These differences may be due to rates of high blood pressure and atherosclerosis, which are more easy to find in older persons. In 101 people free of heart disease during 24 hours Holter monitoring, 39 had at least 1 PVC, and 4 at least 100. Heart disease was excluded after physical examination, chest x-ray, ECG, echocardiography, maximal exercise stress test, right- and left-heart catheterization and coronary angiography. In 122,043 United States Air Force flyers and cadet applicants during approximately 48 seconds of ECG 0.78% (952 males) had PVC within all age groups, but with increased incidence with increasing age. Ventricular ectopy is more prevalent in men than in women of the same age data from large, population-based studies indicate that the prevalence is less for young white women without heart disease and greater for older African American individuals with hypertension. References
Further reading


== External links ==
A primordial cyst is a developmental odontogenic cyst. It is found in an area where a tooth should have formed but is missing. Primordial cysts most commonly arise in the area of mandibular third molars. Under microscopes, the cyst looks like an odontogenic keratocyst (also called a Keratocyst odontogenic tumor) whereby the lesions displays a parakeratinized epithelium with palisading basal epithelial cells. The term "Primordial cyst" is considered an outdated term and should be avoided. Most "primordial cysts" are actually Keratocyst odontogenic tumors (KOTs). References

Kahn, Michael A. Basic Oral and Maxillofacial Pathology. Volume 1. 2001.