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The Journal of Prosthetic Dentistry Aug 2021There is a long-held assumption that teeth are superior to implants because the periodontal ligament (PDL) confers a preeminent defense against biologic and mechanical... (Review)
Review
STATEMENT OF PROBLEM
There is a long-held assumption that teeth are superior to implants because the periodontal ligament (PDL) confers a preeminent defense against biologic and mechanical challenges. However, adequate analysis of the literature is lacking. As a result, differential treatment planning of tooth- and implant-supported restorations has been compromised.
PURPOSE
Given an abundance and diversity of research, the purpose of this mapping review was to identify basic scientific gaps in the knowledge of how teeth and implants respond to biologic and mechanical loads. The findings will offer enhanced evidence-based clinical decision-making when considering replacement of periodontally compromised teeth and the design of implant prostheses.
MATERIAL AND METHODS
The online databases PubMed, Science Direct, and Web of Science were searched. Published work from 1965 to 2020 was collected and independently analyzed by both authors for inclusion in this review.
RESULTS
A total of 108 articles met the inclusion criteria of clinical, in vivo, and in vitro studies in the English language on the periradicular and peri-implant bone response to biologic and mechanical loads. The qualitative analysis found that the PDL's enhanced vascularity, stem cell ability, and resident cells that respond to inflammation allow for a more robust defense against biologic threats compared with implants. While the suspensory PDL acts to mediate moderate loads to the bone, higher compressive stress and strain within the PDL itself can initiate a biologic sequence of osteoclastic activity that can affect changes in the adjacent bone. Conversely, the peri-implant bone is more resistant to similar loads and the threshold for overload is higher because of the absence of a stress or strain sensitivity inherent in the PDL.
CONCLUSIONS
Based on this mapping review, teeth are superior to implants in their ability to resist biologic challenges, but implants are superior to teeth in managing higher compressive loads without prompting bone resorption.
Topics: Dental Implants; Humans; Periodontal Ligament; Tooth
PubMed: 32862999
DOI: 10.1016/j.prosdent.2020.07.002 -
Biomedicine & Pharmacotherapy =... Jan 2021Periodontitis is the most common chronic inflammatory disease, and a leading cause of tooth loss. Characterized by resorption of alveolar process and destruction of... (Review)
Review
Periodontitis is the most common chronic inflammatory disease, and a leading cause of tooth loss. Characterized by resorption of alveolar process and destruction of periodontal ligaments, periodontitis can impact not only periodontal tissues but also systemic diseases, such as diabetes, cardiovascular diseases, and respiratory infections. Currently, it is a hotspot to manage destruction and gain regeneration of periodontal tissues. Increasing evidence indicates that the Wnt signaling plays an important role in homeostasis of periodontal tissues, functions of periodontal derived cells, and progression of periodontitis. Its molecule expressions were abnormal in periodontitis. As such, modulators targeting the Wnt signaling may be an adjuvant therapy for periodontitis treatment. This review elucidates the role of Wnt signaling and its molecules, with a view to develop a potential application of drugs targeting the Wnt signaling for periodontitis treatment.
Topics: Animals; Anti-Inflammatory Agents; Humans; Molecular Targeted Therapy; Periodontal Ligament; Periodontitis; Periodontium; Stem Cells; Wnt Signaling Pathway
PubMed: 33227711
DOI: 10.1016/j.biopha.2020.110935 -
Cells May 2023Bone loss is a common problem that ranges from small defects to large defects after trauma, surgery, or congenital malformations. The oral cavity is a rich source of... (Review)
Review
UNLABELLED
Bone loss is a common problem that ranges from small defects to large defects after trauma, surgery, or congenital malformations. The oral cavity is a rich source of mesenchymal stromal cells (MSCs). Researchers have documented their isolation and studied their osteogenic potential. Therefore, the objective of this review was to analyze and compare the potential of MSCs from the oral cavity for use in bone regeneration.
METHODS
A scoping review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. The databases reviewed were PubMed, SCOPUS, Scientific Electronic Library Online (SciELO), and Web of Science. Studies using stem cells from the oral cavity to promote bone regeneration were included.
RESULTS
A total of 726 studies were found, of which 27 were selected. The MSCs used to repair bone defects were (I) dental pulp stem cells of permanent teeth, (II) stem cells derived from inflamed dental pulp, (III) stem cells from exfoliated deciduous teeth, (IV) periodontal ligament stem cells, (V) cultured autogenous periosteal cells, (VI) buccal fat pad-derived cells, and (VII) autologous bone-derived mesenchymal stem cells. Stem cells associate with scaffolds to facilitate insertion into the bone defect and to enhance bone regeneration. The biological risk and morbidity of the MSC-grafted site were minimal. Successful bone formation after MSC grafting has been shown for small defects with stem cells from the periodontal ligament and dental pulp as well as larger defects with stem cells from the periosteum, bone, and buccal fat pad.
