Urbano Santana-Penín - Profile on Academia.edu (original) (raw)
Papers by Urbano Santana-Penín
Utilidad de los portales audiovisuales en formación autodirigida sobre contaminación cruzada en odontología
XV Foro internacional sobre la evaluación de la calidad de la investigación y de la educación superior: (FECIES), 2018, 2018, ISBN 978-84-09-02098-0, págs. 589-595, 2018
Cranio-the Journal of Craniomandibular Practice, Jan 2, 2016
Objectives/hypothesis: This study assessed the kinesiographic recordings of jaw movements during ... more Objectives/hypothesis: This study assessed the kinesiographic recordings of jaw movements during reading a text in Galician and Spanish language. Study design: Cross-sectional blind study. Methods: A homogeneous healthy group of 25 normal stomatognathic system and native Galician participants was studied. Frontal and parasagittal plane recordings of the intraborder lateral jaw movements and during reading Galician and Spanish texts were recorded using a calibrated jaw-tracking device kinesiograph. Results: Although movements were similar in both languages, a greater retrusion of the jaw in the Spanish language was shown; moreover, a tendency exists for a left side motion envelope in this right-handedness preference sample. Conclusions: This study supports the hypothesis that speech is controlled by the central nervous system rather than by peripheral factors, and that the hemispheric dominance influences the asymmetry of the speech envelope.
PLOS ONE, Apr 8, 2013
Background: Temporomandibular disorders are the most common cause of chronic orofacial pain, but,... more Background: Temporomandibular disorders are the most common cause of chronic orofacial pain, but, except where they occur subsequent to trauma, their cause remains unknown. This cross-sectional study assessed chewing function (habitual chewing side) and the differences of the chewing side and condylar path and lateral anterior guidance angles in participants with chronic unilateral temporomandibular disorder. This is the preliminary report of a randomized trial that aimed to test the effect of a new occlusal adjustment therapy. Methods: The masticatory function of 21 randomly selected completely dentate participants with chronic temporomandibular disorders (all but one with unilateral symptoms) was assessed by observing them eat almonds, inspecting the lateral horizontal movement of the jaw, with kinesiography, and by means of interview. The condylar path in the sagittal plane and the lateral anterior guidance angles with respect to the Frankfort horizontal plane in the frontal plane were measured on both sides in each individual. Results: Sixteen of 20 participants with unilateral symptoms chewed on the affected side; the concordance (Fisher's exact test, P = .003) and the concordance-symmetry level (Kappa coefficient k = 0.689; 95% confidence interval [CI], 0.38 to 0.99; P = .002) were significant. The mean condylar path angle was steeper (53.47(10.88) degrees versus 46.16(7.25) degrees; P = .001), and the mean lateral anterior guidance angle was flatter (41.63(13.35) degrees versus 48.32(9.53) degrees P = .036) on the symptomatic side. Discussion: The results of this study support the use of a new term based on etiology, ''habitual chewing side syndrome'', instead of the nonspecific symptom-based ''temporomandibular joint disorders''; this denomination is characterized in adults by a steeper condylar path, flatter lateral anterior guidance, and habitual chewing on the symptomatic side.
Journal of Prosthetic Dentistry, Sep 1, 1998
The cosmetic appearance of a removable partial denture is of great importance to both the patient... more The cosmetic appearance of a removable partial denture is of great importance to both the patient and the dentist. Traditional facial clasp arms are usually unsighdy. Other options are expensive and/or technically difficult, and may require time-consuming maintenance. Furthermore, when these clasps are broken, replacement of the entire removable partial denture may be required. This article describes a procedure for making a simple but effective twin-flex clasp. The clasp has excellent esthetics and can be readily adjusted or replaced.
