Comparison of anchorage reinforcement with temporary anchorage devices or a Herbst appliance during lingual orthodontic protraction of mandibular molars without maxillary counterbalance extraction

Table 2 Descriptive breakdown of velocity of protraction for both groups and for each individual protraction site

	Valid protraction sites (N)	Mean protraction distance (mm/month)	SD	Minimum	Maximum	Median
Herbst	22	0.51	0.19	0.17	0.89	0.51
TAD	14	0.35	0.15	0.17	0.63	0.33
All Groups	36	0.45	0.19	0.17	0.89	0.45

ISSN: 1746-160X