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This work deals with microcontaminants (MCs) removal by natural solar zero-valent iron (ZVI) process at natural pH in actual matrices. Commercial ZVI microspheres were selected as ZVI source and hydrogen peroxide and persulfate were used as oxidant agents. The experimental plan comprised the evaluation of sulphates and carbonates/bicarbonates effect on process performance, the possibility of adding an iron chelate (EDDS) to take advantage of leached iron and the treatment of MCs in actual MWWTP secondary effluent. The presence of sulphates and EDDS addition did not lead to significant changes in the process efficiency, while the carbonates naturally present in natural water (458 mg/L) diminished the treatment time need to reach the decontamination goal. Finally, the treatment of a MCs mixture consisting of Atrazine, Carbendazim, Imidacloprid, and Thiamethoxam in the range of µg/L in actual MWWTP secondary effluent by solar/msZVI/H2O2 and solar/msZVI/S2O82- obtained 7 and 22% of total removal after 180 min, respectively, which indicated a moderate competitiveness of these processes with respect to other advanced oxidation processes.

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Solar zerovalent iron (ZVI) was studied at circumneutral pH in combination with hydrogen peroxide and persulfate for removal of imidacloprid as a model contaminant in natural water. Three commercial ZVI sources, steel wool (ZVI-SW) and two iron micro-powders (ZVI-MS and ZVI-S) were independently evaluated. First, different ZVI corrosion conditions were tested in contact with air, exposed to natural solar radiation and with addition of oxidants, such as H2O2 and S2O82-, demonstrating the importance of released iron. Then, the technical feasibilities of solar/H2O2/ZVI and solar/S2O82-/ZVI were assessed for the elimination of 1 mg/L of imidacloprid. In general, H2O2 concentrations and treatment times were high. Only ZVI-MS (1 mM) reached 80% imidacloprid degradation after 157 min and 3 mM (102 mg/L) of H2O2. Solar/S2O82-/ZVI performance was better, reaching >80% imidacloprid degradation in <60 min with 1 mM (192 mg/L) S2O82- for all ZVI sources. Efficiency was highest with ZVI-MS, which was therefore selected for feasibility testing of a microcontaminant (MC) mixture containing 100 µg/L each of atrazine, carbendazim, imidacloprid and thiamethoxam with both solar/oxidizing agents/ZVI. H2O2 took 180 min to achieve 76% degradation of the sum of MCs, while 80% total degradation was reached after 69 min by adding S2O82-, confirming its higher efficiency. Finally, this study showed that ZVI in combination with solar radiation does not enhance significantly the photocatalytic cycle.

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Simultaneous microorganism inactivation and organic microcontaminant removal in municipal wastewater treatment plant (WWTP) secondary effluents by the solar photo-Fenton process mediated by Fe3+-NTA is studied in depth. To achieve this objective, different key aspects were addressed: (i) the effect of initial Fe3+-NTA concentration at 1:1 molar ratio (0.10-0.30 mM) and H2O2 concentration (1.47-5.88 mM), (ii) the effect of initial microorganism load (103 and 106 CFU/mL) and (iii) the impact of the disinfection target on treatment cost. The first stage of this work was carried out in simulated WWTP effluent spiked with 100 µg/L of imidacloprid (IMD) as model microcontaminant and inoculated with Escherichia coli (E. coli) K-12 as reference strain, in a pilot scale raceway pond reactor with 5-cm of liquid-depth. Secondly, the most cost-effective conditions were validated in actual WWTP effluent. The kinetic analysis revealed that increasing Fe3+-NTA concentration over 0.20 mM does not significantly reduce treatment time due to the limited effect caused on the volumetric rate photon absorption. Treatment cost is determined by the disinfection process, since IMD removal was always faster than E. coli inactivation. The most cost-effective strategy to achieve 10 CFU/100 mL of E. coli (Regulation EU 2020/741) was 0.20/4.41 mM Fe3+-NTA/H2O2, with a cost of 0.32 €/m3. A less restrictive disinfection target, 100 CFU/100 mL, allowed reducing reactant concentration and cost, 0.10/1.47 mM Fe3+-NTA/H2O2 and 0.15 €/m3, respectively. In both cases, no regrowth at 24 h and more than 90% of IMD removal were observed.

