Occlusal caries detection on 3D models obtained with an intraoral scanner. A validation study.

OBJECTIVES: To evaluate the diagnostic performance of visual caries assessment on 3D dental models obtained using an intraoral scanner and to compare it with the performance of the clinical visual inspection. METHODS: Fifty-three permanent posterior teeth scheduled for extraction were randomly selected and included in this study. One to three independent examination sites on the occlusal surface of each tooth were clinically inspected using International Caries Detection and Assessment System (ICDAS) criteria. Afterwards, the examined teeth were scanned intraorally with a 3D intraoral scanner (TRIOS 4, 3Shape TRIOS A/S, Copenhagen, Denmark) using white and blue-violet light (415 nm wavelength) to capture the colour and fluorescence signal from the tissues. Six months after the clinical examination, the same examiner conducted the on-screen assessment of the obtained 3D digital dental models at the selected examination sites using modified ICDAS criteria. Both tooth colour and fluorescence texture with high resolution were assessed. Lastly, an independent examiner conducted the histological examination of all teeth after extraction. Using histology as the reference test, Sensitivity (SE), Specificity (SP), Accuracy (ACC), area under the Receiver Operating Characteristic (ROC) curve, and Spearman's correlation coefficient were calculated for the clinical and on-screen ICDAS assessments. RESULTS: The ACC values of the evaluated methods varied between 0.59-0.79 for initial caries lesions and 0.77-0.99 for moderate-extensive caries lesions. Apart from SE values corresponding to caries in the inner half of enamel, no significant difference was observed between clinical visual inspection and on-screen assessment. In addition, no difference was found in the assessment of 3D models with tooth colour alone or supplemented with fluorescence for all the evaluated diagnostic measures. CONCLUSIONS: On-screen visual assessment of 3D digital dental models with tooth colour or fluorescence showed a similar diagnostic performance to the clinical visual inspection when detecting and classifying occlusal caries lesions on permanent teeth. CLINICAL SIGNIFICANCE: 3D intraoral scanning can aid the detection and classification of occlusal caries as part of patient screening and can potentially be used in remote caries assessment for clinical and research purposes.

In vivo validation of Diagnodent and Vista proof devices vs ICDAS clinical criteria on incipient carious lesions in adults.

AIM: This study aimed to validate the in vivo performance of Diagnodent and Vista proof devices with ICDAS clinical criteria on incipient carious lesions in adults. METHODS: A total of 44 adult patients with 230 incipient occlusal caries took part in the present study. These patients were assessed for caries with ICDAS clinical criteria, and then they were examined with Diagnodent pen™ (DP) and Vista proof™ (VP) fluorescence devices. Sensitivity, specificity accuracy, and ICC agreement between devices with ICDAS criteria, which served as a gold standard, were evaluated. RESULTS: Regarding the caries diagnostic devices, sensitivity and specificity found 0,61 and 0,51 for DP, and 0,64 and 0,54 for VP, respectively. The different detection methods showed no differences in diagnostic capacity (Az values) each other, and ICC values with ICDAS criteria were calculated low. CONCLUSIONS: DP and VP do not contribute to incipient occlusal carious lesions' better detective ability compared with visual ICDAS clinical criteria. The DP and VP devices presented no differences in diagnostic ability and measured lesion depth concerning the visual examination.

Clinical Evaluation of Two Different Prevention Programs in Adults Depending on Their Caries Risk Profile: One-year Results.

