There are certain conditions when a tooth requires a Root canal treatment (RCT) and a crown fabrication, however, sometimes a crown is required without an RCT to compensate for the lost tooth structure or to prevent sensitivity. Usually, the conditions that require crown placement without RCT fall under a separate category.
A. Root canal treatment (RCT) and a crown fabrication
The conditions under this category can be:
- Irreversible pulpitis
- Pulp necrosis
- Discolouration of the teeth
- Dental abscess
- Fractured tooth leading to pulp exposure
- Bruxism causing pulp exposure and wearing off the crown
- Failed dental bridge
- Pulp exposure during caries removal (mechanical exposure)
B. Crown placement without RCT
- Sensitivity due to gingival recession
- Affected tooth with a poor crown to root ratio (core build-up and crown placement)
- In amelogenesis imperfecta and dentinogenesis imperfecta
- Enamel hypoplasia of a single or multiple teeth
- Discoloured teeth/ staining
ROOT CANAL TREATMENT (RCT) AND CROWN FABRICATION
Irreversible pulpitis usually is a consequence of long-standing reversible pulpitis that has not been resolved. The pulp cannot return to its normal state anymore and hence, Root canal treatment is required for the dissolution of the symptoms. When we perform root canal treatment, crown placement is most imperative to provide structural durability and overall strength.
Usually, after long-standing irreversible pulpitis, the result is pulp necrosis. Once the pulp has necrosed, the symptoms subside and become duller such as a dull throbbing pain or at an instance, no pain at all. This condition if left untreated can lead to periapical inflammation and bone loss.
Pulp necrosis causing tooth discolouration
In a few cases, pulp necrosis can present itself as discolouration of the tooth. The discolouration is usually bluish-red due to blood accumulation in the pulp chamber. This can be overcome by internal bleaching of the pulp chamber. However, when this is not probable then a crown can be placed after endodontic debridement.
The usual treatment for a dental abscess is the extraction of the offending tooth and draining of the accumulated pus. The patient is given antibiotics and observed over time. Usually, the extraction of the involved tooth lowers the pain and pressure. Another option of preference in a few cases of periapical abscess could be an RCT after drainage. This helps alleviate the pain and resolves the condition, hence, allowing the bone formation in the previous infection occupied space. Later, a crown is prepared and seated.
Fractured tooth leading to pulp exposure
Crown fractures are a common way for pulp exposure if the fracture is usually below the cementoenamel junction. In a few cases, the pulp can even be more coronal. When the pulp is exposed and decision precedes RCT then crown placement is a must for the integrity of the natural tooth replication.
Bruxism causing pulp exposure and wearing off the crown
Grinding the teeth at night during sleep is usually referred to as Bruxism. Bruxism causes the exposure of the dentine and later pulp if the habit is not ceased. Pulp exposure might require Root canal treatment with the fabrication of a crown.
Failed dental bridge
Repugnant designed bridges normally require removal of the bridge and treating the involved damaged teeth which were the supporting abutments. During the preparation of these abutment teeth to accept the bridge, excessive griding has shown to lose most of the crown structure. Over time, these weak abutments may not be able to bear the occlusal stresses. Furthermore, the stresses of retainers can initiate fractures or pulp exposures. Treatment of choice will be RCT and crown placement.
Pulp exposure during caries removal (mechanical exposure)
This is caused by the operator, removing caries close to the pulp causing exposure of the pulp. Usually, Calcium hydroxide paste is applied to the exposed pulp and the patient is under observation. If that secondary dentine is formed then the procedure is a success, which means a filling such as composite is the last step. On the other hand, if pulpitis symptoms are observed then RCT with crown placement will be the choice of treatment.
CROWN PLACEMENT WITHOUT RCT
Sensitivity due to gingival recession
Improper tooth brushing technique has shown to be the most prominent factor in gingival recession in all ages. The best way to prevent gingival recession is to use BASS technique of tooth brushing and use a soft bristle toothbrush. The recession reveals the underlying root surface which is sensitive to hot, cold, touch and brushing. That is why when other options of decreasing sensitivity are of no use, crown placement might be beneficial.
Sometimes, extensive loss of tooth structure due to tooth grinding at night time might require crown placement as the best and most feasible choice.
Affected tooth with a poor crown to root ratio (core build-up and crown placement)
Excessive loss of the crown which leaves the crown to root ratio less than 1:1 is not the ideal tooth to be saved. Instead, it should be removed. When the choice is made to save this tooth, a core build-up and post-placement is essential before placement of the crown.
In amelogenesis imperfecta and dentinogenesis imperfecta
These conditions severely affect both the primary and permanent dentition. In amelogenesis imperfecta, the enamel is faulty and chips off easily. Whereas, in the case of dentinogenesis imperfecta, the dentine is weak. Hence, cannot support the enamel which leads to chipping of the enamel. Crown placements will prevent further chipping and damage to the tooth structure.
Enamel hypoplasia of single or multiple teeth
In this condition, the enamel is deficient in the amount which leads to abrasion of the tooth upon grinding the food or with minor traumas. Full coverage crowns have shown to be of real advantage in this condition.
Discoloured teeth/ staining
There are several reasons why a tooth becomes discoloured other than pulp necrosis, hence, the fault of discolouration can be hidden by placing a crown. The intrinsic stains are usually permanent stubborn stains such as tooth fluorosis, dental trauma, pulp necrosis, tetracycline stainings, internal resorption and many others. Few stains which were initially external tooth stains can overtime progress to becoming intrinsic stains. Crown placement is the most practical treatment is such cases.