Accidental injury of the inferior alveolar nerve due to the extrusion of calcium hydroxide in endodontic treatment: a case report

During clinical endodontic treatment, we often find radiopaque filling material beyond the root apex. Accidental extrusion of calcium hydroxide could cause the injury of inferior alveolar nerve, such as paresthesia or continuous inflammatory response. This case report presents the extrusion of calcium hydroxide and treatment procedures including surgical intervention. A 48 yr old female patient experienced Calcipex II extrusion in to the inferior alveolar canal on left mandibular area during endodontic treatment. After completion of endodontic treatment on left mandibular first molar, surgical intervention was planned under general anesthesia. After cortical bone osteotomy and debridement, neuroma resection and neurorrhaphy was performed, and prognosis was observed. But no improvement in sensory nerve was seen following surgical intervention after 20 mon. A clinician should be aware of extrusion of intracanal medicaments and the possibility of damage on inferior alveolar canal. Injectable type of calcium hydroxide should be applied with care for preventing nerve injury. The alternative delivery method such as lentulo spiral was suggested on the posterior mandibular molar.

Research advance in neurotoxicity of quantum dots / 中国药理学与毒理学杂志

As quantum dots( QDs),an advanced porduct of nanotechnology,have been widely used in bio-medicine due to their unique photoelectric properties. QD safety evaluation has become a hot area of research. So far,some researchers have expressed concern about the neurotoxic potential of QDs because the central nervous system was confirmed to be one of the target organs. Several studies found that QDs could enter the central nervous system by crossing the blood brain barrier and following neural pathways and produce some neurotoxic effects,such as damaging the structure and function of neural cells and impairing synaptic plasticity. The potential toxicity mechanisms could include oxidative stress,inflammation and change of ion channels.

Usefulness of Color Vision Test for Early Detection of Neurological Damages by Neurotoxic Substances / 예방의학회지

This paper reviews the published literature that is concerned with color vision impairment from industrial and environmental exposure to neurotoxic substances, and we evaluated whether testing for color vision impairment could be an affordable procedure for assessing these neurotoxic effects. In general, most cases of congenital color vision impairment are red-green, and blue-yellow impairment is extremely rare. However, most of the acquired color vision impairment that is related to age, alcohol or environmental factors is blue-yellow impairment. Therefore, many studies have been performed to identify this relationship between exposure to neurotoxic substances, such as organic solvents and heavy metals, and the prevalence of blueyellow color vision impairment. The test for color vision impairment is known to be very sensitive to the early signs of nervous system dysfunction and this can be useful for making the early diagnosis of neurotoxic effects from exposure to very low concentrations of toxic substances.

The Neurotoxic Effects of Artemether on the Cytoarchitecture of the Trapezoid Nuclei of Adult Male Wistar Rats (Rattus novegicus) / Efectos Neurotóxicos del Artemeter sobre la Citoarquitectura del Núcleo Trapezoide en Ratas Machos Adultas Wistar (Rattus novegicus)

In Man, artemether is given at 160mg/kg/bodyweight for three days in the treatment of malarial. This study investigated the effects of corresponding 1.23/mg/kg/bodyweight of artemether for a period of seven days on the trapezoid nuclei and the behavioural functions on day 7 after drug administration in rats. This study observed no gross or morphological differences between the two groups of animals (control and experimental groups) on day 7 at the completion of experimental procedure. A significant statistical increase in average body weight was observed in the control groups C1 (which received only standard diet and water) and C2 (which received 1.23mg/kg/bodyweight of normal saline intramuscularly in addition to standard diet and water) from 140- + 19.65g on day 1 to 146 + 19.90g on Day 1 and 151 + 12.0g on Day 1 to 156.2 + 12.2g on Day 7 respectively. There was a non-statistically significant apparent reduction in body weight in the experimental group E, (which received intramuscular injection of 1.23mg/kg/bodyweight of artemether) from 160 + 9.0g on Day 1 to 157.4 + 8.0g on Day 7. The assessment of brainstem nuclei showed patchychromatic appearance of neurons of the trapezoid nuclei in the experimental group as against the normal vesicular appearance of neurons of the trapezoid nuclei in the Control Group C. The rats in the control groups CI and C2 displayed normal balance and co-ordination, while rats in the experimental group E, showed abnormalities of balance and co-ordination. Using t-test analysis technique at 95% confidence interval i.e t < 0.05 and P - value = 2.26, no significant difference was observed between the average brain weight in the control groups C1 and C2 and the experimental group E.

En el Hombre, el artemeter es dado en el tratamiento de la malaria en dosis de 160 mg/kg de peso, por tres días. Este estudio abordó los efectos de un tratamiento con artemeter, durante 7 días (en dosis de 1,23 mg/kg de peso) sobre el núcleo trapezoide de ratas y las funciones de conducta, en el día 7 después de la administración de la droga. No se observaron ni macro ni diferencias morfológicas entre dos grupos de animales (grupos control y experimental) en el día 7 de la completación del procedimiento. Un incremento estadísticamente significativo en el promedio del peso del cuerpo fue encontrado en el grupo control C1 (el que recibió solamente una dieta standard y agua) y C2 (que recibió 1,23 mg/kg de peso de solución salina intramuscular agregada a la dieta y al agua) que fue desde 140± 19,65 g y 146 ± 19,9 g en el día 1, respectivamente y de 151 ± 12 g y de 156,2 ± 12,2 g en el día 7, respectivamente. No hubo una reducción aparente estadísticamente significativa en el peso del cuerpo del grupo experimental (el cual recibió inyección intramuscular de 1,23 mg/kg de peso de artemeter), la que fue desde 160 ± 9 g en el día 1 y de 157,4 ± 8, en el día 7. La evaluación de núcleos del tronco encefálico mostró apariencia cromática irregular de las neuronas del núcleo trapezoide en el grupo experimental contrariamente a la apariencia vesicular normal de las neuronas de este núcleo en el grupo control. Las ratas de los grupos controles C1 y C2 presentaron un normal balanceo y coordinación, mientras que las ratas del grupo experimental, mostraron anormalidades de balanceo y coordinación. Usando el test t con 95% de intervalo de confianza, p 0,05 y con un valor p=2,26, no se observaron diferencias estadísticamente significativas entre el promedio de los grupos C1 y C2 y del grupo experimental.