 2000. The number of fissure sealings performed had increased between 1994 and 2000 by almost 50 percent in both primary molars and first permanent molars. However,the use of fluoride tablets had decreased from 20 percent in 1994 to 7 percent of the children in 2000. The data showed a decline in prevalence of dmf teeth and an increase in the percent of caries-free children but the difference was not significant on the 5% level. However, as 47% of the children were in need of restorative treatment, our dental health goal was not achieved. We also recommend that our preventive program with focus on primary prevention and individual risk assessment should also be targeted at the whole population of pre-school children and their parents.

Programa preventivo de caries dental en niños y adolescentes cubanos / Preventive program of dental caries in Cuban children and adolescents

Se abordan los antecedentes del programa llevado a cabo en nuestro país, basados en enjuagatorios con solución de fluoruro de sodio. Se hace referencia a la mala situación de salud bucal que existía en gran parte de la población antes de 1959, las primeras experiencias con la aplicación de este método en el año 1969 y lo que esto significó, como parte del Programa Nacional Preventivo de Caries Dental. Igualmente se señalan las normas y metodología orientadas por el nivel nacional, así como los resultados de las investigaciones cualitativas y cuantitativas, de las cuales se ha podido obtener información acerca de la efectividad de esta medida preventiva contra la caries dental a lo largo de estos años(AU)

The antecedents of the program implemented in our country based on mouthwashes with sodium fluoride solution are dealt with. Reference is made to the poor situation of oral health that existed among most of the population before 1959, to the first experiences with the application of this method in 1969, and to what it meant as part of the National Program for the Prevention of Dental Caries. Likewise, the norms and methodology established at the national level, as well as the results of the quantitative and qualitative researches, from which information about the effectiveness of this preventive measure against dental caries has been obtained along these years, are stressed(AU)

Digital radiography: an overview.

Since the discovery of X-rays in 1895, film has been the primary medium for capturing, displaying, and storing radiographic images. It is a technology that dental practitioners are the most familiar and comfortable with in terms of technique and interpretation. Digital radiography is the latest advancement in dental imaging and is slowly being adopted by the dental profession. Digital imaging incorporates computer technology in the capture, display, enhancement, and storage of direct radiographic images. Digital imaging offers some distinct advantages over film, but like any emerging technology, it presents new and different challenges for the practitioner to overcome. This article presents an overview of digital imaging including basic terminology and comparisons with film-based imaging. The principles of direct and indirect digital imaging modalities, intraoral and extraoral applications, image processing, and diagnostic efficacy will be discussed. In addition, the article will provide a list of questions dentists should consider prior to purchasing digital imaging systems for their practice.

[Effect of sodium chloride treatment on remineralization of human root dentine caries in vitro].

OBJECTIVE: To investigate the influence of soluble phosphoprotein removal from artificial dentin caries lesions by pretreatment of NaCl on subsequent remineralization. METHODS: Human root dentin samples were demineralized in an acidic gel (pH = 4.4) at 37 degrees C for 48 hours. Samples were pretreated with 0.5 mol/L NaCl solution and 0.5 mol/L disodium EDTA solution respectively. The histomorphologic changes of root caries surface were examined by scannings electronic microscope. Mineral profiles were assessed by means of microradiography. RESULTS: No histomorphologic changes were present on root caries surface after treated with 0.5 mol/L NaCl solution, while many opened dentin tubules were seen after treated with 0.5 mol/L disodium EDTA solution. The remineralization results showed that pretreatment with 0.5 mol/L NaCl solution increased more remineralization than pretreated with 0.5 mol/L disodium EDTA solution. CONCLUSION: 0.5 mol/L NaCl solution has no damage on the root caries surface. The in vitro results suggested that removal of soluble phosphoprotein from dentin lesions is an interesting approach to enhance remineralization.