Radiolucência intracoronal pré-eruptiva (PECR) de um segundo molar permanente. relato de caso / Pre-eruptive intracoronal radiolucency (PECR) of a permanent second molar. case report

Introdução: A Radiolucência intracoronal pré eruptiva (PECR) é um achado radiográfico, com aspecto de lesão radiolúcida na dentina coronária, adjacente a junção amelodentinária, em dentes não irrompidos. Objetivo: Relatar um caso de possível reabsorção intracoronal pré-eruptiva com destruição extensa de dentina e envolvimento pulpar de um segundo molar permanente recém-erupcionado. Método: Após definição do diagnóstico, optou-se por um tratamento conservador, com a realização de capeamento pulpar direto com a finalidade de manutenção da vitalidade pulpar e término de formação das raízes. Resultado: Após o tratamento, paciente permaneceu assintomática no controle de quinze dias, com teste de vitalidade normal e sem sinais de inflamação. Conclusão: A interpretação cuidadosa do exame radiográfico é crucial para a detecção precoce e manejo adequado dessas lesões.

Pre-eruptive intracoronal radiolucency (PECR) is a radiographic finding, with the appearance of a radiolucent lesion in the coronary dentin, adjacent to the dentinal-enamel junction, in unerupted teeth. Objective: To report a case of possible pre-eruptive intracoronal resorption with extensive dentin destruction and pulpal involvement of a newly erupted second permanent molar. Method: After defining the diagnosis, a conservative treatment was chosen, with direct pulp capping in order to maintain pulp vitality and end root formation. Result: After treatment, the patient remained asymptomatic in the fifteen-day control, with normal vitality test and no signs of inflammation. Conclusion: Careful interpretation of the radiographic examination is crucial for early detection and proper management of these lesions.

La exposición prenatal a fluoruro induce cambios en la porción coronal de la cripta ósea y altera la erupción dental en crías lactantes / Prenatal fluoride exposure induces changes in the coronal portion of bony crypt and alters dental eruption in suckling rats

La erupción dental es un proceso estrictamente regulado y programado espacial y temporalmente. El objetivo del trabajo fue estudiar el efecto de la exposición prenatal a fluoruro de sodio (NaF) sobre los eventos morfológicos y celulares que ocurren en el hueso supracoronal del primer molar de crías de rata durante la etapa preeruptiva. Se emplearon crías (n=6-8 por grupo) provenientes de madres que bebieron crónicamente agua con diferentes concentraciones de F- en forma de NaF durante la gestación y lactancia: control y NaF (50 mg/L). En cortes histológicos de la mandíbula de crías de 3 y 10 días se analizaron parámetros de histomorfometría estática en la zona supracoronal de la canastilla ósea a la altura del primer molar inferior: volumen óseo trabecular [BV/TV (%)], número de osteoclastos por milímetro (N.Oc/mm) y las variables indirectas: número de trabéculas [Tb.N (1/mm)], espesor [Tb.Th (µm)] y separación trabecular [Tb.Sp (µm)]. En crías de 15 días se midió el grado de erupción [TED (µm)] del primer molar inferior. Los resultados se analizaron con el test "t" de Student considerando diferencias significativas a p<0,05. El análisis histomorfométrico demostró un incremento en el BV/TV (%) del hueso supracoronal (p<0,01) asociado con disminución del N.Oc/mm (p<0,01) en crías de 3 y 10 días expuestas prenatalmente al F-. El grado de erupción dental fue menor en animales expuestos prenatalmente al F- en comparación con los controles (p<0,01). En conclusión, los resultados observados en la mandíbula de crías expuestas durante la etapa prenatal y posnatal temprana al F- sugieren un efecto disruptivo sobre la actividad resortiva necesaria para formación del canal eruptivo. (AU)

Tooth eruption is a tightly regulated and spatially and temporally programmed process. The aim of this study was to examine the effect of prenatal NaF exposure on the morphological and cellular events that occur in the supracoronal area of bony crypt of the first rat molar during the preeruptive stage. Offspring from two groups of rats were used (6-8 per group): Control and 50 mg/L NaF. The treatment was performed during pregnancy and lactation. Suckling pups were euthanized at 3-, 10- and 15-days-old by cervical dislocation. Mandibles were removed and histologically processed to obtain buccolingual sections stained with H&E. In sections of first mandibular molar of 3- and 10-days-old pups, the following static histomorphometric parameters were evaluated: trabecular bone volume [BV/TV (%)] and number of osteoclasts (N.Oc/mm). Also, indirect parameters were obtained: trabecular number [Tb.N (1/mm)], trabecular thickness [Tb.Th (µm)], and trabecular separation [Tb.Sp (µm)]. The degree of tooth eruption [TED (µm)] was determined. Results are expressed as mean ± SE and analyzed by Student t-test. Histomorphometric analysis showed an increase in the BV/TV (%) of the bone crypt of 3- and 10- days-old pups exposed to NaF (p <0.01); this increase was associated with a decrease in the N.Oc/mm (p <0.01). TED of mandibular first molar was lower in prenatal NaF exposed group than in control group (p<0.01). In conclusion, the increased BV/TV and the lower N.Oc observed in the bone crypt of 3- and 10- days-old pups from mothers treated with NaF suggested a disruptive effect triggered by F- on the formation events of the eruptive pathway in the offspring. (AU)

Relationship between Pre-Eruptive Buccal Pit Radiolucency and Restoration in Mandibular First Molar / 대한소아치과학회지

Pre-eruptive intracoronal resorption (PEIR) is a developmental defect in the crown of a pre-eruptive tooth. The purpose of this study was to investigate the relationship between the size of the pre-eruptive buccal pit radiolucency, which is suspected as PEIR on a panoramic radiography, and the need for restoration after the eruption of a mandibular first molar.The experimental group included 35 mandibular first molars, in which lesions requiring definite restoration were observed during eruption. The control group consisted of 64 sound mandibular first molars after eruption. The sex, age, tooth position, tooth formation stage, size of the pre-eruptive buccal pit radiolucency, and restoration methods in the experimental group and control group were examined.Compared with the control group, the experimental group showed a statistically significant difference in the size of the buccal pit before eruption. The buccal pit size for predicting the need for restoration was further examined by receiver operating characteristic curve analyses, and the area under the curve was 0.813 ± 0.047.If radiolucency is observed at the buccal pit of the mandibular first molar before eruption, periodic observations and post-eruption examinations are required.