En Bloc Removal of the Mandible, the Masticatory Muscles and the Mandibular Nerve in the Chimpanzee (Pan troglodytes, Blumenbach 1799), with a Review and Critique of the Methods Used to Expose the Trigeminal Musculature in Derived Primates

The detailed protocol of the en bloc removal of the mandible, the muscles supplied by the mandibular nerve tree and the maxillary artery is described in the chimpanzee (Pan troglodytes). This new method allows integrated observations of the masticatory muscles, their ontogenetic associates and the specific branches of the mandibular nerve that supply them. The topographic relationships of the muscles, including their subparts, are seen in light of the specific nerve branches that supply and interconnect them. Previous methods that examine parts of the trigeminal musculature and the mandibular nerve in a fragmented manner are described and critiqued. The present method allows us to arrive at a sounder classification of the trigeminal muscles based on the integrated observation of their nerve supply; this approach was first proposed by Toldt and more recently used by Tomo. The anatomical, functional, clinical, ontogenetic and phylogenetic aspects of the new approach are discussed.