* Effect of LED-mediated-photobiomodulation therapy on orthodontic tooth movement and root resorption in rats.
- The aim of this experimental study was to evaluate the effects of light-emitting diode-mediated-photobiomodulation therapy (LPT), on the rate of orthodontic tooth movement (TM) and orthodontically induced root resorption, in rats. Twenty male 12-week-old Wistar rats were separated into two groups (control and LPT) and 50 cN of force was applied between maxillary left molar and incisor with a coil spring. In the treatment group, LPT was applied with an energy density of 20 mW/cm(2) over a period of 10 consecutive days directly over the movement of the first molar teeth area. The distance between the teeth was measured with a digital caliper on days 0 (T0), 10 (T1), and 21 (T2) on dental cast models. The surface area of root resorption lacunae was measured histomorphometrically using digital photomicrographs. Mann-Whitney U and Wilcoxon tests were used for statistical evaluation at p < 0.05 level. TM during two different time intervals (T1-T0 and T2-T1) were compared for both groups and a statistically significant difference was found in the LPT group (p = 0.016). The TM amount at the first time period (1.31 ± 0.36 mm) was significantly higher than the second time period (0.24 ± 0.23 mm) in the LPT group. Statistical analysis showed significant differences between two groups after treatment/observation period (p = 0.017). The magnitude of movement in the treatment group was higher (1.55 ± 0.33 mm) compared to the control group (1.06 ± 0.35 mm). Histomorphometric analysis of root resorption, expressed as a percentage, showed that the average relative root resorption affecting the maxillary molars on the TM side was 0.098 ± 0.066 in the LPT group and 0.494 ± 0.224 in the control group. Statistically significant inhibition of root resorption with LPT was determined (p < 0.001) on the TM side. The LPT method has the potential of accelerating orthodontic tooth movement and inhibitory effects on orthodontically induced resorptive activity.
=>初めて, 最初の, 第一の, はじめに, 最初, 第1
Overview of noun first
The noun first has 6 senses (first 4 from tagged texts)
1. (9) first, number one -- (the first or highest in an ordering or series; "He wanted to be the
first")
2. (5) first, number one, number 1 -- (the first element in a countable series; "the first of the
month")
3. (1) beginning, commencement, first, outset, get-go, start, kickoff, starting time, showtime,
offset -- (the time at which something is supposed to begin; "they got an early start"; "she knew
from the get-go that he was the man for her")
4. (1) first base, first -- (the fielding position of the player on a baseball team who is stationed
at first of the bases in the infield (counting counterclockwise from home plate))
5. first, first-class honours degree -- (an honours degree of the highest class)
6. first gear, first, low gear, low -- (the lowest forward gear ratio in the gear box of a motor
vehicle; used to start a car moving)
Overview of adj first
The adj first has 6 senses (first 5 from tagged texts)
1. (232) first -- (preceding all others in time or space or degree; "the first house on the right";
"the first day of spring"; "his first political race"; "her first baby"; "the first time"; "the
first meetings of the new party"; "the first phase of his training")
2. (61) first, 1st -- (indicating the beginning unit in a series)
3. (4) inaugural, initiative, initiatory, first, maiden -- (serving to set in motion; "the
magazine's inaugural issue"; "the initiative phase in the negotiations"; "an initiatory step toward
a treaty"; "his first (or maiden) speech in Congress"; "the liner's maiden voyage")
4. (4) beginning, first -- (serving to begin; "the beginning canto of the poem"; "the first verse")
5. (3) first, foremost, world-class -- (ranking above all others; "was first in her class"; "the
foremost figure among marine artists"; "the top graduate")
6. first -- (highest in pitch or chief among parts or voices or instruments or orchestra sections;
"first soprano"; "the first violin section"; "played first horn")
Overview of adv first
The adv first has 4 senses (first 4 from tagged texts)
1. (58) first, firstly, foremost, first of all, first off -- (before anything else; "first we must
consider the garter snake")
2. (40) first, for the first time -- (the initial time; "when Felix first saw a garter snake")
3. (9) first -- (before another in time, space, or importance; "I was here first"; "let's do this
job first")
4. (4) foremost, first -- (prominently forward; "he put his best foot foremost")
--- WordNet end ---