Magister Scientiae Dentium - MSc(Dent) / Background: Dental age is an indicator of the physiological maturity of growing children. Different methods for estimating the dental age in comparison to the chronological age were proposed in the literature. Objective: The aim of this study was to compare the accuracy of two methods i.e. the Phillips and Proffit methods in estimating the dental age in a sample of South African children at the Tygerberg dental faculty. Methods: A retrospective study was conducted by randomly selecting 100 panoramic radiographs with known chronological age. The sample contained an equal number of girls and boys (50 in each group) and the chronological age ranged between 6 and 11 years. Dental age for each radiograph was estimated using the Phillips and the Proffit methods respectively. The mean difference between dental and chronological age was calculated. Dental and chronological ages were compared using overall bias and random errors. Results: The results showed that for the girls’ sample, the Phillips method underestimated the age by 4 months which is statistically significant (p-value =0.03). The Proffit method underestimated the age by 2 days which is not statistically significant (p-value =0.97). Both methods however have the same frequency of random errors. For the boys’ sample, Phillips’ method underestimated the age by 6 months which is statistically significant (p-value <0.0001). Proffit’s method underestimated the age by 2 months which is not statistically significant (p-value= 0.15). The Phillips method was shown to have fewer random errors in boys. Discussion: The above mentioned results showed that for dental age estimation for girls, Proffit’s method would be more appropriate. This rationale is explained by the conclusion that it only underestimates the age by 2 days and has the same frequency of random errors as Phillips’ method. However, if one had to choose between the two methods for boys, the situation should be evaluated carefully. For boys, the Phillips method has fewer random errors but a larger overall bias (6 months) whereas Proffit’s method has more random errors but less overall bias (2 months). The choice between the two methods should therefore depend on the purpose of the estimation. If the method is used for estimating the age in a single individual with an unknown chronological age, Phillips’ method would be more preferable. However, if the method is used for age estimation in populations with a known mean chronological age, Proffit is preferred. Conclusion: Proffit’s description for dental development has been shown to be accurate in estimating the DA. It may therefore be considered to be a legitimate DA estimation method and not just a developmental description for the dentition.

Magister Chirurgiae Dentium (MChD) / Aging is a biological process under the influence of genetic and pathological factors wh ich can be more or less advanced in different individuals with the same, chronological age. Silverman (1961) defined age as a three-dimensional phenomenon wherein there is a constant interaction between chronologie age, physiologic age and psychologic age. Vinton (1964) also points out that there are physiologic, pathologic, psychologic and sociologic changes which are unique to the latter span of life. These changes are not synonomous with illness as long as they fall within the physiologic limits of normality. If these limits are exceeded the changes are pathological in character. Age is a phase of life which brings about changed circumstances and a new pattern of life which must be adapted to and accepted. This may necessitate an invironmental change which causes a loss of friends and social standing and may bring about a feeling of insecurity in some people, suppressing the incentive to live for the future. To counter these emotions it is imper~tive to create a quality of life in which the aged can be productive within the limits of their physical abilities and which will give them the assurance that they are still needed by society. Life expectancy is determined by the circumstances under which people live. The average age of life expectancy during the Roman period and the Middle Ages was 25 to 30 years; today it is 70 years (Sharry 1974). Nature normally maintains an equilibrium between young and old so that each can provide for the other's needs. Modern science and technology however have upset that balance and brought about new developments in medicine ich have succeeded in increasin and reducin infant mortality, causing the ectancy explosion. This has brought about a situatiop where 10 million humans are born and only 3 million die every month; thus the inflow into life far exceeds the outflow and there is consequently a global increase of 80 million people per year. At this rate the world population will double itself by the end of this century (Pistorius 1978). Birth control has been encouraged as a counter measure to this and the result has been a marked drop in the birth rate, especially in the more advanced countries of the world. This changing relationship between the birth and death rates is referred to as the population-shift. In the U.S.A. 4% of the total population was over the age of 65 years at the beginning of this century. In 1975 the figure was 10% and at the present rate of population-shift will be 20% by the end of this century (Winkler 1977). In England and Wales 6% of the total population was over the age of 65 years in 1931, 10% in 1951 and 12% in 1962. In Scotland 7% was over the age of 65 years in 1931, 9% in 1951 and 10% in 1962 (Storer 1965). In Canada 4,8% of the total population was over the age of 65 years in 1921 and 7,8% in 1971. The average life expectancy was 50 years in 1900 and 70 years in 1960 (Sherman 1970). This pattern of change is also evident in the Republic of South Atrica but there is a marked variation in the different ethnic groups (White, Asian, Coloureds and Blacks) making up the South African population.

<p>The study of work motivation has yielded many applicable theories. This thesis investigated how older employees viewed factors that have been linked to the advancement of age and believed to affect work motivation. Three different conceptualisations of age were included in the study; organisational age, chronological age and life stage. By using a qualitative approach, participants were allowed to shed light on this complex area and give their own views on possible age effects. More specifically, changes in needs and values, the effects on goal setting and the development of skills were investigated. Chronologically younger employees placed greater value in their careers and reported that they would continue to work even if they became financially independent. Older employees attributed less importance to their careers and said that they would choose early retirement in order to have more time if they had money to enjoy it.</p>

The study of work motivation has yielded many applicable theories. This thesis investigated how older employees viewed factors that have been linked to the advancement of age and believed to affect work motivation. Three different conceptualisations of age were included in the study; organisational age, chronological age and life stage. By using a qualitative approach, participants were allowed to shed light on this complex area and give their own views on possible age effects. More specifically, changes in needs and values, the effects on goal setting and the development of skills were investigated. Chronologically younger employees placed greater value in their careers and reported that they would continue to work even if they became financially independent. Older employees attributed less importance to their careers and said that they would choose early retirement in order to have more time if they had money to enjoy it.

