LOCAL ANAESTHESIA:ANATOMICAL LANDMARKS

SEMINAR 1DR.LEENA PARMAR

CONTENTS:

1. INTRODUCTION2. TRIGEMINAL NERVE a.Ophthalmic division b.Maxillary division c.Mandibular division3.Osteology of maxilla and mandible4.Anatomical landmarks in various

injection techniques

INTRODUCTION

Understanding 0f the management of pain in dentistry requires thorough knowledge of nerves and bones a dentist has to deal with.

Mainly the Trigeminal nerve and its three divisions , maxilla and mandible.

TRIGEMINAL NERVE

Largest cranial nerve Ganglion associated with trigeminal

nerve is semi-lunar or gasserian ganglion which is located in Meckle’s cavity of temporal bone.

Functions- MotorSensory-general & gustatory

Petrous part of temporal bone

Motor root : supplies the following muscles

1. Masticatory-masseter,temporalis,pterygoideus medialis and pterygoideus lateralis

2. Mylohyoid3. Anterior belly of digastric muscle4. Tensor tympani5. Tensor veli palatini

Sensory Root

Comprises the central part of semilunar ganglion.

3 divisions- o Ophthalmic division(v1)o Maxillary division(v2)o Mandibular division(v3)

Ophthalmic Division

Smallest of three divisions Exclusively sensory Leaves cranium from superior orbital fissure Supplies-eyeballs,conjunctiva,lacrimal gland, Parts of mucous membrane of nose and para-

nasal sinus,skin of forehead,eyelids and nose. 3 divisions- Nasociliary nerve Frontal nerve Lacrimal nerve

Maxillary Nerve Leaves cranium from foramen

rotundum

1.Branches in cranium-middle meningeal nerve

2.Branches in pterygo-palatine fossa;a) Zygomatic nerve-

Zygomatico-temporal nerve Zygomatico-facial nerve

b.Pterygopalatine nerves-Orbital branchesNasal branch and naso-palatine

nervePalatine branchGreater(anterior palatine nerve i,.lesser(middle or

posterior )palatine nerve ii.pharyngeal branchesc)Posterior superior alveolar nerve

3.branches within the infra orbital canal

a)middle superior alveolar nerve b)anterior superior alveolar nerve4.Branches on face a)inferior palpebral branch b)external nasal branch c)superior labial branch

Maxillary Nerve innervates;

1.Skin-a) Middle portion of faceb) Lower eyelidc) Side of the nosed) Upper lip

2.Mucous membrane- e) Naso-pharynxf) Maxillary sinusg) Soft palateh) Tonsili) Hard palate

3.Maxillary teeth and periodontal tissues

NOTE-NASOPALATINE NERVE

Terminal branch enters incisive canal and

comes out from incisive foramen

Provides sensation to palatal mucosa in the reason of pre maxilla(Central incisors,lateral incisors and canines)

Present 1 cm posterior to maxillary central incisor

Mandibular Nerve

Largest division

Leaves the cranium from foramen ovale

Has large sensory root and small motor root

Branches of Mandibular nerve

1. Branches from the undivided nerve- a)nervous spinosus

b)nerve to medial pterygoid

muscle

2.Branches from anterior division a) Nerve to lateral pterygoidb) Nerve to the masseter c) Nerve to the temporalisd) Buccal nerve

3.branches from the posterior division a)aurico-temporal nerve b)lingual nerve c)mylohyoid nerve d)inferior alveolar nerve e)mental branch f)incisive branch

.

Nerve innervation around condylar process of mandible

Special note 1: buccal nerve Also known as long buccal

nerve/buccinator nerve

Emerges under the anterior border of masseter muscle

Provides sensory innervation to 3rd ,2nd & 1st mandibular molar,mucobuccal fold of this region,sensory innervation to cheek

Special note 2:lingual nerve Runs parallel to inferior alveolar

nerve(medially) and also medial to submandibular salivary gland duct

Provides sensory innervation to anterior 2/3 of tongue(normal sensory and special sensory along with chorda-tympani fibers),mucous membrane of floor of the mouth and gingiva of the lingual side of mandible

Special note 3:inferior alveolar nerve

It runs parallel and lateral to lingual nerve on the medial surface of the mandible

Enters mandible at mandibular canal level

Emerges from the mental foramen

Gives off dental branch-incisive branches

MAXILLA

Anterior view of maxilla

SENSORY INNERVATION OF PALATE

MANDIBLE

Lateral view of mandible

Posterior view of mandible

REFERENCES

1. Handbook of LOCAL ANAESTHESIA-Stanley F Malamed

2. Atlas of anatomy-Anne M Gilroy3. GRANT’S atlas of anatomy-Anne

M.R.A agur & Arthur F Dalley

Summary of maxillary injection

Supra peri-osteal injection

Posterior-superior alveolar nerve

Middle-superior alveolar nerve

Anterior superior alveolar nerve

Infra-orbital(IO) nerve

Greater palatine(GP) nerve block

Nasopaltine(NP) nerve block

anterior middle superior alveolar(AMSA) nerve block

summary of mandibular injections

Inferior Alveolar Nerve Block

Buccal Nerve Block

Mental Nerve Block

Incisive Nerve Block

Gow-Gates Mandibular block

Periodontal Ligament Injection