Wednesday, 27 February 2013

Alveolar osteitis (dry socket)

Definition: A recently extracted tooth that has been filled initially with a clot, that disintegrated, leaving the socket of bone partially/ completely bare.

Signs and symptoms:
  • Moderate to severe pain (localised to the socket),
  • foul odour or taste (without suppuration),
  • symptoms occuring 3 – 5 days post-exo,
  • absence of swelling/ lymphadenopathy/ bacteraemia,
  • course of pain can last 10 – 40 days
Possible causes:
  • Excessive mechanical trauma during exo,
  • inadequate blood supply to extraction site,
  • pre-existing infection,
  • vasoconstriction effects secondary to LA (especially intraligamental) or to diabetes,
  • loss of blood clot due to mechanical factors,
  • diseased tissue/ foreign bodies remaining in socket,
  • patient's age,
  • smoking, use of oral contraceptives,
  • trauma and inadequate irrigation of extraction site,
  • use of steroids,
  • poor OH and periodontal conditions,
  • pericoronitis
Management: 
  • Confirm radiographically no retained roots/ foreign bodies.
  • Under LA, socket gently irrigated with warm saline to clear out necrotic debris (socket should NOT be curetted to bare bone, because that would expose more bone and increase pain)
  • Socket dried of excess saline.
  • Dressing placed into socket —iodoform gauze / Gelfoam soaked in eugenol should be inserted loosely to cover the wall of the socket.
  • Dressing is changed every 24 hours for the first 2 – 3 days; dressing is changed every 2-3 days thereafter till granulation tissue covers bone.
  • Prescribe analgesics, NSAIDs. Antibiotics rarely indicated.

LAop: Surgical procedure

 
1.    Reflect adequate mucoperiosteal flaps for accessibility
>       Difficulty of removing an impacted tooth depends on accessibility
>       Reflection of flap must allow placement & stabilization of retractors and instruments for bone removal, and soft tissue retraction without damaging the flap
>       Envelope flap
                       i.     Quicker to close, heals better than 3-cornered flap
                      ii.     How?
Mandbular: Mesial papilla of 6, around necks of teeth, to db line angle of 7,
posteriorly to and laterally up anterior border of mandibular ramus.
Maxillary: Posteriorly over tuberosity from distal of 7,  anteriorly to mesial of 6
                     iii.     Carefully palpate retromolar area before beginning incision.
Incision extends laterally posteriorly as mandible diverges laterally. Straight extension of incision will fall off the bone and into sublingual space, may damage lingual nerve.
                    iv.     Flap reflected laterally to expose external oblique ridge with periosteal elevator.
                     v.     Surgeon should not reflect more than a few mm beyond EOR as this results in increased morbidity and complications.
                    vi.     Retractor (Austin, Minnesota) placed on buccal shelf, lateral to EOR, stabilized by applying pressure towards bone.
>       3-cornered flap: Envelope flap with releasing incision
                       i.     Allows greater access to more apical areas of tooth without risk of tearing
                      ii.     Flap must have a broad base
>       Incision principles
                       i.     Smooth stroke of scalpel
                      ii.     Keep in contact with bone throughout entire incision so that mucosa and periosteum are completely incised = Full-thickness mucoperiosteal flap raised
                     iii.     Incision should be designed so that it can be closed over solid bone rather than bony defect = Extend incision at least one tooth anterior (mesial of 7) to surgical site
                    iv.     Avoid vital anatomic structures
2.    Remove overlying bone
>       Principles
                       i.     Balance bone removal & tooth sectioning to hasten healing & minimise time of surgery.
All impacted teeth can be removed without sectioning if large amount of bone removed, but removal of excessive bone prolongs healing period and may weaken jaw. Removal of small amount of bone with multiple divisions of tooth may prolong operation unnecessarily.
                      ii.     Amount of bone removed varies with impaction depth, root morphology, & tooth angulation.
                     iii.     Remove bone on occlusal, buccal and distal down to cervical of tooth.
Not removed from lingual aspect to avoid lingual nerve.
                    iv.     Burs: No.8 end cutting bur, used effectively for drilling with a pushing motion.
>       Steps
                       i.     Remove bone on occlusal to expose tooth crown
                      ii.     Cortical bone on  buccal aspect removed down to cervical line
                     iii.     Bur to remove bone between tooth & cortical bone in cancellous bone = Ditching
                    iv.     Provides access for elevators and creates tooth delivery pathway
                     v.     Maxillary: Bone removal usu unnecessary. When required, bone removed on buccal aspect of tooth, down to cervical line to expose entire clinical crown. Usually via periosteal elevator (not bur). Mesial bone might be removed to allow elevator access.
3.    Section tooth
>       Direction in which impacted tooth should be divided depends primarily on impacted tooth angulation. Also divergent roots presence, depth of impaction.
>       Technique
                       i.     Tooth sectioned 3/4th s way towards lingual aspect
                      ii.     Bur not used to section tooth completely through lingual direction (avoid lingual nerve)
                     iii.     Straight elevator inserted into slot made by bur, rotated to split tooth.
>       Mesioangular impaction
Distal half of crown sectioned off at buccal groove to just below cervical line on distal aspect. Remaining tooth removed with No. 301 elevator placed at mesial aspect of cervical line.
OR prepare purchase point in tooth with bur, use crane pick elevator to elevate tooth.
>       Horizontal impaction
Divide crown from roots at cervical line. Crown removed, roots displaced with cryer elevator into space previously occupied by crown. Divergent roots might require sectioning into 2 portions to be delivered individually.
>       Vertical impaction
Occlusal, buccal & distal bone removed. Distal half of crown sectioned and removed. Tooth elevated by applying elevator at mesial aspect of cervical line of tooth.  Posterior aspect of crown elevated first with cryer, mesial aspect elevated with straight elevator. More difficult than mesioangular removal because access around 7 hard, requires more bone removal on b & d.
>       Distoangular impaction
Section crown from roots just above cervical line. Entire crown usually removed as it interferes with visibility and access to tooth root structure. If roots are fused, cryer/ straight elevator used to elevate tooth into space previously occupied by crown. If roots divergent, sectioned then delivered. More distal bone removed,
>       Impacted maxillary teeth rarely sectioned as overlying bone thin and elastic.
>       Impacted teeth elsewhere usually sectioned only at cervical line as this permits removal of crown of tooth, displacement of root into where crown was, removal of root.