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This work critically reviews the present knowledge about the use of Raceway Pond Reactors (RPR) to treat municipal wastewater treatment plant (MWWTP) secondary effluents by solar photo-Fenton process. The possibility of using RPR to treat industrial wastewater, which has been barely explored, is also reviewed. Initially, the general concepts and operation principles of RPR are described as well as their origin for photo-Fenton applications. Then, the main results and advances related to contaminants of emerging concern (CECs) removal, inactivation of microorganisms, industrial wastewater treatment and kinetic modelling are presented. Key aspects such as the impact of liquid depth, the continuous flow operation feasibility, the increase in treatment capacity, and the kinetic modelling are addressed along the review. At the end, main challenges and research gaps are identified, which should be the focuses of future research.

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In order to establish cancer-type-specific electroporation protocols for breast cancer, electroporation was performed in vitro in two modalities: in-suspension and adhered cells. Electroporation of cell suspensions was carried out through commercial electroporation cuvettes whereas a novel electrode for electroporation of adhered cells was designed and manufactured aimed to preserve cell structure, to provide a closer model to an in vivo scenario, and as a means to visualize the mechanical effects of electroporation on the cell membrane by using scanning electron microscopy. Electroporation protocols and electric field thresholds were predicted in silico and experimentally tuned through propidium iodide uptake and cell viability. Three breast-cancer cell lines (BT-20, MCF-7 and HCC1419) and a non-cancerous cell line (BEAS-2B) were used. Cancerous cells responded differently to electroporation depending on the electric parameters, cell histology, the cell culture modality, and the cell morphology (membrane thickness mainly), which was evaluated trough confocal and transmission electron microscopy. Particularly, it was found that electrochemotherapy may represent a promising alternative as an adjuvant treatment of metastatic breast tumours, and as a neoadjuvant therapy for Her2/neu tumours. Oppositely, triple negative breast tumours may show a high sensitivity to electroporation and therefore, they could be efficiently treated with irreversible electroporation. On the other hand, noncancerous cells demanded the highest voltage in both cell culture modalities in order to be electroporated. Hence, these cells in suspension may provide a reliable, easy-to-perform, low-cost model for the development of electroporation protocols for eradication of healthy tissue around a tumour in a safety margin.

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For the first time, the operational feasibility of the solar photo-Fenton process at neutral pH in continuous flow has been tested for three consecutive days. The aim of the treatment was to remove of contaminants of emerging concern (CECs) from wastewater treatment plant secondary effluents. To this end, a 5 cm-deep raceway pond reactor was run in continuous flow mode and the degradation of the CECs present in real secondary effluents was monitored at their natural concentrations. To keep dissolved iron at neutral pH, ethylenediamine-N,N'-disuccinic acid (EDDS) was used to form the complex Fe(III):EDDS as an iron source for the photo-Fenton reactions. At pilot scale the effects of the Fe(III):EDDS molar ratio (1:1 and 1:2) and hydraulic residence time (HRT) (20 and 40 min) on CEC removal were studied. The best operating condition was 20 min of HRT, giving rise to a treatment capacity of 900 L m-2 d-1 with CEC removal percentages of around 60%. The reactant concentrations were 0.1 mM Fe(III):EDDS at a 1:1 M ratio and 0.88 mM H2O2. Under these operating conditions, the short-term stability of the process was also demonstrated, thus pointing out the potential of this solar technology as a tertiary treatment.

