4 - Orofacial Trauma

Question 1

When would you extract a primary tooth that is intruded and why?

Answer 1

1. If the root tip is exposed through the gingival tissue (facial cortical plate has been fractured) - bc of the poor healing prognosis
2. If the tooth fails to re-erupt after 6 months - bc any partial ankylotic changes could impede the path of eruption of the permanent incisor
3. If there is a concomitant root fracture where the coronal fractured segment poses any type of aspiration risk - extract the coronal segment and leave the apical segment alone
4. Impingement on the permanent tooth bud - extract to minimize the damage to the permanent tooth

Question 2

What direction are the majority of intrusions in primary incisors?

Answer 2

Labial direction

Question 3

What percent of intruded primary incisors will re-erupt within six months?

Answer 3

88%

Question 4

After an intrusion of the primary incisor, when would you see significant re-eruption?

Answer 4

The teeth should demonstrate significant re-eruption (although not necessarily complete) by two months. The majority of intruded incisors will re-erupt within six months.

Question 5

What percent of children participating in sports wear mouth guards during practices?

Answer 5

1% to 5%.

Question 6

When does a patient need a tetanus booster after oral trauma?

Answer 6

If the last tetanus booster was five or more years prior and the wound is contaminated with soil/debris, another toxoid booster is indicated.

Question 7

When do you refer for medical consult after oral trauma?

Answer 7

1. Amnesia
2. Nausea/vomiting
3. Headache
4. Lethargy/irritability/confusion
5. Loss of consciousness

Question 8

What kind of root fracture in a primary tooth would give a good prognosis?

Answer 8

Good prognosis:
1. Root fractured in the apical third present a good prognosis

Poor prognosis:

1. More coronal the fracture
2. Mobility of the coronal segment

Question 9

What are the ways that root fractures heal?

Answer 9

1. Calcified tissue (bony healing) - fragments in close contact with fracture line barely visible
2. Interposition of connective tissue - fragments are close but separated by PDL space
3. Interposition of bone and connective tissue - fragments surrounded by PDL are separated by an ingrowth of bone
4. Interposition of granulation tissue

Question 10

What is the most common way root fractures heal?

Answer 10

Calcified tissue and interposition of connective tissue.

Question 11

Before splinting what risks:benefit analysis must you consider?

Answer 11

1. Patient cooperation
2. Ability to provide adequate isolation if a resin splint is used
3. Parental compliance with needed follow-up care

Question 12

Does discoloration after dental trauma warrant extraction? When do you not extract and when do you extract?

Answer 12

Transient discoloration immediately following injury is common. This discoloration is most often reddish or grayish. It does not warrant immediate treatment.

Discoloration that first appears well after the trauma occurred may be indicative of changes in pulp vitality and potential necrosis.

Question 13

After dental trauma, how long will vitality tests yield false-negative results?

Answer 13

Up to 3 months.

Vitality tests are not indicated on the day of injury and even up to 3 weeks post-trauma bc they provide unreliable information.

Question 14

What is the most common sequelae to luxation injuries to immature permanent teeth?

Answer 14

Pulp canal obliteration

Question 15

For a complicated crown fracture, how quickly must a partial pulpotomy be performed to assure optimal healing?

Answer 15

Optimal healing occurs if the partial pulpotomy is performed soon after the injury. However, positive outcomes have been reported when this treatment was delayed days to weeks after the injury. Best practice is to complete the procedure as soon as adequate assistance and facilities are available. This may mean deferring treatment until the following day.

Question 16

What complications compromise the success of a partial pulpotomy?

Answer 16

A partial pulpotomy must be performed as aseptically as possible. Primary causes of failure include:

1. Inadequate isolation and lack of an absolute seal by the temporary restoration.
2. Fracture lines extending subgingivally.

Question 17

Can a tooth treated by a partial pulpotomy be completely restored immediately?

Answer 17

It may be possible to complete the final restoration on a tooth treated with a partial pulpotomy.

• -However, since luxation injuries frequently accompany such severe crown fractures, deferring the final restoration until the PDL has healed is recommended.
• -Also final restoration should be deferred if the tooth is mobile.

Question 18

What are the options for treatment of an immature permanent tooth with a healthy pulp vs totally necrotic pulp?