The aim of this study was to investigate the management of incipient caries lesions in adults with two preventive protocols. A total of 44 adult patients with high, moderate and low caries risk with 516 incipient caries took part in the study. These patients were assessed for caries with International Caries Detection and Assessment System (ICDAS) criteria and were then divided into three groups depending on their caries risk profile: a high-risk group (group A), a moderate-risk group (group B), and a low-risk group (group C). Participants in each group were further divided randomly into two subgroups. In subgroups A1, B1, and C1, an intensive preventive protocol was applied, while in subgroups A2, B2, and C2, the protocol consisted only of instructions in oral hygiene. The invasive-intensive protocol included the topical application of fluoride, brushing with 5000-ppm fluoride toothpaste, use of amorphous calcium phosphate-casein phosphopeptide, applications of sealants for occlusal lesions (ICDAS code 2), and minimal resin restorations for occlusal lesions (ICDAS code 3). There was no statistically significant difference in the number of lesions (baseline and after one year) in the high-risk and moderate-risk groups that received the intensive protocol (groups A1 and B1), while the control groups were statistically significant different (groups A2 and B2). In the low-risk group, there was no statistically significant difference in the number of lesions (groups C1 and C2). The two different preventive protocols in the high- and moderate-risk groups presented differences in effectiveness, while in the low-risk group, no significant difference was demonstrated.

Setting characteristics of a resin infiltration system for incipient caries treatment.

OBJECTIVES: This study investigated the curing efficiency, the extent of atmospheric oxygen inhibition to the polymerization reaction and the mechanical properties of a new resin-infiltration system for caries treatment. METHODS: The curing efficiency was estimated by measuring the percentage degree of cure (%DC) of thin resin films (h: 150µm, Ø: 5mm, n=3), 10min after 40s exposure to a quartz halogen bulb (750mW/cm2) light curing unit (Optilux 501, Demetron/Kerr, USA), in the absence of O2, by micro ATR-FTIR spectroscopy. The extent of O2 inhibition on resin film setting (width in µm) was assessed by transmission optical microscopy on thin films (h: 150µm, Ø: ∼7mm, n=5) placed between two transparent cover slips and exposed to air from lateral sites. For each sample the extent of inhibition was measured at 5 different locations. The mechanical properties were tested employing Instrumented Indentation Testing according to ISO 14577:2002. Resin specimens (h: 2mm, Ø: 10mm, n=5) were prepared employing cylindrical teflon moulds enclosed in transparent matrix strips and glass slides as before. The measurements were performed employing a Vickers indenter attached to a universal hardness testing machine (ZHU2.5/Z2.5 plus test Xpert software, Zwick/Roell, Ulm, Germany). The parameters tested were Martens Hardness (MH), Vickers Hardness (VHN), Indentation Elastic Modulus (EIT) and elastic to total ratio of indentation work (ηIT). For all these tests, specimens of a conventional light-curing bonding resin (HB-Heliobond, Ivoclar-Vivadent, FL) prepared as above were used as control. Student t-test was used to identify statistically significant differences between the two materials in the parameters tested (a: 0.05). RESULTS: The results of the materials tested were: (a) [% DC]; IC: 57.4±1.5, HB: 59.8±2.4, (b) [Width of O2 inhibition/µm]; IC: 33.1±6.5, HB: 23.6±4.4, (c) [MH/N/mm(2)] IC; 116±16, HB: 261±35, (d) [VHN]; IC; 15.4±2.5, HB: 22.1±1.8, (e) [EIT/(GPa)]; IC; 2.3±0.4, HB: 7.5±0.5, and (g) [ηIT (%)] IC; 50.3±3.4, HB: 35.1±1.9. The IC presented no significant difference in terms of % DC, higher thickness of the inhibited layer, lower MH, VHN, EIT and greater ηIT values than HB. CONCLUSIONS AND CLINICAL SIGNIFICANT: The resin-infiltrating system for incipient caries treatment demonstrated the same curing efficiency with a conventional unfilled bonding resin, but exhibited higher extent of oxygen inhibition, lower hardness, lower elastic modulus and higher plastic to elastic indentation energy.

Cervical dentin hypersensitivity: a cross-sectional investigation in Athens, Greece.