CONCLUSIONS
Stem cells of maxillofacial origin are a promising alternative to treat small and large craniofacial bone defects; however, an additional scaffold complement is required for stem cell delivery.
Topics: Bone Regeneration; Mesenchymal Stem Cells; Osteogenesis; Periodontal Ligament; Stem Cells
PubMed: 37408226
DOI: 10.3390/cells12101392 -
Periodontology 2000 Jun 2023The clinical outcome of every prosthetic and restorative procedure depends on the maintenance of a healthy periodontium. It is, therefore, important that the... (Review)
Review
The clinical outcome of every prosthetic and restorative procedure depends on the maintenance of a healthy periodontium. It is, therefore, important that the prosthodontist and restorative dentist cause no harm or permanent damage to the underlying hard and soft tissues when performing clinical procedures necessary to carry out the planned treatment. Several factors involved in these procedures have been described to have an impact on gingival health. For the present article, a selection of four of these factors are presented with the goal of evaluating the current trends and their influence on periodontal structures: (1) tooth preparation configuration and apical extension, (2) gingival tissue sulcular expansion/retraction, (3) prosthetic contours, and (4) prosthesis marginal adaptation and the consequences of excess cement remnants. Based on the available scientific evidence and clinical experience, recommendations for the practitioner are given.
Topics: Humans; Periodontal Diseases; Periodontium; Gingiva; Periodontal Ligament
PubMed: 37466152
DOI: 10.1111/prd.12505 -
Compressive stress in periodontal ligament under orthodontic movements during periodontal breakdown.American Journal of Orthodontics and... Mar 2021This analysis aimed to assess quantitatively and qualitatively the compressive stress (S3) in periodontal ligament in a gradual periodontal breakdown (0-8 mm) under...
INTRODUCTION
This analysis aimed to assess quantitatively and qualitatively the compressive stress (S3) in periodontal ligament in a gradual periodontal breakdown (0-8 mm) under orthodontic movements. Correlations between the applied forces, the level of bone resorption, the decrease of force magnitude, and S3 increase were also conducted.
METHODS
On the basis of cone-beam computed tomography examinations (voxel size, 0.075 mm), nine 3-dimensional models of the second mandibular premolar with intact periodontium were created and then individually subjected to various levels of horizontal bone loss. Orthodontic forces (intrusion: 0.2 N; extrusion, rotation, tipping: 0.6 N; translation: 1.2 N) were applied on the brackets. Finite elements analysis was performed, and S3 stresses were quantitatively and qualitatively determined.
RESULTS
Translation and rotation induced the highest stress apically and cervically, whereas intrusion determined the lowest. Apical stress was lower than cervical stress. In intact periodontium, only intrusion and extrusion exhibited S3 stresses lower (apically and cervically) than maximum hydrostatic pressure (MHP) and maximum tolerable stress (MTS). In reduced periodontium, S3 stress (except for intrusion) exceeded MHP and MTS.
CONCLUSIONS
In reduced periodontium, forces of 0.2 N seems safe to be used. Forces of 0.6-1.2 N may produce stresses exceeding both MTS and MHP, endangering the periodontium. S3 failure criterion (despite its widely use) seems not to be adequate for accurate quantitative results when evaluating the stress in the periodontal ligament while remaining adequate for qualitative results. An overall correlation between the applied force, S3 increase, and periodontal breakdown applicable to all 5 movements could not be established-this was possible only for sole movements.
Topics: Computer Simulation; Cone-Beam Computed Tomography; Finite Element Analysis; Humans; Models, Biological; Periodontal Ligament; Pressure; Stress, Mechanical; Tooth Movement Techniques
PubMed: 33487500
DOI: 10.1016/j.ajodo.2020.10.021 -
Acta Biomaterialia Sep 2022Periodontal regeneration is characterized by the attachment of oblique periodontal ligament fibres on the tooth root surface. To facilitate periodontal ligament...
