Mandibular movement during sleep bruxism associated with current tooth attrition

Access this Article

Search this Article

Author(s)

    • Okura Kazuo
    • Department of Stomatognathic Function and Occlusal Reconstruction, Subdivision of Clinical Dentistry, Division of Oral Science, Institute of Biomedical Sciences, Tokushima University Graduate School
    • Shigemoto Shuji
    • Department of Stomatognathic Function and Occlusal Reconstruction, Subdivision of Clinical Dentistry, Division of Oral Science, Institute of Biomedical Sciences, Tokushima University Graduate School
    • Suzuki Yoshitaka
    • Department of Stomatognathic Function and Occlusal Reconstruction, Subdivision of Clinical Dentistry, Division of Oral Science, Institute of Biomedical Sciences, Tokushima University Graduate School|Faculté de Médecine Dentaire, Université de Montréal
    • Noguchi Naoto
    • Department of Oral Treatment and Clinical Education, Tokushima University Hospital
    • Omoto Katsuhiro
    • Department of Stomatognathic Function and Occlusal Reconstruction, Subdivision of Clinical Dentistry, Division of Oral Science, Institute of Biomedical Sciences, Tokushima University Graduate School
    • Abe Susumu
    • Department of Oral Treatment and Clinical Education, Tokushima University Hospital
    • Matsuka Yoshizo
    • Department of Stomatognathic Function and Occlusal Reconstruction, Subdivision of Clinical Dentistry, Division of Oral Science, Institute of Biomedical Sciences, Tokushima University Graduate School

Abstract

<p><i>Patient:</i> Observation of attrition patterns suggests that mandibular movement in sleep bruxism (SB) may be associated with current tooth attrition. The aim of this study was to confirm this phenomenon by investigating mandibular movement and masseter muscle activity. The subject was a healthy 21-year-old Japanese male. We recorded biological signals including mandibular movement and masseter electromyograms (EMGs) with a polysomnograph. Based on the EMG using Okura's criteria, SB events were classified into clenching, grinding and mixed types according to mandibular movement criteria. The close-open mandibular movement cycles (CO-cycles) during grinding and mixed type events were selected based on mandibular movement trajectories.</p><p><i>Discussion:</i> Fifty-eight CO-cycles were selected in seven grinding and three mixed types. We found that SB mandibular movements associated with current tooth attrition. Excessive lateral movements (ELM) beyond the canine edge-to-edge position were observed in the closing (10.3%) and opening (13.8%) phases of the CO-cycle. Total masseter muscle activity was significantly higher during voluntary grinding (VGR) than during CO-cycle including ELM (working side: <i>P</i> = 0.036, balancing side: <i>P</i> = 0.025). However, in the middle and late parts of the opening phase, working side masseter muscle activity was significantly higher during CO-cycle including ELM than during VGR (<i>P</i> = 0.012). In the early part of the closing phase, balancing side masseter muscle activity was significantly higher during CO-cycle including ELM than during VGR (<i>P</i> = 0.017).</p><p><i>Conclusion:</i> These findings suggest that excessive forceful grinding during ongoing SB events may have caused canine attrition in this patient.</p>

Journal

  • Journal of Prosthodontic Research

    Journal of Prosthodontic Research 61(1), 87-95, 2017

    Japan Prosthodontic Society

Codes

Page Top