Pain Medicine, Dec 19, 2013
We congratulate the authors for publishing their manuscript entitled "Surface Electromyography Fi... more We congratulate the authors for publishing their manuscript entitled "Surface Electromyography Findings in Unilateral Myofascial Pain Patients: Comparison of Painful vs Non Painful Sides" [1] in a recent issue of Pain Medicine. Future research strategies to elucidate the causes of temporomandibular joint (TMJ) disorders (TMD) will benefit from investigations of this complex initial TMD condition. The study assessed the muscular electromyographic activity in a clinical context and thus provided information that could be clinically valuable.
Jornada de jóvenes investigadores del I3A, May 25, 2018
Contemporary eating habits may cause malformations in children jaw, that are difficult to evaluat... more Contemporary eating habits may cause malformations in children jaw, that are difficult to evaluate and treat clinically. In this work, a computational methodology for the diagnosis and the treatment of this pathology is proposed. It combines porous-fibrous material models, medical devices and computational models of patients with facial asymmetries from the perspective of neuroocclusal rehabilitation.
Journal of Prosthetic Dentistry, Nov 1, 1998
Journal of Prosthetic Dentistry, Sep 1, 1998
Journal of Prosthetic Dentistry, Nov 1, 1998
In recent years, a number of reports have proposed procedures for registering jaw relation and ma... more In recent years, a number of reports have proposed procedures for registering jaw relation and making the altered-cast impression during the same visit as the framework try-in. 1,2 By minimizing the number of visits, such an approach reduces both the cost of the treatment and inconvenience to the patient. To make an altered-cast impression 3 correctly requires that the framework remain in exactly the same position as during the try-in. Problems often arise because the impression material placed between framework and mucosa may cause the framework to lift away from the mucosa; subsequently, during flasking, the framework will depress again, producing inaccuracies in the prosthesis. An attempt can be made to counter this problem by pressing down on the framework with the fingers while making the impression; however, this may not give acceptable results, because it is difficult to judge how much pressure to exert; in addition, the act of pressing down may itself cause slight displacements. An alternative approach is to take the altered-cast impression first, and then to obtain a jaw relation record in silicone. 2 This procedure has 2 major disadvantages: (1) It is difficult to ensure that the framework will remain in the correct position, and (2) the impression material used for obtaining the jaw relation record may be displaced slightly, leading to inaccuracies in the final structure. Another possibility is to use the framework as record base 3,4 ; however, this procedure is also sometimes inaccurate. This article describes an accurate procedure for registering the jaw relation and making the altered-cast impression during the same session as the framework try-in for the removable partial denture (RPD).
International Journal for Numerical Methods in Biomedical Engineering, Feb 6, 2019
The periodontal ligament (PDL) is a soft biological tissue that connects the tooth with the trabe... more The periodontal ligament (PDL) is a soft biological tissue that connects the tooth with the trabecular bone of the mandible. It plays a key role in load transmission and is primarily responsible for bone resorption and most common periodontal diseases. Although several numerical studies have analysed the biomechanical response of the PDL, most did not consider its porous fibrous structure, and only a few analysed damage to the PDL. This study presents an innovative numerical formulation of a porous fibrous hyperelastic damage material model for the PDL. The model considers two separate softening phenomena: fibre alignment during loading and fibre rupture. The parameters for the material model characterization were fitted using experimental data from the literature. Furthermore, the experimental tests used for characterization were computationally modelled to verify the material parameters. A finite element model of a portion of a human mandible, obtained by micro-computerized tomography, was developed, and the proposed constitutive model was implemented for the PDL. Our results confirm that damage to the PDL may occur mainly due to overpressure of the interstitial fluid, while large forces must be applied to damage the PDL fibrous network. Moreover, this study clarifies some aspects of the relationship between PDL damage and the bone remodelling process.
