The fractured palatal cusp of the upper premolar is likely due to excessive occlusal forces exerted over time, especially during parafunctional habits like bruxism (teeth grinding) or clenching. The patient’s large masseters and bitten fingernails suggest bruxism or clenching, which leads to increased stress on the teeth. Over time, this can weaken tooth structure, making it more susceptible to fracture, even during relatively low-stress activities like eating a sandwich.

What is the significance of the anterior wear?

The anterior wear, especially the dentine exposure on the upper canines, indicates a significant amount of tooth surface loss, typically caused by parafunctional habits like bruxism. Canines play a crucial role in guiding the occlusion and protecting the posterior teeth during lateral movements (canine guidance). The loss of this guidance could shift the load to other teeth, like the upper premolars, further contributing to their fracture. The exposed dentine also increases the risk of sensitivity and further wear.

What additional precautions might you take in this case when you plan for a definitive restorative work?

1. Assessment of Parafunctional Habits: •Address the underlying cause of the excessive forces, likely bruxism or clenching. Consider a thorough evaluation and a potential referral to a specialist to assess for any contributing factors such as stress, anxiety, or sleep disorders. • Fabrication of a night guard (occlusal splint) may be recommended to protect the teeth from further damage.
   2. Occlusal Analysis:
      • Perform a detailed occlusal analysis to identify any interferences, especially in lateral and protrusive movements. Address occlusal discrepancies that could contribute to abnormal forces on teeth.
      • Check for the need to adjust canine guidance, as the wear may have altered the normal function.
   3. Restorative Material Selection:
      • Consider using a durable material such as porcelain, zirconia, or composite for the restoration, especially for posterior teeth under high stress.
      • A crown may be necessary for the fractured tooth to provide full coverage and strength, particularly if the fracture is subgingival.
   4. Subgingival Fracture Considerations:
      • Ensure proper isolation during restorative procedures, as the subgingival fracture may complicate the seating of a restoration.
      • Crown lengthening or orthodontic extrusion may be required to ensure that the margins of the restoration are accessible and that a proper seal can be achieved without violating the biological width.
   5. Patient Education and Follow-up:
      • Educate the patient about the potential for ongoing damage if bruxism is not managed.
      • Regular follow-up is important to monitor the restoration and assess for further wear or damage due to parafunctional habits.

References: Practical Procedures in Dental Occlusion, First Edition. Ziad Al-Ani and Riaz Yar. © 2022 John Wiley & Sons Ltd.