Local Anesthesia

Local AnesthesiaJ

Local anesthesia ni kalau nak mudah faham ia berkaitan dengan bius.Kalau ktorg nak senang panggil LA je..hee.. Bius setempat. Ada banyak jenis LA ni. Antaranya surface anesthesia, Infiltration anesthesia dan regional block anesthesia.

Ni yang main type punya. Jadi kita go through satu2..

Surface anesthesia

Nama lain kita panggil topical anesthesia..sebab dia berkaitan kulit kan..

Ada banyak form, mcm: ointments, gelly,spray dan cream

Most common ointment: EMLA (2.5%: lidocaine, 2.5%: prilocaine =5%)

 Gelly banyak flavor and selalu guna utk intraorally (dalam mulut) dan untuk budak2..

LA spray: 10%

Ethyl chloride spray: produce surface anesthesia by cooling.

Infiltration anesthesia.

Yang ni banyak..tapi cara aku ingat macam ni..conventional injection technique

Periosteal ada 3: supra, para and sub

Intra ada 2: osseous and ligamental

Submucosal

Yang paling common: supra periosteal.

Regional block anesthesia

Conduction anesthesia

Nak bius orang bukan senang.kena tahu technique. Salah technique je boleh menyebabkan patient merana seumur hidup..naudzubillah.

Dan ni antara yang biasa @ conventional injection technique.

LA technique:

Target: small nerve ending. (flooded with LA solution)

Selalu guna: maxillary teeth and mandibular incisors(lower anterior)

Nerve block technique: conduction technique

Target: main trunk

So bila dah block main trunk..maka nye terblock la jugak

v  Nasopalatine nerve

v  Greater palatine nerve

v  Lesser palatine nerve

v  Buccal nerve

v  Lingual nerve(mandible)

v  Buccal nerve

Kenapa guna block anesthesia dekat mandible and infiltration dekat maxilla?

Ø  Sebab anesthesia solution tak boleh penetrate masuk ke compact vestibular bone in the mandible jd LA tak successful..

Ø  Mandible: thick cortical plates..and infiltration tak kan penetrate cortex to reach the apices of teeth.

Ø  Maxilla: tulang dia soft and thin( spongy) bone jadi infiltration sufficient je

Disadvantage block anesthesia.

·         Increased risk of trauma of nerve trunk.

·         Accidental intravascular injection in of LA solution.

Ada technique lain juga..(other technique)

1)Periodontal Ligament, PDL technique

Selalu guna: mandibular molars (alternative pada nerve block technique)mungkin sbb ID block tak working so bagi je la technique ni.

Technique ni simple je; hanya inject LA solution within periodontal ligament space. Perlu small amount (0.2ml)  sbb PDL ni kecik je.

Letak needle dkt gingical sulcus and advances along the root surface until resistance is met. Masa inject tu patient akan rasa slight pressure because it is very small space.

Injection ni  tak sakit and anesthethic effect dia hnaya pada pulp and desmodontal nerve

Duration: 10-15 minutes

PDL injection ni sesuai utk extremely anxious patients and children

2) Intrapulpal injection.

Guna injection ni bila block and infiltration tak  berkesan

Small quantity (0.1ml)

Duration: 10 minutes

Fast and sakit sikit masa mula2 introduce injection.

3) Intraosseous injection.

Force the needle in cortical plate and cancellous bone

Guna injection ni kalau block ansthesia pun tak berkesan pada mandible. Sesuai guna untuk mandible sebab perforate the cortex then introduce wthin the bone.

Mcm mana perforate the cortex?

·         Guna hand-piece with a very fine bur. There is small piece will guide the hanpiece where to drill, then the needle will go through the same piece to get the anesthesia inside the bone.

4) Jet injection( non-needle, needle-less dentistry)

Very recent technique

Principle jet instrument: small quantities of liquids forced through very small opening under high pressure can penetrate mucus membrane or skin without causing tissue trauma.

Good utk surface anesthesia

One jet injection : hold 1.8 ml cartridge of LA, it can be adjusted to expel (0.05-0.2 ml solution under 2000 psi pressure.