4.    Deliver tooth with elevator
>       Elevators: Not to deliver excessive force.
To engage tooth or tooth root and to apply force in proper direction.
Impacted tooth has never sustained occlusal forces, thus PDLs are weak and permit tooth displacement if appropriate bone is removed and force is delivered in proper direction.
>       Commonly used: Straight elevator, Cryer, Crane pick.
>       Difference between extraction and impacted tooth removal.
No luxation of tooth occurs for purpose of expansion of buccal or linguocortical plate. Instead, bone is removed and teeth are sectioned to prepare unimpeded path for tooth delivery.
>       Excessive force may cause unfavouring fracturing of tooth/ buccal bone/ 7/ mandible.


5.    Prepare for wound closure
>       Bone file: Remove any sharp, rough bone edges particularly where elevator was in contact
>       Irrigate with saline to remove all particulate bone chips and debris from wound and under reflected oft tissue flap.
>       Mosquito haemostat: To remove any remnants of dental follicle.
Grasp follicle, lift with slow, steady pressure
à Pulls free from surrounding hard&soft tissue.
>       Final irrigation and thorough inspection
>       Suture: Primary closure.
Initial suture: Through attached tissue on posterior aspect of 7.
Additional sutures placed posteriorly from that position, anteriorly through papilla on mesial of 7/6.
>       Check for adequate haemostasis.
Bleeding can occur from vessel in flap, bone marrow cut with bur, or inferior alveolar vessels.
Specific bleeding points controlled.
Brisk generalised oozing, apply firm pressure with small, moistened gauze pack.
>       Antibiotic application (tetracycline) to help prevent osteitis sicca.

LAop: Classification systems of impacted teeth

Principles of management of impacted teeth
Chapter 9, Contemporary Oral and Maxillofacial Surgery, James R. Hupp

- Primary factor determining difficulty of removal is accessibility
- Majority of classification systems are based on radiograph analysis
-  3 main classification systems; used in conjunction to determine difficulty of an extraction