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This paper represents a first approach in the study of photoreactor selection to treat industrial wastewater using solar photo-Fenton. In this context, simulated textile industry effluent containing a mixture of four dyes at different initial dissolved organic carbon (DOC) concentrations (45, 90, 180 and 270 mg/L) was treated by using three different solar reactor geometries: (i) tubular (5 cm diameter) provided with compound parabolic collector (ii) tubular (5 cm diameter) provided with flat collector and (iii) open channels forming raceway ponds with two liquid depths (5 and 15 cm). For comparison purposes, mineralisation percentages over 75% and chronic toxicity reduction were set as treatment goals. Regardless of the initial DOC concentration, negligible differences in terms of treatment time and hydrogen peroxide consumptions were found between the flat collector and compound parabolic collector photoreactors. Conversely, the treatment in the raceway pond reactors always resulted in higher values. In spite of this, when the photoreactors were compared in terms of treatment capacity (mg of DOC removed/m2 min) the raceway pond reactor at 15 cm of liquid depth presented the best results, with values as much as two or three times higher than those of the tubular reactors, except for the wastewater with 270 mg of DOC/L for which the raceway pond reactor at 5 cm liquid depth became the best option. When the treatment capacity is modified to include the photoreactor investment (mg of DOC removed/€ m2) the differences between the raceway pond reactor at both liquid depths and the photoreactors with solar collectors increased by as much as two orders of magnitude, which demonstrates the potential application of the former for the treatment of industrial wastewater by solar photo-Fenton.

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The main purpose of this pilot plant study was to compare degradation of five microcontaminants (MCs) (antipyrine, carbamazepine, caffeine, ciprofloxacin and sulfamethoxazole at 100 µg/L) by solar photo-Fenton mediated by EDDS and solar/Fe:EDDS/S2O82-. The effects of the Fe:EDDS ratio (1:1 and 1:2), initial iron species (Fe(II) or Fe(III) at 0.1 mM) and oxidizing agent (S2O82- or H2O2 at 0.25-1.5 mM) were evaluated. The higher the S2O82- concentration, the faster MC degradation was, with S2O82- consumption always below 0.6 mM and similar degradation rates with Fe(II) and Fe(III). Under the best conditions (Fe 0.1 mM, Fe:EDDS 1:1, S2O82- 1 mM) antipyrine, carbamazepine, caffeine, ciprofloxacin and sulfamethoxazole at 100 µg/L where 90% eliminated applying a solar energy of 2 kJ/L (13 min at 30 W/m2 solar radiation <400 nm). Therefore, S2O82- promotes lower consumption of EDDS as Fe:EDDS 1:1 was better than Fe:EDDS 1:2. In photo-Fenton-like processes at circumneutral pH, EDDS with S2O82- is an alternative to H2O2 as an oxidizing agent.

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In the context of a regional Chilean project (FIC Taltape project, BIP code 30158422-0), a multi-effect distillation (MED) pilot plant has been built and installed in a small community in the north of Chile (Taltape, Arica) in order to supply treated water for agricultural and domestic purposes. The aim of this paper is to assess the techno-economic feasibility of this system for supplying water with the required quality to the population. The characterization of the feed water and the effluents from the MED pilot plant (distillate and brine), obtained during five months of operation, has been firstly performed. Then, the prediction of the operation of the water treatment system with solar energy has been carried out using a typical meteorological year and the design of a static solar field that cover the thermal energy needs of the water treatment plant. The annual simulations of the MED pilot plant operating with solar energy showed that the water needs can be mostly covered using a static solar thermal field with a total area of 113.2 m2, which would generate roughly 46% of the total heat required by the water treatment plant. The technical analysis has been completed with an exhaustive economic assessment. The specific water costs have been determined for the MED pilot plant and the scale factor when the productivity is increased up to 5000 m3/day has been evaluated. The cost of distillated water produced by the MED plant varied from 15.0 USD$/m3 for the 10 m3/day production capacity to 1.25 USD$/m3 when this variable is increased to 5000 m3/day.

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This study evaluates the combined effect of photo-catalyst concentration and irradiance level on photo-Fenton efficiency when this treatment is applied to industrial wastewater decontamination. Three levels of irradiance (18, 32 and 46W/m2) and three iron concentrations (8, 20 and 32mg/L) were selected and their influence over the process studied using a raceway pond reactor placed inside a solar box. For 8mg/L, it was found that there was a lack of catalyst to make use of all the available photons. For 20mg/L, the treatment always improved with irradiance indicating that the process was photo-limited. For 32mg/L, the excess of iron caused an excess of radicals production which proved to be counter-productive for the overall process efficiency. The economic assessment showed that acquisition and maintenance costs represent the lowest relative values. The highest cost was found to be the cost of the reagents consumed. Both sulfuric acid and sodium hydroxide are negligible in terms of costs. Iron cost percentages were also very low and never higher than 10.5% while the highest cost was always that of hydrogen peroxide, representing at least 85% of the reagent costs. Thus, the total costs were between 0.76 and 1.39€/m3.

