Effect of low-level laser therapy on the time needed for leveling and alignment of mandibular anterior crowding

To assess the effect of low-level laser therapy (LLLT) on overall leveling and alignment time of mandibular anterior crowding and associated pain after initial archwire placement.

Thirty-two females (18-25 years) with mandibular anterior crowding were randomly allocated into laser and control groups. Eligibility criteria included Angle Class I molar relationship and Little's irregularity index (LII) from 4 to 10 mm. Randomization was accomplished with a computer-generated random list. A 0.014-inch copper-nickel-titanium (Cu-NiTi) wire was inserted immediately after bonding of 0.022-inch Roth brackets followed by 0.016-inch Cu-NiTi, 0.016 × 0.022-inch NiTi then 0.017 × 0.025-inch stainless steel wire after completion of alignment. In-Ga-As laser was applied to the mandibular anterior segment in the laser group on days 3, 7, and 14, then at 1 month followed by every 2 weeks until completion of leveling and alignment. Visual analogue scale questionnaires were completed by each patient over 7 days from initial archwire placement. Digital models were used to monitor changes in the irregularity index. Blinding was applicable for outcome assessors only.

The mean time for leveling and alignment was significantly lower in the laser compared to the control group (68.2 ± 28.7 and 109.5 ± 34.7 days, respectively). The laser group displayed a significantly higher mean alignment improvement percentage as well as lower pain scores compared to the control group.

Within the constraints of the current study, LLLT has a potential for acceleration of anterior segment alignment as well as reduction of the pain associated with placement of initial archwires.