Purpose: The aim of this study was to clarify the effect of wearing an oral
appliance on the range of motion of the spine during trunk flexion in
elite-level athletes. Method: Participants were 15 elite-level female handball players (24.9 ± 2.0
years). A single-layer mouthguard was fabricated using a 2.0-mm-thick
thermoplastic sheet that all teeth were adjusted to make even contact upon
light clenching. Spinal curvature was measured in the static standing posture
and standing forward-bending posture by using a spinal shape analyzer. The evaluation indices were thoracic kyphosis angle
(TKA), lumbar lordosis angle (LLA),
sacral inclination angle (SSA), and spinal inclination angle (SIA).
Measurements were made under three conditions: mandibular resting position
(RP), clenching in the intercuspal position (ICP), and clenching while wearing
a mouthguard (MG). Differences in spinal curvature due to occlusal conditions
were compared using repeated measure analysis of variance. Results: LLA,
SSA, and SIA showed significant differences between RP and ICP, and between RP
and MG, with RP having the greatest range of motion. There was no significant
difference in any spinal alignment between ICP and MG. TKA was not
significantly affected by occlusal condition. Conclusion: This study was
clarified that lumbar lordosis angle, sacral inclination angle, and spinal
inclination angle during trunk flexion decreased with clenching, regardless of the presence or absence of an oral
appliance. Therefore, it was suggested
that clenching contributes to trunk stabilization and may affect flexibility.
References
[1]
Bando, Y., Takahashi, M., Fukui, T., Maruyama, A., & Sugita, M. (2019). Relationship between Occlusal State and Posture Control Function of Trampoline Gymnasts. Journal of Sports Dentistry, 23, 14-20.
[2]
Ghamkhar, L., & Kahlaee, A. H. (2019). The Effect of Trunk Muscle Fatigue on Postural Control of Upright Stance: A Systematic Review. Gait Posture, 72, 167-174.
https://doi.org/10.1016/j.gaitpost.2019.06.010
[3]
Robert, S., & Amanda, B. (2019). Fascia in Sport and Movement. In K. Takeuchi, (Ed.), Anatomy Trains in Motion (pp. 47-62). Round Flat.
[4]
Takahashi, M., & Bando, Y. (2018). Relationship between Occlusal Balance and Agility in Japanese Elite Female Junior Badminton Players. International Journal of Sports Dentistry, 11, 34-42.
[5]
Takahashi, M., Bando, Y., Fukui, T., Maruyama, A., & Sugita, M. (2021). Effect of Clenching on Spinal Alignment in Normal Adults. International Journal of Dentistry and Oral Health, 8, 386. https://doi.org/10.16966/2378-7090.386
[6]
Takahashi, M., Bando, Y., Fukui, T., Maruyama, A., & Sugita, M. (2023a). Equalization of the Occlusal State by Wearing a Mouthguard Contributes to Improving Postural Control Function. Applied Sciences, 13, 4342. https://doi.org/10.3390/app13074342
[7]
Takahashi, M., Bando, Y., Fukui, T., Maruyama, A., & Sugita, M. (2023b). Straight Jump Landing Position of Trampoline Gymnasts with Stable Occlusal Balance Reflects Standing Postural Control Function. Applied Sciences, 13, 6689.
https://doi.org/10.3390/app13116689
[8]
Takahashi, M., Bando, Y., Fukui, T., Maruyama, A., & Sugita, M. (2023c). Influence of Occlusion on Flight Time in Trampoline Competition. International Journal of Dentistry and Oral Health, 9, 405. https://doi.org/10.16966/2378-7090.405
[9]
Takahashi, M., Bando, Y., Kitaoka, K., & Kimura, S. (2020). Influence of Occlusal State on Posture Control and Physical Fitness of Elite Athletes: Examination Targeting Female Handball Players. Journal of Sports Dentistry, 24, 18-25.
[10]
Thomas, W. M. (2016). Anatomy Trains. In H. Itaba, & S. Ishii, (Eds.), Superficial Front Line (3nd ed., pp. 107-126), Lateral Line (pp. 127-144), Deep Front Line (pp. 201-228). Igaku-Shoin.