Volunteer participation in tasks atypical to the defined occupational role was a significant risk factor for PTSD. Other risk factors included exposure intensity, earlier start date, duration of time spent on site, and constant, negative reminders of the trauma. Additional research has been performed to understand the social consequences of the September 11 attacks. Alcohol consumption was assessed in a cohort of World Trade Center workers using the cut-annoyed-guilty-eye (CAGE) questionnaire for alcohol use disorder. Almost 50% of World Trade Center workers who self-identified as alcohol users reported drinking more during the rescue efforts. Nearly a quarter of these individuals reported drinking more following the recovery. If determined to have probable PTSD status, the risk of developing an alcohol problem was double compared to those without psychological morbidity. Social disability was also studied in this cohort as a social consequence of the September 11 attacks. Defined by the disruption of family, work, and social life, the risk of developing social disability increased 17-fold when categorized as having probable PTSD. Anthropology
Cultural and medical anthropologists have questioned the validity of applying the diagnostic criteria of PTSD cross-culturally. Trauma (and resulting PTSD) is often experienced through the outermost limits of suffering, pain and fear. The images and experiences relived through PTSD often defy easy description through language. Therefore, the translation of these experiences from one language to another is problematic, and the primarily Euro-American research on trauma is necessarily limited.
The facilitation of eruption of the second permanent molars to the space of the first permanent molar removes the burden of continuous restorative treatment.A favourable occlusion may be acquired following a well-planned treatment and this eliminates the need for fixed orthodontic appliances therapy. However, a comprehensive discussion of the possible need of orthodontic sequelae and treatment is important.Favorable eruption position of the second permanent molar may result if the first permanent molar is extracted when the child is at the age of between 8–10 years old. This is when the crown formation of the second permanent molar is complete and the mineralization of the bifurcation is commenced.Extraction of first permanent molars before 8 years old increases the chances of the unerupted second permanent premolar drifting distally. Extraction after the age of 10 years reduces the likelihood of the mesial movement of the second permanent molar in to the first permanent molar space and may result in tilting of the second permanent molar. Epidemiology
Since first recognised in the late 1970s, the condition has puzzled many people. It is thought to be a unique defect unlike other enamel disturbances e.g. fluorosis or amelogenesis imperfecta.Many prevalence studies have now been published from findings across the globe. However, there is a large amount of variation across the results of these studies. It is reported that the prevalence of MIH ranges from 3.6% to 40.2%  with an estimate of 14.2% of the global population suffering.