Periodontal regeneration is characterized by the attachment of oblique periodontal ligament fibres on the tooth root surface. To facilitate periodontal ligament attachment, a fibre-guiding tissue engineered biphasic construct was manufactured by melt electrowriting (MEW) for influencing reproducible cell guidance and tissue orientation. The biphasic scaffold contained fibre-guiding features in the periodontal ligament component comprising of 100 µm spaced channels (100CH), a pore size gradient in the bone component and maintained a highly porous and fully interconnected interface between the compartments. The efficacy of the fibre-guiding channels was assessed in an ectopic periodontal attachment model in immunocompromised rats. This demonstrated an unprecedented and systematic tissue alignment perpendicular to the dentin in the 100CH group, resulting in the close mimicry of native periodontal ligament architecture. In addition, the histology revealed high levels of tissue integration between the two compartments as observed by the perpendicular collagen attachment on the dentin surface, which also extended and infiltrated the scaffold's bone compartment. In conclusion, the 100 µm fibre-guiding scaffold induced a systematic tissue orientation at the dentin-ligament interface, resembling the native periodontium and thus resulting in enhanced alignment mimicking periodontal ligament regeneration. STATEMENT OF SIGNIFICANCE: Periodontitis is a prevalent inflammatory disease affecting a large portion of the adult population and leading to the destruction of the tooth-supporting structures (alveolar bone, periodontal ligament, and cementum). Current surgical treatments are unpredictable and generally result in repair rather than functional regeneration. A key feature of functional regeneration is the re-insertion of the oblique or perpendicularly orientated periodontal ligament fibre in both the alveolar bone and root surface. This study demonstrates that a highly porous scaffold featuring 100 µm width channels manufactured by the stacking of melt electrospun fibres, induced perpendicular alignment and attachment of the neo-ligament onto a dentine surface. The fibre guiding micro-architecture may pave the way for enhanced and more functional regeneration of the periodontium.
Topics: Animals; Collagen; Dental Cementum; Ligaments; Periodontal Ligament; Periodontium; Rats; Tissue Engineering
PubMed: 35853598
DOI: 10.1016/j.actbio.2022.07.023 -
American Journal of Orthodontics and... Feb 2022This research aimed to assess qualitatively and quantitatively the overall stress in the periodontal ligament during gradual periodontal breakdown (0-8 mm) under...
INTRODUCTION
This research aimed to assess qualitatively and quantitatively the overall stress in the periodontal ligament during gradual periodontal breakdown (0-8 mm) under orthodontic movements. Correlations between the applied forces, the level of bone loss, the decrease of force magnitude, and the increase of stress were also assessed.
METHODS
On the basis of cone-beam computed tomography examinations (voxel size, 0.075 mm), nine 3-dimensional models of a mandibular second premolar with intact periodontium were created and then individually subjected to various levels of horizontal bone loss. Orthodontic forces (intrusion at 0.2 N; extrusion, rotation, and tipping at 0.6 N; translation at 1.2 N) were applied on the brackets. Finite elements analysis was performed, and von Mises (VM) stresses were quantitatively and qualitatively determined.
RESULTS
Rotation and translation induced the highest stress apically and cervically, whereas intrusion determined the lowest. Apical stress was lower than cervical stress. In intact periodontium, VM stress was under maximum hydrostatic pressure (MHP) and maximum tolerable stress (MTS). In reduced periodontium, VM stress was lower apically than MHP, whereas cervically, the rotation, translation, and tipping exceeded MHP.
CONCLUSIONS
A force of 1.2 N seemed safe to be used in the intact periodontium. Forces higher than 0.6 N could produce stresses exceeding MHP and MTS endangering the reduced periodontium. VM stress failure criterion (despite its limited use) seemed to be more adequate for accurate quantitative results. An overall correlation between the applied force, VM stress increase, and periodontal breakdown applicable to all 5 movements could not be established. This was possible only for individual movements.
Topics: Computer Simulation; Finite Element Analysis; Humans; Models, Biological; Periodontal Ligament; Stress, Mechanical; Tooth Movement Techniques
PubMed: 34563425
DOI: 10.1016/j.ajodo.2021.06.014 -
International Journal of Pharmaceutics Sep 2022Periodontitis is a chronic infectious and inflammatory disease of periodontal tissues estimated to affect 70-80 % of all adults. At the same time, periodontium, the... (Review)
Review
Periodontitis is a chronic infectious and inflammatory disease of periodontal tissues estimated to affect 70-80 % of all adults. At the same time, periodontium, the site of periodontal pathologies, is an extraordinarily complex plexus of soft and hard tissues, the regeneration of which using even the most advanced forms of tissue engineering continues to be a challenge. Nanotechnologies, meanwhile, have provided exquisite tools for producing biomaterials and pharmaceutical formulations capable of elevating the efficacies of standard pharmacotherapies and surgical approaches to whole new levels. A bibliographic analysis provided here demonstrates a continuously increasing research output of studies on the use of nanotechnologies in the management of periodontal disease, even when they are normalized to the total output of studies on periodontitis. The great majority of biomaterials used to tackle periodontitis, including those that pioneered this interesting field, have been polymeric. In this article, a chronological review of polymeric nanotechnologies for the treatment of periodontitis is provided, focusing on the major conceptual innovations since the late 1990s, when the first nanostructures for the treatment of periodontal diseases were fabricated. In the opening sections, the etiology and pathogenesis of periodontitis and the anatomical and histological characteristics of the periodontium are being described, along with the general clinical manifestations of the disease and the standard means of its therapy. The most prospective chemistries in the design of polymers for these applications are also elaborated. It is concluded that the amount of innovation in this field is on the rise, despite the fact that most studies are focused on the refinement of already established paradigms in tissue engineering rather than on the development of revolutionary new concepts.
