Traumatic Injuries of TheTeeth

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Traumatic Injuries of theTeeth

• CONCUSSION

– Definition. The term concussionindicates a crushing injury to the

vascular structures at the toothapex and to the periodontal ligament, resulting in inflammatory edema. Only minimal loosening or displacement of thetooth occurs.The injury frequently results in theelevation of the tooth out of the

socket so that its occlusal surfacemakes premature contact on



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a ograp ca eva ua on ooral and maxillofacial

trauma

• Rajan mishra

• BDS final year



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content

Traumatic Injuries of theTeeth

• CONCUSSION

•

LUXATION• AVULSION

• FRACTURES OF THE TEETH

• Dental Root Fractures

• Crown-Root Fractures

TRAUMATIC INJURIES TO THE



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LUXATION

• An adequate history is helpful inidentifying luxation and orderingthe appropriate radiographs.

Subluxated teeth are in theirnormal location

• but are abnormally mobile. There

may be some blood flowing fromthe gingival crevice, indicatingperiodontal ligament damage.

Subluxated teeth are extremely



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Radiographic features.

• Radiographic examinations of luxated teeth may demonstratethe extent of the injury to the

root, periodontal ligament, and alveolar bone. A radiographmade at the time of injury serves

as a valuable• reference point for comparison

with subsequent radiographs. As

with dental concussion, the



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Management.

• A subluxated permanent toothmay be restored to its normalposition by digital pressure

shortly after the accident. If swelling precludes repositioning,minimal reduction of antagonists

to relieve discomfort may be• necessary. Stabilize teeth by

splinting to prevent further

damage to the pulp and



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AVULSION

• Definition. Avulsion (or exarticulation) is the termusedto describe the complete

displacement of a tooth from thealveolar process. Teeth may beavulsed by direct trauma when

the force is applied directly tothe tooth, or by indirect trauma(e.g., when indirect force isapplied to teeth as the result of the jaws striking together).



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Clinical features.

• Maxillary central incisors arethe teeth most often avulsed from both dentitions. The

appearance of the alveolar process around the missingtooth depends on the time

between its loss and the clinical examination. Typically this injury occurs in a relatively young agegroup, when the permanent central incisors are just erupting



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• In a recent avulsion the laminadura of the empty socket isapparent and usually persists for

several months. The replacementof the socket site

• with new bone requires months

and, in some cases, years. Asnew bone forms, the oppositewalls of the healing socket

approach each other, reducing



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FRACTURES OF THETEETH

• Dental Crown Fractures

– Definition. Fractures of the dental crown account for about 25% of

traumatic injuries to the permanent teeth and 40% of injuries to thedeciduous teeth. The most commonevent responsible for the fractureof permanent teeth is a fall,followed by accidents involvingvehicles (e.g., bicycles,automobiles) and blows fromforeign bodies striking the teeth.



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Clinical features.

• Fracture of the dental crownsmost frequently involvesanterior teeth. Infractions, or

cracks in the enamel, are quitecommon but frequently are not

• readily detectable. Illuminating

crowns with indirect light(directing the beam in the longaxis of the tooth) causes cracks

to appear distinctly in the



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reference

• Oral radiology principles andinterpretation –White and Pharoah



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• Uncomplicated fractures do not involve the pulp. Uncomplicated

•

crown fractures that do notinvolve the dentin usually occurat the mesial or distal corner of the maxillary central incisor.

Loss of the central portion of • the incisal edge is also common.

Fractures that involve dentin can

be recognized by the contrast in



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• The radiograph providesinformation regarding thelocation and extent of the

fracture and the relationship tothe pulp chamber, as well as thestage of root development of the

involved tooth (Fig.). This initialfilm also provides a means of comparison for follow-up studiesof the involved teeth.

•



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Dental RootFractures

• Definition. Fractures of toothroots are uncommon and account for 7% or fewer of traumatic

injuries to permanent teeth and for about half that many indeciduous teeth. This difference

probably results from the fact • that the deciduous teeth are less

firmly anchored in the alveolus.



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Clinical features.

