Poor Oral Hygiene Contraindications to providing<unk>  and<unk>  include plaque and active caries. It is important to ensure adequate oral hygiene before providing any indirect restoration as failure to manage the caries risk of an individual may result in recurrent caries. Caries risk is defined as “a prediction as to whether a patient is likely to develop new caries in the future”. The restoration itself does not alter the risk, which allows subsequent caries to develop around the indirect restoration placed. This may be caused by plaque retentive features of the restoration, or if the restoration is poorly bonded to the tooth. However, in the main the subsequent caries around a restoration is because the caries risk has not been reduced. Reducing the patients risk of further disease prior to treatment provides predictable results and helps prevent further restorative procedures.1 Parafunctional habits and heavy occlusal forces<unk>  are contraindicated in patients with parafunctional habits and heavy occlusal forces. A Parafunctional habit refers to abnormal functioning of oral structures and associated muscles, for example patients who clench or grind their teeth. Occlusal forces are greater on molars when compared to premolars. Evidence (Fuzzi and Rapelli) has shown greater failure of<unk>  and<unk>  in molars than premolars over an 11.5 year period. The most common cause for failure was porcelain fracture. To ensure longevity it is beneficial to avoid heavy occlusal forces. If a cuspal coverage<unk> is required porcelain should be used as cuspal coverage with composite is contraindicated. Patients under 16. Indirect restorations are contraindicated in patients under 16 as the pulp chamber is still large and wide dentinal tubules increase the stress on the pulp. When preparing a cavity to retain an indirect restoration there is a risk of damage to the nerve supply of a vital tooth. The tooth has not fully erupted and continued active and passive eruption can cause unfavourable margins when the tooth is fully through as the patient is still undergoing skeletal development. Young children may be unable to cope with invasive dental treatment and long procedures, therefore it is advantageous to wait until they are fully cooperative. Unable to tolerate impression taking Patients need to be able to cope with dental impressions as these are required for the fabrication of the indirect restoration. Development of digital impression systems including Lava Chairside oral scanner by 3M, Sirona's CEREC and Cadent iTero System could help patients receive treatment if the contraindication is being unable to withstand conventional impressions. Digital impressions enable production of highly accurate models whilst eliminating patient discomfort. However, these systems are not widely available in dental practices, as of 2018. Alternatives If a tooth has extensive caries or tooth surface loss which would provide difficulty bonding an<unk> or<unk> then it might be more appropriate to consider a full coverage extra coronal restoration. This can protect remaining tooth structure. Direct restorations, for example composite may be beneficial when restorations are small.<unk>  require elimination of undercuts, therefore direct restorations may preserve tooth structure whilst also avoiding unwanted laboratory costs.
Inlays and onlays
Fill and finish
Arden syntax
Archetypal pedagogy
Multiple mini-interview
Rape in English law
Universal design
Arris and Gale Lecture