The purpose of this study was to identify the prevalence of cervical dentin hypersensitivity in a cross-sectional investigation of Greek adults. Seven hundred and sixty-seven subjects were examined. Participants were patients processed for first examination in the Clinic of Oral Diagnosis and Radiology at the Faculty of Dentistry, University of Athens. The evaluation of hypersensitivity was performed using two methods: for each tooth, the response to a) tactile stimulus and b) air-blast stimulus was measured. Additional factors such as smoking habits, oral health behaviour, consumption of acidic foods, type of toothbrush, daily use of fluoride solution and of desensitising toothpaste, gingival recession and non-carious cervical lesions were recorded and evaluated as causative factors. Descriptive statistics on the demographics of the study sample, of oral health behaviour characteristics and of oral examination findings were performed. Comparisons of these characteristics in the presence or absence of hypersensitivity were conducted with the chi-square test. Data were further analysed using multiple logistic regression modelling. Among study participants, 21·3% had at least one cervical dentin hypersensitivity reaction to the tactile stimulus, and 38·6%, to the air-blast stimulus. Multivariate analysis detected association of the hypersensitivity in tactile or air-blast stimulus with the non-carious lesions and with the gingival recessions. Additionally, a relation between hypersensitivity and air-blast stimulus with gender (female) was found. There was no association between the hypersensitivity in both of the stimuli and the level of education, smoking, consumption of acidic foods, type of toothbrush and daily use of fluoride solution or desensitising toothpaste. The overall prevalence of cervical dentin hypersensitivity in the adult population in Athens ranged from 21·3% to 38·6% depending on the type of stimuli. Cervical non-carious lesions and gingival recessions were determined as significant predictors of dentin hypersensitivity.

The impact of magnification on occlusal caries diagnosis with implementation of the ICDAS II criteria.

AIM: This study compared the impact of low-powered magnification on the detection of occlusal caries. METHODS: The occlusal surfaces of 38 extracted teeth received caries ICDAS classification with and without magnification by two examiners. Histology was used as the gold standard. RESULTS: No significant differences existed in terms of sensitivity, specificity, LR+, LR- and Az values for the two examiners and modalities. Interexaminer agreement was almost perfect for grades 0, 2, 3 irrespective of magnification. For grade 1, magnification resulted in lower agreement than unaided vision. CONCLUSION: Magnification does not improve the detective performance of visual examination.

Decision-making and preventive non-surgical therapy in the context of a European Core Curriculum in Cariology.

This paper is part of a series of papers towards a European Core Curriculum in Cariology for undergraduate dental students. The European Core Curriculum in Cariology is the outcome of a joint workshop of the European Organisation for Caries Research (ORCA) together with the Association for Dental Education in Europe (ADEE), which was held in Berlin from 27 to 30 June 2010. The present paper covers decision-making and non-surgical treatment. In particular, it will provide some background information on this part of the European core curriculum. The dentist, on graduation, must be competent at applying the principles of prevention of dental hard tissue disease processes (primary prevention) and progression when it has manifested itself (secondary prevention). The competences should apply in differing ways to patients of all ages. Goals of prevention should be clearly defined in order for outcomes to be evaluated, and a dentist should be competent at determining these outcomes. Although this concept is recognised by many academics and experts, clinical teaching, practice and health insurance coverage frequently emphasise surgical treatment. There are many reasons and obstacles that might account for this, and this paper suggests some reasons why this might be and makes suggestions for how these can be addressed in the future. One factor that is essential in the provision of a preventive, non-surgical approach is that of communication with the patient. However, this unfortunately takes less space in the dental curricula compared with technical skills aimed at restorative procedures; this weighting needs to be more equally balanced.

Diagnostic performance of the visual caries classification system ICDAS II versus radiography and micro-computed tomography for proximal caries detection: an in vitro study.