• Most root fractures occur inmaxillary central incisors. Thecoronal fragments are usually

displaced lingually and slightlyextruded. The degree of mobilityof the crown relates to the level

of the fracture: the closer thefracture is to the apex, the morestable the tooth is. When testingthe mobility of a traumatizedtooth, place a finger over the



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• Fractures of the dental root may occur at any level and involveone or all the roots of

multirooted teeth. Most of thefractures confined to the root occur in the middle third of the

root. The ability of the film toreveal the presence of aroot fracture depends on the degreeof distraction of the fragmentsand whether the x-ray beam is in



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Differential diagnosis

• The superimposition of softtissue structures such as the lip,ala of the nose, and nasolabial

fold over the image of a root maysuggest a root fracture

• To avoid this diagnostic error,

note that the soft tissue imageof the lip line usually extendsbeyond the tooth margins.

Fractures of the alveolar



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Management.

• Fractures in the middle or apical third of l ateral incisor also isevident. Note how the soft tissue

outline the root of permanent teeth can be manually reduced to of the nose simulates a

fracture of the central incisor root tip.

• the proper position and

immobilized. Prognosis is



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Crown-Root Fractures

• Definition. Crown-root fracturesinvolve both the crown and roots. Although uncomplicated

fractures may occur, crown-root fractures usually involve the

pulp. About twice as many affect

the permanent as the deciduous• teeth. Most crown-root fractures

of the anterior teeth are the

result of direct trauma. Many



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Clinical features.

• The typical crown-root fractureof an anterior tooth has a labial margin in the gingival third of

the crown and courses obliquely to exit below the gingival attachment on the lingual

surface. Displacement of • the fragments is usually minimal.

Crown-root fractures

occasionally present with



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• These fractures are often not visible

• in the radiographic imagebecause the x-ray beam is rarelyaligned with the plane of thefracture. Also, distraction of the

fragments is usually not present.The vertical fractures of crownand root that are mainly

tangential



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Management.

• Removal of the coronal fragment permits the evaluationof the extent of the fracture. If

the coronal fragment includes asmuch as 3 to 4 mm of clinical

• root, successful restoration of

the tooth is doubtful andremoval of the residual root isrecommended. Also, if the

crown-root fracture is vertical,



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Vertical Root Fractures

• Definition. Vertical root fracturesrun lengthwise from the crowntoward the apex of the tooth.

Usually both sides of a root areinvolved. The crack is usually oriented in the facial-lingual

plane in both anterior and posterior teeth. These fracturesusually occur in the posterior teeth in adults, especially inmandibular molars. They are



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Clinical features.

• Patients with vertical root fractures complain of persistent dull pain (cracked tooth

syndrome), often of longduration. This pain may be

• elicited by applying pressure to

the involved tooth. Pain may benonexistent or mild. The patientmay have a periodontal lesion

resembling a chronic abscess or



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• If the central ray of the x-ray beam lies in the plane of thefracture, the fracture may be

visible as a radiolucent line onthe radiograph. Usually,

• however, radiographs are not

useful in identifying vertical rootfractures in their early stages.Later, after the development of

an inflammatory lesion, there



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Management.

• Single-rooted teeth with verticalroot fractures must be extracted.Multirooted teeth may be

hemisected and the intactremaining half of the toothrestored with endodontic

therapy and a crown.



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TRAUMATIC INJURIESTO THE FACIAL BONES

• Injury to the facial bones mayoccur in one or more of thebones. Facial fractures most

frequently occur in the zygomaor mandible and, to a lesserextent, in the maxilla.

Radiography plays a crucial rolein the diagnosis andmanagement of traumaticinjuries to the facial bones. Theappropriate radiologic



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Mandibular Fractures

• The most common mandibularfracture sites are the condyle,body, and angle, followed less

frequently by theparasymphyseal region, ramus,coronoid process, and alveolus.

The most common cause of mandibular

• fractures is assault, followed by

automobile accidents, falls, and



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Mandibular BodyFractures

• Definition.

• The mandible is the mostcommonly fractured facial bone.It is important to realize that afracture of the mandibular bodyon one side is frequently

accompanied by a fracture of thecondylar process on the

• opposite side. Trauma to the

anterior mandible may result in a



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• The radiographic examination of a suspected fracture should include a panoramic view;

however, it is important tosupplement this film with

• right-angle views. These include

occlusal and extraoral viewssuch as the posteroanterior andsubmentovertex skull views.

