1 23 Lasers in Medical Science ISSN 0268-8921 Lasers Med Sci DOI 10.1007/s10103-012-1258-1 The effect of 810-nm low-level laser therapy on pain caused by orthodontic elastomeric separators Ladan Eslamian, Ali Borzabadi- Farahani, Aidin Hassanzadeh-Azhiri, Mohammad R. Badiee & Reza Fekrazad