Effect of Low-Level Laser Therapy on Bone Regeneration in Midpalatal Suture after Rapid Maxillary Expansion


  • Furkan Dindaroğlu
  • Gökhan Önçağ
  • Sultan Ölmez
  • Servet Doğan
  • Özlem Gümrükçü-Ertürk

Received Date: 17.06.2011 Accepted Date: 13.07.2011 Turk J Orthod 2011;24(2):83-96


The aim of this study is to evaluate the effects of low level laser therapy (LLLT) on bone regeneration in the midpalatal suture after rapid maxillary expansion.

Subjects and Methods:

The study sample comprised thirteen patient aged between 10 and 15 years old with maxillary transverse deficiency (> 5 mm) and bilateral or unilateral posterior crossbite were included. All patients underwent rapid maxillary expansion with the use of Hyrax expander and subjects were divided into 2 groups: control group (n=15) and laser group (n=15). The patient's parents were instructed to activate Hyrax expander by turning the screw one turn in the morning and another turn in the evening. A diode laser (3 W, = 810 nm, 9=3,5 cm2) was used. The laser was applied in 5 sessions with intervals of 48 hours. The laser was applied in continuous mode and for the 15 seconds at each point. The delivered energy was 45 j and energy density was 13 j/cm2. The laser probe was placed behind the singulum of incisors. Multi-slice low dose Computer tomography scans were taken 1,5 months later after final laser application in laser groups and 3 months later in control group. Density was measured in Hounsfield unit.


The difference in bone density of midpalatal suture between control and laser group was not statistically significant (p > 0.05). Bone density in midpalatal suture of two sample groups is almost equal as Hounsfield Unit.


Low level laser therapy shortens retention period, accelerates bone regeneration in midpalatal suture during rapid maxillary expansion. Evaluated in terms of bone ossification in the median suture, 3 months of stability could be achieved after 1.5 months. Low level laser application after rapid maxillary expansion can play an active role on the retention time and stability.

Keywords: Low level laser therapy, Rapid maxillary expansion, Bone density, Retention