Frequently such supplemental



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Differential diagnosis.

• The superimposition of soft tissue shadows on the image of the mandible may simulate

fractures. A narrow air spacebetween the dorsal surface

• of the tongue and the soft palate

superimposed across the angleof the mandible in a panoramicimage may appear as a fracture.

The air space between the dorsal



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Management.

• The management of a fracture of the mandible presents a varietyof surgical problems that involve

the proper reduction, fixation,and immobilization

• of the fractured bone. Minimally

displaced fractures are managedby closed reduction andintermaxillary fixation, whereas

fractures with more severely



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Mandibular CondyleFractures

• Definition.

• Fractures in the region of thecondyle can be divided intocondylar neck fractures andcondylar head fractures.Condylar neck fractures are

more common and are locatedbelow the condylar head. When acondylar neck fracture occurs,

the head is usually displaced



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Clinical features.

• The clinical symptoms of afractured condylar process arenot always apparent, so the

preauricular area must becarefully examined and palpated.A condylar fracture may be

suspected when the cliniciancannot palpate the condyle inthe external ear canal when the

jaw is closed. Movement of the

jaw may cause crepitus. The



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• Radiographic examination of thecondyles should always includelateral and anteroposterior views

of each condyle. Appropriatelateral projections

• include panoramic (Fig. 27-12),

Parma (Fig. 27-13), and lateraloblique views of the ramus andcondylar regions. Frontal views

include reverse-Towne's and



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Management

• The technical details of treatingcondylar fractures varyaccording to whether one or

both condyles are involved, theextent of displacement, and

• the occurrence and severity of

concomitant fractures. Thetreatment is directed to relieveacute symptoms, restore proper

anatomic relationships, and

f h



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Fractures of theAlveolar Process

• Definition. Simple fractures of the alveolar process may i nvolvethe buccal or lingual cortical

plates of the alveolar process of the maxilla or mandible.Commonly these fractures are

associated with traumaticinjuries to teeth that are luxatedwith or without dislocation.Several teeth are usually

affected, and the fracture line is



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Clinical features.

• A common location of alveolarfractures is the anterior aspectof the maxilla. Simple alveolar

fractures are relatively rare inthe posterior segments of thearches. In this location, fracture

of the buccal plate usuallyoccurs during removal of amaxillary posterior tooth.Fractures of the entire alveolar

process occur in the anterior and



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Radiographic features

• Intraoral radiographs often donot reveal fractures of a singlecortical wall of the alveolar

process, although evidenceexists that the teeth have beenluxated. However, a fracture of

the anterior labial cortical platemay be apparent on a lateralextraoral radiograph if somebone displacement occurs and if

the direction of the x-ray beam



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Management.

• Fractures of the alveolar processare treated by repositioning thedisplaced teeth and associated

bone fragments with digitalpressure. Gingival lacerationsare sutured. If the luxated

permanent teeth are splintedand stable, intermaxillaryfixation is not necessary.Permanent teeth are splinted for

about 6 weeks.



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MAXILLARY FRACTURES• Midface Fractures

• Definition. Fractures of themidfacial region may be limited to the maxilla alone or may involve other bones, includingthe frontal, nasal, lacrimal,

zygoma, vomer, ethmoid, and sphenoid. Such complex fractures may be

•

quite variable but often follow

H i t l F t (L



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Horizontal Fracture (LeFort I)

• Definition. The Le Fort I fractureis a relatively horizontal

• fracture in the body of themaxilla that results indetachment of the alveolarprocess of the maxilla from the

middle face. It is the result of atraumatic force directed to thelower maxillary region. The

fracture line



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• The radiographic examinationreveals fractures of the nasalbones, both frontal processes of

the maxilla (and ethmoid andfrontal sinuses,

• if involved), and the infraorbital

rims on both sides (and the floorof both orbits). Fractures in thezygoma or zygomatic process of

the maxilla, separation of the



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Management.

• The treatment of this fracture isaccomplished by reduction of thedownward displacement of the

maxilla. The maxilla is fixed inplace by intermaxillary

• wires or arch bars. Usually

treatment includes openreduction and interosseouswiring of the infraorbital

•

rims. The accompanying

C i f i l Di j ti



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Craniofacial Disjunction(Le Fort III)

• Definition. A Le Fort III midfacefracture results when thetraumatic force is of sufficient

magnitude to completelyseparate the middle third of thefacial skeleton from the cranium.