Answer 18

Healthy pulp (vital pulp techniques)

1. Pulp cap
2. Partial pulpotomy
3. Apexogenesis

Necrotic pulp (non-vital pulp technique)

1. Apexification
2. Revascularization

Question 19

How large of an overjet is a significant risk factor for dental trauma?

Answer 19

Overjet greater than 3mm and/or Angle Class II malocclusion are significant risk factors for dental trauma.

Increased overjet and class II malocclusion are often associated with lip incompetence, another significant risk factor for dental trauma.

Question 20

According to the ADA, what are the ideal recommendations for a mouth guard?

Answer 20

1. Be properly fitted to the wearer’s mouth and accurately adapted to his or her oral structures.
2. Be made of resilient material and cover all remaining teeth on one arch, customarily the maxillary.
3. Stay in place comfortably and securely.
4. Be physiologically compatible with the wearer.
5. Be relatively easy to clean.
6. Have high-impact energy absorption and reduce transmitted forces upon impact.

Question 21

What change do you see if there is an alveolar fracture?

Answer 21

An occlusal change due to misalignment of fractured segment is often noted.

Question 22

When should periodontal evaluation of the teeth be performed after alveolar fracture?

Answer 22

Periodontal evaluation of teeth in injured alveolar segment should be performed once osseous healing has stabilized, usually six to eight weeks after the injury.
-I.e., Do not do perio probing until osseous healing has occurred, which may take six to eight weeks.

Question 23

In an alveolar fracture, what do you do if the alveolar segment cannot be immediately reduced?

Answer 23

1. Controlled pressure may be applied in an occlusal or coronal direction to facilitate repositioning.
2. If still unsuccessful, an open reduction approach may be required, involving laying a flap for direct visualization.

Question 24

In a root fracture, what factors favor healing?

Answer 24

1. Immature root development
2. Limited displacement of coronal fragment: 1mm or less
3. Repositioning to optimal position, i.e., close approximation of fragments
4. Flexible splinting: significantly better healing rates occur when light splints are applied with minimal manipulation of the fragments

Question 25

How long do you splint for permanent tooth root fractures?

Answer 25

Middle and apical third root fractures - splint for 4 weeks | Cervical third root fracture - splint up to 4 months

Question 26

How should a root canal be completed for a permanent tooth with a root fracture?

Answer 26

The pulps of approximately three-quarters of root-fractured teeth survive, but when they fail, it is almost always in the coronal fragment. If pulp necrosis develops, treatment is to complete root canal therapy on the coronal fragment only, up to the level of the fracture line.

Question 27

For a permanent tooth with an extrusion, when should root canal therapy be completed?

Answer 27

Immature permanent tooth - have the potential to revascularize, so monitor for several weeks prior to beginning root canal treatment. Mature permanent tooth - very unlikely to revascularize, so should extirpate the pulp within three weeks to prevent inflammatory resorption.

Question 28

Will extruded teeth have normal mobility when the splint is removed?

Answer 28

No. Extruded teeth are splinted for two weeks. The PDL re-attachment process is not complete at that time, so normal mobility may not yet be reached. Evidence indicates that healing is improved under these conditions and the patient is instructed to avoid biting on the injured teeth until normal mobility has returned.

Question 29

What are the radiographic signs that indicate successful healing of root-fractured teeth?

Answer 29

Radiographic signs of success: 1. Presence of lamina dura 2. No signs of bone or root resorption

Question 30

What are the signs of an intruded permanent tooth?

Answer 30

1. High-pitched, metallic sound upon percussion 2. Loss of physiologic mobility 3. Relative infraocclusion as the child's maxilla grows 4. Loss of PDL space radiographically

Question 31

Intruded permanent teeth are at high risk for what complications?

Answer 31

1. Pulp necrosis 2. Marginal bone loss 3. inflammatory and replacement root resorption

Question 32

When can you reposition intruded permanent teeth?

Answer 32

Closed apex teeth intruded 6mm or less can be repositioned with light orthodontic forces. Some clinicians recommend mildly luxating the tooth prior to applying the orthodontic force. Open apex immature teeth intruded 6mm or less can be allowed to reposition spontaneously. But rapidly reposition orthodontically if no movement is noted within 3 weeks.

