Trauma: Crown Fracture

Illustration of a complicated crown fracture: an oblique enamel-dentin fracture across the incisal part of an upper incisor exposes the pulp, with the missing fragment outlined.

A crown fracture is a break in the crown of the tooth. If it stays in enamel and dentin and the pulp is not exposed, it is uncomplicated. If the fracture reaches the pulp, it is complicated, and then how far the root has developed decides what I do. There are 5 categories of crown fractures:

Uncomplicated crown fracture
Complicated crown fracture, Complete Development, without fragment
Complicated crown fracture, Complete Development, with fragment
Complicated crown fracture, Incomplete Development, without fragment
Complicated crown fracture, Incomplete Development, with fragment

1. Uncomplicated Crown Fracture (No Pulp Involvement)

The management for immature and mature teeth is the same. The goal is to stop bacteria from getting in through the open dentinal tubules, and the way to do that is a high-quality restoration (Love 1996). Without a seal, healing drops by 25% (Robertson 2000; Andreasen 1970; Ravn 1981). If a quality restoration is going to be delayed, seal the dentin with glass ionomer or composite.

If the patient brings the crown fragment, it can be reattached. (Demarco 2004).

Uncomplicated crown fracture, no fragment,.

This 10 year old patient presented with an uncomplicated crown fracture on #8. There was the part that was missing, but also an oblique fracture that approximated the bone. We removed the splintered fragment, and decided to restore all of it with composite. Some tissue was removed in order to perform a custom resin matrix with Opaldam. Filtek composite was used. The mottling can be a challenge. We mixed some Permaflow opaquer with flowable and painted it with a microbrush. At 6 months the tooth still tested vital.

Angled periapical radiograph of the upper central incisors, including #8; date 12/30/2011 burned in — Presentation radiograph.

Upper anterior teeth at presentation, with the incisal edge of #8 fractured — Presentation radiograph.

Upper anterior teeth after treatment of #8, including the adjacent lateral — After.

Upper central incisors after treatment of #8 — After.

Both centrals, no pulp involvement.

Both upper centrals with the incisal edges broken off and the pulp not exposed. The patient brought both fragments, and both were reattached. One fragment was chipped, so the missing part was restored with composite. The restored photo and radiograph are from the same day.

Periapical radiograph of the upper central incisors with the incisal edges of both fractured — Presentation radiograph.

Upper anterior teeth at presentation, with the incisal edges of both central incisors fractured — Presentation radiograph.

Both upper central incisors after the fragments were reattached — Fragments reattached, same day.

Periapical radiograph of the upper central incisors after the fragments were reattached — Fragments reattached, same day.

2. Complicated Crown Fracture, Complete Development, Without Fragment

No fragment to put back, so once the pulp is treated the tooth gets a restoration.

A mature central, no fragment.

A fully developed upper central with the incisal edge broken off and no fragment to put back. The pulp was exposed, and the general dentist sealed it with composite. The tooth was symptomatic, so it got root canal treatment, a fiber post with LuxaCore and a composite veneer. Here it is at the 2.5-year recall.

Periapical radiograph of the upper central incisors with the incisal edge of one central fractured away; date 1/23/2014 burned in — Presentation radiograph.

Upper anterior teeth at presentation, with the incisal edge of one central incisor fractured away — Presentation radiograph.

Mirror view under rubber dam of the palatal side of the fractured central incisor — Under the dam, palatal view.

Mirror view under rubber dam of the palatal access, with a fiber post seated in the canal — Under the dam, palatal view.

Upper anterior teeth after restoration of the fractured central incisor — Composite veneer.

Periapical radiograph after root canal treatment of the central incisor, with a post in the coronal part of the canal; date 8/5/2016 burned in — Composite veneer.

3. Complicated Crown Fracture, Complete Development, With Fragment

I don’t perform Cvek partial pulpotomies on mature teeth. If the patient brings the fragment, it can go back on. I carry it back with a mounting jig; see Reattaching the fragment: the mounting jig below. Case 2 (closed apex, the crown fragment carried in putty) and Cases 6 and 7 (root canal treatment, fragment reattached) follow this path. The fragment was rebonded at the same visit as the root canal treatment. Case 5 walks through the jig step by step.

