Structurally, pulp stones can be classified as true and false pulp stones. True pulp stones are made up of dentine that is lined by odontoblast. True pulp stones are quite rare. On the other hand, false pulp stones are made up of concentric layers of mineralised tissue around blood thrombi, collagen fibres, or dying and dead cells. Histopathology
Histologically, there are two types of stones: (1) stones with regular calcifications (2) stones with irregular calcifications. For regular calcification, the pulp stones are smooth, round or ovoid with concentric laminations. It is commonly found in the coronal pulp. As for irregular calcifications without laminations, pulp stones may have the shape of rods or leaves and the surface is rough. It is more common in the radicular pulp. Pulp stones with regular calcification grow in size by addition of collagen fibrils to their surface, whereas the irregular type of pulp stones are formed by calcification of pre-existing collagen fibres. Pulp stones may also form around epithelial cells such as remnants of Hertwigs epithelial root sheath. It is presumed that epithelial remnants are able to induce adjacent mesenchymal stem cells to differentiate into odontoblasts. Associations
A pilot study was done with patients with cardiovascular disease (CVD) and it shows increased incidence of pulp stones in teeth with patients with CVD compared to healthy patients without CVD. There are also researchers which suggest the link between pulpal calcification and carotid artery calcification, despite not having a strong proof  on this correlation.
Frequent TTH is defined as ten or more episodes of headache over the course of one to fourteen days per month for greater than three months, or at least twelve days per year, but less than one-hundred eighty days per year. Infrequent TTH is defined as ten or more episodes of headache for less than one day per month or less than twelve days per year. Furthermore, all sub-classes of TTH can be classified as having presence or absence of pericranial tenderness, which is tenderness of the muscles of the head. Probable TTH is utilized for patients with some characteristics, but not all characteristics of a given sub-type of TTH. Differential diagnosis
Extensive testing is not needed as TTH is diagnosed by history and physical. However, if symptoms indicative of a more serious diagnosis are present, a contrast enhanced MRI may be utilized. Furthermore, giant cell arteritis should be considered in those 50 years of age and beyond. Screening for giant cell arteritis involves the blood tests of erythrocyte sedimentation rate (ESR) and c-reactive protein. Migraine
Oromandibular dysfunction
Sinus disease
Eye disease
Cervical spine disease
Infection in immunocompromised
Intracranial mass
Idiopathic intracranial hypertension
Medication overuse headache
Secondary headache (headache due to other disorder)
Giant cell arteritis ( ≥50 years of age)
Dermatochalasis

Prevention
Lifestyle
Good posture might prevent headaches if there is neck pain.Drinking alcohol can make headaches more likely or severe.Drinking water and avoiding dehydration helps in preventing tension headache.People who have jaw clenching might develop headaches, and getting treatment from a dentist might prevent those headaches.Using stress management and relaxing often makes headaches less likely.Biofeedback techniques may also help.