Electromyographic activity in patients with temporomandibular disorders
Journal of Oral Rehabilitation, Nov 1, 2000
Evaluation of masticatory muscle activity by surface electromyography (EMG) is a valuable tool fo... more Evaluation of masticatory muscle activity by surface electromyography (EMG) is a valuable tool for diagnosing dysfunction of the masticatory apparatus. However, controversy exists with regard to the usefulness of the EMG for patients with temporomandibular disorders (TMD). Forty patients with TMD were subjected to surface EMG of the masticatory muscles. These patients had consulted because of temporomandibular pain and clicks. In most cases (75%), the symptoms affected the patient's left side. Overall mean resting activity was 2.52 microV+/-1.25 microV (s.d.), which is slightly higher than in comparable healthy subjects (1.92+/-1.20 microV). Mean resting activity was highest in the anterior digastric muscle (3.49 microV) on the left side. Overall mean activity during clenching was 66.77+/-35.22 microV, which is about half that observed in healthy subjects (110.30+/-82.97 microV). During leftward movement of the jaw, activity was on average highest in the left digastric, while during rightward movement, activity was on average highest in the right anterior temporal (AT). Our results thus indicate that patients with temporomandibular joint (TMJ) disorder show: (1) a slight increase in basal tone; (2) a significantly reduced capacity for clenching; and (3) an apparently paradoxical inhibition of the dysfunctional-side AT during movement of the mandible towards that side.
Remodeling dental anatomy vs sham therapy for chronic temporomandibular disorders. A placebo-controlled randomized clinical trial
Annals of Anatomy - Anatomischer Anzeiger
Perno-muñón colado. Parte II
RCOE: Revista del Ilustre Consejo General de Colegios de Odontólogos y Estomatólogos de España, 2000
Finite element model of the nonlinear behaviour of the human periodontal ligament
It is well known that the periodontal ligament (PDL) plays a key role in transferring loads from ... more It is well known that the periodontal ligament (PDL) plays a key role in transferring loads from the teeth to the alveolar bone, and it is becoming increasingly difficult to ignore that PDL performs greatly in tooth movements [1]. Some authors stress that the use of 3D geometry is mandatory; and plane models should never be used to simulate the tooth/bone system under load [2]. Although, more recent studies [3] proposed porohyperelastic models, the material properties of PDL are still not clarified [2][3]. The aim of this study is to validate and evaluate a finite element (FE) model based on the real geometry of a specimen extracted from a fresh human cadaver obtained by computer micro-tomography (µCT). For that purpose, the PDL behaviour was defined as a porous hyperelastic anisotropic material.
Diagnosis of TMJ disorders using parametric numerical models obtained by active shape model of orthopantomography
Some temporomandibular joint (TMJ) disorders start during childhood. An early treatment can avoid... more Some temporomandibular joint (TMJ) disorders start during childhood. An early treatment can avoid later surgical operation. However, it is difficult to design an early treatment because of the radiation that computed tomography scanner causes to children [1]. Also, the orthopantomography (OPG) is a planar image that causes difficulty to study the TMJ [2]. Thus, the purpose of this study is to design a computational tool able to represent the stresses at the TMJ by using an OPG image. For that purpose, a parametric finite element (FE) model of the human TMJ using active shape models (ASM) [3] obtained by OPGs was developed.
Computational analysis of craniomandibular tissues for the correction of mandibular asymmetries in childhood
The craniofacial asymmetry, which is defined as the size difference between the left and right he... more The craniofacial asymmetry, which is defined as the size difference between the left and right hemi-faces, is a consequence of a different growth of the mandibular ramus. This difference may be due to the unilateral chewing, to occlusal interferences, or to muscle-bone dynamic alterations. All of them with great biomechanical importance. This morphological difference is aggravated during growth, since it not only causes an anomalous esthetic effect but, furthermore induces limitations on the chewing functional habits, temporomandibular disorders (TMD), or disorders of the ear, among others. Despite it has been demonstrated the relation between the malocclusion and the skeleton disproportion [1], and it has been simulated numerically the chewing biomechanics [2], currently the correction of facial abnormalities on children is made from a clinical point of view, exclusively. There are not computational simulations that consider the real morphology of the mandibular asymmetry, or the f...
