Loading and composite restoration assessment of various non‐carious cervical lesions morphologies – 3D finite element analysis

Abstract

Background: The present study analysed the effects of different occlusal loading on premolars displaying various non-carious cervical lesions morphologies, restored (or not) with composites, by 3D finite element analysis. Methods: A three-dimensional digital model of a maxillary premolar was generated using CAD software. Three noncarious cervical lesions morphological types were simulated: wedged-shaped, saucer and mixed. All virtual models underwent three loading types (100 N): vertical, buccal and palatal loading. The simulated non-carious cervical lesions morphologies were analysed with and without restorations to consider specific regions, such as the occlusal and gingival walls as well as the depth of the lesions. Data summarizing the stress distribution were obtained in MPa using Maximum Principal Stress. Results: Palatal loads were responsible for providing the highest values of accumulated tensile stress on the buccal wall; 27.66 MPa and 25.76 MPa for mixed and wedged-shaped morphologies, respectively. The highest tensile values found on non-carious cervical lesions morphologies restored with composite resin were 5.9 MPa in the mixed morphology, similar to those found on sound models despite their morphologies and occlusal loading. Conclusions: The various non-carious cervical lesions morphologies had little effect on stress distribution patterns, whereas the loading type and presence of composite restorations influenced the biomechanical behaviour of the maxillary premolars.

Effects of non‐carious cervical lesion size, occlusal loading and restoration on biomechanical behaviour of premolar teeth

“…This is probably due to elimination of the ‘sharp’, wedge‐shaped apex after restoration with a resin composite (with elastic modulus similar to dentine), resulting in even distribution of occlusal loads. Our previous studies have also indicated that NCCLs with sharp, acute angles display greater stress concentration at the apex than those with rounded apices, and that the resin composite restorations result in similar distribution of stress in different types of NCCLs similar to sound teeth …”

Influence of anterior load and restorative procedure on maxillary incisors with different cervical wear morphologies

“…Among all factors involved in this process, the role of the stress has been much discussed in the literature (LEE;EAKLE, 1984;MICHAEL et al, 2009;GRIPPO et al, 2012;FRAGOSO et al, 2013;SOARES et al, 2015;ZEOLA et al, 2015). The term "abfraction" has been used for decades to describe the loss of tooth structure by overcoming bonds between hydroxyapatite crystals due to the stress concentration, distant from the area which the force was applied (LEE;EAKLE, 1984;GRIPPO et al, 2004;MICHAEL et al, 2009).…”

“…The term "abfraction" has been used for decades to describe the loss of tooth structure by overcoming bonds between hydroxyapatite crystals due to the stress concentration, distant from the area which the force was applied (LEE;EAKLE, 1984;GRIPPO et al, 2004;MICHAEL et al, 2009). Actually, occlusal interferences, parafunctional habits and bruxism change the magnitude, direction, frequency, duration and localization of the occlusal contacts, which result in different biomechanical behavior in these non-physiological situations (OMMERBORN et al, 2007;BRANDINI, PEDRINI, et al, 2012;BRANDINI, TREVISAN, et al, 2012;SOARES et al, 2015;ZEOLA et al, 2015). Then, these excessive loads generate dental tissues flexion which reaches the ultimate structure resistance and makes the structure more susceptible to other NCCLs etiological factors (LEE E EAKLE, 1984;MICHAEL et al, 2009).…”

Laser de Nd:YAG e pasta profilática de fosfosilicato de cálcio e sódio no tratamento da hipersensibilidade dentinária cervical: estudo clínico randomizado duplo-cego

“…Com a diminuição da prevalência da doença cárie, em resposta às bem sucedidas estratégias de promoção da saúde oral, mais atenção vem sendo dada às outras condições orais, como as lesões cervicais não-cariosas (LCNC) (Senna et al, 2012). Essas lesões são definidas como a perda da estrutura dental na junção esmalte-cemento, sem relação com atividade bacteriana (Mair, 1992;Holland et al, 1997;Soares et al, 2015) As LCNC possuem uma variedade de formas e são bastante comuns na prática clínica (Levitch et al, 1994). Possivelmente, o formato das lesões possui relação com sua etiologia Eakle, 1984) e a severidade e a prevalência aparentam ser maiores em indivíduos com idade mais avançada (Levitch et al, 1994;Schaffner, 2000).…”

“…A erosão/biocorrosão é definida como a dissolução de tecido dental, camada por camada, através da ação de ácidos, tanto extrínsecos quanto intrínsecos, como o ácido gástrico ou os provenientes da dieta. Já a abfração é a perda tecidual patológica dos tecidos dentais devido às cargas biomecânicas da mastigação, que resultam em flexão do dente e fadiga do esmalte e dentina com consequente fratura (Grippo, 1991;Soares et al, 2014;Soares et al, 2015). Lee e Eakle (1984) propuseram que o estresse tensional causado durante cargas oclusais possuem importante papel no desenvolvimento de lesões cervicais.…”