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Immunization of Alpacas (Lama pacos) with Protein Antigens and Production of Antigen-specific Single Domain Antibodies
Published on: January 26, 2019
Occlusal development and masseter activity in Alpacas (Lama pacos)
Susan H Williams1, Joanna Sidote, Kristin K Stover
1Department of Biomedical Sciences, Ohio University College of Osteopathic Medicine, Athens, Ohio 45701, USA. willias7@ohio.edu
Anatomical Record (Hoboken, N.J. : 2007)
|November 10, 2009
Summary
Changes in alpaca masseter muscle activity correlate with tooth eruption and occlusion development. Increased occlusal contacts alter chewing cycles and muscle recruitment patterns, suggesting a delayed adult motor pattern onset.
Area of Science:
- Mammalian masticatory system development
- Dental occlusion and jaw biomechanics
Background:
- Tooth eruption and the development of occlusion are key ontogenetic changes in mammalian masticatory systems.
- Understanding these changes is crucial for comprehending jaw muscle function during feeding.
Purpose of the Study:
- To test the hypothesis that masseter muscle activity changes correlate with increased occlusal contacts during alpaca dental development.
- To investigate electromyographic patterns of the superficial and deep masseter during different stages of dental maturation.
Main Methods:
- Electromyography (EMG) was used to record masseter activity in infant, juvenile, and adult alpacas (Lama pacos).
- Data were collected prior to and following first molar (m1) occlusion, and in adults with full permanent dentitions.
- Chewing cycle durations and muscle firing timing were analyzed and compared across developmental groups.
Main Results:
- Masseter activity and chewing cycle durations were similar in pre-m1 and post-m1 occlusion groups, with minor exceptions in deep masseter timing.
- The m2-m3 occlusion group showed significantly longer chewing cycles and later balancing-side deep masseter firing.
- Increased occlusion correlated with greater relative activity in working-side masseter muscles compared to balancing-side muscles.
Conclusions:
- While minor changes in masseter activation occur with early occlusion, increased molar contacts significantly alter chewing cycles and muscle recruitment patterns.
- Alpacas exhibit a relatively delayed onset of the adult motor pattern, potentially linked to occlusal changes from tooth eruption.
- Musculoskeletal development may also influence masseter activity, as seen in other mammals.
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