Erratum to: Clinical Oral Investigations

DOI 10.1007/s00784-016-2026-6

On page 6 of the published article, in the section “Statistical analysis” and paragraph (b) there should be the following formula: And in paragraph (c) the correct formula is SE instead of SE2

$$ w=\frac{N_a{N}_b}{N_a+{N}_b}, $$