ID Block

• Describe Block Anaesthesia: Dental nerve before it enters the mandibular foramen. Whole distal distribution of nerve is anaesthetised. Takes longer to build up but also lasts longer than infiltration anaesthesia. Solution is deposited at the nerve trunk of the inferior.
• Indications of an ID Block:

  Quadrant lower arch scaling, restorations of mandibular teeth distal to lower first premolar. extraction of primary molar teeth.
• How would we treatment plan when using an ID Block?

  Introduce LA on upper teeth first if possible, gain pt confidence, as blocks can be more uncomfortable to give and have a higher failure rate.
• What nerves are we anaesthetising with an id block?

  The inferior dental nerve (3rd division of trigeminal), pulpal innervation of all teeth to midline, lingual nerve: lingual gingivae and anterior 2/3 of tongue, and long buccal: buccal gingivae from 3rd molar to 1st molar.
• How many patient require re-injection for an ID block?

  1 in 5
• Where must solution be deposited during a block?

  1mm of the target nerve
• Why is accuracy more difficult with an ID block than a LIA?

  Greater penetration of tissue by the needle required.
• What is the success rate of an ID Block?

  80%
• What ID block technique do we do as students?

  Direct technique
• Why do we not do bilateral blocks?

  extreme discomfort, difficulty swallowing, difficulty with speech, asphyxiation
• What are contraindications of ID Blocks?

  Infection at site of injection, pt may bite lip or tongue, pt who can't co-operate or sit still, clotting defects, only on warfarinised pt if INR is 3.5 or below
• What nerves are anaesthetised during an ID block?

  • inferior dental nerve
  • incisive nerve
  • lingual nerve
  • mental nerve
• What are the areas anaesthetised by an ID Block?

  Mandibular teeth to midline, body of mandible, buccal gingivae anterior to 1st molar, lingual soft tissues and periosteam and anterior 2/3 of tongue and floor of mouth.
• What nerve requires a separate injections?

  long buccal nerve
• What equipment is required for an ID block?

  Aspirating syringe, 27 gauge needle 35mm long, anaesthetic cartrige
• Where are we targeting during an ID block?

  ID nerve as it passes down towards mandibular foramen before it enter bone of the mandible
• Describe the positioning for an ID block?

  For right id block and a right handed operator, sit/stand at 8 o'clock and face the patient, for left id block sit at 10 o'clock behind the patient. Patient should be semi-supine or supine and mouth wide.
• What landmarks do we consider when giving an ID Block?

  Coronoid notch, to identify with thumb/finger, pterygomandibular raphe, occlusal plane of mandibular posterior teeth - aim for 1cm above this plane, depth: contact bone 20-25mm, 2/3 or 3/4 of the long needle
• What percentage of positive aspiration occurs during ID block?

  10-15% highest of all intra oral injection techniques
• After an ID block, describe how to administer lingual anaesthetic?

  Slowly withdraw syringe, a short distance when ¾ of cartridge remains - re-aspirate, Deposit 0.1ml of solution for anaesthesia of the lingual nerve, withdraw syringe completely from tissues, Wait 3 - 5 minutes before commencing procedure.
• How do we know if an ID block is successful?

  • tingling then numbness of lower lip
  • tingling then numbness of tongue
• Where is the target for the long buccal injection?

  buccal nerve as it passes over anterior border of ramus
• What are the landmarks for a long buccal injection?

  Mandibular molars, mucobuccal fold, needle into peristeum 1-2mm,
• Why might an ID block fail?

  low deposition of anaesthetic (so would re inject higher site), depositions too far anteriorly, insufficient solution injected, no bone contact due to over insertion, DO NOT DEPOSIT SOLUTION IF BONE NOT CONTACTED, as needle tip might cause facial paralysis as parotid gland perforated.
• How would you manage transient facial paralysis?

  Explain to patient, protect the eye, should wear off after 20-40mins, LA will not work
• What are some signs of Transient facial paralysis?

  LA in parotid gland, drooping of eyelid and corner of mouth, inability to blink/smile
• Haematoma

  Swelling of tissues on medial side of ramus, apply pressure and cold for minimum of 2 minutes, avoid aspiration, careful technique and avoid blocks with patient on anticoagulated medication.
• Trismus?

  Muscle soreness/ limited movement of medial pterygoid due to needle trauma or infection in infratemporal fossa, if mild take analgesics or heat therapy and should reduce after 24 hrs, if sever seek dentists advice.
• Lip and Cheek Biting

  Soft tissues anaesthesia lasts longer than pulpal, so self inflict trauma can occur, warn patient against eating/drinking hot things, don't use IDB on uncooperative patient, advice on cigarette smoking.
• Broken needle?

  Causes: smaller needles (30g) more likely to break, previously bent needles, defective manufacture, forcible contacting bone - pt may unexpectedly move, try to remove with tweezers, if lost inform dentist/patient and record and refer to oral surgery.
• Stop before you block?

  Avoid giving block on wrong side, all blocks must be supervised by qualified member of staff, review notes and procedure, confirm correct side
• What is the maximum does of LA for a 70kg adult?


  7 Cartridges