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The purpose of this work was to study the ozonation of nanofiltration (NF) retentates of real municipal wastewater treatment plant (MWTP) effluents for removal of microcontaminants (MCs) and toxicity. MCs present in these effluents were monitored using LC-MS/MS. Acute and chronic toxicity was addressed with Daphnia magna, Vibrio fischeri and Selenastrum capricornutum. Up to 40 MCs were found, most of them in concentrations over 100ng/L. 90% degradation of the sum of MCs was the critical point of comparison. When the NF membrane system was applied to MWTP effluents, treatment of NF rejection needed 2.75-4.5g O3/m3,4.5g O3/m3, which is less than 50% of the ozone needed for direct treatment of MWTP effluent. Treatment time (lower than 11min) was not influenced by MCs concentration, at least in the range tested (25-190µg/L). It has been demonstrated that consumption of ozone increased with organic load and inorganic content of different real effluents. MCs were eliminated by ozonation but acute toxicity (against V. fischeri and D. magna) increased. Chronic toxicity results were different and contrary in D. magna and S. capricornutum, due to the generation of new transformation products more toxic to D. magna than the parent contaminants. S. capricornutum inhibition percentage decreased in all cases after ozonation treatment. According to these results, before ozonation is implemented in MWTPs for the removal of MCs, the transformation products must first be examined and the treatment time or ozone doses should be extended to complete degradation if necessary.

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Industrial preparation of cork consists of its immersion for approximately 1 hour in boiling water. The use of herbicides and pesticides in oak tree forests leads to absorption of these compounds by cork; thus, after boiling process, they are present in wastewater. Cork boiling wastewater shows low biodegradability and high acute toxicity involving partial inhibition of their biodegradation when conventional biological treatment is applied. In this work, a treatment line strategy based on the combination of advanced physicochemical technologies is proposed. The final objective is the reuse of wastewater in the cork boiling process; thus, reducing consumption of fresh water in the industrial process itself. Coagulation pre-treatment with 0.5 g/L of FeCl3 attained the highest turbidity elimination (86 %) and 29 % of DOC elimination. Similar DOC removal was attained when using 1 g/L of ECOTAN BIO (selected for ozonation tests), accompanied of 64 % of turbidity removal. Ozonation treatments showed less efficiency in the complete oxidation of cork boiling wastewater, compared to solar photo-Fenton process, under the studied conditions. Nanofiltration system was successfully employed as a final purification step with the aim of obtaining a high-quality reusable permeate stream. Monitoring of unknown compounds by LC-QTOF-MS allowed the qualitative evaluation of the whole process. Acute and chronic toxicity as well as biodegradability assays were performed throughout the whole proposed treatment line.

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Sharp-force injuries are injuries caused by a mechanical force using sharp objects against the skin. Sharp-force injuries are mainly classified as stab, incised, chop, and therapeutic wounds and are less frequent than blunt-force injuries in animals. The analysis of the edges of the wound is crucial, especially if more than one type of lesion is involved. It may be difficult to differentiate between sharp trauma and blunt trauma, because lacerations can resemble incised wounds. The accurate documentation and examination of these injuries may indicate the instrument involved, the relationship between the animal and the perpetrator, and the force of the stab. Situations in which this type of trauma occurs may involve social violence, accidents, hunting, veterinary medical management, and religious rituals. The causes of death related to this type of trauma include hypovolemic shock, pneumothorax, or asphyxiation due to aspiration of blood. Necropsy findings should provide objective and unbiased information about the cause and manner of death to aid the investigation and further judgment of a possible crime.

