INFERIOR ALVEOLAR NERVE BLOCK

 INFERIOR ALVEOLAR NERVE BLOCK


*  Anatomical Landmarks of Inferior alveolar

    nerve block:


     • Mucobuccal fold
     • Anterior border of Mandibular ramus
     • External oblique ridge
     • Internal oblique ridge
     • Retromolar triangle
     • Pterygomandibular ligament
     • Buccal sucking pad

     • Pterygomandibular space


* Nerves Anesthetized by Inferior alveolar  

   nerve block:


   • Inferior Alveolar Nerve and its Sub-

     divisions :

                Mental Nerve
                Incisive Nerve
                Lingual Nerve

                Buccinator Nerve


* Areas Anesthetized by Inferior alveolar  

   nerve    block:


   • Body of Mandible and an inferior portion of       the ramus

   • Mandibular teeth: Incisors, Canine,

     Premolars and Molars

   • Mucous membrane and underlying tissues

     anterior to the first mandibular molar    

     (supplied by Lingual nerve)

                                    


* Note: To anesthetize the soft tissue  

              posterior to the 1st molar Long Buccal

              nerve should be anesthetized.


* Amount of LA injected :-  1.8 ml


* Injection Technique used for Inferior  

   Alveolar Nerve Block (Patient Left Side):-

    • The Patient is seated comfortably on  

      the Dental chair and the dentist stands on

      the right side of the patient partially facing

      the patient. For the Left side IANB the    

      Dentist stands more to the Front of the

      patient. (These are for a Right Handed  

      Dentist)


   • The Head of the patient is placed such that

      the Body of  Mandible is parallel to the    

      floor.


   • The Dentist / Operator uses his/her left

      index finger or Thumb to palpate the

      Mucobuccal fold. If thumb is used the    

      index finger can be placed on extra orally

      behind the ramus thus holding the

      mandible between your thumb and index

      finger to assess the width of the Ramus.


   • The finger is then moved posterior to

      contact the External oblique ridge on the

      anterior border of the Ramus of mandible.


   • From here it is moved up or Down in

     search of the greatest depression called

     the Coronoid Notch which is in direct line

     with the Mandibular sulcus.


  • The palpating finger is moved lingually

    across the retromolar triangle and onto the

    internal oblique ridge.


 • The finger which is on the coronoid notch

   and in contact with the internal oblique ridge

   is moved to the buccal side to move the

   Buccal Sucking pad away the path of

   insertion.


 • This gives better exposure to the internal

    oblique ridge, the pterygomandibular

    raphae and the pterygomandibular

    depression.


 •  The Needle is inserted parallel to the

    occlusal plane of the mandibular teeth from

    the opposite side (Approximately over

    opposite side Premolar) of the mouth at a

    level bisecting the finger or thumbnail

    penetrating the tissues of the  

    pterygotemporal depression, and entering

    the pterygomandibular space.


 • The needle is penetrated until bone is

   contacted on the internal surface of the

   ramus of the mandible.


 • After contacting bone the needle is

   withdrawn about 1mm and then 1 to 2 ml of

   solution is deposited slowly over a duration

   of 2 minutes into the tissue.


* Technique for anesthetizing lingual nerve :


  • Needle is withdrown about half of its length

    which was inserted and local anesthetic

    Solution is injected at the area which  

    anesthetized lingual nerve.


* The signs and symptoms of an inferior alveolar block

   are:


 •  Tingling and numbness of the lower lip (however it is not  

    an  indication of depth of anesthesia).

Tingling and numbness of the tongue (see Lingual Nerve Block). No pain is felt during dental treatment.