Effects of occlusal forces on the peri‐implant‐bone interface stability

Abstract

The Glossary of Prosthodontic Terms defines occlusion as the 'act or process of closure, being closed or shut off and the static relationship between the incising or masticating surfaces of the maxillary or mandibular teeth or tooth analogs'. 1 To achieve the dental occlusion, the skeletal and muscular systems work simultaneously to produce the mandibular movement, which transfers force to the prosthesis, teeth, implants, and adjacent supporting bone. 2 But the dental/implant occlusion is not just a simple contact between opposite surfaces. It is complex, and also includes the friction of multiple inclined planes and different force vectors (axial and nonaxial). 3 These force vectors occur simultaneously and are transient and therefore the concept of a unidirectional occlusal force should be replaced by the concept of multidirectional occlusal forces. 4 Additional forces of swallowing and sometimes parafunctions are applied to the system and overloading can appear. 2 Occlusal overload has been defined as the load greater than prostheses, implant components, or interface that tissues are capable of withstanding without damage. 1 For Laney, overload is occurring if the occlusal load exerted through function or parafunctions exceeds the resistance of the prosthesis, implant components, implant, and osseointegrated interface, resulting in structural or biological damage. 5 At the biological level, overload is produced when the amount of force overextends the adaptation capabilities of the host site. 6All the structures subject to occlusal forces can be exposed to physiological loading or overloading. 6 In the case of physiological loading, forces <3000 microstrains are dissipated through the occlusal surfaces, prosthetic structure, implant-abutment connection, retention screw, implant body, implant bone interface, and surrounding, supporting bone (Figure 1). 7 Meanwhile, overload strains >3000 microstrains might affect the weakest part of the system producing structural and/or biological failures. 8The applied occlusal bite forces are extremely difficult to quantify because they are not absolute and have great variability, which is influenced by factors such as duration, distribution, direction, and magnitude of forces. 9 Also, other factors such as the number and location of teeth and implants, their inclinations within the dental arch, the kind of restoration, and the bone quality can influence the resultant forces and therefore their accurate measurement. 10,11 In relation to the maximum biting forces produced in patients with osseointegrated implants, different magnitudes of occlusal forces have been recorded, with values ranging between 25 and 1000 N. [12][13][14][15][16][17][18][19][20][21][22][23] These studies agree that the forces transmitted by the anterior teeth are lower than those transmitted by the posterior teeth, that among the posterior teeth the second molar exerts the maximum levels of force, and that gender influences the bite force, with higher biting forces being generated by men compared with w...

Influence of restorative design on the progression of peri‐implant bone loss: A retrospective study

“…Therefore, the internal screw might play an important role in the progression of bone loss in the presence of peri‐implantitis. This is probably due to the fact that when implants are in function, occlusal forces are dissipated through the occlusal surfaces, prosthetic structure, implant‐abutment connection, internal screw, implant body, implant‐to‐bone interface, and surrounding bone 38,39 . In fact, when transverse occlusal forces are applied on an implant, bending of the implant components occurs and only a reduced portion of the supporting bone is involved in counteracting the load; leading to higher stress levels in particular portions of the implant‐bone interface 53 .…”

“…found that implants with restoration emergence angle ≥30° had significantly more marginal bone loss compared with implants with restoration emergence angle <30°, 5 years following functional loading 24 . When implants are in function, occlusal forces propagate from the occlusal surfaces to the implant‐abutment connection and further to the internal screw of the implant 38,39 . If occlusal overload occurs, the internal screw may be prone to fracture or loosening 40–42 .…”

“…If occlusal overload occurs, the internal screw may be prone to fracture or loosening 40–42 . However, if the loosening or fracture does not occur, the stress might be transmitted from the internal screw to the implant body, implant‐to‐bone interface, and surrounding bone 38,39 . Whether the force transmitted from the internal screw has an influence on the bone level surrounding the implant remains unknown.…”

Scientometric Analysis of Dental Implant Research over the Past 10 Years and Future Research Trends

“…Even we can draw a conclusion that the success of implants in clinical work is inseparable from the development of materials science. In addition to material science, the survival rate of implant is influenced by other factors including occlusal forces [61]. The correlation between them is also reflected in this study.…”

Concepts for prevention of complications in implant therapy

“…Although a relationship between bone loss and overloading has not yet been established, and experimental and clinical data are contradictory, the stimulatory/deleterious effects of mastication forces cannot be excluded as a potential factor that, in conjunction with plaque and inflammation, might result in crestal bone loss. The transmission of force from the restoration to the peri‐implant bone, and the mechanotransduction phenomena responsible for cell and tissue responses, have been addressed by Delgado‐Ruiz et al in this volume of Periodontology 2000 .…”