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BACKGROUND: Metaplasic carcinoma of the breast was initially described by Huvos in 1974. It is a rare and aggressive entity characterized by the presence of mesenchymal and epithelial components. OBJECTIVE: To know the incidence and biologic behaviour of the metaplasic carcinoma of the breast at the Instituto de Enfermedades de la Mama, FUCAM, AC. METHODS: Data on women diagnosed with metaplasic carcinoma of the breast between January 2005 and December 2014 was collected by retrospectively reviewing in FUCAM. Clinical, pathological and immunohistochemical characteristics were assessed. The five-year disease-free survival (DFS) and overall survival (OS) were evaluated. RESULTS: a total of 4198 patients have been diagnosed with breast cancer in our institution, 40 (0.95%) of them with metaplasic carcinoma. The median age of the patients was 46 years (27-73). 60% of the patients were diagnosed with an advanced clinical stage (III) and the triple-negative subtype was the most frequently found. A mean follow-up of 24 months showed rates of overall survival and disease-free survival of 80% and 69.9%, respectively. The presence of both, cytokeratins 5/6 and p63, seems to have a negative impact in local recurrence. CONCLUSION: this study demonstrates that metaplasic carcinoma is a rare and aggressive disease. Expression of both tumor cytokeratins was associated with a worse outcome.

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Background: Breast cancer is the leading cause of cancer death in women in Mexico, is a heterogeneous disease, and knowledge of prognostic factors are critical in making treatment decisions. Objetive: determine the overall survival (OS) and disease-free survival (DFS) at 5 years, analyzed by risk groups. Material and methods: Patients diagnosed with breast treated at the Institute of Breast Diseases FUCAM from July 2005 to December 2014 were included. Simple frequencies were used for analysis of the general characteristics, and 5- year OS and DFS were analyzed using Kaplan-Meier curves. A subset analysis of the clinical stage and comparing survival in those patients diagnosed by mammography screening program was performed. Results: 4,902 patients with breast cancer were included, general clinical and pathological features are described and 3,762 patients were included for analysis of 5-year OS and DFS. The average age at diagnosis was 53.7 years; 13.3% were <40 years, which deleteriously reflects on the supervivencia global 76 vs 84% in >40. At diagnosis predominated locally advanced stages (45%), OS and DFS at 5 years was 96.8 ± 0.6% and 93.4%±0.9 respectively for early stages, 74.6 ± 1.7% and 68.7 ± 2% for locally advanced and 35.9 ± 5.1% and 37.4 ± 10.3% for metastatic tumors. Women diagnosed in the screening program had significantly better OS and DFS compared with symptomatic patients (95 and 93% vs 79 and 77%). For biological subtypes, OS and DFS was 89 and 84% for luminal, 81 and 81% for luminal Her +, 74 and 78% for pure Her 2, and 69 and 73% for triple negative. Conclusion: Knowledge of the prognostic factors that affect survival of patients with breast cancer is essential for categorizing risk groups and to individualize treatment in order to improve life expectancy.

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In view of the inefficient elimination of micro-pollutants by today's conventional biological treatments and new legislation requiring elimination of at least 80 % of their concentration, the application of an advanced tertiary treatment must be studied. A good option would be advanced oxidation processes (AOPs), which have very often been combined with physicochemical pre-treatSments to increase efficiency or reduce operating costs. This study focused on the combination of membrane nanofiltration and solar photo-Fenton for the main purpose of removing five pharmaceuticals (sulfamethoxazole, ibuprofen, ofloxacin, carbamazepine and flumequine) from real MWTP effluents under realistic conditions (µg L(-1)). This research also included tests performed with modified photo-Fenton using a low iron concentration at circumneutral pH and a low hydrogen peroxide dose, in an attempt to reduce major treatment costs. Over 80 % of dissolved organic carbon, chemical oxygen demand and turbidity were also retained during nanofiltration, making pharmaceutical removal less efficient in terms of concentrate treatment time than direct treatment, i.e. the concentrate illumination time was around 150 min while direct treatment was around 40 min. Nevertheless, it should be highlighted that, although no savings in installation costs was observed for the combined system (nanofiltration/solar photo-Fenton), the reaction rate improved and so, there was a savings in reagent costs (mainly hydrogen peroxide and sulfuric acid).

