Table 2: Statistical data of the measured Ra values of surface roughness (nm).

Step	Median	Minimum	Maximum	Interquartile range
Untreated	263.25	194.76	504.02	152.5
After resin infiltration	185.78	134.23	504.69	178.06
After 1st thermocycling	177.76	97.76	614.41	207.74
After 2nd thermocycling	168.5	108	433	67.05
Control untreated	179.72	70.94	268.09	197.15
Control after 1st thermocycling	145.22	89.45	239.58	150.13
Control after 2nd thermocycling	115.8	82.47	199.49	117.01