Cambios dimensionales en la polimerización de las resinas
Jornada de Jóvenes Investigadores del I3A, 2018
Contemporary eating habits may cause malformations in children jaw, that are difficult to evaluat... more Contemporary eating habits may cause malformations in children jaw, that are difficult to evaluate and treat clinically. In this work, a computational methodology for the diagnosis and the treatment of this pathology is proposed. It combines porous-fibrous material models, medical devices and computational models of patients with facial asymmetries from the perspective of neuro-occlusal rehabilitation.
Journal of the Mechanical Behavior of Biomedical Materials, 2018
The periodontal ligament (PDL) is a porous and fibrous soft tissue situated around the tooth, whi... more The periodontal ligament (PDL) is a porous and fibrous soft tissue situated around the tooth, which plays a key role in the transmission of loads from the tooth to the alveolar bone of the mandible. Although several studies have tried to characterize its mechanical properties, the behaviour of this tissue is not clear yet. In this study, a new simulation methodology based on a material model which considers the contribution of porous and fibrous structure with different material model formulations depending on the effort direction is proposed. The defined material model was characterized by a non-linear approximation of the porous fibrous matrix to experimental results obtained from samples of similar species and was validated by rigorous test simulations under tensile and compressive loads. The global PDL response was also validated using the parameters of the characterization in a finite element model of full human canine tooth obtained by micro-tomography. The results suggest that the porous contribution has high influence during compression because the bulk modulus of the material depends on the ability of interstitial fluid to drain. On the other hand, the collagen fibres running along the load direction are the main responsible of the ligament stiffness during tensile efforts. Thus, a material model with distinct responses depending of the load direction is proposed. Furthermore, the results suggest the importance of considering 3D finite element models based of the real morphology of human PDL for representing the irregular stress distribution caused by the coupling of complex material models and irregular morphologies.
Minimally invasive complete rehabilitation of severe wear: one year follow up
Journal of Clinical and Experimental Dentistry, 2017
Utilidad de los portales audiovisuales en formación autodirigida sobre contaminación cruzada en odontología
XV Foro internacional sobre la evaluación de la calidad de la investigación y de la educación superior: (FECIES), 2018, 2018, ISBN 978-84-09-02098-0, págs. 589-595, 2018
Cranio-the Journal of Craniomandibular Practice, Jan 2, 2016
Objectives/hypothesis: This study assessed the kinesiographic recordings of jaw movements during ... more Objectives/hypothesis: This study assessed the kinesiographic recordings of jaw movements during reading a text in Galician and Spanish language. Study design: Cross-sectional blind study. Methods: A homogeneous healthy group of 25 normal stomatognathic system and native Galician participants was studied. Frontal and parasagittal plane recordings of the intraborder lateral jaw movements and during reading Galician and Spanish texts were recorded using a calibrated jaw-tracking device kinesiograph. Results: Although movements were similar in both languages, a greater retrusion of the jaw in the Spanish language was shown; moreover, a tendency exists for a left side motion envelope in this right-handedness preference sample. Conclusions: This study supports the hypothesis that speech is controlled by the central nervous system rather than by peripheral factors, and that the hemispheric dominance influences the asymmetry of the speech envelope.