OBJECTIVES: The purpose of this study was: (a) to compare the visual caries classification system ICDAS II with conventional (CR) and digital radiography (DR) for diagnosis of non-cavitated caries on free proximal surfaces, (b) to examine the potential of micro-computed tomography (MCT) to substitute histological examination for the in vitro caries assessment. METHODS: Both proximal surfaces of 20 teeth received classification separately by two examiners by means of the diagnostic modalities examined. The teeth were sectioned and assessed for depth of the lesion. The modalities were compared in terms of degree of inter-examiner agreement, sensitivity, specificity, accuracy, positive and negative predictive value and validity. Two diagnostic thresholds were applied: no caries versus all caries scores (D1), and no dentin caries versus dentin caries (D3). RESULTS: The weighted kappa values for inter-examiner reproducibility for all diagnostic modalities were 0.51-0.81. Visual examination (ICDAS II) reached significant higher sensitivity (0.92-0.96) and negative predictive value (0.9-1) than radiography. Likewise, the radiographic modalities presented significantly higher specificity (0.93-1) and positive predictive values (0.92-1) than the ICDAS II criteria. The overall accuracy performance of radiographic modalities was related to the diagnostic threshold. MCT did not agree with histological validation at each disease severity scale. CONCLUSIONS: The ICDAS II criteria are a promising tool for caries diagnosis on free proximal surfaces. DR and CR radiography present comparable performance. Furthermore, MCT is not capable of constituting a reliable alternative to histological examination for caries research.

Corticosterone-regulated actions in the rat brain are affected by perinatal exposure to low dose of bisphenol A.

The estrogen-mimicking endocrine disrupter bisphenol A (BPA) which is used in the manufacture of plastic and epoxy resins, is one of the world's most heavily produced synthetic chemicals. BPA is detected in animal tissues, and its bio-accumulation has shown to be higher in the fetus than the mother. Exposure to doses below the daily safe limit has been reported to affect the sexual differentiation of the brain and modify the behavior of the exposed rodent offspring. The aim of the present study was to investigate in the rat the possible organizational effects of low BPA exposure on glucocorticoid-regulated responses. Female breeders were exposed to 40 microg/kg b.w. BPA daily throughout pregnancy and lactation. Plasma corticosterone levels and the two types of hippocampal corticosteroid receptors (GR and MR) were determined in mid-adolescent offspring under basal conditions and following a Y-maze task. BPA treated females had higher corticosterone levels than control females and BPA males and lower GR levels than BPA males, under basal conditions. Following the mildly stressful experience of Y-maze, corticosterone levels were increased in BPA-treated animals of both sexes, compared to the controls. GR levels were also increased in BPA-treated females compared to males. No effect of BPA was observed on MR levels, whereas the Y-maze experience significantly decreased receptors' levels in both female groups. The animals' performance in the task was also evaluated. BPA exposure significantly impaired the spatial recognition memory in both sexes, and modified the behavioural coping in a sex-dependent manner. Female BPA-treated offspring exhibited increased "anxiety-like" behaviour and dramatic loss of exploration attitude during the task, in comparison to males. This study provides for the first time evidence that corticosterone and its actions in the brain are sensitive to the programming effects of BPA at a dose below the currently acceptable daily intake.

Evaluation of surface characteristics of dental composites using profilometry, scanning electron, atomic force microscopy and gloss-meter.

The aim of this in vitro investigation was to compare various roughness and topography measurement methods to characterize the surface quality in several types of resin composites. The initial surface quality of several resin composites was compared. The materials evaluated were of three categories: i) hybrid: TPH Spectrum; ii) reinforced microfill: Micronew and iii) microhybrid: Synergy Duo, Esthet-X, Point.4 and Palfique Estelite. Three Groups of identical disk-shaped specimens (10 x 1.5 mm) were prepared from each material (n = 6) and polished with Soflex discs. Macro-roughness (Ra) was measured with Group 1 by 2-D profilometry. Atomic Force Microscopy (AFM) gave 3-D images and micro-roughness (Ra) of Group 2. Surface optical gloss at 60 degrees was determined for Group 3. Specimens of each material were also studied by scanning electron microscopy. Macro-Ra values (microm) ranged from 0.30 to 0.56. Micro-Ra values ranged from 0.03 to 0.14 and they differed from macro-Ra values in ranking order. Percentage Gloss values ranged from 30.6 to 70.1%. The results revealed that micro-roughness showed a high correlation with gloss values (r = 0.93), whilst macro-roughness did not (r = 0.62). Moreover, the AFM method showed higher capability to distinguish surface roughness compared with the 2-D profilometry and to reveal more detailed definition of surface texture than the examination under SEM.

Parallels between tooth development and repair: conserved molecular mechanisms following carious and dental injury.

