The placement of a dental crown, a cap fitted over a damaged tooth, restores strength and function. Pain when putting pressure on a crowned tooth signals an underlying issue requiring professional attention. Since the crown is inert, discomfort originates from the tooth structure below, the surrounding gum tissue, or a mechanical problem with the restoration’s fit. Pinpointing the source of this pressure-related pain is the first step toward resolution and ensuring the tooth’s long-term health.
Problems with the Crown’s Occlusion or Fit
A frequent cause of pain upon biting is a crown that is slightly too high, known as occlusal interference or a “high spot.” When the crown contacts the opposing tooth before the others, it absorbs a disproportionate amount of the chewing force. This excessive, uneven pressure irritates the periodontal ligament, which anchors the tooth in the jawbone, leading to inflammation and pain when the tooth is loaded.
The crown’s marginal seal, the tight boundary where the crown meets the natural tooth structure, is significant. If this seal is poor, it can create a microscopic gap that allows oral bacteria and fluids to leak beneath the crown. This leakage can cause sensitivity or mild pain when biting, even before significant decay develops.
A crack in the crown’s material can also cause sharp pain when pressure is applied. Materials like porcelain or porcelain-fused-to-metal can fracture due to trauma or the forces of teeth grinding (bruxism). This fracture can transmit force directly to the prepared tooth underneath, or expose the underlying structure, leading to discomfort.
Pain Stemming from the Underlying Tooth Structure
Pain originating from the tooth underneath the crown often involves the dental pulp, the soft tissue containing nerves and blood vessels. If the crown does not fit tightly or the marginal seal fails over time, recurrent decay can form at the crown’s edge. As this decay progresses inward, it reaches the sensitive dentin and eventually the pulp, and the pressure of biting exacerbates this pain.
The trauma of preparing the tooth for the crown, or pre-existing deep decay, can cause inflammation of the pulp, a condition called pulpitis. This inflammation swells the nerve tissue within the rigid confines of the tooth chamber, making the tooth highly sensitive to pressure changes, which is felt acutely when biting down. If this inflammation, known as irreversible pulpitis, does not subside, the nerve may require a root canal treatment to resolve the infection.
Furthermore, the natural tooth structure beneath the crown may have developed an internal crack, often running vertically or horizontally. When chewing pressure is applied, the fractured segments of the tooth flex slightly, causing a sharp, intense pain. This type of fracture is particularly difficult to diagnose without advanced imaging and is a common cause of biting pain in crowned teeth.
Issues Involving Supporting Gum Tissue
The tissues surrounding the crowned tooth can also be the source of pressure pain. Periodontal disease, or periodontitis, is an infection and inflammation of the gums and the underlying bone supporting the tooth. This inflammation weakens the attachment of the tooth, making it tender and painful when subjected to the force of chewing.
If excess dental cement is not completely removed after the crown is bonded, it can be left under the gumline. This trapped cement acts as a chronic irritant, causing localized inflammation and tenderness in the gum tissue adjacent to the crown, which can mimic biting pain.
A severe infection deep within the tooth or surrounding bone can lead to the formation of a dental abscess. This abscess is a pocket of pus that creates pressure at the root tip. When this pressure builds, the tooth can feel slightly elevated, and biting down on it causes distinct, sharp pain as the force is transmitted to the infected area.
Next Steps for Diagnosis and Resolution
Persistent pain when biting down on a crowned tooth signals that a dental appointment is necessary. The diagnostic process typically begins with a visual inspection and percussion tests, where the dentist gently taps the tooth to gauge sensitivity and pain location. Thermal sensitivity tests may also be used to determine the vitality and health of the tooth’s nerve.
The most informative diagnostic tool is the X-ray, which allows the clinician to visualize the internal tooth structure and the surrounding bone. X-rays can reveal recurrent decay beneath the crown, signs of bone loss indicative of periodontitis, or a dark shadow at the root tip suggesting an abscess. This imaging is crucial for determining the root cause that is not visible clinically.
Treatment depends directly on the diagnosis, ranging from simple to complex. For a high spot, the crown can be adjusted by polishing the occlusal surface to re-establish a balanced bite, often providing immediate relief. If decay or irreversible pulpitis is found, a root canal procedure may be performed through the crown to clean the infected nerve tissue. In cases of significant decay, poor fit, or fracture, the crown must be removed, the underlying issue treated, and a new crown placed.