Bücher und Digitale Medien

Purpose: To evaluate the fracture strength of endodontically treated molars filled with different composite resins, with or without fiber reinforcement. Materials and methods: A total of 60 intact mandibular molars were selected and endodontically treated. A standardized mesio-occlusal-distal cavity was prepared with cervical margins 1 mm above the cementoenamel junction and oral and buccal walls with 1.5-mm remaining thickness. Universal adhesive was used in all specimens in etch-and-rinse mode. Specimens were divided into four groups (n = 15 each) according to restoration technique: CSM group, adhesive overlay with hybrid ceramic (CeraSmart, GC); EXP group, direct composite restoration (Essentia U, GC) and everX Posterior (GC) as core material; ESU group, direct composite restoration (Essentia U); and EST group, direct composite restoration (Essentia U) reinforced with horizontal bidirectional glass fibers placed over the pulpal chamber floor (everStick-Net, GC). After 7 days of water storage, samples were loaded until fracture using a universal testing machine. The maximum breaking loads were recorded in Newtons (N), and statistical analysis was then conducted with two-way analysis of variance and post hoc Tukey test. Fragments were analyzed using scanning electron microscopy. Results: Mean fracture resistance was: CSM = 1,428.9 ± 316.90 N; EXP = 1,874.57 ± 299.47; ESU = 1,557.44 ± 355.65; and EST = 1,870.27 ± 145.11. CSM and EXP showed the highest strength values when compared to the other groups. The variable "fiber insertion" did not significantly alter the fracture resistance. Origins of the fractures were always located on the occlusal surface, mainly from the major contact loading area. Conclusion: The use of everX Posterior showed great improvement in fracture resistance, similar to cuspal coverage restoration. However, only short fiber-reinforced composite resins showed a favorable fracture pattern.

Die Anzahl der im zahnärztlichen Bereich verfügbaren Technologien wächst jedes Jahr weiter, wodurch nun vollständig digitale Abläufe möglich sind, die vorhersehbare ästhetische und funktionelle Ergebnisse liefern können. Dieser klinische Bericht dokumentiert schrittweise eine umfassende Mundrehabilitation, die mit einem vollständig digitalen Ansatz und einer adhäsiven und präparationsfreien Methode geplant und durchgeführt wurde. Nachdem wir die Bedürfnisse des Patienten bewertet hatten, erstellten wir einen Behandlungsplan, der die funktionellen und ästhetischen Wünsche des Patienten berücksichtigte. Die Überlagerung von 2D-Bildern und 3D-Modellen sowie Gesichtsscans des Patienten ermöglichte die digitale Vorschau des ästhetischen Ergebnisses durch die Anwendung des "Copy-Paste"-Ansatzes zur Wiederherstellung des oberen vorderen Sextanten.

Purpose: To evaluate the fracture strength of endodontically treated molars filled with different composite resins with vs without fiber reinforcement. Materials and Methods: A total of 60 intact mandibular molars were selected and endodontically treated. A standardized mesio-occlusal-distal cavity was prepared with cervical margins 1 mm above the cementoenamel junction and oral and buccal walls with 1.5-mm thickness. Universal adhesive was used in all specimens in etch-and-rinse mode. Specimens were divided into four groups (n = 15 each) according to restoration technique: group CSM = adhesive overlay with hybrid ceramic; group EXP = direct restoration with short fiber–reinforced composite; group ESU = direct restoration with nanohybrid composite; and group EST = direct restoration with nanohybrid composite reinforced with horizontal bidirectional glass fibers placed over the pulpal chamber floor. After 7 days of storage in water, samples were loaded until fracture using a universal testing machine. The maximum breaking loads were recorded in Newtons, and statistical analysis was then conducted with two-way ANOVA and post hoc Tukey test. Fragments were analyzed using scanning electron microscopy. Results: Mean fracture resistance values were: CSM = 1,428.91 ± 316.90 N; EXP = 1,874.57 ± 299.47 N; ESU = 1,557.44 ± 355.65 N; and EST = 1,870.27 ± 145.11 N. The CSM and EXP groups showed the highest strength values when compared to the other groups. The variable fiber insertion did not significantly alter the fracture resistance. The origin of the fracture was always located on the occlusal surface, mainly in the major contact loading area. Conclusion: The use of fiber-reinforced composite showed great improvement in fracture resistance, similar to a cuspal coverage restoration. However, only short fiber–reinforced composites showed a favorable fracture pattern. Int J Prosthodont 2023;36:603–611

