Not all electronic foramen locators are accurate in teeth with enlarged apical foramina: an in vitro comparison of 5 brands.

INTRODUCTION: Electronic working length measurement during root canal treatment in teeth with enlarged apical foramina is a challenge. The aims of this in vitro study were (1) to assess the influence of foramen widening on the accuracy of 5 different electronic foramen locators (EFLs) and (2) to compare the accuracy of EFLs in different foramen sizes. METHODS: The following EFLs were used: MiniApex, Root ZXII, iPex, Propex II, and Elements Apex Locator. Each EFL was used in 3 groups (n = 20) of extracted teeth, with foramen diameters of 0.27 mm (G27), 0.47 mm (G47), and 0.72 mm (G72). Working length was measured according to manufacturer's instructions and compared with visual measurements (control method). Results were classified as accurate (equal or differences ≤ 0.05 mm) or inaccurate (differences > 0.5 mm). RESULTS: In G27, all EFLs yielded accurate findings (intragroup reliability; Fisher exact test, P < .05), compared with only MiniApex, Root ZXII, and Elements Apex Locator in G47 and G72. MiniApex, Root ZXII, and Elements Apex Locator were similarly accurate regardless of foramen size. iPex and Propex II were the least accurate among the devices tested, and foramen diameter influenced their accuracy, with greater diameters yielding poorer EFL performance. CONCLUSIONS: Foramen diameter did not influence the accuracy of MiniApex, Root ZXII, and Elements Apex Locator EFLs. iPex and Propex II showed decreased accuracy as foramen size increased.

[Residential typologies in Chilean irregular settlements with precarious housing conditions]. / Tipologías residenciales en comunidades chilenas en condiciones de precariedad habitacional.

OBJECTIVE: To identify residential parameters that characterize the physical and social environment in Chile's irregular settlements, and to construct typologies that will allow to develop profiles with those distinctive residential attributes. METHODS: The study examined the universe of irregular settlements (n = 122) in Chile's Metropolitan Region, based on the 2007 national inventory of irregular settlements conducted by the "Un Techo para Chile" foundation. Information about the communities and their locations was obtained from key informants, and these variables were modeled using factor analysis to identify residential parameters, which were then refined by k-means clustering. RESULTS: The factor analysis pointed to three underlying parameters: local social response, the environment beyond the community, and basic services. The key variables shaping these categories were the existence of housing projects, the urban area involved, and access to electricity. The cluster analysis generated four profiles that combined the three parameters: an urban profile with relatively reliable basic services (n = 30), an urban-rural profile with high potential for local social response (n = 32), an urban profile with a high level of environmental threat (n = 43), and a rural profile with low potential for local social response (n = 17). CONCLUSIONS: The residential parameters formed are consistent with the revised theoretical model and suggest relevant indicators for monitoring these communities. Definition of the profiles facilitates assessment of the heterogeneity of residential situations, which helps in the prioritization of areas with deficits or risks that may be present in each cluster. This, in turn, opens the door to further investigation and to exploring opportunities for action.

Tipologías residenciales en comunidades chilenas en condiciones de precariedad habitacional / Residential typologies in Chilean irregular settlements with precarious housing conditions

OBJETIVO: Identificar dimensiones residenciales que caractericen el ambiente físico y social en los campamentos de Chile y construir tipologías que permitan elaborar perfiles con esos atributos residenciales distintivos. MÉTODOS: Se estudió el universo de campamentos (n = 122) de la Región Metropolitana (Chile) a partir del Catastro Nacional de Campamentos realizado por la fundación "Un Techo para Chile" en 2007. Se recolectó información proveniente de informantes clave sobre las comunidades y los lugares de emplazamiento, variables que fueron modeladas empleando un análisis factorial para identificar dimensiones residenciales, las que a su vez fueron refinadas con la técnica de agrupamientos de k-medias. RESULTADOS: El análisis factorial destacó tres dimensiones subyacentes: respuesta social local, ambiente extracomunitario y servicios básicos. Las variables centrales en la formación de esas categorías fueron la existencia de proyectos habitacionales, el área urbana y el acceso a electricidad, respectivamente. El análisis de agrupamientos generó cuatro perfiles que combinaron las tres dimensiones: perfil urbano con baja precariedad de servicios básicos (n = 30), perfil urbano-rural con alto potencial de respuesta social local (n = 32), perfil urbano con alta amenaza ambiental (n = 43) y perfil rural con bajo potencial de respuesta social local (n = 17). CONCLUSIONES: Las dimensiones residenciales formadas son consistentes con el modelo teórico revisado y sugieren indicadores relevantes para el seguimiento de estas comunidades. La identificación de perfiles permite dimensionar la heterogeneidad de realidades residenciales contribuyendo a la priorización de dominios de déficit o riesgos que pueden estar presentes en cada grupo, para con ello profundizar en su investigación y oportunidades de acción.

OBJECTIVE: To identify residential parameters that characterize the physical and social environment in Chile's irregular settlements, and to construct typologies that will allow to develop profiles with those distinctive residential attributes. METHODS: The study examined the universe of irregular settlements (n = 122) in Chile's Metropolitan Region, based on the 2007 national inventory of irregular settlements conducted by the "Un Techo para Chile" foundation. Information about the communities and their locations was obtained from key informants, and these variables were modeled using factor analysis to identify residential parameters, which were then refined by k-means clustering. RESULTS: The factor analysis pointed to three underlying parameters: local social response, the environment beyond the community, and basic services. The key variables shaping these categories were the existence of housing projects, the urban area involved, and access to electricity. The cluster analysis generated four profiles that combined the three parameters: an urban profile with relatively reliable basic services (n = 30), an urban-rural profile with high potential for local social response (n = 32), an urban profile with a high level of environmental threat (n = 43), and a rural profile with low potential for local social response (n = 17). CONCLUSIONS: The residential parameters formed are consistent with the revised theoretical model and suggest relevant indicators for monitoring these communities. Definition of the profiles facilitates assessment of the heterogeneity of residential situations, which helps in the prioritization of areas with deficits or risks that may be present in each cluster. This, in turn, opens the door to further investigation and to exploring opportunities for action.