Chapter 17: Oral Cavity Anatomy Applied To Exodontia Flashcards
The knowledge of anatomical structures is crucial to?
perform surgery that respects the integrity of the anatomical findings
Surgical anatomy is?
The study of the structure and morphological characteristics of the tissues and organs of the body as they relate to surgery
Topographic anatomy is:
the study of anatomy based on regions or divisions of the body and emphasising the relations between various structures (muscles and nerves and arteries etc.) in that region
The surgical anatomy structures are
8:
Teeth and surrounding structures
Mandible
Floor of the cavity
Tongue
Maxilla
Palate
Cheek
Lips
The surrounding structures of teeth are:
- cementum
- PDL
- alveolar bone
- gingiva
Teeth are made up of:
- crown
- cervical line
- root
The clinical crown vs anatomical crown:
- clinical crown is the portion of the tooth that is above the gingival margin
- anatomical crown is the part of the tooth that is covered with enamel
Cervical line is?
DEJ
Which of the jaw bones is less dense?
Maxilla
Surgical considerations regarding teeth and their surrounding structures:
- Anaesthetic technique
- Tooth position/access
- Tooth anatomy
- Surgical instruments
- Complications
Cementum is
Bone like tissues which covers the dental roots
- avascular and lacks nerves
- perforated by sharpeys fibers
- overlaps enamel
PDL ?
- function
- composition
- connects what to what
- nerves and blood supply?
- support the teeth and provide sensory information
- Dense fibrous connective tissue (0.2mm wide)
- Connect the alveolar bone and cementum
- Rich nerve and blood supply
Alveolar bone:
- function
- dependent on?
- composed of?
- how does it look like on an xray
• Supports and protects the teeth.
• Dependent on the presence of teeth and functional stimuli.
• Septa/ interradicular septa.
• X-rays: continuous dense white line about 0.5-1mm thick (LD).
Gingiva:
- composition
- location
- 3 types of gingiva
• Fibrous tissue covered with a smooth vascular mucous membrane.
• Envelope the alveolar process of the jaws and the neck of the teeth. At the neck of the teeth becomes continuous with the periodontal ligament.
• Free gingiva, attached gingiva, and interdental gingiva
3 types of gingiva:
• Free gingiva: collar around teeth.
• Attached gingiva: attached to the alveolar process.
• Interdental gingiva: between teeth.
The mandible is made up of ?
Anterior and posterior mandible
The anterior mandible is
Between the 2 mental foramen
Anterior mandible:
• Bone level:
• Buccal surface:
• Lingual surface:
• Inferior border:
• Bone level: incisive nerve/vessels. (Teeth)
• Buccal surface: mental neuro vascular bundle. • Lingual surface: genioglossus muscle (attaches to the genial tubercle)
• Inferior border: submental artery
Posterior mandible:
• Bone level:
• Buccal surface:
• Lingual surface:
• Bone level:
1. Inferior alveolar nerve.
2. Inferior alveolar artery.
3. Inferior alveolar vein.
• Buccal surface:
1. Facial artery.
2. Buccal nerve.
• Lingual surface:
1. Lingual nerve.
2. Mylohyoid muscle.
Floor of the mouth:
- location
- made up of
- muscles there
- structures present
- Small region situated beneath the mobile part of the tongue and above the mylohoid muscles.
- Sublingual papilla (submandibular salivary duct ) + Sublingual folds.
- Mylohyoid + geniohyoid.
- Ranine artery, Wharton duct, ducts of Rivinus, Duct of Batholin, Lingual nerve, Sublingual artery
Which duct is the largest, and joins the submandibular duct.
Duct of Batholin
Tongue:
- definition
- portions
- attachments
- 2 planes
- Highly muscular organ of deglutition, taste, and speech.
- 2 portions: oral and pharyngeal.
- Attached to the hyoid bone, mandible, styloid processes, soft palate, and the pharyngeal wall.
- Mucosal plane and muscular plane
Mucosal plane:
- covered by
- shape
- Covered by numerous papilla. Taste buds.
- V shaped sulcus terminalis:
Anterior, oral, presulcal.
Posterior, pharyngeal, postsulcal.
Muscular plane:
Extrinsic: genioglossus, hypoglossus, styloglossus, chondroglossus, and palatoglossus.
Lingual artery, dorsal lingual arteries, sublingual artery, and deep lingual artery.
Maxilla:
- posterior area
- anterior area
Posterior: posterior to canine
Anterior: between canines, Inter canine portion
Anterior area:
- bone level:
- external surface:
- bone level:
1. Incisive canal
2. Nasopalatine neuro vascular bundle
3. floor of the nasal fossa - external surface: Infraorbital neuro vascular bundle
Posterior area:
- bone level:
- external surface:
- bone level:
1. Maxillary sinus
2. PSA artery (posterior superior alveolar artery) - external surface:
1. Stenson duct
2. Buccal fat pad (Bichat): between masseter and buccinator
3. Pterygopalatine fossa
4. Maxillar nerve
5. Maxillar artery
6. Pterygoid venous plexus
Palate:
2 parts:
- hard and soft
Hard plate:
- formed by?
- covered by?
- lateral regions
- Formed by the palatine process of the maxillae and the horizontal plates of the palatine bones
- Covered by a thick mucosa bound tightly to the underlying periosteum
- Lateral regions: neuro vascular bundle.
Soft palate:
- definition
- includes
- inferior border:
- Mobile flap suspended from the posterior border of the hard palate
- Thick fold of mucosa enclosing an aponeurosis, muscular tissue, vessels, nerves, lymphoid tissue, and mucous glands
- Inferior border: conical process, the uvula, projects downwards
Innervation of the palate:
• Nasopalatine neuro vascular bundle (hard)
• Greater palatine neuro vascular bundle (soft)
Cheek:
- outer surface:
- inner surface:
- structures present
- Outer surface: skin.
- Inner surface: mucosa.
- Buccinator muscle, buccal fat pad, fibrous connective tissue, vessels, nerves, numerous small buccal mucous glands.
- Buccal fat pad , Stenson duct, Facial artery, Facial nerve
Lips:
- definition
- muscle
- vascualraisation
- submucosa
- nerves
- Two fleshy folds surrounding the oral orifice
-Orbicularis oris
- Well vascularised
- Submucosa: minor salivary glands
- Superior labial artery and Inferior labial artery