Objectives: To review the dynamic analytical elements used in the functional assessment of the stomatognathic system, summarize the available scientific evidence, and consider interrelations with body posture and cognition. Method and materials: A thorough literature search was conducted using PubMed, the Cochrane Library database, and Google Scholar. Peer-reviewed articles and literature reviews provided up-to-date information addressing three topics: (a) the available knowledge and recent evidence on the relationship between the morphologic aspects of dental/craniofacial anatomy and oral function/dysfunction, (b) mandibular dynamics, considering mobility, functional activity, and existing methodologies of analysis, and (c) a possible correlation between the stomatognathic system, body posture, and cognition. Results: Modern dentistry may be regarded as a human adaptation strategy, helping to conserve healthy teeth for much longer without risking overall health. It is futile to treat patients using a mechanistic, sectorial approach that misrepresents patient behavior and requests, just as it is to affirm the absence of any structure-function relationships. However, it is also evident that there is a lack of general consensus on the precise functional assessment of the stomatognathic system, mostly due to the methodologic heterogeneity employed and the high risk of bias. Despite the abundant evidence produced with the aim of providing solid arguments to define dynamic models of functional assessment of the stomatognathic system, it is yet to become highly empirical, based as it is on operator experience in daily clinical practice. Conclusions: Further efforts from the scientific and clinical community, with the help of progress in technology, remain should this gap be filled and should substantial data on differences between pathologic and physiologic dynamic models of function be provided. Dentistry needs to employ – on a larger scale – objective, dynamic methods of analysis for the functional evaluation of the stomatognathic system, embracing concepts of “personalized medicine” and “interprofessional collaborations.” Schlagwörter: cognition, kinesiography, mastication, neuroplasticity, oral function, posture

Objectives: To review the elements of static analysis in the functional assessment of the stomatognathic system, as promoted for more than a century by gnathologists, and summarize the available scientific evidence, including anthropologic observations. Method and materials: A thorough search was conducted using PubMed, the Cochrane Library database, and Google Scholar. From peer-reviewed articles and other scientific literature, up-to-date information addressing three topics was identified: (a) the anthropologic perspective with particular consideration for the role of progressive dental wear over time, (b) descriptions of gnathologic principles and evidence on their scientific validity, and (c) the methodologic inaccuracies introduced by seeking to correlate variables directly rather than allowing for causal inference. Results: For decades gnathology attempted to describe a structure-function correlation within the stomatognathic system by means of a model whose principles were static and mechanistic references. No scientific validation was ever achieved, placing clinical and research consensus out of reach. Conclusions: A historical perspective helps to place the fundamentals of gnathology into context: They were conceived to solve technical difficulties but were then assumed to be physiologic stereotypes. This misconception led to a decades-long promotion of mechanistic theories to describe oral function, but the evidence available today supports a more flexible and adaptable approach. Gnathologic arguments have been relegated to become exclusively of technical relevance in oral rehabilitation. Schlagwörter: dental occlusion, gnathology, oral function, real-world data, temporomandibular disorder, tooth wear

Die Entwicklung der digitalen Technik verändert die Zahnmedizin in zunehmendem Maß. Weil die CAD/ CAM-Systeme und dentalen Werkstoffe kontinuierlich verbessert werden, sind Behandlungspläne für Rehabilitationen mittlerweile mit vollständig digitalen und nicht invasiven Ansätzen ausführbar. Digitale Ressourcen erhöhen die Genauigkeit bei der Vorhersage des ästhetischen und funktionellen Behandlungsergebnisses. Inzwischen finden sich immer mehr Patienten, die von starker Zahnabnutzung betroffen sind und von solchen Behandlungskonzepten profitieren können. Der vorliegende Beitrag bietet die Schritt- für-Schritt- Dokumentation einer Gesamtrehabilitation, die im digitalen Workflow mit additiven CAD/CAM-Restaurationen aus Komposit realisiert wurde. Zudem wird eine innovative Form der Funktionsanalyse gezeigt und diskutiert. Die Ausgangssituation wurde analysiert und mithilfe einer Snap-on-Apparatur mit der Rehabilitationsplanung verglichen. Nach der intraoralen Anpassung und Bestätigung wurde die definitive Versorgung realisiert. Die am Provisorium gewonnenen Erkenntnisse wurden hierfür digital an das Labor übermittelt.