This thesis investigates the question: Can Experience Design be applied to create a perception shift from elderly as a burden to elderly as a resource for society? This is done by researching the social norms about ageing and the aged in Swedish society. To conduct this research I put together a focus group of 7 people with different professional backgrounds and ages ranging from 23 to 74. In four workshops I used design-led research methods to research these “mental models”. Using participatory theatre techniques we investigated the personal view of the ageing process. And through discussions and design thinking we articulated the often unspoken social norms. In the workshops we defined our current social norms regarding ageing as Aged Thinking. A counter philosophy was developed called Ageless Thinking. In order to create a change in mindset from Aged Thinking to Ageless Thinking a tool was developed called the Enticon. With this tool people can show what their focus is in life right now regardless of their chronological age. The Enticon was introduced at the Konstfack Spring Exhibition 2013 and also as a web based application.

The purpose of the study is to determine what degree of relationship exists between chronological age and performance in the first grade.

The problem of this study was to determine the relationship between chronological age and reading achievement and between chronological age and personality development in school children.

No

Objetivo: Comparar los métodos de Demirjian, Nolla y Cameriere para la estimación de la edad según la edad cronológica en una población peruana. Materiales y métodos: El diseño del estudio es de tipo descriptivo, de corte transversal. Se seleccionaron 193 radiografías panorámicas aleatoriamente de niños de 6 a 14 años de edad. Se compararon la edad cronológica (EC) y la edad dental (ED) según los métodos de Nolla, Demirjian y Cameriere, utilizando las Pruebas de Rangos de Wilcoxon y Kruskall Wallis. Resultados: La media de la EC fue de 8.77±2.34 y 8.90±2.04 años para el género femenino y masculino, respectivamente. La diferencia de medias de la EC y ED de acuerdo con los métodos Nolla años, Demirjian y Cameriere años fue de -0.38, 0.96 y -0.29 años, respectivamente, para la muestra total de estudio. Conclusiones: Se encontró una correlación positiva para los tres métodos estudiados, sin embargo, el método de Demirjian mostró una diferencia estadísticamente significativa con una subestimación de -0.91 años en la muestra total. Asimismo, el método de Cameriere fue el que tuvo más cercanía a la edad cronológica. / Aim: The aim of this study is to compare Demirjian, Nolla and Cameriere methods for the estimation of dental age in peruvian population. Materials and Methods: This retrospective and cross-sectional study included 193 panoramic radiographs randomly selected from children aged between 6 and 14 years. Chronological age (CA) and dental age (DA) were compared using the Wilcoxon and Kruskall Wallis Range Tests. Results: The mean was 8.77 ± 2.34 and 8.90 ± 2.04 years of the CA for the female and male gender, respectively. The difference in means of the CA and DA according to the Nolla, Demirjian and Cameriere methods were -0.38, 0.96 and -0.21 years, respectively, for the total study sample. Conclusions: A positive correlation was found for the three methods studied, however, the Demirjian method showed a statistically significant difference with an underestimation of -0.91 years in the total sample. Also, the method of Cameriere was the closest to the chronological age. / Tesis

SammanfattningMineralisering och utveckling av visdomständer kan användas som åldersindikator i övre tonåren och används för asylsökande utan identifikation eller födelseattest. Utvärderingen görs med hjälp av dentala röntgenbilder och olika tolkningsmodeller.Målet med den aktuella studien var att undersöka åldersbedömningsmetoder på röntgenbilder av visdomständers tillförlitlighet och överensstämmelse med fokus på populationsgrupper och etnicitet. Detta är av vikt då resultat från en sådan bedömning ligger till grund för juridiska beslut huruvida en individ är vuxen eller ett barn (över eller under 18 år).En systematisk sökning genomfördes i PubMed, Embase och Cochrane enligt PRISMA-modellen, och 23 artiklar som uppfyllde inklusionskriterierna granskades av två observatörer enligt en modifierad QUADAS 2 och tio artiklar bedömdes ha låg risk för bias.Populationsbeskrivningarna var bristande. Detta leder till svårigheter att utföra bedömningar av artiklars resultat och precision, därmed också jämförelser mellan olika studier. Problemet ligger på en generell nivå då definitioner är osäkra, men samtidigt i de separata artiklarna då de inte redovisat någon definition.Det var svårt att jämföra de inkluderade artiklarna då deras syften och metoder varierade. Huvudfyndet var att de flesta artiklarna konkluderade att användningen av visdomstanden som en åldersindikator i de övre tonåren är en otillräcklig metod. Användning och betydelse av dess resultat bör därför ifrågasättas. / AbstractThe mineralization and development of the third molars can be used as an indicator of age in the upper teens and is used in purpose of assessing age in asylum seekers without identification or birth certificates. The evaluation is determined with dental radiographs and different methods of interpretation.The aim of the study was to investigate the accuracy and precision of different age estimation models of radiographs of third molars, focusing on population groups and ethnicity. This is of great importance since the results of an age assessment constitute the basis in a juridical outcome, deciding whether an individual is an adult or a child (over or under 18 years of age). A systematic search of PubMed, Embase and Cochrane was made according to the PRISMA-statement, and 23 articles which met the inclusion criteria were assessed using a modified QUADAS 2 by two observers, ten of these were graded as having low risk of bias.Population groups were poorly described, leading to difficulties in evaluating results and precision, thereby also comparisons between different studies. The problem both lay at a general level where definitions are ambivalent, but also in the separate articles where definitions are missing.It was hard to compare the included papers since their aims and methods varied. The main finding was that most of the articles concluded that the use of the third molar as an age indicator in the upper teens is an insufficient system. The use and impact of the results should thereby be questioned.