Contemporary Cleaning and Shaping of the Root Canal System.

Prevention or treatment of apical periodontitis is aimed at disinfecting the root canal system so that the periradicular tissues are not vulnerable to attack from microbiota within the tooth. This is achieved by a process of cleaning and shaping the root canal space. The fundamental principles underlying this process have not changed in decades.

Visual object agnosia is associated with a breakdown of object-selective responses in the lateral occipital cortex.

Patients with visual object agnosia fail to recognize the identity of visually presented objects despite preserved semantic knowledge. Object agnosia may result from damage to visual cortex lying close to or overlapping with the lateral occipital complex (LOC), a brain region that exhibits selectivity to the shape of visually presented objects. Despite this anatomical overlap the relationship between shape processing in the LOC and shape representations in object agnosia is unknown.

Regenerative endodontics: regeneration or repair?

Recent advances in biotechnology and translational research have made it possible to provide treatment modalities that protect the vital pulp, allow manipulation of reactionary and reparative dentinogenesis, and, more recently, permit revascularization of an infected root canal space. These approaches are referred to as regenerative procedures. The method currently used to determine the origin of the tissue secreted during the repair/regeneration process is largely based on the identification of cellular markers (usually proteins) left by cells that were responsible for this tissue production.

When the brain remembers, but the patient doesn't: converging fMRI and EEG evidence for covert recognition in a case of prosopagnosia.

The role of the occipito-temporal cortex in visual awareness remains an open question and with respect to faces in particular, it is unclear to what extent the fusiform face area (FFA) may be involved in conscious identification. An answer may be gleaned from prosopagnosia, a disorder in which familiar faces are no longer recognized. This impairment has sometimes been reported to be associated with implicit processing of facial identity, although the neural substrates responsible for unconscious processing remain unknown.

Neural response to the behaviorally relevant absence of anticipated outcomes and the presentation of potentially harmful stimuli: A human fMRI study.

Adaptive behavior requires the ability to react to potentially harmful stimuli, characterized by high negative inherent emotional salience (iES) (e.g., spiders, snakes), and to the unexpected non-occurrence of anticipated events.

Seeing the phantom: a functional magnetic resonance imaging study of a supernumerary phantom limb.

Objective: Supernumerary phantom limb (SPL) is a rare neurological manifestation where patients with a severe stroke-induced sensorimotor deficit experience the illusory presence of an extra limb that duplicates a real one. The illusion is most often experienced as a somesthetic phantom, but rarer SPLs may be intentionally triggered or seen. Here, we report the case of a left visual, tactile, and intentional SPL caused by right subcortical damage in a nondeluded woman.

Spatial attention and memory versus motor preparation: premotor cortex involvement as revealed by fMRI.

Recent studies in both monkeys and humans indicate that the dorsal premotor cortex participates in spatial attention and working memory, in addition to its well known role in movement planning and execution. One important question is whether these functions overlap or are segregated within this frontal area. Single-cell recordings in monkeys suggest a relative specialization of the rostral portion of dorsal premotor cortex for attention and/or memory and of the caudal region for motor preparation.