Third molars

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Third molars

• 3-7-08

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Maxillary Molars Sinus Proximity Alternate
Procedure

• Palatal root sitting close to the sinus
• Reflect a flap
• Stryker bone off the buccal
• Separate the buccal roots from the crown
• Remove the palatal root with the crown
• Remove the buccal roots individually

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Review again
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Mandibular Molars

• Divide the tooth buccolingually from the buccal
  furcation towards the lingual with a Stryker
• ONLY go 2/3 of the way to the lingual plate
• Use elevator to split remaining tooth structure
• WRITE IT DOWN in Post-op Notes
• Remove the root with less interference
• Remove the mesial root if it has less curvature
• Remove the interseptal bone to free the distal
  root

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Geriatric Patients

• Bone characteristics
• Dense
• Inelastic
• Roots tend to break more easily
• Prepare to surgically remove the tooth

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Malposed teeth

• Mandibular premolars-displaced to the lingual
  very difficult
• Procedure
• Reflect a flap
• Make a window in the plate
• Tap the tooth to the lingual
• The lingual plate should break
• Remove tooth
• Should the buccal plate come out, dont put it
  back

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Wisdom Teeth

• Reasons to keep the 3rds
• The patient can maintain cleanliness
• It actually functions in occlusion
• There is adequate attached gingiva

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Wisdom Teeth

• Asymptomatic wisdom teeth become problematic in
  the future
• Get them out when they are younger
• Lesser complications-less recovery time
• Remove when 1/3 of the root is formed
• One anesthesia risk, one surgery, one swelling,
  one pain

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Asymptomatic vs. Symptomatic

• Symptomatic- no brainer, git em oudda der
• Pericoronitis
• Periodontitis
• Pathologic Resorption
• Neoplasms
• Orthodontic Treatment
• Pre-Dentures
• Pain
• Caries

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Pericoronitis

• You must have a portion of the crown in the oral
  cavity to actually call it pericoronitis
• Impacted teeth are impacted, duh
• Patients with pericoronitis at time of extraction
  have higher potential for dry socket (loss of
  blood clot, causing excruciating pain post-op)

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Pericoronitis

• If you do an operculectomy and dont remove the
  tooth, it will grow back
• (not the tooth)
• Just get the tooth out

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Pericoronitis

• Best treatment for full infection of 3rd
  molars-ID tooth, place patient on antibiotics,
  let things calm down and take all four 3rd molars
  out at one time
• If try to extract 3rd molars will have anesthesia
  problems while the patient is still infected in
  the acidic environment

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Periodontitis

• Potential periodontal problem
• Left alone, the third molar becomes decayed
• The decay undermines the second molar creating a
  periodontal problem
• Decay may extend to the second molar, reaching
  the pulp
• You lose both the third and the second molar
  (Its a lose, lose, lose situation)

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Periodontitis
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Pathologic Resorption

• The erupting third molar may resorb the second
  molar roots and surrounding bone

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Neoplasms

• Dentigerous cyst
• Keratocyst
• Ameloblastoma
• The most common cyst is the dentigerous cyst

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Dentigerous Cysts

• Dentigerous cyst-associated with the crown of an
  impacted 3rd molar
• 3rd molars left in the mouth, epithelial lining
  in cyst can transform with time
• The epithelium can turn into squamous cell
  carcinoma, mucoepidermoid carcinoma, cyst can
  also get larger and larger
• Pathologic fracture because the whole ramus is
  full with dentigerous cyst that has grown over
  time
• Ameloblastoma, keratocysts-other neoplasms
  associated with the 3rd molar area and associated
  with the cyst/sac

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Orthodontic Treatment

• Most of the time, the arch is not large enough to
  accommodate third molars (i.e. we who are born
  without thirds are more evolved than those with
  thirds.)
• Orthodontic treatment-3rd molar resorbs 2nd molar
• Refer patients either before or after orthodontic
  treatment because hard to make flap, preferably
  before
• Do not refer orthodontic patients during
  treatment because the wires and hooks make it
  difficult to make a flap

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Pre-Denture

• Edentulous ridge,-nothing more embarrassing then
  making a denture for a patient 6 months later
  denture doesnt fit because patient is growing
  new teeth in mouth
• Missed the impacted 3rd molars-all teeth removed
  in mouth, but pano wasnt taken to determine if
  there were impacted 3rd molars
• If impacted 3rd molars close to the surface, with
  pressure/rubbing of the denture, the little bit
  of bone that was over tooth is gone impacted
  3rd molar may erupt into mouth

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Pain, Caries

• Self-explanatory

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Jaw Fractures
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Most common sites
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Jaw Fractures

• Fractured mandible-most common places for 3rd
  molars to fracture, 3rd molar sitting in the
  angle, acts as a weak link undermines angular
  amount of bone

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Lock Key

• 3rd molar can act as lock key, may keep the two
  pieces of jaw fractures together if have fracture
  through the crypt of the 3rd molar
• Because of the way the 3rd molar sits, it keeps
  two pieces of jaw fractures from pulling apart
  and separating
• Leave 3rd molar in place as fracture heals
• Problem with this type of fracture-bacteria can
  get into the fracture and around the tooth itself
  
• Tooth can become necrotic, then get a non-union
  because infection is in the line of fracture
• Periodically watch the tooth for necrosis

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Reliable Patients

• On a reliable patient with a jaw fracture
• 3rd molar is acting as a lock key and keep the
  pieces from moving apart
• Then can leave tooth in the line of fracture
• Get the patient back in and xray every week or
  every other week, patient kept on antibiotics and
  watch for tooth necrosis

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Non-reliable Patients

• Highland-patients not reliable and do not come
  back for post-op do not leave any tooth in the
  line of fracture at highland because tooth can
  become infected, then get a nonunion/malunion
  which creates a big problem
• If extract that 3rd molar, then disrupt that lock
  key end up with two pieces in different areas
• Need to take patient to the operating room, make
  an incision underneath the mandible, bring pieces
  back and wire it together because lost the 3rd
  molar that was acting as the lock key
• If jaw fracture is open to the oral environment,
  prescribe antibiotics, if mucosa is intact and
  not exposed to oral environment, no need to
  prescribe antibiotics

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