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Concept: Tooth


The restoration of dentine lost in deep caries lesions in teeth is a routine and common treatment that involves the use of inorganic cements based on calcium or silicon-based mineral aggregates. Such cements remain in the tooth and fail to degrade and thus normal mineral volume is never completely restored. Here we describe a novel, biological approach to dentine restoration that stimulates the natural formation of reparative dentine via the mobilisation of resident stem cells in the tooth pulp. Biodegradable, clinically-approved collagen sponges are used to deliver low doses of small molecule glycogen synthase kinase (GSK-3) antagonists that promote the natural processes of reparative dentine formation to completely restore dentine. Since the carrier sponge is degraded over time, dentine replaces the degraded sponge leading to a complete, effective natural repair. This simple, rapid natural tooth repair process could thus potentially provide a new approach to clinical tooth restoration.

Concepts: Enzyme, Animal, Teeth, Tooth, Dental caries, Portland cement, GSK-3, GSK3B


BACKGROUND: Recent studies reported on the very complex morphology of the pulp system in equine cheek teeth. The continuous production of secondary dentine leads to distinct age-related changes of the endodontic cavity. Detailed anatomical knowledge of the dental cavities in all ages is required to explain the aetiopathology of typical equine endodontic diseases. Furthermore, data on mandibular and maxillary pulp systems is in high demand to provide a basis for the development of endodontic therapies. However, until now examination of the pulp cavity has been based on either sectioned teeth or clinical computed tomography. More precise results were expected by using micro-computed tomography with a resolution of about 0.1 mm and three-dimensional reconstructions based on previous greyscale analyses and histological verification. The aim of the present study was to describe the physiological configurations of the pulp system within a wide spectrum of tooth ages. RESULTS: Maxillary teeth: All morphological constituents of the endodontic cavity were present in teeth between 4 and 16 years: Triadan 06s displayed six pulp horns and five root canals, Triadan 07-10s five pulp horns and four root canals and Triadan 11s seven pulp horns and four to six root canals. A common pulp chamber was most frequent in teeth <=5 years, but was found even in a tooth of 9 years. A large variety of pulp configurations was observed within 2.5 and 16 years post eruption, but most commonly a separation into mesial and distal pulp compartments was seen. Maxillary cheek teeth showed up to four separate pulp compartments but the frequency of two, three and four pulp compartments was not related to tooth age (P > 0.05). In Triadan 06s, pulp horn 6 was always connected to pulp horns 1 and 3 and root canal I. In Triadan 11s, pulp horns 7 and 8 were present in variable constitutions. Mandibular teeth: A common pulp chamber was present in teeth up to 15 years, but most commonly seen in teeth <=5 years. A segmented pulp system was found in 72% of the investigated teeth. Segmentation into separate mesial and distal pulp compartments was most commonly present. Pulp horn 4 coalesced either with the mesial pulp horns 1 and 3 or with the distal pulp horns 2 and 5. CONCLUSIONS: Details of the pulpar anatomy of equine cheek teeth are provided, supporting the continuous advancement in endodontic therapy. Numerous individual configurations of the pulp system were obtained in maxillary cheek teeth, but much less variability was seen in mandibular cheek teeth.

Concepts: Teeth, Tooth, Dental caries, Root canal, Endodontic therapy, Endodontics, Dentin, Animal anatomy


Rhabdodontidae is a successful clade of ornithopod dinosaurs, characteristic of Late Cretaceous continental faunas in Europe. A new rhabdodontid from the late Campanian, of southern France, Matheronodon provincialis gen. et sp. nov., is characterized by the extreme enlargement of both its maxillary and dentary teeth, correlated to a drastic reduction in the number of maxillary teeth (4 per generation in MMS/VBN-02-102). The interalveolar septa on the maxilla are alternately present or resorbed ventrally so as to be able to lodge such enlarged teeth. The rhabdodontid dentition and masticatory apparatus were adapted for producing a strict and powerful shearing action, resembling a pair of scissors. With their relatively simple dentition, contrasting with the sophisticated dental batteries in contemporary hadrosaurids, Matheronodon and other rhabdodontids are tentatively interpreted as specialized consumers of tough plant parts rich in sclerenchyma fibers, such as Sabalites and Pandanites.

Concepts: Teeth, Tooth, Cretaceous, Dinosaur, Ornithopod, Rhabdodontidae, Late Cretaceous, Campanian


Objectives: The aim of this investigation was to present and evaluate an original method of mini-invasive oral surgery and orthodontics based on 3D images from a computed tomography software (3DNEO(®), 3DNEOVISION). Materials and methods: Three patients with impacted teeth were examined and their data were analyzed with this software based on the “region growing” method. Results: Several clinical interests emerge : locate and visualize precisely the relationships of the impacted tooth with the adjacent anatomical elements under the desired angle, associate/dissociate the different elements of the 3D scene, measure the distances, calculate the axes of traction, materialize the way of traction and the optimal point for bonding, prepare virtually the surgical exposure and orthodontic treatment plan. Conclusion: This 3D method might provide information for improved diagnosis and treatment plans in order to ultimately result in more successful treatment outcomes and better care for patients.

