Background The field of dental ceramics for CAD-CAM is enriched with a new innovative material composition having a porous three-dimensional structure of feldspathic ceramic infiltrated with acrylic resins.The aim of this study is to determine the mechanical properties of Polymer-Infiltrated-Ceramic-Network (PICN) and compare its performance with other ceramics and a nano-ceramic resin available for CAD-CAM systems. Material and Methods In this study a total of five different materials for CAD-CAM were investigated. A polymer-infiltrated ceramic (Vita Enamic), a nano-ceramic resin (Lava Ultimate), a feldspathic ceramic (Mark II), a lithium disilicate ceramic (IPS-e max CAD) and finally a Leucite based ceramic (Empress - CAD). From CAD-CAM blocks, 120 bars (30 for each material cited above) were cut to measure the flexural strength with a three-point-bending test. Strain at failure, fracture stress and Weibull modulus was calculated. Vickers hardness of each material was also measured. Results IPS-EMAX presents mechanical properties significantly better from the other materials studied. Its strain at failure, flexural strength and hardness exhibited significantly higher values in comparison with the others. VITA ENAMIC and LAVA ULTIMATE stand out as the next most resistant materials. Conclusions The flexural strength, elastic modulus similar to a tooth as well as having less hardness than ceramics make PICN materials an option to consider as a restorative material. Key words:Ceramic infiltrated with resin, CAD-CAM, Weibull modulus, flexural strength, micro hardness.

The objective of the study was to evaluate the in vivo effectiveness of two fluorescence techniques (DIAGNOdent and VistaProof) and of visual and tactile evaluation in the diagnosis of occlusal caries in permanent teeth. A total of 302 teeth (molars and premolars) from 152 patients were studied. The occlusal surfaces were cleaned using pumice mixed with water, followed by application of the diagnostic methods according to the instructions of the manufacturer, and of the visual and tactile methods according to the recommendations. The true extent of the lesions was determined by fissurotomy. The sensitivity and specificity of visual diagnosis were 79 and 72 %, respectively, versus 53 and 98 % in the case of tactile diagnosis. Teeth with caries lesions exhibited significantly higher DIAGNOdent and VistaProof scores than those without caries. Using the optimum cutoff point of 23.5 obtained in our study for DIAGNOdent, sensitivity and specificity were found to be 92.4 and 92.7 %, respectively, while values of 88.1 and 95.1 % were obtained with a cutoff point of 28.5. Sensitivity in the case of the VistaProof system varied between 92.9 % (cutoff point 1.05) and 85.3 % (cutoff point 1.3), with respective specificity values of 95.8 and 88.6 %. The areas under the curve were 0.756, 0.759, 0.954 and 0.965 for the visual and tactile methods and for DIAGNOdent and VistaProof, respectively. The fluorescence-based techniques showed greater internal and external validity than the visual and tactile methods in diagnosing occlusal caries in permanent teeth. VistaProof is the best method for diagnosing caries in its early stages.

The objective of this study was to evaluate the clinical ability of Near-Infrared Light-Transillumination (NILT) for approximal dentinal caries detection and to compare with direct digital-radiography (DDR), as well as to determine whether the combination of both techniques improves the diagnostic capacity of the lesions. From 88 patients (over 18 years), 138 posterior teeth (76 molars and 62 premolars), that had approximal caries reached into dentine determined by DDR, were included. Lesion extension and DDR images were scored as follows: D0 = sound surface, D1/D2 = caries restricted to the outer/inner-half of the enamel, and D3/4 = caries restricted to the outer/inner-half of the dentin. Opening of the approximal surface using 0.5 mm-in-diameter diamond-bar was used as gold-standard. The lesion extension was then determined by the following criteria: no dentinal caries (D0/1/2) or dentinal caries (D3/4). Seventy-one lesions were D3 and 67 lesions were D4. Sensitivities of overall/D3/D4 were 98.0/95.7/100.0 (NILT) and 100/100/100 (DDR), respectively. Correlations with gold-standard were 0.92 (NILT) and 0.42 (DDR), respectively. The correlation increased to 0.97 (p = 0.045) on combining NILT and DDR. There was no difference in sensitivity between the methods (p > 0.05); but was differences in the correlation (p < 0.01). It can be concluded that NILT showed sensitivity similar to that of DDR and higher correlation than DDR for approximal dentinal caries detection. Accordingly, it may be used to monitor the progression of caries without exposing the patient to ionizing radiation, this being of particular interest in growing patients and in pregnant women. In this respect, NILT can be an effective diagnostic tool adjunctive to bitewing radiographs in detecting approximal dentinal caries. The combination of NILT and DDR represents an increase in the diagnosis of approximal lesions The proposed diagnostic protocol comprises visual examination, followed by NILT and DDR only if the former technique detects approximal caries.

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Background In recent years the early detection of such caries has gained importance, since it may avoid unnecessary dental tissue damage and allow minimally invasive dental treatment. A study is made of 5 systems for diagnosing caries: traditional visual and tactile methods, DIAGNOdent, VistaProof and CarieScan. Material and Methods A prospective study was made in the Department of Stomatology, Dental Pathology and Therapeutics Teaching unit of the University of Valencia (Valencia, Spain), involving the analysis of 32 teeth (molars or premolars of both arches scheduled for filling or for use as posts in dental bridges) in 28 patients. The following caries diagnostic methods were applied: visual, tactile, DIAGNOdent (KAvo, Biberach, Germany), VistaProof (Dürr Dental AG, Bietigheim-Bissingen, Germany) and CarieScan (IDMoS Dental Systems, Dundee, Scotland, United Kingdom). Fissurotomy was subsequently performed for histological validation. Results Visual inspection showed an area under the receiver operating characteristic curve (AUC-ROC) of 0.75, with a sensitivity and specificity of 0.75. Tactile diagnosis in turn showed AUC = 0.714, with maximum sensitivity (100%) and a specificity of 42.9%. DIAGNOdent (cutoff point 22.5) and VistaProof (cutoff point 1.1) showed AUC = 0.969, while CarieScan (cutoff point 21.5) presented AUC = 0.973. These latter three methods all had a sensitivity of over 92%. The specificity of DIAGNOdent was maximum, while that of CarieScan and VistaProof was 75%. Conclusions The emergent methods in the diagnosis of caries (DIAGNOdent, VistaProof and CarieScan) yielded similar results, and in all cases proved superior to the traditional visual and tactile methods. DIAGNOdent was seen to be the most effective technique, followed by CarieScan and VistaProof. Key words:Caries diagnosis, emergent diagnostic methods, fluorescence, electrical impedance, minimally invasive dentistry.