A mature central with a crown fracture. The pulp was exposed, so this one got root canal treatment, then the fragment rebonded. Here it is at 1.5 years in orthodontics.

Periapical radiograph of a fully developed upper central incisor with a crown fracture — Complete development, closed apex.

Upper anterior teeth at presentation with a fractured central incisor and bleeding gingiva — Complete development, closed apex.

Periapical radiograph after root canal treatment of the fractured central incisor — After root canal treatment.

Periapical radiograph at the 1.5-year recall — After root canal treatment.

Placing a post through the fragment.

Another central with the crown broken off and the pulp exposed. In this case the fragment was greater than 50% of the crown, which predisposes the tooth to refracture, especially in clumsy patients. So in those instances, placing a post through the fragment makes sense to mitigate the risk of future re-breaking. The root canal was completed, then the fragment rebonded. The tooth was re-accessed, and the post placed through the access. The access was then restored.

Periapical radiograph of the upper central incisors with the crown of one incisor broken off — Presentation radiograph.

Under rubber dam, the broken crown fragment beside the root with blood on the fracture surface — Presentation radiograph.

Second periapical radiograph with a post in the canal and a film holder in place — Post in place, another angle.

Three tapered posts with yellow, red and black rings — Post in place, another angle.

Periapical radiograph of the upper central incisor with a root canal filling, a post and the crown fragment reattached — Final radiograph.

Second periapical radiograph of the restored upper central incisor from another angle — Final radiograph.

Fiber post, fragment rebonded.

This was another case. The pulp was exposed, so the tooth got root canal treatment and a fiber post, and then the fragment rebonded. The fracture line is visible, which led us to feathering and placing composite to camouflage the line on subsequent cases.

Upper anterior teeth at presentation, with the incisal part of one central incisor fractured away and a red spot on the fractured surface — Presentation.

The fractured central incisor isolated under rubber dam, with white tape around the neighboring teeth — Presentation.

Upper anterior teeth with the fragment rebonded on the central incisor; an arrow points to the visible fracture line — Fragment rebonded; the arrow shows the fracture line.

Post-op periapical radiograph of the central incisor after root canal treatment, with the fragment in place; date 10/8/2010 burned in — Fragment rebonded; the arrow shows the fracture line.

Camouflaging the fracture line.

This was a similar case. The pulp was exposed, so the tooth got root canal treatment and a post, and then the fragment rebonded. However, an effort was made to camouflage the fracture line. You can see where we made vertical striations in an effort to feather in the veneer. The post op shows a little dehydration but the line isn’t as pronounced if it exists at all.

Upper central incisor with the crown broken off at the gum line, front view — Presentation.

Wider front view of the fractured upper central incisor and the lower teeth — Presentation.

The broken crown fragment held in a green putty jig in a gloved hand — The crown fragment in a putty jig.

Periapical radiograph of the fractured upper central incisor with a root canal filling — The crown fragment in a putty jig.

Close view of the crown fragment back in place with the fracture line visible — The fragment back in place.

Upper anterior teeth after the crown fragment was reattached — The fragment back in place.

4. Complicated Crown Fracture, Incomplete Development, Without Fragment

For incompletely developed or immature teeth, my go-to is the Cvek partial pulpotomy. The determination of an open apex coupled with large canal space is made radiographically.

Calcium hydroxide: pulp healing 94–100% (Cvek 1978, 1983; Fuks 1987).
MTA: bridge formation, biocompatible, and it establishes a seal (Pitt Ford 1996; Menezes 2004; Torabinejad 1995, 1997; Koh 1997).
Biodentine- Similar success rates as above with minimal to no staining (Haikal 2000,Qudeimat 2017)

With an open apex, pulp healing also means the root can keep developing and that means more peri-cervical dentin which is critical for long term tooth survival. Using a diamond bur 3-4mm of pulp is removed using water. A pellet soaked in Lidocaine with 1:50 epi usually stops the bleeding. Then barrier material like MTA or Biodentine is added using the Maps carrier (Armamentarium below). After the partial pulpotomy, the tooth is restored and followed. Since there is no fragment to bond, a composite restoration is necessary with possible indirect restoration in the future.