Topics: Biocompatible Materials; Humans; Nanotechnology; Periodontal Diseases; Periodontal Ligament; Periodontitis; Polymers; Prospective Studies; Regeneration
PubMed: 35932930
DOI: 10.1016/j.ijpharm.2022.122065 -
Stem Cell Research & Therapy Dec 2022Periodontitis often causes irrevocable destruction of tooth-supporting tissues and eventually leads to tooth loss. Currently, stem cell-based tissue engineering has... (Review)
Review
BACKGROUND
Periodontitis often causes irrevocable destruction of tooth-supporting tissues and eventually leads to tooth loss. Currently, stem cell-based tissue engineering has achieved a favorable result in regenerating periodontal tissues. Moreover, cell-free therapies that aim to facilitate the recruitment of resident repair cell populations to injured sites by promoting cell mobilization and homing have become alternative options to cell therapy.
MAIN TEXT
Cell aggregates (e.g., cell sheets) retain a large amount of extracellular matrix which can improve cell viability and survival rates after implantation in vivo. Electrostatic spinning and 3D bioprinting through fabricating specific alignments and interactions scaffold structures have made promising outcomes in the construction of a microenvironment conducive to periodontal regeneration. Cell-free therapies with adding biological agents (growth factors, exosomes and conditioned media) to promote endogenous regeneration have somewhat addressed the limitations of cell therapy.
CONCLUSION
Hence, this article reviews the progress of stem cell-based tissue engineering and advanced strategies for endogenous regeneration based on stem cell derivatives in periodontal regeneration.
Topics: Humans; Periodontium; Periodontitis; Tissue Engineering; Stem Cells; Cell- and Tissue-Based Therapy; Periodontal Ligament
PubMed: 36575471
DOI: 10.1186/s13287-022-03225-z -
Journal of Dental Research Nov 2022Successful periodontal repair and regeneration requires the coordinated responses from soft and hard tissues as well as the soft tissue-to-bone interfaces. Inspired by...
Successful periodontal repair and regeneration requires the coordinated responses from soft and hard tissues as well as the soft tissue-to-bone interfaces. Inspired by the hierarchical structure of native periodontal tissues, tissue engineering technology provides unique opportunities to coordinate multiple cell types into scaffolds that mimic the natural periodontal structure in vitro. In this study, we designed and fabricated highly ordered multicompartmental scaffolds by melt electrowriting, an advanced 3-dimensional (3D) printing technique. This strategy attempted to mimic the characteristic periodontal microenvironment through multicompartmental constructs comprising 3 tissue-specific regions: 1) a bone compartment with dense mesh structure, 2) a ligament compartment mimicking the highly aligned periodontal ligaments (PDLs), and 3) a transition region that bridges the bone and ligament, a critical feature that differentiates this system from mono- or bicompartmental alternatives. The multicompartmental constructs successfully achieved coordinated proliferation and differentiation of multiple cell types in vitro within short time, including both ligamentous- and bone-derived cells. Long-term 3D coculture of primary human osteoblasts and PDL fibroblasts led to a mineral gradient from calcified to uncalcified regions with PDL-like insertions within the transition region, an effect that is challenging to achieve with mono- or bicompartmental platforms. This process effectively recapitulates the key feature of interfacial tissues in periodontium. Collectively, this tissue-engineered approach offers a fundament for engineering periodontal tissue constructs with characteristic 3D microenvironments similar to native tissues. This multicompartmental 3D printing approach is also highly compatible with the design of next-generation scaffolds, with both highly adjustable compartmentalization properties and patient-specific shapes, for multitissue engineering in complex periodontal defects.
Topics: Humans; Tissue Engineering; Tissue Scaffolds; Periodontium; Printing, Three-Dimensional; Periodontal Ligament
PubMed: 35689382
DOI: 10.1177/00220345221099823