Prevalence of lower second premolar agenesis and study of rhizolysis of primary second molars without permanent successor with 2 methods

Objectives The aims of this study were to estimate the prevalence of lower second premolar (2Pr) agenesis and to quantify rhizolysis of the preceding primary molars. Materials and methods A descriptive and cross-sectional study was carried out to quantify root resorption of lower primary second mola...

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Detalles Bibliográficos
Autores: García-Navas Fernández de la Puebla, María Lourdes, Caleya Zambrano, Antonia María, Riolobos González, María Fe, Reyes Ortiz, Anabella María, Gallardo López, Nuria Esther
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universidad Alfonso X el Sabio
Repositorio:Repositorio Institucional de la Universidad Alfonso X el Sabio
Idioma:inglés
OAI Identifier:oai:archive.uax.com:20.500.12080/49913
Acceso en línea:https://hdl.handle.net/20.500.12080/49913
Access Level:acceso abierto
Palabra clave:Clinical pediatric dentistry
Infraocclusion
Primary second molar
Root resorption
Second premolar agenesis
Descripción
Sumario:Objectives The aims of this study were to estimate the prevalence of lower second premolar (2Pr) agenesis and to quantify rhizolysis of the preceding primary molars. Materials and methods A descriptive and cross-sectional study was carried out to quantify root resorption of lower primary second molar (p2m) with permanent successor agenesis in panoramic radiographs using 2 methods: Bjerklin¿Bennett method (graphical method by fractions) and ratios¿ method (proportions). Results 3206 panoramic radiographs were reviewed. The final sample consisted of 174 p2m. With the graphical method, it was found that half of the sample had both roots without resorption. With the numerical method, it was observed that root length decreased with age. Almost half of them have infraocclusion and greater infraocclusion led to greater resorption. Healthy p2m showed less resorption. Conclusions The prevalence of 2Pr in the present study was 3.4%. The p2m with agenesis of the successor begin to resorb from the age of 9 years, remaining stable from this age. Those p2m without infraocclusion and healthy suffer less resorption. We consider both methods used to measure root resorption to be valid without the need for multiple sequential radiographs. We consider new studies necessary, expanding the sample and studying more variables that affect rhizolysis.