MANDIBULAR INJECTION TECHNIQUES

- successful: full primary dentition

- unsuccessful: mixed dentition (due to thickened cortical plate)

when is a mandibular infiltration known to be successful or unsuccessful?

1. anatomic variation in the height of the mandibular foramen and bone density

2. greater depth of penetration leading to greater inaccuracy

what are the 2 factors that contribute to the lower success rate of IAN block?

incisive nerve block

a valuable alternative to IAN block when tx is limited to teeth anterior to the mental foramen (incisors to 2nd PM)

Gow-gates mandibular never block

a true mandibular block injection which provides regional anesthesia to all sensory branches of v3

1. problems with anatomic variations in the height of mandibular foramen are obviated

2. anesthesia of sensory branches (lingual. buccal and mylohyoid) + IAN are attained

what are the 2 benefits or advantages of Gow-gates block?

95%

what is the success rate of Gow-gates MN block given that there is proper adherence to protocol and experience?

Closed-mouth mandibular nerve block

it allows the doctor to achieve clinically adequate anesthesia in an extremely difficult situation

trauma, infection, postinjection trismus

what are the 3 instances wherein Vazirani-Akinosi technique can be used?

Vazirani-Akinosi technique

Closed-mouth mandibular nerve block is also known as?

IAN block

the 2nd most frequently used (after infiltration) and possibly the most important injection technique used in dentistry

IAN block

the most frustrating, with the highest percentage of clinical failures even when properly administered

PDL injection

this injection might be necessary when isolated MN teeth remain sensitive after an otherwise successful IANB

intraosseous anesthesia

a supplemental technique employed, usually on molars, when the IANB has proven ineffective, primarily when the tooth is pulpally involved

- px feels unable to swallow

- px can self-injure

what are the complications of IAN block knowing that it also

entire right or left side

which is more preferred, treating an emtire right or left side of a px oral cavity at one appointment or bilateral IANB?

MILI

- mental

- incisive

- lingual

- inferior alveolar

enumerate nerves anesthetized by the IAN block

1. man. teeth to the midline

2. body of the MN, inf. portion of ramus

3. buccal mucoperiosteum, mucous membrane ant. to mental foramen (mental n.)

4. ant. 2/3 if the tongue and floor of the oral cavity (lingual n.)

5. lingual soft tissues and periosteum (lingual n.)

enumerate the areas anesthetized by IAN block

- procedures on multiple MN teeth in 1 quadrant

- when buccal soft tissue anesthesia (ant. to mental foramen) is necessary

- lingual soft tissue anesthesia

what are the 3 indications for an IANB?

- infection or acute inflammation in site

- px to bite their lip or tongue (young child or physically/mentally handicapped)

what are the 2 contraindications for IANB?

wide area of anesthesia for quadrant dentistry

an advantage of IANB

- wide area, not for localized procedures

- 31-81% rate of inadequate anesthesia

- inconsistent intraoral landmarks

- 10-15% positive aspiration (highest of all)

- uncomfortable and dangerous lingual and lower lip anesthesia (self-infliction)

- partial anesthesia for bifid IAN and bifid MN canals

what are the 6 disadvantages of IANB?

mental nerve block

it is used for buccal soft tissue anesthesia ant. to the 1st molar

incisive nerve block

it is used for pulpal and buccal soft tissue anesthesia of teeth ant. to the mental foramen

25-gauge long

recommended needle for IANB

mucous membrane on the medial (lingual) side of the ramus

what is the area of insertion for IANB?

- coronoid notch

- pterygomandibular raphe

- occlusal plane of the MN posterior teeth

what are the landmarks of IANB?

because the needle approaches the IAN at roughly a right angle

why is orientation of the needle bevel of IANB less critical than other nerve blocks?

- right: 8 o'clock

- left: 10 o'clock

what are the correct positions of a right-handed operator administrating a left and right IANB?

supine (better) or semisypine

what is the patient position during an IANB?

1. height of injection

2. anteroposterior site of injection

3. penetration depth (bone should be contacted)

what 3 parameters must be considered during an IANB?

2/3 - 3/4 of a long needle (20-25 mm)

what is the needle depth of penetration of IANB?

corner of the mouth (premolars)

when administrating an IANB, where should the syringe barrel be placed at?

needle tip can rest within the parotid gland causing paralysis of the facial nerve

what happens if you overinsert and deposit LA despite bone not being in contact?

1. deposition of the anesthetic is too low

2. deposition of the anesthetic too far anteriorly on the ramus

3. accessory innervation to the mandibular teeth

4. incomplete anesthesia of the central or lateral incisors

what are the 4 most common causes of absent or incomplete IANB?

long buccal n. block, buccinator n. block

what are the 2 other names of buccal nerve block?

accessible buccal nerve as it lies beneath the mucous membrane (not buried within the bone)

why does the buccal nerve block success rate approach 100%?

- CI: infection or acute inflammation

- adv: high success rate and easy

- disadv: potential fir pain when periosteum is contacted

what are the contraindication, advantages and disadvanatages of a buccal nerve block?

0.7%

what is the positive aspiration rate of buccal n. block?

MILIBAM

- mylohyoid, IAN, lingual, incisive, buccal, auriculotemporal, mental

what are the nerves anesthetized in Gow-gates technique?

- IO: mesiopalatal cusp of the MX 2nd molar

- EO: lower border of tragus, corner of the mouth

what are the intraoral and extraoral landmarks of Gow-gates technique?

hematoma, trismus, paralysis of CN III, IV, VI (diplopia, blepharoptosis, complete paralysis of right eye)

what are the complications of the Gow-gates technique?

too little solution, anatomic difficulty

what are the 2 causes of a failed Gow-gates?

Akinosi technique, Closed-mouth MN nerve block, tuberosity technique

what are the 3 other names for Vazirani-Akinosi technique?

MILIM

- mylohyoid, IAN, lingual, incisive, mental

what are the nerves anesthetized in Vazirani-Akinosi technique?

- mucogingival junction of the MX third (or 2nd) molar

- MX tuberosity

- coronoid notch on ramus

what are the landmarks of Vazirani-Akinosi technique?

25 mm

what is the depth of insertion of Vazirani-Akinosi technique?

motor nerve

which nerve (motor or sensory) is faster in acquiring paralysis during Vazirani-Akinosi technique?

- flared ramus

- too low needle insertion point

what are the 2 causes of a failed Vazirani-Akinosi technique?

hematoma (<10%), trismus (rare), transient facial nerve (VII) paralysis

what are the possible complications of Vazirani-Akinosi technique?

mucobuccal fold, MN premolars, mental foramen

what are the landmarks of the mental nerve block?

5-6 mm

what is the depth of insertion for mental nerve block?

mental n., incisive n.

what are the nerves anesthetized during incisive nerve block?

incisive nerve block has a finger pressure over the mental foramen to direct the solution

what is the difference between incisive nerve block and mental nerve block?

peridental injection (orig)

intraligamentary injection

what are the other names for PDL injection?

0.2 mL per root min. of 20 seconds

what is the anesthetic volume in PDL injection?

- frontal: 45 degrees to the long axis of the tooth

- sagittal: right angle to the soft tissue

what is the needle orientation in frontal and sagittal plane during intraseptal injection?

0.2-0.3 mL

what is the anesthetic volume for a intrapulpal injection?

intrapulpal injection

the only injection technique that provides pressure anesthesia