1. Angulation
  • Angulation of long axis of impacted 8 wrt long axis of adjacent 7
  • Easiest to most difficult to remove:
    Mesioangular (43%), Horizontal (3%), Vertical (38%), Distoangular (6%)
  • Another angulation: Buccal, lingual, palatal, transverse (absolutely horizontal position in bl direction)
2. Relationship to anterior border of ramus (Pell and Gregory; Classes 1/2/3; easiest to hardest)
  • Based on amount of impacted tooth that is covered with bone of mandibular ramus
  • Analyse carefully the relationship between tooth and anterior part of ramus
  • Class I: Mesiodistal diameter of crown is completely anterior to anterior border of ramus
  • Class II: Approximately one-half of crown is covered by ramus
  • Class III: Crown is located entirely within ramus
3. Relationship to occlusal plane (Pell and Gregory; Classes A/B/C)
  • Based on depth of impacted tooth compared with height of adjacent second molar
  • Degree of difficulty is measured by thickness of overlying bone
  • Class A: Occlusal surface of impacted tooth is level or nearly level with (o) of 7
  • Class B: Occlusal surface of impacted tooth between (o) plane and cervical line of 7
  • Class C: Occlusal surface of impacted tooth is below cervical line of 7

LAop: Indications & Contraindications, Pericoronitis

Principles of management of impacted teeth
Chapter 9, Contemporary Oral and Maxillofacial Surgery, James R. Hupp

Indications for removal of impacted teeth
1. Prevention of periodontal disease
2. Prevention of caries
3. Prevention of pericoronitis
  • Definition: Infection of soft tissue around crown of a partially impacted tooh usually caused by normal flora. Usually, bacteria and host defences maintain a delicate balance
  • Causes:
    (a) When host defences are compromised (during minor illnesses, on immunocompromising drugs)
    (b) Following minor trauma from a upper 8
    (c) Food trap beneath operculum
  • Treatment: Mechanical debridement of periodontal pocket under operculum with ChX/ saline irrigation
  • Severity
    (a) Mild: Localised tissue swelling and soreness
    (b) Moderate: Large amount of tissue swelling being traumatised by upper 8? Remove upper 8 immediately + local irrigation for mandibular 8
    (c) Severe: Local swelling and pain, mild facial swelling, mild trismus resulting from inflammation extending into muscles of mastication, low-grade fever? Debride, irrigate, AB
    (d) Very severe: Serious fascial space infections. Trismus <20mm, fever, facial swelling, pain, malaise? Refer to OS; might admit for parenteral AB and careful monitoring
  • Lower 8 should not be removed until s/s of pericoronitis have completely resolved due to increased incidence of post-op complications such as alveolar oestitis, post-op infection, more bleeding, slower healing
  • About operculectomy: Painful, usually ineffective, soft tissue tends to recur
4. Prevention of root resorption
5. Impacted teeth under a dental prosthesis
6. Prevention of odontogenic cysts and tumours
7. Treatment of pain of unexplained origin
8. Prevention of jaw fractures
9. Facilitation of orthodontic treatment
10. Optimal periodontal healing

Contraindications for removal of impacted teeth
1. Age extremes:
  • Bone becomes highly calcified, < flexible. > bone needs to be removed during surgery
  • Slower healing
  • If a tooth has been retained in alveolar process for many years without periodontal disease, caries or cystic degeneration, it is unlikely that these unfavourable sequelae would occur

2. Compromised medical status
3. Probable excessive damage to adjacent structures

General rules
1. All impacted teeth should be removed unless removal is contraindicated
2. Removal of impacted teeth becomes more difficult with advancing age due to increased bone density and compromising systemic diseases (slower healing)
3. Advantages of early removal
  • Reduces post-op morbidity
  • Better healing - both periodontal and nerve recovery
  • Easier to remove as bone is less dense and root formation is incomplete
4. Best age to remove: When roots of teeth are 1/3 to 2/3 formed. Usually between 17-20yo. Average age of complete eruption is 20, but eruption may continue up to 25yo
  • Root morphology
  • Optimal time for removal: Root is 1/3 to 2/3 formed, with blunt ends
  • If <1/3, tooth more difficult to remove because will roll around in socket like a marble
  • Single, conical root or widely separated roots
  • Curvature of roots
  • Direction of root curvature: In a mesioangular impaction, roots curved gently in the distal direction following pathway of extraction can be removed without fracturing. But if roots are straight/curved mesially, the roots commonly fracture if tooth is not sectioned before extraction
  • PDL space; the wider the PDL space, the easier to remove
  • Size of follicular sac
  • Density of surrounding bone. Optimal time for removal 18yo. >35yo = denser bone.
  • Contact with mandibular second molar
  • Relationship to IDN
  • Nature of overlying tissue
5. Cut off age: Over 35yo and impacted tooth shows no signs of disease, should not be removed