HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Full Text (PDF) Services Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by Korfage, J.A.M Articles by van Eijden, T.M.G.J. Search for Related Content PubMed PubMed Citation Articles by Korfage, J.A.M Articles by van Eijden, T.M.G.J.

Fiber-type Composition of the Human Jaw Muscles—(Part 2) Role of Hybrid Fibers and Factors Responsible for Inter-individual Variation

Department of Functional Anatomy, Academic Center for Dentistry Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands

View larger version (24K): [in a new window]   Figure 1. Distribution of pure and hybrid fiber types (mean ± SD) in the human jaw-closers (temporalis, masseter, pterygoids) and jaw-openers (mylohyoid, digastric, geniohyoid); SD values are a measure for inter-individual variability. Muscle samples (jaw-closers, 6 to 9 per muscle; jaw openers, 2 to 4 per muscle) were obtained from eight cadavers. Because the fiber-type distribution of the lateral pterygoid had more similarities with that of the jaw-closers than with that of the jaw-openers, this muscle was included among the group of jaw-closers. For more information, see Korfage et al.(2001). MyHC = myosin heavy-chain.

View larger version (32K): [in a new window]   Figure 2. Electrophoretic (A) and immunohistochemical (B) characterization of single human jaw-muscle fibers obtained from the digastric and temporalis. Consecutive fibers (1–5) were immunolabeled with antibodies against MyHC-IIA+IIX, MyHC-IIA, and MyHC-I. MyHC composition of fragments of the same fibers was determined by gel electrophoresis. Fiber types are: pure type I (1), pure type IIA (4), pure type IIX (5), and hybrid type IIA+IIX (2 and 3). In a total 218 fibers, 118 were classified as pure and 100 as hybrid fibers. In the hybrid fibers, all combinations of isoforms were found; the proportions of these isoforms varied greatly (for more details, see Korfage and Van Eijden, 2003b).