The effects of a periodontal ligament analogue on occlusal contact forces

Abstract

With structural and physiological functions, the periodontal ligament (PDL) is a complex component of the periodontium. It maintains the tooth in its equilibrium position and provides support within its bony socket. Additionally, the PDL is involved in tooth eruption and migration, orthodontic treatment-associated bone remodelling and root resorption, and the healing processes of disease and trauma. Despite wide-ranging studies, many of its biological and structural functions and characteristics remain poorly understood. As a load-bearing structure, the PDL's complexity derives from its anisotropy, as it consists of discrete components and functional elements, namely the matrix and the reinforcing principal fibers. 1,2 Moreover, as are most biological tissues, the PDL is characterised as a viscoelastic (VE) material. 3,4 Viscoelastic materials exhibit time-dependent mechanical behaviours, with 'creep' and 'recovery' specifically relevant to this study. Typically, while a constant force is applied to a VE material, it tends to continuously deform (creep). After the force is removed, the material tends to return towards its original dimensions (recovery) (https://polym erdat abase.com). In contrast, metals, for example, categorised as elastic-plastic materials, do not possess time-dependent features. Note that this is not a study of viscoelasticity, per se; rather, it is about its expression in the mechanical environment of occlusal contacts.This study represents the evolution of bench-top research in which the forces experienced by paired occluding (denture, ceramic and stainless steel) molars and full dentiform arches were measured. [5][6][7][8] In those studies, the teeth were rigidly attached (i.e.

Evaluation of stress distributions of calcium silicate-based root canal sealer in bulk or with main core material: A finite element analysis study

“…A commercially available multipurpose finite element software package, specifically ANSYS version 16.0, was utilized for the analyses. The obtained results were validated by comparing them to findings from similar studies conducted by Benazzi et al [17] and deMoya PLOS ONE et al [18], and demonstrated a satisfactory level of agreement. Within the scope of this research, eight cases were examined, compared, and extensively discussed in order to derive meaningful conclusions.…”

In vivo measurement of three-dimensional load exerted on dental implants: a literature review

“…Three factors affecting the load directional change during functions were suggested: the friction between the two contacting teeth, the contact sliding along the incline planes of the cusp, and the formation of new contacts and loss of existing contacts influenced by the periodontal ligament. However, these findings and suggestions were obtained from a simulation study [ 47 ]. The load exerted during bruxism might be an unexpectedly large load, thus causing some mechanical complications [ 48 ], and the magnitude of intraosseous stress during bruxism might destroy osseointegration [ 49 , 50 ].…”

“…The load on the tooth is controlled by a physiological neuromuscular mechanism, such as the muscle spindle and periodontal-masseteric reflex, during mastication [51,52]. However, mastication is normally carried out smoothly on implant prostheses, despite the lack of periodontal ligaments, which suggests some adaptive mechanisms related to tooth loss and replacement with implants, such as activation of periodontal ligament function of opposing teeth, elicitation of neuroplasticity, and activation of osseoperception [47,[53][54][55]. In vivo measured load data will greatly contribute to the elucidation of these mechanisms.…”