For an accurate assessment of jaw movement, it is crucial to understand the comprehensive formation of the masticatory muscles with special reference to the relationship to the disc of the temporomandibular joint. Detailed dissection was performed on 26 head halves of 14 Japanese cadavers in order to obtain precise anatomical information of the positional relationships between the masticatory muscles and the branches of the mandibular nerve. After complete removal of the bony elements, the midmedial muscle bundle in all specimens and the discotemporal muscle bundle in 6 specimens, derivatives of the temporalis, which insert into the disc were observed. On the anterior area of the articular capsule and the disc of the temporomandibular joint, the upper head of the lateral pterygoid, the midmedial muscle bundle of temporalis and the discotemporal bundle of temporalis were attached mediolaterally, and in 3 specimens the posterosuperior margin of the zygomaticomandibularis was attached to the anterolateral area of the disc. It is suggested that these muscles and muscle bundles contribute to various mandibular movements. Although various patterns of the positional relationships between the muscles and muscle bundles and the their innervating nerves are observed in the present study, relative positional relationships of the muscles and muscle bundles and of nerves of the mandibular nerve are consistent. A possible scheme of the developmental formation of the masticatory muscles based on the findings of the positional relationships between the muscles and the nerves is presented.

Positional relationships between the masticatory muscles and their innervating nerves with special reference to the lateral pterygoid and the midmedial and discotemporal muscle bundles of temporalis.

Anatomy of the rectourethralis muscle.

The masticatory muscles are generally described as the muscles that originate from the cranium and insert on the mandible. Some of the masticatory muscles also insert into the articular disc of the temporomandibular joint. Although there are numerous reports of studies on the attachment of the fibers to the disc, most reports discuss only one muscle. We have shown that the masticatory muscles are not simply a group of clearly independent muscles, but that these muscles contain various transitional muscle bundles among the major muscles. From this point of view, we carried out minute dissection of the collective muscles and muscle bundles surrounding the temporomandibular joint. We dissected 40 head halves of 20 Japanese cadavers (10 males, 10 females: average 79.6 yr). After complete removal of the bony elements, the structures surrounding the temporomandibular joint were investigated en-block. In all specimens, the superior surface of the upper head of lateral pterygoid and the midmedial muscle bundle were attached to the disc. In some specimens, the discotemporal bundle, zygomaticomandibularis, and masseter were attached to the anterior surface of the disc. The total vector of these muscles pulls the disc anteriorly. In contrast, the vector of the muscles to the condylar processes of the mandible pulls the mandible medially. From these observations, it seems that the fibers, which attach to the disc act to steady the disc against the masticatory movement.

An anatomical study of the muscles that attach to the articular disc of the temporomandibular joint.

INTRODUCTION: The medial portion of the infratemporal fossa (ITF) is not infrequently involved in sinonasal and skull base pathologies. However, endoscopic view of the ITF remains unclear with lack of studies addressing this region from the endoscopic perspective. METHODS: Using an extended endoscopic approach, the pterygopalatine and infratemporal fossae were dissected in 10 sides of five adult cadaver heads. A plane of dissection along the pterygoid base and the infratemporal surface of the greater sphenoid wing was developed. High-quality images were produced by coupling the video camera to a digital recording system. RESULTS: The foramen rotundum, ovale, and spinosum were accessed and new landmarks were described from the endoscopic point of view. The sphenomandibularis muscle was also highlighted. Maxillary and mandibular nerves and middle meningeal artery were all identified. Columellar measurements to the foramen rotundum and ovale ranged from 6.1 to 8.0 cm for the former and 7.0 to 9.1 cm for the latter, with a mean of 6.75 cm and 7.78 cm respectively. CONCLUSION: The current study provides a novel endoscopic orientation to the medial ITF. Such knowledge should provide an anatomical basis for experienced surgeons to endoscopically address this region with more safety and efficacy.

Endoscopic transnasal study of the infratemporal fossa: a new orientation.

Migraine and tension-type headaches have always plagued mankind. In spite of all the research dollars spent trying to determine the etiologies of these headaches, the neurology community still has not established a known cause of migraine and tension type headaches. This paper describes a study that was conducted for the U.S. Food and Drug Administration in which the efficacy of the Nociceptive Trigeminal Inhibition Tension Suppression System was evaluated and proved safe and efficacious in the reduction of medically diagnosed migraine and tension-type headache.

Migraine and tension-type headache reduction through pericranial muscular suppression: a preliminary report.

This study describes a hitherto unreported, functionally distinct craniomandibular muscle as observed in 25 cadaveric specimens and MRI scans of clinical patients. The muscle was consistently observed as originating from the maxillary surface of the sphenoid bone and inserting on the temporal crest (internal oblique line) of the mandible. This anatomic observation should broaden our understanding of craniomandibular function and may have clinical implications regarding retro-orbital pain.

Anatomical observation of a craniomandibular muscle originating from the skull base: the sphenomandibularis.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Dunn Gf

Author Tools

Chat about Author

Papers

Anatomical observation of a craniomandibular muscle originating from the skull base: the sphenomandibularis.