Compensatory dentoalveolar supraeruption and occlusal plane cant after botulinum-induced hypotrophy of masticatory closing muscles in juvenile rats

Ji Wook Choi, Hak Jin Kim, Joo Won Moon, Sang Hoon Kang, Hye Jin Tak, Sang Hwy Lee

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


Objective: The purpose of this study was to investigate changes in the dentoalveolus and occlusal plane associated with the hypotrophy of unilateral masticatory muscles following botulinum toxin (BTX) treatment in the juvenile period of rats. Design: We hypothesized that the loss of functional loading of masticatory muscles and occlusal force invites compensatory dentoalveolar supraeruption, accelerating occlusal cant and skeletal asymmetry. In order to confirm this hypothesis, six-week-old male rats (N = 5) were treated with BTX simultaneously at the unilateral masseter, temporalis, and medial pterygoid muscles, with a booster injection after six weeks for the experimental group. The control group (N = 6) had saline injections on both sides at the same sites and on the same schedule. Results: After 12 weeks, masseter and medial pterygoid muscles on the BTX side showed hypotrophic change. The mandibular structure was asymmetrical, with decreased size and lateral tilting. The maxillary and mandibular molars were supraerupted from the Frankfort plane or mandibular inferior border with lateral tilt. They accompanied downward occlusal plane cant resulting from the supraerupted maxillary and mandibular molars on the BTX side. The dentoalveolar structural changes included diminished alveolar bone density, narrow periodontal ligament space, and disorganized distribution of periodontal collagen fiber. Conclusions: Unilateral hypotrophy of masticatory muscles affected the growth, symmetry, and structure of the skeletal jaws and dentoalveolus. Our hypothesis about the dentoalveolar compensation, that muscular hypotrophy was closely integrated with dentoalveolar supraeruption and an inclined occlusal plane, was confirmed.

Original languageEnglish
Pages (from-to)34-42
Number of pages9
JournalArchives of Oral Biology
Publication statusPublished - 2019 May

Bibliographical note

Funding Information:
This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government ( 2017R1A2B4005319 ) for S.-H. Lee.

Publisher Copyright:
© 2019 Elsevier Ltd

All Science Journal Classification (ASJC) codes

  • Otorhinolaryngology
  • Dentistry(all)
  • Cell Biology


Dive into the research topics of 'Compensatory dentoalveolar supraeruption and occlusal plane cant after botulinum-induced hypotrophy of masticatory closing muscles in juvenile rats'. Together they form a unique fingerprint.

Cite this