PLOS ONE, Apr 8, 2013
Background: Temporomandibular disorders are the most common cause of chronic orofacial pain, but,... more Background: Temporomandibular disorders are the most common cause of chronic orofacial pain, but, except where they occur subsequent to trauma, their cause remains unknown. This cross-sectional study assessed chewing function (habitual chewing side) and the differences of the chewing side and condylar path and lateral anterior guidance angles in participants with chronic unilateral temporomandibular disorder. This is the preliminary report of a randomized trial that aimed to test the effect of a new occlusal adjustment therapy. Methods: The masticatory function of 21 randomly selected completely dentate participants with chronic temporomandibular disorders (all but one with unilateral symptoms) was assessed by observing them eat almonds, inspecting the lateral horizontal movement of the jaw, with kinesiography, and by means of interview. The condylar path in the sagittal plane and the lateral anterior guidance angles with respect to the Frankfort horizontal plane in the frontal plane were measured on both sides in each individual. Results: Sixteen of 20 participants with unilateral symptoms chewed on the affected side; the concordance (Fisher's exact test, P = .003) and the concordance-symmetry level (Kappa coefficient k = 0.689; 95% confidence interval [CI], 0.38 to 0.99; P = .002) were significant. The mean condylar path angle was steeper (53.47(10.88) degrees versus 46.16(7.25) degrees; P = .001), and the mean lateral anterior guidance angle was flatter (41.63(13.35) degrees versus 48.32(9.53) degrees P = .036) on the symptomatic side. Discussion: The results of this study support the use of a new term based on etiology, ''habitual chewing side syndrome'', instead of the nonspecific symptom-based ''temporomandibular joint disorders''; this denomination is characterized in adults by a steeper condylar path, flatter lateral anterior guidance, and habitual chewing on the symptomatic side.
Journal of Prosthetic Dentistry, Sep 1, 1998
The cosmetic appearance of a removable partial denture is of great importance to both the patient... more The cosmetic appearance of a removable partial denture is of great importance to both the patient and the dentist. Traditional facial clasp arms are usually unsighdy. Other options are expensive and/or technically difficult, and may require time-consuming maintenance. Furthermore, when these clasps are broken, replacement of the entire removable partial denture may be required. This article describes a procedure for making a simple but effective twin-flex clasp. The clasp has excellent esthetics and can be readily adjusted or replaced.
Pain Medicine, Dec 19, 2013
We congratulate the authors for publishing their manuscript entitled "Surface Electromyography Fi... more We congratulate the authors for publishing their manuscript entitled "Surface Electromyography Findings in Unilateral Myofascial Pain Patients: Comparison of Painful vs Non Painful Sides" [1] in a recent issue of Pain Medicine. Future research strategies to elucidate the causes of temporomandibular joint (TMJ) disorders (TMD) will benefit from investigations of this complex initial TMD condition. The study assessed the muscular electromyographic activity in a clinical context and thus provided information that could be clinically valuable.
Jornada de jóvenes investigadores del I3A, May 25, 2018
Contemporary eating habits may cause malformations in children jaw, that are difficult to evaluat... more Contemporary eating habits may cause malformations in children jaw, that are difficult to evaluate and treat clinically. In this work, a computational methodology for the diagnosis and the treatment of this pathology is proposed. It combines porous-fibrous material models, medical devices and computational models of patients with facial asymmetries from the perspective of neuroocclusal rehabilitation.
Journal of Prosthetic Dentistry, Nov 1, 1998
Journal of Prosthetic Dentistry, Sep 1, 1998
Journal of Prosthetic Dentistry, Nov 1, 1998
In recent years, a number of reports have proposed procedures for registering jaw relation and ma... more In recent years, a number of reports have proposed procedures for registering jaw relation and making the altered-cast impression during the same visit as the framework try-in. 1,2 By minimizing the number of visits, such an approach reduces both the cost of the treatment and inconvenience to the patient. To make an altered-cast impression 3 correctly requires that the framework remain in exactly the same position as during the try-in. Problems often arise because the impression material placed between framework and mucosa may cause the framework to lift away from the mucosa; subsequently, during flasking, the framework will depress again, producing inaccuracies in the prosthesis. An attempt can be made to counter this problem by pressing down on the framework with the fingers while making the impression; however, this may not give acceptable results, because it is difficult to judge how much pressure to exert; in addition, the act of pressing down may itself cause slight displacements. An alternative approach is to take the altered-cast impression first, and then to obtain a jaw relation record in silicone. 2 This procedure has 2 major disadvantages: (1) It is difficult to ensure that the framework will remain in the correct position, and (2) the impression material used for obtaining the jaw relation record may be displaced slightly, leading to inaccuracies in the final structure. Another possibility is to use the framework as record base 3,4 ; however, this procedure is also sometimes inaccurate. This article describes an accurate procedure for registering the jaw relation and making the altered-cast impression during the same session as the framework try-in for the removable partial denture (RPD).
