Factors influencing young patient arrival date at the orthodontic office: a study of 456 cases / Facteurs influençant la date d'arrivée du jeune patient au cabinet d'orthodontie : une étude sur 456 cas.

Introduction: The arrival date young patient's first orthodontic consultation is unrestricted but may influence the choice of treatment plan as well as its modalities. The objective of this study was to determine the factors that influence the date of the first consultation at the orthodontic office: advice from a third party or a health professional, the patient's gender, the socioeconomic level, the actual need for orthodontic treatment, and the vertical and anteroposterior skeletal dysmorphia. Materials and Methods: Young patient's file younger than 16 years were systematically included. A Wilcoxon and Kruskal-Wallis test was performed in univariate and multivariate analysis. The threshold was 5%. Results: 456 young patients were included. Anteroposterior skeletal discrepancy, referral by an acquaintance, and socioeconomic level appeared to be factors influencing patient arrival date. Gender, actual need for orthodontic treatment, referral from a health professional, and vertical skeletal discrepancy did not influence the arrival date at the office. Discussion: The date of consultation is not related to the actual orthodontic treatment need. Word-of-mouth seems to play an important role. Patients seem to relate an anteroposterior discrepancy to the need to consult an orthodontist, but do not relate it to vertical discrepancy, although ventilation may be related to severe dysmorphia. Conclusion: This study encourages more communication about orthodontic treatment indications with patients and caregivers.

Introduction: La date d'arrivée du jeune patient en première consultation orthodontique est libre mais peut influencer le choix du plan de traitement, ainsi que ses modalités. L'objectif de cette étude était de déterminer les facteurs qui influencent la date de première consultation au cabinet d'orthodontie : le conseil d'un tiers ou d'un professionnel de santé, le genre du patient, le niveau socio-économique, le besoin réel de traitement orthodontique, la dysmorphie squelettique verticale et antéro-postérieure. Matériels et méthodes: Les dossiers de jeunes patients de moins de 16 ans ont été systématiquement inclus. Un test de Wilcoxon et Kruskal-Wallis a été effectué en analyse univariée et multivariée. Le seuil retenu était de 5 %. Résultats: Au total, 456 patients ont été inclus. Le décalage squelettique antéro-postérieur, le fait d'être adressé par une connaissance et le niveau socio-économique semblent être des facteurs influençant la date d'arrivée du jeune patient. Le genre, le besoin réel de traitement orthodontique, le fait d'être adressé par un professionnel de santé, le décalage squelettique vertical n'ont pas d'influence sur la date d'arrivée au cabinet. Discussion: La date de consultation n'est pas liée au besoin réel de traitement. Le bouche à oreille semble jouer un rôle important. Les patients semblent faire le lien entre un décalage antéro-postérieur et la nécessité de consulter un orthodontiste, mais ne le font pas pour le décalage vertical alors que la ventilation peut être liée à des dysmorphies sévères. Conclusion: Cette étude encourage à communiquer davantage sur les indications de traitement orthodontique avec les patients et les soignants.

Measuring Microbial Mutation Rates with the Fluctuation Assay.

Fluctuation assays are widely used for estimating mutation rates in microbes growing in liquid environments. Many cultures are each inoculated with a few thousand cells, each sensitive to a selective marker that can be assayed phenotypically. These parallel cultures grow for many generations in the absence of the phenotypic marker. A subset of cultures is used to estimate the total number of cells at risk of mutations (i.e., the population size at the end of the growth period, or Nt). The remaining cultures are plated onto the selective agar. The distribution of observed resistant mutants among parallel cultures is then used to estimate the expected number of mutational events, m, using a mathematical model. Dividing m by Nt gives the estimate of the mutation rate per locus per generation. The assay has three critical aspects: the chosen phenotypic marker, the chosen volume of parallel cultures, and ensuring that the surface on the selective agar is completely dry before the incubation. The assay is relatively inexpensive and only needs standard laboratory equipment. It is also less laborious than alternative approaches, such as mutation accumulation and single-cell assays. The assay works on organisms that go through many generations rapidly and it depends on assumptions about the fitness effects of markers and cell death. However, recently developed tools and theoretical studies mean these issues can now be addressed analytically. The assay allows mutation rate estimation of different phenotypic markers in cells with different genotypes growing in isolation or in a community. By conducting multiple assays in parallel, assays can be used to study how an organism's environmental context affects spontaneous mutation rate, which is crucial for understanding antimicrobial resistance, carcinogenesis, aging, and evolution.