穿山甲 (Manis aurita) の顎口腔系の感覚・運動機構の比較解剖学的特性に関する研究
第1報・咀嚼筋の筋紡錘分布
1984 年 51 巻 4 号 p. 674-688
[Correction] J. Stomatol.Soc.,Jpn. Vol.52 No.1 (1985) pp.43a-43a
[Correction] J. Stomatol.Soc.,Jpn. Vol.52 No.1 (1985) pp.43b-43b詳細
1984 年 51 巻 4 号 p. 674-688
[Correction] J. Stomatol.Soc.,Jpn. Vol.52 No.1 (1985) pp.43a-43a
[Correction] J. Stomatol.Soc.,Jpn. Vol.52 No.1 (1985) pp.43b-43b
In order to understand the phylogenetic change of the jaw movement mode of the mammals, it is quite necessary to define the neuromuscular mechanism relative to the feeding habit proper to the toothless animals (e. g. Pangolin) . Three specimens were examined. The serial celloidin frontal and horizontal sections, 30 to 40μm thick, were stained with hematoxylin and eosin.
1. The masseter arises from the incomplete zygomatic arch, consisting of the maxillary bone, connective tissue cord and squamosal bone. It passes downwards and backwards to the cylindrical jaw bone (to the neck of the condyle) . The muscle is composed of 2 bellies, the superficial and profound, which contain 48 muscle spindles (52%) and 34 spindles (36%), respectively.
2. The temporalis is rudimentary, composed only of the small vertical belly, arising from the posterior part of the zygomatic arch and the wall of the temporal fossa, being inserted into the jaw above the mandibular foramen. It contains 11 spindles (12%) .
3. The pterygoideus lateralis arises from the wall of the infratemporal fossa. It passes backwards and is inserted into the condyle, forming two heads. It is devoid of spindles.
4. The pterygoideus medialis is absent.
5. The intermandibularis is well developed, forming the floor of the mouth and extending backwards beyond the TMJ. It is devoid of spindles.