Ein modernes Behandlungskonzept für Zahnabnutzung zielt darauf ab, die Progression frühzeitig aufzuhalten und idealerweise Präventivmaßnahmen einzuleiten. Falls es hierfür jedoch schon zu spät ist, kann mit interzeptiven Maßnahmen eingegriffen werden. Wichtig ist, die Notwendigkeit einer prothetischen Gesamtbehandlung zu vermeiden, da sie einen weiteren Hartsubstanzverlust mit entsprechenden biologischen Folgen bedingt. Da sich Anzeichen von Zahnabnutzung häufig bereits bei jungen Patienten finden, kann mithilfe der interzeptiven Behandlung mit Non-prep-Kompositrestaurationen die Progression des Hartsubstanzverlusts frühzeitig aufgehalten werden. Da die Zahnabnutzung normalerweise ein lebenslanges Problem ist, hat dieser Ansatz entscheidende zusätzliche Vorteile, da er erschwinglich und das Ergebnis relativ unproblematisch zu erhalten ist. Unter Wiederherstellungsoptionen für abgenutzte Zähne mit Komposit sind in letzter Zeit In-situ-Schablonentechniken (für Einzelzähne oder den ganzen Kiefer) wegen ihrer Effizienz und Einfachheit immer interessanter geworden. In diesem Artikel werden Modifikationen der ursprünglichen "Full-Molding-Technik" vorgestellt, mit deren Hilfe die meisten bisherigen Unzulänglichkeiten dieser Technik überwindbar sind. Dazu gehören die Verformung der Schablone, zeitraubende Überschussentfernung in den Approximalbereichen und unzureichende Präzision bei der Reproduktion der okklusalen Anatomie. Die 1- und 3-Jahres-Nachkontrollen beider hier gezeigten Fälle bestätigen die funktionelle und ästhetische Qualität der mit dieser Technik erreichten Resultate. Überlagerungen der kinesiografischen Analysen und 3-D-Abformungen der Situationen unmittelbar sowie ein Jahr nach der Behandlung für einen der beiden Fälle zeigen das Potenzial der Behandlungsmethode genauer auf.

The proliferation of digital technology is progressively changing dentistry. Thanks to continual improvements in CAD/CAM devices and dental materials, it is possible nowadays to carry out a treatment plan for oral rehabilitations with fully digital approaches and noninvasive concepts. The availability of digital resources allows clinicians to increase the predictability of enhanced esthetics and good functional results. There is an increasing number of patients today who are affected by excessive tooth wear and may benefit from these kinds of treatments. This article provides a step-by-step documentation of a full-mouth rehabilitation performed with a digital approach and additive CAD/CAM composite resin restorations. An innovative functional evaluation is also documented and discussed. The initial situation was assessed and compared with the rehabilitation project through a snap-on device. After the intraoral adjustment and validation, the final rehabilitation was performed according to the information obtained in the provisional phase and digitally transmitted to the laboratory.

A modern approach to treating tooth wear aims to stop its progression at an early stage and, ideally, to install effective preventive measures or, in cases when it is already late, to intervene using an interceptive treatment approach. It is important to avoid the need for a full prosthetic treatment that implies additional tooth substance removal, with potential biologic complications. As signs of tooth wear often appear in young individuals, an interceptive treatment has the great potential of stabilizing tooth wear progression early using a no-prep approach and composite resins. The additional benefit of this treatment approach is its affordability and maintainability in the light of tooth wear being, usually, a lifelong pathology. Among the various options for restoring tooth wear lesions with composite resins, interest has lately been increasing for molding techniques (single or full) due to their efficiency and simplicity. This article describes modifications of the basic full molding technique to alleviate most of the known shortcomings of this method; namely, the index deformation, the time-consuming removal of excesses in the proximal and contact areas, and the possible insufficient precision in the molding of the occlusal anatomy. The 1- and 3-year follow-ups of both cases presented here confirmed the functional and esthetic quality of the results obtained with this technique. A kinesiographic and 3D superimposition of the posttreatment and 1-year results of one case provided additional perspectives on this treatment method.

Since the first introduction of the Cerec system (Sirona) in the early 1980s, the use of computer-aided design/computer-aided manufacture (CAD/CAM) technology has spread widely in modern adhesive dentistry. Thanks to this innovative technology, it has been possible to carry out chairside restorations fully managed by the clinician, with the advantages of lower costs for the patient, more rapid execution of the restorations, and the exclusion of the provisional phase. With further improvements in chairside technologies and materials, specifically in the field of composite resin blocks, it is now possible to fabricate multiple ultrathin, minimally invasive or even noninvasive restorations in one single appointment. The clinical case presented here was solved using an innovative approach: It was entirely studied and realized chairside by a dentist on a computer, without any plaster cast or classic articulator. Vertical dimension of occlusion (VDO) augmentation was projected with the 'Incisal Tip' tool on the virtual articulator of the Cerec system. Eight composite resin overlays were designed on the non-prepared posterior teeth of a patient suffering from generalized tooth loss principally caused by a history of bulimia nervosa. The maxillary anterior teeth were restored with six palatal veneers modified with direct composites from the vestibular side, in order to improve the esthetic integration of the restorations. The mandibular posterior teeth were built up with direct composites.