The involved cusp can be determined by biting on individual cusps separately. Tooth Slooth II (Professional Results Inc., Laguna Niguel, CA, USA) and Fractfinder (Denbur, Oak Brook, IL, USA) are commercially available tools. Epidemiology
Aetiology of CTS is multifactorial, the causative factors include:

previous restorative procedures. occlusal factors; patients who suffer from bruxism, or clenching are prone to have cracked teeth. developmental conditions/anatomical considerations. trauma
others, e.g., aging dentition or presence of lingual tongue studs.Most commonly involved teeth are mandibular molars followed by maxillary premolars, maxillary molars and maxillary premolars. in a recent audit, mandibular first molar thought to be most affected by CTS possibly due to the wedging effect of opposing pointy, protruding maxillary mesio-palatal cusp onto the mandibular molar central fissure. Studies have also found signs of cracked teeth following the cementation of porcelain inlays; it is suggested that the debonding of intracoronal restorations may be caused by unrecognized cracks in the tooth. Treatments
There is no universally accepted treatment strategy, but, generally, treatments aim to prevent movement of the segments of the involved tooth so they do not move or flex independently during biting and grinding (stabilisation of the crack) to prevent propagation of the crack. Provisionally, a band may be placed around the tooth or a direct composite splint can be placed in supra-occlusion to minimize flexing.
However other clinical signs which may lead to the diagnosis of CTS includes wear faceting indicating excessive forces perhaps from clenching or grinding or the presence of an isolated deep periodontal pocket which may symbolise a split tooth. Removing restorations may help to visualise fracture lines but should only be carried out after gaining informed consent from the patient, as removing a restoration may prove to be of little diagnostic benefit. Tactile examination with a sharp probe may also aid diagnosis. Gentian Violet or Methylene Blue Stains
Dyes may be used to aid visualisation of fractures. The technique requires 2–5 days to be effective and a temporary restoration may be required. The structural integrity can be weakened by this method, leading to crack propagation. Transillumination
Transillumination is best performed by placing a fibre optic light source directly onto the tooth and optimal results can be achieved with the aid of magnification. Cracks involving dentine interrupt the light transmission. However, transillumination may cause cracks to appear enlarged as well as causing colour changes to become invisible. Radiographs
Radiographs offer little benefit in visualising cracks. This is due to the fact that cracks propagate in a direction which is parallel to the plane of the film (Mesiodistal) however radiographs can be useful when examining the periodontal and pulpal status. Bite Test
Different tools can be used when carrying out a bite test which produce symptoms associated with cracked tooth syndrome. Patients bite down followed by sudden release of pressure. CTS diagnosis is confirmed by pain on release of pressure.