Estudio de la pérdida de material óseo en pacientes con bruxismo e implantes dentales

Abstract

Bruxism is an unconscious, involuntary and sustained motor activity that results in excessive teeth grinding and/or jaw clenching that could affect patients’ implants and rehabilitations. The accurate aetiology for bruxism remains ascertained, but it is known to involve multiple factors. The literature lacks studies on the possible effect of implant morphology on the resistance of the bone-implant osseointegrated interface when bruxism is present. Our objective was to assess the mechanical response of the bone-implant interface in bruxist patients whose implant prostheses are subjected to parafunctional cyclic loading over a simulated period of 10 years. With this objective, we started making a bibliographic revision about ‘bruxism’ as a condition and pathology, and ‘temporomandibular disorders’, as well as about their possible correlations with the marginal bone loss around dental implants. As a null hypothesis, we established that both the M-12 and the Astra implants would present similar levels of bone loss at the implant-bone interface after a 10-year simulation of bruxism. Therefore, a comparison was carried out between two types of implants (M- 12 and Astra Tech), and a pattern of bone loss was determined considering both the stress state and the cortical bone surface loss as the evaluation criteria. Numerical simulation techniques based on the finite element analysis method were applied in a dynamic analysis of the received forces; together with a constitutive model of bone remodelling that alters the physical properties of the bone. The simulated cortical bone surface loss at the implant neck area was 8.6% greater in the Astra implant than in the M-12 implant. Compared to the M-12 implant, the higher sustained stress observed over time in the Astra implant, together with the greater cortical bone surface loss that occurred at its neck area, may be related to a major probability of failure of those prostheses placed over Astra implants in bruxist patients.