The fracture line usually extendsthrough the nasal bones and thefrontal processes of the maxillaor nasofrontal and maxillofrontal

sutures, across the floors of the



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Clinical features.

• Craniofacial disjunctionproduces a clinical appearancesimilar to pyramidal fracture.

How- ever, this injury isconsiderably more extensive.The soft

•

tissue injuries are severe, withmassive edema. The nose maybe blocked with blood clot, or

blood, serum, or cerebrospinal



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• The radiographic projections of Le Fort III fractures usually arehazy because of extensive soft

tissue swelling. The mainradiographic findings

• are separated nasofrontal,

maxillofrontal,zygomaticofrontal, andzygomaticotemporal sutures

(Fig. 27-19). The nasal bones,



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Management.

• The associated severe soft tissueinjury necessitates initialhemorrhage control, airway

maintenance, and repair of lacerations. Surgery may bedelayed until the edema has

sufficiently resolved. Thetreatment

• of transverse fractures is

complicated because fixation of



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Zygomatic Fractures

• Definition. Unilateral fracturesinvolving the zygoma are of twotypes: zygomatic arch fractures,

in which just the arch isfractured, and zygomaticcomplex fractures, in which the

zygomatic bone is separated from its frontal,

• maxillary, and temporal

connections. Bilateral zygomatic



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Clinical features.

• Flattening of the upper cheek with tenderness and dimpling of the skin over the zygomatic arch

and zygomaticofrontal sutureand a fullness of the lower

• cheek may occur after zygomatic

complex fracture. Step defectsmay be palpated in thezygomaticofrontal area and

along the infraorbital rim. Some



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• Because of edema obscuring theclinical features, theradiographic examination may

provide the only means of determining the presence and

• extent of the injury. The

occipitomental (Waters')radiograph provides an image of the whole zygoma and maxillary

sinus. The submentovertex



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Management.

• When symptoms include minimaldisplacement of the zygomaticarch and no cosmetic deformity

or impairment of eye movement,no treatment

• may be required. Otherwise,

reduction is usually indicated.Fractures of the arch may bereduced through an intraoral or

extraoral approach. If a

MONITORING THE



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MONITORING THEHEALING OF FRACTURES

• Radiographic examination of thefacial bones after trauma isusually necessary to measure

the degree of reduction fromtreatment and to monitor thecontinued immobilization of the

fracture site during repair. The• monitoring of fracture repair

should include examination of

both the alignment of the



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Clinical features.

• If the fragment is not distally impacted, it can be manipulated by holding onto the teeth. If the

fracture line is at a high level,the fragment may include

• the pterygoid muscle

attachments, which pull thefragment posteriorly andinferiorly. As a result, the

posterior maxillary teeth contact



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• This fracture may be difficult todetect. The views to use are the

posteroanterior, lateral skull,

and Waters' projections and CT scans. Both maxillary sinuses areusually radiopaque and may

show airfluid • levels. The lateral view may

disclose a slight posterior

displacement of the fragment



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Management.

• If the fracture is not displaced and is at a relatively low level inthe maxilla, it can be treated by

intermaxillary fixation. Thosethat are high, with the fragment displaced posteriorly or with

pronounced separation, requirecraniomaxillary fixation inaddition to intermaxillary fixation. A unilateral horizontal

fracture is usually immobilized

Pyramidal Fracture (Le



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Pyramidal Fracture (LeFort II)

• Definition. The Le Fort II fracturehas a pyramidal appearance onthe posteroanterior skull

radiographhence the name. Itresults from a violent forceapplied to the central region of

the middle third of the facialskeleton. This force separatesthe maxilla from the base of theskull by causing fractures of the

nasal bones and frontal



Clinical features.

• In contrast to the Le Fort I(horizontal) fracture,characterized by only slight

swelling about the upper lips,the Le Fort II injury results inmassive edema and marked

swelling of the middle third of the face. Typically, anecchymosis around the eyesdevelops within minutes of the

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Traumatic Injuries of TheTeeth