International Journal for Numerical Methods in Biomedical Engineering, Feb 6, 2019
The periodontal ligament (PDL) is a soft biological tissue that connects the tooth with the trabe... more The periodontal ligament (PDL) is a soft biological tissue that connects the tooth with the trabecular bone of the mandible. It plays a key role in load transmission and is primarily responsible for bone resorption and most common periodontal diseases. Although several numerical studies have analysed the biomechanical response of the PDL, most did not consider its porous fibrous structure, and only a few analysed damage to the PDL. This study presents an innovative numerical formulation of a porous fibrous hyperelastic damage material model for the PDL. The model considers two separate softening phenomena: fibre alignment during loading and fibre rupture. The parameters for the material model characterization were fitted using experimental data from the literature. Furthermore, the experimental tests used for characterization were computationally modelled to verify the material parameters. A finite element model of a portion of a human mandible, obtained by micro-computerized tomography, was developed, and the proposed constitutive model was implemented for the PDL. Our results confirm that damage to the PDL may occur mainly due to overpressure of the interstitial fluid, while large forces must be applied to damage the PDL fibrous network. Moreover, this study clarifies some aspects of the relationship between PDL damage and the bone remodelling process.
Electromyographic activity in patients with temporomandibular disorders
Journal of Oral Rehabilitation, Nov 1, 2000
Evaluation of masticatory muscle activity by surface electromyography (EMG) is a valuable tool fo... more Evaluation of masticatory muscle activity by surface electromyography (EMG) is a valuable tool for diagnosing dysfunction of the masticatory apparatus. However, controversy exists with regard to the usefulness of the EMG for patients with temporomandibular disorders (TMD). Forty patients with TMD were subjected to surface EMG of the masticatory muscles. These patients had consulted because of temporomandibular pain and clicks. In most cases (75%), the symptoms affected the patient's left side. Overall mean resting activity was 2.52 microV+/-1.25 microV (s.d.), which is slightly higher than in comparable healthy subjects (1.92+/-1.20 microV). Mean resting activity was highest in the anterior digastric muscle (3.49 microV) on the left side. Overall mean activity during clenching was 66.77+/-35.22 microV, which is about half that observed in healthy subjects (110.30+/-82.97 microV). During leftward movement of the jaw, activity was on average highest in the left digastric, while during rightward movement, activity was on average highest in the right anterior temporal (AT). Our results thus indicate that patients with temporomandibular joint (TMJ) disorder show: (1) a slight increase in basal tone; (2) a significantly reduced capacity for clenching; and (3) an apparently paradoxical inhibition of the dysfunctional-side AT during movement of the mandible towards that side.
Remodeling dental anatomy vs sham therapy for chronic temporomandibular disorders. A placebo-controlled randomized clinical trial
Annals of Anatomy - Anatomischer Anzeiger
Perno-muñón colado. Parte II
RCOE: Revista del Ilustre Consejo General de Colegios de Odontólogos y Estomatólogos de España, 2000
Finite element model of the nonlinear behaviour of the human periodontal ligament
It is well known that the periodontal ligament (PDL) plays a key role in transferring loads from ... more It is well known that the periodontal ligament (PDL) plays a key role in transferring loads from the teeth to the alveolar bone, and it is becoming increasingly difficult to ignore that PDL performs greatly in tooth movements [1]. Some authors stress that the use of 3D geometry is mandatory; and plane models should never be used to simulate the tooth/bone system under load [2]. Although, more recent studies [3] proposed porohyperelastic models, the material properties of PDL are still not clarified [2][3]. The aim of this study is to validate and evaluate a finite element (FE) model based on the real geometry of a specimen extracted from a fresh human cadaver obtained by computer micro-tomography (µCT). For that purpose, the PDL behaviour was defined as a porous hyperelastic anisotropic material.
