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While light can affect emotional and cognitive processes of the medial prefrontal cortex (mPFC), no light-encoding was hitherto identified in this region. Here, extracellular recordings in awake mice revealed that over half of studied mPFC neurons showed photosensitivity, that was diminished by inhibition of intrinsically photosensitive retinal ganglion cells (ipRGCs), or of the upstream thalamic perihabenular nucleus (PHb). In 15% of mPFC photosensitive neurons, firing rate changed monotonically along light-intensity steps and gradients. These light-intensity-encoding neurons comprised four types, two enhancing and two suppressing their firing rate with increased light intensity. Similar types were identified in the PHb, where they exhibited shorter latency and increased sensitivity. Light suppressed prelimbic activity but boosted infralimbic activity, mirroring the regions' contrasting roles in fear-conditioning, drug-seeking, and anxiety. We posit that prefrontal photosensitivity represents a substrate of light-susceptible, mPFC-mediated functions, which could be ultimately studied as a therapeutical target in psychiatric and addiction disorders., (© 2024. The Author(s).)

This second part follows on from part 1 published in the previous issue of this journal. The aim of this publication is to offer teams specializing in the primary and secondary treatment of labio-alveolar-palatal clefts a prosthetic evaluation for more rational management of the dental sequellae of clefts for patients who, when they reach adulthood, often wish to improve their facial esthetics, in which the dental element plays an important part. The reorganization and restoration of the maxillary anterior teeth and their esthetic integration with respect to the face and lips would then be less of a problem for plastic surgeons and orthodontists. In this regard, the installation in this sector of implants, following ambitious bone surgery involving the sacrifice of the teeth of the medial nasal process in bilateral forms, is a protocol that could usefully be taken into account., (Copyright © 2014 CEO. All rights reserved.)

The aim of this publication is to offer teams specializing in the primary and secondary treatment of labio-alveolar-palatal clefts a prosthetic evaluation for more rational management of the dental sequellae of clefts for patients who, when they reach adulthood, often wish to improve their facial esthetics, in which the dental element plays a significant part. The reorganization and restoration of the upper anterior teeth, and their esthetic integration with respect to the face and lips, would then be less of a problem for plastic surgeons or orthodontists. In this respect, the installation in this sector of implants, following ambitious bone surgery involving the sacrifice, in bilateral forms, of the teeth of the medial process is a protocol that could usefully be taken into account., (Copyright © 2014 CEO. Published by Elsevier Masson SAS. All rights reserved.)

The survival rates of resin-bonded fixed partial dentures, bonded splints, and bonded combination splints and fixed partial dentures (splints with pontics replacing one or two missing teeth) were determined. For statistical analysis, the splints and splint-prostheses were combined into one group. The average age of all devices combined was 5.7 years. Eleven of 145 resin-bonded fixed partial dentures failed; the survival rate was 83.0%. There was no statistically significant difference between the survival rates of prostheses, whether bonded to prepared teeth or unprepared teeth. Fifteen of 98 splints and splint-prostheses failed. The survival rate of splints and splint-prostheses bonded to prepared teeth (71.6%) was higher than that of splints and splint-prostheses bonded to unprepared teeth (53.6%). To determine the continuing relevance of resin-bonded prostheses, the number of instances in which implant dentures could have been used was calculated. Implant treatment would have been possible in only 14 or 98 cases.

Developments in biomaterials in the field of adhesion have made possible a less invasive dentistry. Improvements in adhesive polymers along with the analysis of certain failures in resin-bonded prostheses have suggested the micropreparation of abutment teeth. A long-term study of resin-bonded prostheses and splints was undertaken. The success rate of this protocol is presented for a study period of 10 years (1984 to 1993). These results indicated that the resin-bonded prosthesis is a viable option in patients who are missing one or two teeth. Of 145 prostheses, 11 failed, resulting in an overall survival rate of 83% (Kaplan-Meier test). Furthermore, the study confirmed that, for splints, preparation is important to counter the major stresses related to tooth mobility in patients with periodontal disease.

The advent of osseointegrated implants has considerably influenced the treatment of the edentulism. The Brånemark's protocol allows a high enough degree of predictability for a wide variety of clinical applications. A selection of the most typical indications attempts to focus on the benefit of implant supported prosthesis, regarding the conventional prosthetic treatment. The relative indications concern single-tooth replacement and Kennedy class III situations where classical tooth supported bridge is not easily feasible. The resort to osseointegration treatment enhances the possibilities of prosthetic rehabilitation in unfavorable conditions. The greater part of the indications is represented by Kennedy class I and class II situations. Clinical examples selected show the different combinations related to the fixtures position in the maxilla where bone availability is reduced. When just one fixture can be installed, connection with adjacent tooth must be carefully indicated. With two fixtures, a bridge must be designed with a posterior cantilever. But the opposite dentition can also dictate a fixture installation in the posterior region for a good occlusal stabilization: a specific modality of fixture installation in the pterygoid region has provided a seductive alternative. The last part concerns the prosthetic rehabilitation of advanced cases involving evolutive periodontal disease. The current trends determine a flexible approach with strategic extractions and progressive fixtures installation during stabilized periods of the disease activity. This management of the treatment planning reduces the psychogenic stress related to the complete edentulism and allows a easier transition from partial implant supported-prosthesis to fully bone anchored-prosthesis.