Question 33

What must you do differently in a root canal for an intruded permanent tooth?

Answer 33

Bc the tooth is likely to ankylose and undergo replacement resorption, do not place gutta percha unless healing is indicated by presence of lamina dura and no signs of resorption.

Question 34

What is the importance of ankylosis in a young patient?

Answer 34

Significant future maxillary growth is anticipated. The tooth will begin to infraocclude, causing periodontal defects and an esthetic dilemma.

Question 35

What clinical and radiographic signs indicate successful treatment of intrusion injuries?

Answer 35

Clinically: 1. Tooth is normal position 2. Tooth responds normally to mobility and percussion tests Radiographically: 1. No replacement or inflammatory root resorption 2. Intact lamina dura around the root

Question 36

If a patient calls the dental office about an avulsed permanent tooth, what should you advise them to do?

Answer 36

The person answering the phone at the doctor's office should advise responsible person with the injured child to replant the tooth immediately.

Question 37

How should someone manage an avulsed tooth while still at the site where the injury occurred?

Answer 37

1. Hold tooth by the crown, rinse gently with water, do not scrub root surface 2. Immediately replant tooth at site of injury, if possible. After replantation, bite on gauze or a clean towel to avoid tooth aspiration. 3. If replantation is not possible, place tooth in Hank's Balanced Salt Solution, cold milk, saline or saliva (in that order of preference) to maximize vitality of the root surface cells.

Question 38

For an avulsed permanent tooth, how much extra-oral dry time would lead to ankylosis and replacement resorption?

Answer 38

Dry time greater than 60 minutes leads to ankylosis and replacement resorption.

Question 39

What is the best transport medium for an avulsed permanent tooth?

Answer 39

HBSS > cold milk > saline or saliva 1. Hank's Balanced Salt Solution - most favorable storage medium but is rarely available. 2. Cold Milk - place tooth in a small cup of milk, then place the cup in a bowl of ice. Do not use water, it is hypotonic and will quickly kill PDL cells.

Question 40

What antibiotics should be given for a permanent tooth avulsion?

Answer 40

If the patient is 8 years old or older and 45kg or more: Doxycycline 100mg q 12h first day, then 50mg q 12h days 2 to 10. Doxycycline is the first choice due to anti-resorptive properties. If the patient is under 8 years old: Penicillin VK 20-50mg/kg/d in four divided doses for seven days.

Question 41

For a permanent tooth avulsion with an extra-oral dry time greater than 60 minutes, what can you do to delay replacement resorption?

Answer 41

Soaking the tooth in fluoride for 20 minutes may delay but not prevent replacement resorption.

Question 42

After replantation of an avulsed permanent tooth, when would decoronation of the tooth be recommended?

Answer 42

If the tooth becomes ankylosed and infrapositioned greater than 1mm. This is done to preserve the alveolar bone.

Question 43

How can pulp necrosis cause inflammatory root resorption?

Answer 43

Toxic byproducts of necrosis provoke an inflammatory reaction at the PDL that can destroy the root within weeks.

Question 44

What are the radiographic signs of inflammatory root resorption?

Answer 44

Typically a raggged resorption of lateral root surface and possibly the apical area.

Question 45

What can you do to enhance the chance of revascularization in an avulsed permanent tooth?

Answer 45

Enhances revascularization: 1. Replantation of tooth within 15 minutes 2. Covering the root with topical minocylin hydrochloride microspheres (Arestin) 3. Soaking in a 1% doxycycline solution prior to replantation

Question 46

When should you suture a tongue laceration?

Answer 46

There is no evidence indicating that the routine suturing of minor tongue lacerations has any positive effect on healing. Uncontrollable hemorrhage and potential for airway compromise are the only immediate reasons for suturing a tongue laceration.

Question 47

What are some local factors that may influence soft tissue healing?

Answer 47

Local factors that may influence soft tissue healing include low oxygen tension to the region and corresponding ischemia, infection and localized edema.

Question 48

What is the cause of localized soft tissue color change after oral soft tissue trauma?

Answer 48

There is a potential for localized tissue color change and contour change due to damage to melanocytes. Ablation of gingival melanocytes may result in loss of pigmentation. Melanocyte repopulation of traumatized tissues are thought to originate in the free gingiva.