Oclusión basada en evidencia: rompiendo paradigmas / Occlusion based on evidence: breaking paradigms

La odontología basada en evidencias es una metodología que busca que las decisiones clínicas diarias que toman los profesionales en estomatología se encuentren fundamentadas en la evidencia científica, en ella se integran las experiencias clínicas, las necesidades, las preferencias del paciente y la evidencia clínicamente relevante más actual analizada por pares. Estos pilares son parte del proceso en la toma de decisiones para la atención al paciente. La odontología basada en evidencias surge de las exitosas experiencias obtenidas con el desarrollo e implementación de la medicina fundamentada en pruebas, al aplicar el método científico en la evaluación, planificación y toma de decisiones de las prestaciones sanitarias, sobre todo a través de los estudios controlados. En general, toda la práctica odontológica ha tenido grandes avances basados en evidencias, con hechos verídicos comprobados, pero los conceptos fundamentales de oclusión no han tenido una mejora cimentada en el conocimiento científico, prueba de ello es que se siguen ocupando teorías y conceptos de las filosofías de oclusión en la rehabilitación de muchos pacientes, seguimos creyendo en mitos y sofismas que no han podido ser demostrados. En esta revisión, demostramos los grandes avances en los conceptos de oclusión e invitamos a todos los odontólogos a romper los paradigmas de la oclusión antigua sin evidencias científicas y a utilizar las herramientas del método científico en la práctica clínica odontológica (AU)

Evidence-based dentistry is a strategy that seeks to ensure that the daily clinical decisions made by the dental professional are based on scientific evidence. It integrates the clinical experience of the dentist, the needs and preferences of the patient, and the most current relevant clinical evidence. All three are part of the decision-making process for patient care. Evidence-based dentistry arises from the successful experiences obtained with the development and implementation of evidence-based medicine, applying the scientific method in the evaluation, planning and decision-making of health benefits, especially through controlled studies. In general, all dental practice has had great advances based on evidence, with proven true facts, but the fundamental concepts of occlusion have not had an improvement based on scientific knowledge, proof of this is that theories and concepts continue to be used. of the philosophies of occlusion in patient rehabilitation, we follow myths and sophisms that have not been demonstrated, in this review, we demonstrate the great advances in the concepts of occlusion and we know all dentists to break the paradigms of the old occlusion without scientific evidence (AU)

[3D analysis of anatomical and functional parameters of TMJ and their correlation]. / Tsifrovoi 3D analiz anatomicheskikh i funktsional'nykh parametrov VNChS i ikh korrelyatsiya.

THE AIM OF THE STUDY: Was determination of TMJ anatomical and functional parameters in patients without clinical manifestations of TMJ dysfunction and analysis of possible relationships between them. MATERIAL AND METHODS: TMJ anatomical parameters of 25 volunteers (22-27 years old) without TMJ dysfunction, malocclusion and more than one tooth adentia were determined on CT scans and lab teeth scans: inclination of the distal slopes of the articular eminence (DS AE), height and width of the condyles, height of AE, inclination of the longitudinal axes of the condyles; as well as functional parameters of LJ movements: horizontal condylar inclination (HCI) during protrusion and laterotrusion, lateral condylar inclination during protrusion and laterotrusion, immediate side shift, incisor and canine guidance, and correlations between them were evaluated. RESULTS: The majority of the TMJ anatomical parameters are almost equal by mean values on the right and left sides. The main TMJ functional parameters on the right and left sides also have similar values but much higher variability, asymmetry and unpredictability. The existing anatomical asymmetry of the DS AE is compensated by articular discs, which makes HCI more symmetrical. CONCLUSION: Protrusion movements have a higher probability of reproduction by mechanical articulators while laterotrusion movements have a very low probability. The existence of relationship between the inclination of DS AE and HCI, between HCI and the incisor guidance, between the inclination of DS AE and the incisor guidance is questionable. The conducted research proves the weakness or complete absence of correlation between them.

Effect of laterotrusive occlusal scheme on chewing duration, external intercostal muscular activity, heart rate, and oxygen saturation.