Concepts: Surgery, Medical imaging, Physician, Tooth, Dentistry, Orthodontics, Plan, Dentistry branches


The goal of this study was to examine the adhesive interface of pulp tissue to investigate subclinical failures after direct pulp capping (DPC) of human teeth by using a dentin adhesive system.

Concepts: Teeth, Tooth, Dentin, Pulp, Odontoblast


The authors compared the local anesthetic efficacy and safety of an intranasally administered formulation of tetracaine and oxymetazoline (K305) with placebo in adult participants undergoing single dental restorative procedures in teeth nos. 4 through 13.

Concepts: Anesthesia, Local anesthesia, Placebo, Teeth, Tooth, Topical anesthetic, Local anesthetic


Restorative procedures are accompanied by a reduction of tooth stability, a decrease of fracture resistance, and an increase in deflection of weakened cusps. The choice between a direct or an indirect restorative technique, mainly in posterior areas, is a challenge, and involves biomechanical, anatomical, functional, esthetic, and financial considerations. In this article, the pros and cons of direct restorations are examined, as well as an analysis of indirect restorations and an overview of dental ceramics. In particular, several clinical uses of lithium disilicate overlays with a circumferential adhesive ferrule effect are proposed: heavily compromised vital teeth with thin walls, cracked teeth, and endodontically treated molars. Clinical procedures are described step by step on the basis of data from scientific literature. In conclusion, the use of lithium disilicate in combination with adhesive technologies can lead to a more conservative, economic, and esthetic approach in the restoration of heavily compromised teeth.

Concepts: Science, Teeth, Tooth, Lithium, Chess, Lithium pharmacology, Ceramic, Dental restoration


The purpose of this study was to develop and validate a gas chromatography-mass spectrometry method to detect drugs of abuse in a single sample of tooth. Pulverized samples of dental materials were subjected to acid hydrolysis to detect opiates, cocaine and their metabolites. The residual dental materials from these analyses were subjected to basic extraction to detect cannabis products (Δ(9)-tetrahydrocannabinol, cannabidiol and cannabinol). The method showed a good linearity between 0.05 and 2 ng/mg for all substances. The limit of detection ranged from 0.02 to 0.03 ng/mg, and the limit of quantification was 0.05 ng/mg. The application of the method to samples of teeth obtained from drug addicts was successful. It can be applied in post-mortem cases, especially when limited amounts of sample are available.

Concepts: Analytical chemistry, Morphine, Drug addiction, Addiction, Teeth, Tooth, Psychoactive drug, Substance abuse


Oral diseases are a health problem worldwide. Differences in oral health status may vary with geographical locations, but also within the same country and between groups with different social backgrounds. The specific aims were to describe secular trends in oral health status regarding number of remaining teeth and also to describe differences in socio-economic status, among 38- and 50-year-old women, over a 36-year period.

Concepts: Epidemiology, Socioeconomic status, Sociology, Teeth, Tooth, Social status


The dental morphology and tooth replacement pattern of Liaoceratops yanzigouensis, the earliest known neoceratopsian, are important for our understanding of the evolution of the ceratopsian dental system. Here we describe the dental morphology and tooth replacement of Liaoceratops yanzigouensis based on high-resolution computed tomographic (CT) scan data of three specimens including the holotype, the first study for basal ceratopsian. The three-dimensional reconstructions reveal some important new information, including: three teeth in the premaxilla in one side, two more teeth in the dentary than in the maxilla, incipiently developed mesial grooves on some crowns, two generations of replacement teeth within some tooth families; and most functional teeth were under heavy resorption by the replacement process, but still remained functional. Comparisons of tooth pair positions from opposite sides in the four jaw quadrants of three specimens revealed a degree of bilateral symmetry in replacement pattern. Reconstruction of Zahnreihen yields an avergae z-spacing of 2.58 with simultaneous front-to-back tooth replacement. Our study presents the earliest evidence of derived neoceratopsian traits of the complex dental batteries in ceratopsids. Most significantly, our models reveal the tracts of partially resorbed functional teeth which appears to track the growth of the jaws, traits previously undocumented in Ceratopsia.

Concepts: Mandible, Teeth, Tooth, Maxilla, Ceratopsia, Ceratopsians, Liaoceratops, Xu Xing