In the United States, it is estimated that about 1,640,000 HSV-2 seroconversions occur yearly (730,000 men and 910,000 women, or 8.4 per 1,000 persons).In British Columbia in 1999, the seroprevalence of HSV-2 antibody in leftover serum submitted for antenatal testing revealed a prevalence of 17%, ranging from 7% in women 15–19 years old to 28% in those 40–44 years.In Norway, a study published in 2000 found that up to 70–90% of genital initial infections were due to HSV-1.In Nova Scotia, 58% of 1,790 HSV isolates from genital lesion cultures in women were HSV-1; in men, 37% of 468 isolates were HSV-1. History
Herpes has been known for at least 2,000 years. Emperor Tiberius is said to have banned kissing in Rome for a time due to so many people having cold sores. In the 16th-century Romeo and Juliet,  blisters "oer ladies lips" are mentioned. In the 18th century, it was so common among prostitutes that it was called "a vocational disease of women". The term herpes simplex appeared in Richard Boultons A System of Rational and Practical Chirurgery in 1713, where the terms herpes miliaris and herpes exedens also appeared. Herpes was not found to be a virus until the 1940s.Herpes antiviral therapy began in the early 1960s with the experimental use of medications that interfered with viral replication called deoxyribonucleic acid (DNA) inhibitors. The original use was against normally fatal or debilitating illnesses such as adult encephalitis, keratitis, in immunocompromised (transplant) patients, or disseminated herpes zoster.
A phoenix abscess is an acute exacerbation of a chronic periapical lesion. It is a dental abscess that can occur immediately following root canal treatment. Another cause is due to untreated necrotic pulp (chronic apical periodontitis). It is also the result of inadequate debridement during the endodontic procedure. Risk of occurrence of a phoenix abscess is minimised by correct identification and instrumentation of the entire root canal, ensuring no missed anatomy. Treatment involves repeating the endodontic treatment with improved debridement, or tooth extraction. Antibiotics might be indicated to control a spreading or systemic infection. Causes
Phoenix abscesses are believed to be due to a changing internal environment of the root canal system during the instrumentation stage of root canal treatment, causing a sudden worsening of the symptoms of chronic periradicular periodontitis. This instrumentation is thought to stimulate the residual microbes in the root canal space to cause an inflammatory reaction. These microbes are predominantly facultative anaerobic gram-positive bacteria, such as Streptococcus, Enterococcus and Actinomyces species. Another cause of a phoenix abscess is a decrease in a patients resistance to these bacteria and their products. Signs & Symptoms
Clinical Features
PainA common clinical feature is exacerbated and exaggerated pain. There may or may not be associated with pus & suppuration. The signs & symptoms are similar to that of an acute periradicular abscess, but with a periradicular radiolucency present as well. Loss of VitalityThe problematic tooth will have a non-vital pulp with no previous symptoms. Vitality of teeth can be assessed through various means.