Objective: To evaluate the effect of the laterotrusive occlusal scheme on chewing duration, external intercostal (EIC) electromyographic (EMG) activity, heart rate (HR), and oxygen saturation (OS) during different tasks in the upright seated position.Methods: Fifty young participants, 25 with canine guidance and 25 with group function, were included. Chewing duration, bilateral EIC EMG activity, HR, and OS were recorded during the following tasks: 1) chewing until swallowing threshold; 2) laterotrusive teeth grinding.Results: Chewing duration, bilateral EIC EMG activity, HR, and OS showed no significant differences between the two laterotrusive occlusal schemes during the tasks studied.Conclusion: These results suggest that chewing duration, EIC muscle activity, HR, and OS were not significantly influenced by the laterotrusive occlusal scheme. Therefore, when a modification of the laterotrusive occlusal scheme is needed during oral rehabilitation or orthodontic treatment, canine guidance or group function should not significantly change EMG activity of EIC muscles.

Agenesis of maxillary lateral incisors: diagnosis and treatment options

ABSTRACT Introduction: There are different possibilities of orthodontic planning for cases with congenital absence of maxillary lateral incisors. This subject divides the opinion of orthodontists and oral rehabilitation clinicians, due to the advantages and disadvantages of each treatment option, which may involve opening spaces for future implants and/or prosthetic restorations, or closing the spaces by positioning the maxillary canines in the place of lateral incisors. The correct diagnosis and careful evaluation of each patient allow to determine the best therapeutic approach. This paper discusses the main topics to be considered when planning these cases. Objectives: To evaluate the main aspects related to orthodontic treatment planning in cases of congenital absence of maxillary lateral incisors, to aid the decision-making, with clinical and scientific basis.

RESUMO Introdução: Existem diferentes possibilidades de planejamento ortodôntico para os casos que apresentam ausência congênita de incisivos laterais superiores. Esse é um assunto que divide a opinião de ortodontistas e reabilitadores orais, devido às vantagens e desvantagens de cada uma das opções de tratamento, as quais podem envolver a abertura de espaços para futuros implantes e/ou restaurações protéticas ou o fechamento dos espaços, com posicionamento dos caninos superiores no lugar dos incisivos laterais. O correto diagnóstico e uma criteriosa avaliação de cada paciente permitem determinar a melhor abordagem terapêutica. Nesse artigo, serão discutidos os principais tópicos a serem considerados no planejamento desses casos. Objetivos: Avaliar os principais aspectos relacionados ao planejamento do tratamento ortodôntico nos casos de ausência congênita de incisivos laterais superiores, de maneira a auxiliar nas tomadas de decisão, com embasamento clínico e científico.

An evaluation of the stress effect of different occlusion concepts on hybrid abutment and implant supported monolithic zirconia fixed prosthesis: A finite element analysis.

PURPOSE: The aim of this study is to evaluate the effects of canine guidance occlusion and group function occlusion on the degree of stress to the bone, implants, abutments, and crowns using finite element analysis (FEA). MATERIALS AND METHODS: This study included the implant-prosthesis system of a three-unit bridge made of monolithic zirconia and hybrid abutments. Three-dimensional (3D) models of a bone-level implant system and a titanium base abutment were created using the original implant components. Two titanium implants, measuring 4 × 11 mm each, were selected. The loads were applied in two oblique directions of 15° and 30° under two occlusal movement conditions. In the canine guidance condition, loads (100 N) were applied to the canine crown only. In the group function condition, loads were applied to all three teeth. In this loading, a force of 100 N was applied to the canine, and 200-N forces were applied to each premolar. The stress distribution among all the components of the implant-bridge system was assessed using ANSYS SpaceClaim 2020 R2 software and finite element analysis. RESULTS: Maximum stress was found in the group function occlusion. The maximum stress increased with an increase in the angle of occlusal force. CONCLUSION: The canine guidance occlusion with monolithic zirconia crown materials is promising for implant-supported prostheses in the canine and premolar areas.

Pressure Algometry Evaluation of Two Occlusal Splint Designs in Bruxism Management-Randomized, Controlled Clinical Trial.