Diagnosis of TMJ disorders using parametric numerical models obtained by active shape model of orthopantomography
Some temporomandibular joint (TMJ) disorders start during childhood. An early treatment can avoid... more Some temporomandibular joint (TMJ) disorders start during childhood. An early treatment can avoid later surgical operation. However, it is difficult to design an early treatment because of the radiation that computed tomography scanner causes to children [1]. Also, the orthopantomography (OPG) is a planar image that causes difficulty to study the TMJ [2]. Thus, the purpose of this study is to design a computational tool able to represent the stresses at the TMJ by using an OPG image. For that purpose, a parametric finite element (FE) model of the human TMJ using active shape models (ASM) [3] obtained by OPGs was developed.
Computational analysis of craniomandibular tissues for the correction of mandibular asymmetries in childhood
The craniofacial asymmetry, which is defined as the size difference between the left and right he... more The craniofacial asymmetry, which is defined as the size difference between the left and right hemi-faces, is a consequence of a different growth of the mandibular ramus. This difference may be due to the unilateral chewing, to occlusal interferences, or to muscle-bone dynamic alterations. All of them with great biomechanical importance. This morphological difference is aggravated during growth, since it not only causes an anomalous esthetic effect but, furthermore induces limitations on the chewing functional habits, temporomandibular disorders (TMD), or disorders of the ear, among others. Despite it has been demonstrated the relation between the malocclusion and the skeleton disproportion [1], and it has been simulated numerically the chewing biomechanics [2], currently the correction of facial abnormalities on children is made from a clinical point of view, exclusively. There are not computational simulations that consider the real morphology of the mandibular asymmetry, or the f...
Cambios dimensionales en la polimerización de las resinas
Jornada de Jóvenes Investigadores del I3A, 2018
Contemporary eating habits may cause malformations in children jaw, that are difficult to evaluat... more Contemporary eating habits may cause malformations in children jaw, that are difficult to evaluate and treat clinically. In this work, a computational methodology for the diagnosis and the treatment of this pathology is proposed. It combines porous-fibrous material models, medical devices and computational models of patients with facial asymmetries from the perspective of neuro-occlusal rehabilitation.
Journal of the Mechanical Behavior of Biomedical Materials, 2018
The periodontal ligament (PDL) is a porous and fibrous soft tissue situated around the tooth, whi... more The periodontal ligament (PDL) is a porous and fibrous soft tissue situated around the tooth, which plays a key role in the transmission of loads from the tooth to the alveolar bone of the mandible. Although several studies have tried to characterize its mechanical properties, the behaviour of this tissue is not clear yet. In this study, a new simulation methodology based on a material model which considers the contribution of porous and fibrous structure with different material model formulations depending on the effort direction is proposed. The defined material model was characterized by a non-linear approximation of the porous fibrous matrix to experimental results obtained from samples of similar species and was validated by rigorous test simulations under tensile and compressive loads. The global PDL response was also validated using the parameters of the characterization in a finite element model of full human canine tooth obtained by micro-tomography. The results suggest that the porous contribution has high influence during compression because the bulk modulus of the material depends on the ability of interstitial fluid to drain. On the other hand, the collagen fibres running along the load direction are the main responsible of the ligament stiffness during tensile efforts. Thus, a material model with distinct responses depending of the load direction is proposed. Furthermore, the results suggest the importance of considering 3D finite element models based of the real morphology of human PDL for representing the irregular stress distribution caused by the coupling of complex material models and irregular morphologies.
Minimally invasive complete rehabilitation of severe wear: one year follow up
Journal of Clinical and Experimental Dentistry, 2017