The reparative mechanisms that operate following carious and traumatic dental injury are critical for pulp survival and involve a series of highly conserved processes. It appears that these processes share genetic programs-linked to cytoskeletal organization, cell movement, and differentiation-that occur throughout embryogenesis. Reactionary dentin is secreted by surviving odontoblasts in response to moderate stimuli, leading to an increase in metabolic activity. In severe injury, necrotic odontoblasts are replaced by other pulp cells, which are able to differentiate into odontoblast-like cells and produce a reparative dentin. This complex process requires the collaborative efforts of cells of different lineage. The behavior of each of the contributing cell types during the phases of proliferation, migration, and matrix synthesis as well as details of how growth factors control wound cell activities are beginning to emerge. In this review, we discuss what is known about the molecular mechanisms involved in dental repair.

Marginal and internal adaptation of Class II ormocer and hybrid resin composite restorations before and after load cycling.

To overcome the shortcomings of the conventional composite restorative materials, ormocer materials have been introduced over the past few years. The purpose of this study was to evaluate the marginal and internal adaptation of two ormocer restorative systems (Admira, Voco and Definite, Degussa) compared to a hybrid composite one (TPH Spectrum, Dentsply/ DeTrey), before and after load cycling in Class II restorations. Standardized Class II restorations with cervical margins on enamel were divided into three groups ( n=16). Teeth of each group were filled with one of the restoratives tested and its respective bonding agent. Each group was divided into two equal subgroups. The marginal and internal adaptation of the first subgroup was evaluated after 7-day water storage at room temperature and of the second after cyclic loading in a mastication simulator (1.2x10(6) cycles, 49 N, 1.6 Hz). The occlusal and cervical marginal evaluation was conducted by videomicroscope and ranked as "excellent" and "not excellent". One thin section (150 microm), in mesial-distal direction, of each restoration, was examined under metallographic microscope to determine the quality of internal adaptation. The occlusal and cervical adaptation of both ormocer restorative systems was similar and clearly worse compared with the hybrid composite restorative one before as well as after load cycling. Concerning internal adaptation, no gap-free ormocer restorations were detected, whereas all Spectrum restorations presented perfect adaptation. The bonding agents of the ormocers formed layers with unacceptable features (pores, fractures) whereas that of the hybrid composite achieved perfect bonding layer even after loading. The rheological characteristics of the bonding agents of the ormocer restorative systems are proposed to be responsible for their inferior marginal and internal quality in Class II restorations compared with the hybrid composite one.

In vitro characterization of two laboratory-processed resin composites.

PURPOSE: To compare various characteristics of two new-generation laboratory-processed resin composites (BelleGlass HP/SDS-Kerr and Sinfony/3M-ESPE). The properties evaluated were degree of C=C conversion, microhardness, roughness, biaxial flexural strength and polymerization shrinkage-strain. MATERIALS AND METHODS: All specimens were subjected to a first and a second polymerization cycle according to the manufacturers' instructions. The degree of C=C conversion (DC) was recorded on rectangular (3 x 2 x 0.5mm(3)) specimens (n=3) by FT-IR micromultiple internal reflectance spectroscopy immediately after each of the two polymerization cycles. Twenty cylindrical specimens (10 x 2mm(2)) of each material were prepared for surface microhardness (n=10, VHN, 200 g load, 20s) and surface roughness (n=10, Ra) measurements. The biaxial flexural strength and stiffness were determined on disk-shaped (n=8, 15 x 0.7 mm(2)) specimens loaded to fracture at 1 mm/min crosshead speed. The polymerization shrinkage-strain was calculated with the bonded-disk method. All values were statistically analyzed by Student's unpaired t-test (p<0.05). RESULTS: The second polymerization cycle significantly increased the degree of C=C conversion for both materials (p<0.05). BelleGlass HP exhibited significantly higher degree of C=C conversion, surface microhardness, surface roughness, biaxial flexural strength and stiffness values compared to Sinfony (p<0.05). SIGNIFICANCE: Several differences exist between the materials although both products are recommended for the same clinical applications.