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In recent years, membrane technologies (nanofiltration (NF)/reverse osmosis (RO)) have received much attention for micropollutant separation from Municipal Wastewater Treatment Plant (MWTP) effluents. Practically all micropollutants are retained in the concentrate stream, which must be treated. Advanced Oxidation Processes (AOPs) have been demonstrated to be a good option for the removal of microcontaminants from water systems. However, these processes are expensive, and therefore, are usually combined with other techniques (such as membrane systems) in an attempt at cost reduction. One of the main costs in solar photo-Fenton comes from reagent consumption, mainly hydrogen peroxide and chemicals for pH adjustment. Thus, in this study, solar photo-Fenton was used to treat a real MWTP effluent with low initial iron (less than 0.2 mM) and hydrogen peroxide (less than 2 mM) concentrations. In order to work at neutral pH, iron complexing agents (EDDS and citrate) were used in the two cases studied: direct treatment of the MWTP effluent and treatment of the concentrate stream generated by NF. The degradation of five pharmaceuticals (carbamazepine, flumequine, ibuprofen, ofloxacin and sulfamethoxazole) spiked in the effluent at low initial concentrations (µg L(-1)) was monitored as the main variable in the pilot-plant-scale photo-Fenton experiments. In both effluents, pharmaceuticals were efficiently removed (>90%), requiring low accumulated solar energy (2 kJUV L(-1), key parameter in scaling up the CPC photoreactor) and low iron and hydrogen peroxide concentrations (reagent costs, 0.1 and 1.5 mM, respectively). NF provided a clean effluent, and the concentrate was positively treated by solar photo-Fenton with no significant differences between the direct MWTP effluent and NF concentrate treatments.

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The optimal photocatalyst concentration for industrial wastewater treatment in current photoreactor designs is several hundreds of milligrams per liter. However, the elimination of emerging contaminants (ECs), which are present at extremely low concentrations in waste water treatment plants (WWTP) effluents might be accomplished at much lower catalyst (TiO(2)) concentrations. One of the main drawbacks of reducing catalyst loading below the optimum is the loss of useful photons which instead are transmitted through the TiO(2) suspension without being absorbed by the catalyst. Accordingly, in this work, laboratory and solar pilot-scale experiments were performed with real WWTP effluents to evaluate the kinetics of photocatalytic degradation of 52 emerging contaminants under realistic (ppb) concentrations. The analysis of the samples was accomplished by solid phase extraction (SPE) followed by liquid chromatography-mass spectrometry (LC-MS). In view of the results, low concentrations of TiO(2) of the order of tens of milligrams per liter were found to be insufficient for the degradation of the ECs in photoreactors with a short light-path length (29 cm). However, it was established that solar reactors of diameters of several hundreds of millimetres could be used for the efficient removal of ECs from WWTP effluents. The results presented show a general methodology for selecting the most efficient reactor diameter on the basis of the desired catalyst concentration.

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This study aimed to determine the reliability and accuracy of the ICDAS and radiographs in detecting and estimating the depth of proximal lesions on extracted teeth. The lesions were visible to the naked eye. Three trained examiners scored a total of 132 sound/carious proximal surfaces from 106 primary teeth and 160 sound/carious proximal surfaces from 140 permanent teeth. The selected surfaces were first scored visually, using the 7 classes in the ICDAS. They were then assessed on radiographs using a 5-point classification system. Reexaminations were conducted with both scoring systems. Teeth were then sectioned and the selected surfaces histologically classified using a stereomicroscope (×5). Intrareproducibility values (weighted kappa statistics) for the ICDAS for both primary and permanent teeth were >0.9, and for the radiographs between 0.6 and 0.8. Interreproducibility values for the ICDAS were >0.85, for the radiographs >0.6. For both primary and permanent teeth, the accuracy of each examiner (Spearman's correlation coefficient) for the ICDAS was ≥0.85, and for the radiographs ≥0.45. Corresponding data were achieved when using pooled data from the 3 examiners for both the ICDAS and the radiographs. The associations between the 2 detection methods were measured to be moderate. In particular, the ICDAS was accurate in predicting lesion depth (histologically) confined to the enamel/outer third of the dentine versus deeper lesions. This study shows that when proximal lesions are open for inspection, the ICDAS is a more reliable and accurate method than the radiograph for detecting and estimating the depth of the lesion in both primary and permanent teeth.

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