Comparing Circumferential Supracrestal Fiberotomy with Surgical Scalpel Versus Photobiomodulation in Orthodontic Relapse Reduction: A Clinical Trial

Objective: This investigation aimed to compare the efficacy of circumferential supracrestal fiberotomy (CSF) with surgical scalpel, laser CSF, and photobiomodulation for reduction of relapse after orthodontic tooth rotation. Background: Relapse is the tendency of teeth to move back to their preoperative position after removal of orthodontic appliances. Materials and methods: This randomized controlled clinical trial was conducted on 90 rotated teeth at the final stages of fixed orthodontic treatment. The teeth were randomly divided into six groups (n = 15) of (1) control (no intervention), (2) photobiomodulation alone (wavelength of 940 nm, 0.2 W, and 4 J/cm2), (3) conventional CSF, (4) laser CSF (wavelength of 940 nm, 1.5 W, and 4 J/cm2, and power density of 160 mW/cm2), (5) conventional CSF plus photobiomodulation, and (6) laser CSF plus photobiomodulation. Measurements were made on clinical photographs and dental casts using the AutoCAD software. Level of pain of patients was measured within the first 24 h after fiberotomy using a visual analog scale. Data were analyzed by ANOVA and Kruskal-Wallis test (α = 0.05). Results: The magnitude (p = 0.014) and percentage (p = 0.035) of relapse were significantly different among the six groups, and they were the highest in the control group followed by photobiomodulation alone, laser CSF, conventional CSF, conventional CSF plus photobiomodulation, and finally, laser CSF plus photobiomodulation. Moreover, photobiomodulation plus laser CSF and photobiomodulation plus conventional CSF had significantly different results from the other groups. The six groups had no significant difference in sulcus depth changes, gingival recession (difference in primary and secondary crown height), or pain score (p > 0.05). Conclusions: This study suggests that utilizing photobiomodulation combined with laser CSF or conventional CSF can be effective in reducing relapse. However, further clinical trials are required to support this idea. Iranian Registry of Clinical Trials (IRCT20210621051653N1).

Molecular biological and histological effects of Er:YAG laser irradiation on tooth movement

The aim of this study was to evaluate the effects of a fiberotomy-like procedure using Er:YAG laser irradiation on the velocity of orthodontic tooth movement. To produce experimental tooth movement in rats, orthodontic force was applied to the upper first molars with a nickel-titanium closed coil. The right molars were irradiated with an Er:YAG laser while the non-irradiated left molars were used as controls. The rats were sacrificed at 4 weeks after the start of tooth movement and the distance between the mesial side of the second molar and the distal side of the upper first molar was measured on CT images. The amount of tooth movement was significantly greater in the irradiation group than in the control group. The TRAP-positive nuclei count at the pressure site was higher in the laser-irradiation group than in the control group. Expression of RANKL and ALP was higher at the mesial-coronal pressure site in the laser-irradiation group than in the control group. In addition, expression of OPG was higher at the pressure site in the control group than in the laser-irradiation group. These results suggest that a fiberotomy-like procedure using an Er:YAG laser stimulates osteoclasts and osteoblasts and may promote bone metabolism in the context of experimental tooth movement.

Fiberotomy enhances orthodontic tooth movement and diminishes relapse in a rat model

OBJECTIVES

Accelerated orthodontic tooth movement is triggered by procedures that include mucoperiosteum flap surgery and surgical scarring of cortical bone. Our aim was to test whether fiberotomy by itself will accelerate orthodontic tooth movement and diminish relapse.

MATERIALS AND METHODS

In 34 Wistar rats, alveolar bone resorption and molar tooth movement were measured after fiberotomy, apical full-thickness flap without detachment of gingiva from the roots, or no surgery. Orthodontic appliance was installed at time of surgery and activated for 14 days, generating movement of the first maxillary molar buccal and then removed.

RESULTS

Percent of sections in which alveolar bone resorption was detected was significantly higher (p < 0.05) after fiberotomy (27%) in comparison with apical flap surgery (12%) or no surgery (6%), after 30 days. Also, at the end of active phase, the molar moved significantly faster (p < 0.01) and twice the distance after fiberotomy (0.54 ± 0.33) in comparison with apical surgery (0.26 ± 0.12) or no surgery (0.3 ± 0.09). Sixteen days after the appliance was removed, only 12% relapse was recorded in the fiberotomy group, while almost total relapse in other two groups.

CONCLUSION

We conclude that fiberotomy solely accelerated orthodontic tooth movement and diminished relapse.