For example, in a study published in 2003 titled "The five-factor model and personality disorder empirical literature: A meta-analytic review", the authors analyzed data from 15 other studies to determine how personality disorders are different and similar, respectively, with regard to underlying personality traits. In terms of how personality disorders differ, the results showed that each disorder displays a FFM profile that is meaningful and predictable given its unique diagnostic criteria. With regard to their similarities, the findings revealed that the most prominent and consistent personality dimensions underlying a large number of the personality disorders are positive associations with neuroticism and negative associations with agreeableness. Openness to experience
At least three aspects of openness to experience are relevant to understanding personality disorders: cognitive distortions, lack of insight (means the ability to recognize ones own mental illness here) and impulsivity. Problems related to high openness that can cause problems with social or professional functioning are excessive fantasising, peculiar thinking, diffuse identity, unstable goals and nonconformity with the demands of the society.High openness is characteristic to schizotypal personality disorder (odd and fragmented thinking), narcissistic personality disorder (excessive self-valuation) and paranoid personality disorder (sensitivity to external hostility). Lack of insight (shows low openness) is characteristic to all personality disorders and could help explain the persistence of maladaptive behavioral patterns.The problems associated with low openness are difficulties adapting to change, low tolerance for different worldviews or lifestyles, emotional flattening, alexithymia and a narrow range of interests.
Regional odontodysplasia  is an uncommon developmental abnormality of teeth, usually localized to a certain area of the mouth. The condition is nonhereditary. There is no predilection for race, but females are more likely to get regional odontodysplasia. The enamel, dentin, and pulp of teeth are affected, to the extent that the affected teeth do not develop properly. These teeth are very brittle. On radiographs the teeth appear more radiolucent than normal, so they are often described as "ghost teeth". Most cases are considered idiopathic, but some cases are associated with syndromes, growth abnormalities, neural disorders, and vascular malformations. Permanent teeth usually show effects of regional odontodysplasia if the deciduous tooth was affected. Many of these teeth do not erupt, and those that do have an increased risk of caries and periapical inflammation. Treatment and prognosis
Treatment and prognosis are usually based upon keeping these teeth and preserving the alveolus. For erupted teeth, endodontics is an option if the tooth is devitalized and restorable. For unerupted teeth, function can be restored with a removable partial denture until all major growth has been completed and a final restoration can be placed. References


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