Translucency of Human Dental Enamel

Translucency of human dental enamel was determined by total transmittance of wavelengths from 400 to 700 nm. The transmission coefficient at 525 nm was 0.481 mm-1. Total transmission of light through human dental enamel increased with increasing wavelength. Human tooth enamel is more translucent at higher wavelengths. The translucency of wet human enamel and enamel after dehydration was also measured by total transmittance. The transmission coefficient at 525 nm decreased from 0.482 to 0.313 mm-1 after dehydration and was reversed on rehydration. The decrease in translucency occurred as a result of the replacement of water around the enamel prisms by air during dehydration.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68115/2/10.1177_00220345810600100401.pd

The Detection of Incipient Caries with Tracer Dyes

The purpose of this study was to determine the increase in color contrast produced by the use of a tracer dye in detection of incipient caries lesions with transillumination. Twenty four caries-free first premolars were immersed in an acid gelatin for production of artificial incipient caries lesions. After the lesions had developed, these teeth were photographed by transillumination. Two photographs were taken of each tooth. The first photograph showed the lesion without dye. A blue tracer dye was then added and absorbed by the lesion, and a second photograph was taken. The data on the color difference were obtained by use of a reflectance colorimeter and showed a four-fold increase between the lesion and surrounding area with the dye. A two-way analysis of variance was used for the statistical interpretation. The color difference between the lesion without the dye and then with the dye was significant. The use of the blue tracer dye, therefore, significantly increased the contrast in the images of the artificial incipient lesions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68289/2/10.1177_00220345890680021101.pd

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Microleakage of four different restorative glass ionomer formulations in Class V cavities: Er:YAG laser versus conventional preparation

Objective: To investigate microleakage in class V cavities following restoration with conventional glass-ionomer cements (CGICs) or resin-modified glass-ionomer cements (RMGICs), following Er:YAG laser or conventional preparation. Background Data: The sealing ability of GICs in Er:YAG-lased cavities has not been studied extensively. Methods: Three hundred and twenty class V cavities were assigned to four groups: those in groups A and B were prepared using an Er: YAG laser, and those in groups C and D were conventionally prepared. In groups B and D the surface was additionally conditioned with cavity conditioner. Each group was subdivided according to the GIC used: groups 1 (Fuji II), 2 (Fuji IX), 3 (Fuji II LC) and 4 ( Fuji VIII). After thermocycling, the specimens were immersed in a 2% methylene blue solution, sectioned oro-facially, and analyzed for leakage. The effect of the conditioner was analyzed using a scanning electron microscope (SEM). Results: Significant differences between occlusal and gingival margins were found in all groups (p < 0.05) except B4, D3, and D4. Comparison of preparation methods (groups A-D) revealed significant differences at the occlusal margin in groups 1 and 3, but in all groups at the gingival margin (p < 0.05). Laser preparation without conditioning allowed more leakage (p < 0.05). Comparison of filling materials (groups 1-4) revealed significant differences in groups B and C at the occlusal margin, and in all groups at the gingival margin (p < 0.05). In these groups, laser-prepared cavities (with or without conditioning) restored with Fuji II LC and Fuji VIII showed the least leakage at both margins. Conclusion: RMGICs allowed less microleakage than CGICs. Complete marginal sealing was not achieved and conditioning is recommended