Table 3: Comparison between Multi-strand wire (MS) and Ortho-Flex-Tech™ wire (OFT) retainer groups, in terms of the plaque index (PI), Gingival index (GI) and Calculus index (CI) of the mandibular anterior teeth. Means, standard deviation, 95% Confidence intervals, Median and interquartile.

	MS wire Mean (SD) [95% CI]	OFT wire Mean (SD) [95% CI]	P-value	Median	25 - 75 quartiles	95% CI of the Difference
PI buccal surface	0.17 (0.38) [0.01-0.33]	0.12 (0.31) [-0.01-0.26]	0.573	0.12	0.00 - 0.43	-0.36 - 0.29
PI lingual surface	0.61 (0.84) [0.26-0.96]	0.33 (0.71) [0.02-0.65]	0.091	0.13	0.00 - 0.47	-0.18 - 0.68
PI mesial surface	0.64 (0.74) [0.33-0.95]	0.43 (0.64) [0.15-0.72]	0.367	0.17	0.00 -0.88	-0.20 - 0.62
PI distal surface	0.61 (0.66) [0.33-0.89]	0.41 (0.52) [0.18-0.64]	0.223	0.25	0.00 - 0.71	-0.16 - 0.56
GI buccal surface	0.69 (0.78) [0.34-1.07]	0.49 (0.59) [0.18-0.76]	0.338	0.25	0.00 -1.13	-0.21 - 0.62
GI lingual surface	1.09 (0.78) [0.82-1.56]	1.46 (0.33) [1.24-1.68]	0.283	1.43	0.92 -1.67	-0.73 - 0.004
GI mesial surface	0.87 (0.79) [0.54-1.29]	1.11 (0.69) [0.84-1.48]	0.326	1.21	0.12 - 1.67	-0.68 - 0.21
GI distal surface	0.92 (0.96) [0.52-1.33]	1.14 (0.96) [0.71-1.56]	0.484	1.33	0.00 - 2.00	-0.78 - 0.36
CI buccal surface	0.00 (0.00)	0.00 (0.00)	1.000	0.00	0.00 - 0.00	-
CI lingual surface	0.21 (0.59) [-0.04-0.46]	0.27 (0.77) [-0.07-0.61]	0.880	0.00	0.00 - 0.00	-0.47 - 0.34

Mann-Whitney U test.