Cvek partial pulpotomy with Biodentine and Composite Restoration

Biodentine Cvek partial pulpotomy on an upper central incisor: preoperative and postoperative radiographs, the Biodentine placement, a clinical photo and the 2017 recall radiograph — Cvek partial pulpotomy with Biodentine.

5. Complicated Crown Fracture, Incomplete Development, With Fragment

With an open apex, pulp healing also means the root can keep developing. The Cvek partial pulpotomy above is my go-to here too.

If the fragment comes in, it can go back on with the mounting jig; see Reattaching the fragment: the mounting jig below.

Part 1: An open apex, Cvek partial pulpotomy with MTA.

Periapical radiograph of an immature upper central incisor with a crown fracture, root outline and fracture marked — Incomplete development, open apex.

Mirror view of the fractured incisor under rubber dam with the pulp preparation for a partial pulpotomy — Incomplete development, open apex.

Restored upper central incisor after the partial pulpotomy — Restored.

Periapical radiograph after the partial pulpotomy and restoration — Restored.

Part 2: The patient returned with the fragment broken off again.

A central with the incisal part of the crown broken off, and the fragment in hand, again. We noticed some significant staining from the MTA (white) over the years. The tooth was bleached for a few weeks- kinda rare to get this clear of an image of a dental bridge. We put a seal over it before bleaching. Once the desired color was achieved, the clear jig carried the fragment back, and it was bonded under rubber dam. We added some feathering and composite veneer to mask the line and provide some additional resistance against refracture.

Upper central incisor with the incisal part of the crown broken off, front view — Presentation.

Mirror view from the palatal side of the fractured upper central incisor — Presentation.

A testing probe touching the fractured upper central incisor — Composite Shade Matching

Close front view of the fractured upper central incisor — Composite Shade Matching

Clear bite registration material being placed over the crown fragment and the neighboring teeth — Fragment in position with first aliquot of bite registration

The clear bite registration jig covering the crown fragment and the neighboring teeth — Fragment in position with first aliquot of bite registration

Blue etchant being applied to the crown fragment while it sits in the clear jig — Etching the fragment in the jig.

Under rubber dam, the crown fragment seated on the tooth with a wooden wedge between the teeth — Etching the fragment in the jig.

Under rubber dam, the neighboring teeth covered and the central incisor ready for etching — Matrix in place.

Blue etchant covering the central incisor under rubber dam — Matrix in place.

Close front view of the reattached upper central incisor — After, close-up.

Periapical radiograph of the upper central incisors with a radiopaque restoration in the crown of one incisor — After, close-up.

Reattaching the fragment: the mounting jig

When the fragment comes in with the patient, I use a mounting jig to carry it back to where it broke off. The jig is clear bite registration material set over the fragment and the neighboring teeth. It is done in two aliquots. Once it sets, the fragment sits in the jig, and the jig seats on the neighbors. It acts as a handle for etching and bonding.

I use Clearfil bonding. The diamond treatment with composite camouflages the fracture line. The Teflon tape prevents composite from bonding to adjacent teeth. The curved-tip syringe is used for placing Biodentine or MTA. Finishing strips are part of the setup.

Armamentarium

Cartridge of clear bite registration material — Clear bite registration material: the jig.

Clear bite registration cartridge loaded in a dispensing gun — Clear bite registration material: the jig.

Thin finishing strips — Finishing strips.

Metal syringe with a curved tip — Finishing strips.

Follow-up and prognosis

Monitor at 3 weeks, 6 weeks, 12 weeks, 6 months, 9 months and 12 months, then yearly for five years. At every visit, I am looking for two things: resorption and necrosis.

When the pulp doesn’t make it

Here is what I count toward a diagnosis of necrosis in a traumatized tooth:

No response to EPT or thermal testing, together with percussion sensitivity
Color change
Pain to palpation
Increased mobility after the tooth had initially stabilized
Radiographic pathology

Lack of sensibility alone is not enough to diagnose necrosis, especially in a developing tooth (Klein 1978). A traumatized pulp can go quiet and still be alive.

If it is necrotic: an immature tooth gets apexification (calcium hydroxide or an apical plug of MTA), and a mature tooth gets conventional root canal treatment. More on that in the overview.

Back to the overview: Endodontic Management of Traumatized Teeth: When to Jump In

This is education, not a substitute for your own clinical judgment.