One or more pain symptoms are present in 65% of people who have depression, and anywhere from 5 to 85% of people who are experiencing pain will also have depression, depending on the setting—a lower prevalence in general practice, and higher in specialty clinics. Depression is often underrecognized, and therefore undertreated, in patients presenting with pain. Depression often coexists with physical disorders common among the elderly, such as stroke, other cardiovascular diseases, Parkinsons disease, and chronic obstructive pulmonary disease. History
The Ancient Greek physician Hippocrates described a syndrome of melancholia (μελαγχολία, melankholía) as a distinct disease with particular mental and physical symptoms; he characterized all "fears and despondencies, if they last a long time" as being symptomatic of the ailment. It was a similar but far broader concept than todays depression; prominence was given to a clustering of the symptoms of sadness, dejection, and despondency, and often fear, anger, delusions and obsessions were included. The term depression itself was derived from the Latin verb deprimere, meaning "to press down". From the 14th century, "to depress" meant to subjugate or to bring down in spirits. It was used in 1665 in English author Richard Bakers Chronicle to refer to someone having "a great depression of spirit", and by English author Samuel Johnson in a similar sense in 1753. The term also came into use in physiology and economics.
Although examination may reveal a fissure on the surface of anterior tooth, radiographic examination is the way. On a periapical radiograph, the invagination lesion will appear as a radiolucent pocket. It is usually seen beneath the cingulum or incisal edge. Larger lesions can appear as fissures. A radio-opaque could be shown. Pulp may be involved and the root canal could have complex anatomy. Two periapical radiographs are often required to make sure that it is not a masked lesion. Cone beam computed tomography (CBCT) is useful in diagnosing DI. It provides clinicians a detailed 3D image and could aid treatment planning. Feasibility of root canal treatment or apical surgery or other procedures could be assessed. Oehlers classification
Class I - Partial invagination. It is limited to the crown of tooth. The lesion does not extend pass the cementoenamel junction (CEJ) or the pulp. Class II - Partial invagination. It extends beyond the crown and CEJ. Pulp may be involved but remain within the root anatomy. There is no communication of the lesion with periodontal ligament (PDL). Class IIIa - Complete invagination. It extends through root and communicates with PDL. It usually does not involve the pulp but can cause anatomical malformation. Class IIIb - Complete invagination. It extends through the root and communicates with PDL through apical foramen. Pulpal anatomy may not be directly involved but can cause disruption to the dental anatomy.