Quality of thermoplasticized and single point root fillings assessed by micro-computed tomography

Abstract Background The objective of the present micro-computed tomography (micro-CT) study was to assess the presence of voids in band-shaped isthmuses obturated using three different filling techniques. Methods Twenty-four artificial molar teeth with a band-shaped isthmus were allocated to three groups (n = 8) for obturation, according to the filling technique: single-cone (SC), continuous wave of condensation (CWC) or lateral condensation (LC). Obturation was performed with gutta-percha (GP) cones and iRoot SP (Innovative Bioceramix, Vancouver, Canada). Post-filling micro-CT scanning was performed. The percentage of filling materials and void volumes were calculated in the isthmus areas and data were analyzed using one-way ANOVA and Tukey tests. Results The mean percentage of void volumes and corresponding filling percentages in the isthmus areas after obturation in the SC groups was 22.98 % ± 1.19 %, 77.02 % ± 1.19 %; in the CWC groups 10.46 % ± 2.28 %, 89.54 % ± 2.28 %; and in the LC groups was 13.14 % ± 1.85 %, 86.86 % ± 1.85 %, respectively. Conclusions In band-shaped isthmus area, the obturation quality of CWC was superior to SC and LC techniques.

Download Full-text

Pretreatment and Freezing Rate Effect on Physical, Microstructural, and Nutritional Properties of Fried Sweet Potato

Transactions of the ASABE ◽

10.13031/trans.13099 ◽

2019 ◽

Vol 62 (1) ◽

pp. 45-59 ◽

Cited By ~ 2

Author(s):

Ahmed Rady ◽

Andrew Giaretta ◽

Adedeji Akinbode ◽

Mathew Ruwaya ◽

...

Keyword(s):

Computed Tomography ◽

Vitamin C ◽

Sweet Potato ◽

Freezing Rate ◽

Micro Computed Tomography ◽

Surface Pretreatment ◽

X Ray ◽

C 30 ◽

Fat Uptake

Abstract. Sweet potato is a unique high-calorie food because it is an excellent source of some essential micronutrients, such as provitamin A (ß-carotene). The quality of par-fried frozen sweet potato products is impacted by several factors that have not been well researched, such as freezing rate and surface modification. In this study, our objective was to evaluate the effect of freezing rate (at -20°C, -30°C, -40°C, and -60°C), surface pretreatment including blanching and gum coating (methylcellulose, sodium alginate, or mixed gums), sample dimensions (strips or slices), and cultivar (Covington and Murasaki) on several quality attributes of fried sweet potato. Based on our study, frying at 180°C yielded the lowest oil content among the tested temperatures. Compared with Covington samples, Murasaki strips coated with mixed gums produced fried samples that were significantly (p = 0.05) lower in fat uptake (10.84%), less porous (35.5%), crispier (maximum force = 6.90 N), lighter, less red, and yellower. Higher freezing rate, 5.12°C min-1 (at -60°C), showed significantly lower fat content, and lower lightness or yellowness than lower freezing rates. Frying at 180°C significantly reduced vitamin C and ß-carotene levels from 3.75 mg and 349.27 µg per 100 g to 1.92 mg and 105.99 µg per 100 g, respectively. X-ray micro-computed tomography showed a significant decrease in porosity because of high freezing rates. The general conclusion is that faster freezing rate is better for par-fried sweet potato quality preservation. Keywords: ß-carotene, Fat uptake, Gum coating, Par-frying, Sweet potato, X-ray micro-computed tomography, Vitamin C.

Download Full-text