The aim of this pilot study was to evaluate the short-term effectiveness of two different occlusal devices and their impact on the pressure pain threshold (PPT) values among patients who reported to the Dental Prosthetics Outpatient Clinic of Pomeranian Medical University (Szczecin, Poland) and who were diagnosed with probable bruxism. Two groups were formed (A and B) to which patients were assigned randomly. Each group used a different occlusal splint for bruxism management. The occlusal appliance by Okeson, or the bimaxillary splint, was used overnight by each patient for 30 days of the study. The PPT was measured twice, at the first visit and after 30 days of using each occlusal device, with Wagner Paintest FPX 25 algometer. Bruxism was diagnosed based on data from the patient's medical history and from the physical examination. Nocturnal Bruxism Criteria according to the International Classification of Sleep Disorders (Third Edition) was used for the patient's evaluation. Results: similar pain factor (PF) reduction was observed in both the examined groups, regardless of the device used; canine guidance and no guidance were similarly effective in terms of increasing pain resilience.

Complete Denture Occlusion: Best Evidence Consensus Statement.

PURPOSE: The occlusal scheme required for an edentulous patient is controversial. The purpose of this Best Evidence Consensus Statement was to evaluate the existing complete denture literature related to occlusal schemes. MATERIALS AND METHODS: A literature search was limited to Meta-analyses, Systematic Reviews (SR), Randomized Controlled Studies (RCT) and Clinical Trials. Key Words were: Complete dentures, occlusion, harm; Complete dentures, occlusion alveolar bone loss; Complete dentures, occlusion, stability; Complete dentures, occlusion. Additional related articles were culled from the authors' library and reference lists in the articles found in the PubMed searches. RESULTS: Of the 165 articles that met the initial search criteria, 34 related to the focus questions and were evaluated and rated. CONCLUSIONS: There is strong support that the average denture patient, with good residual ridges and no neuromuscular problems, will function adequately with a properly fabricated complete denture regardless of the occlusal scheme. There is neither strong support for or against bilateral balanced occlusal schemes as it relates to patient satisfaction, preference or chewing ability. There is some support for increased alveolar bone loss with complete dentures that have a non-balanced occlusion. There is a need for bilateral balanced occlusal schemes for patients presenting with loss of stability and retention as a result of their presenting conditions (PDI III and IV).

Occlusion time, occlusal balance and lateral occlusal scheme in subjects with various dental and skeletal characteristics: A prospective clinical study.

OBJECTIVES: To analyse occlusion time, occlusal balance and lateral occlusal scheme in subjects with various dental and skeletal characteristics. METHODS: A total of 132 subjects (50 males and 82 females) seeking orthodontic treatment were included in this prospective study. Using the T-Scan III version 7.0 (Tekscan Inc, South Boston, MA, USA), the occlusion time, occlusal balance and lateral occlusal schemes were recorded and compared with gender, Angle's occlusal classification, overjet, overbite, space analysis, skeletal and transverse relations. ANOVA, t test and contingency tables analyses were performed. Statistical significance was set at P < .05. RESULTS: Occlusion time was significantly shorter in subjects with balanced occlusion (0.18 seconds, P < .001), Class I normal occlusion (0.35 seconds, P = .028) and Class I skeletal profile (0.37 seconds, P = .002). Occlusion time was significantly longer in subjects with decreased overjet (0.60 seconds, P = .003). There were significant associations between the distribution of occlusal balance and Angles' classes of occlusion, skeletal relationship, overjet, overbite and space analysis (P < .05). Lateral occlusal schemes were only associated with Angle's classes of occlusion and skeletal relationship (P < .05). CONCLUSIONS: Patients with Class I occlusion showed the least occlusion time, the most balanced occlusion and a higher frequency of canine guidance. Nonetheless, potentially balanced occlusion and group function were highly prevalent in all groups; therefore, ideal occlusion must be considered an ideal to inspire and aim for, but cannot be considered an essential requirement of every dental treatment.

Awake teeth grinding in participants with canine guidance or group function: Effect on diaphragm EMG activity, heart rate, and oxygen saturation.

Objective: To compare the effect of canine guidance or group function on diaphragm activity, heart rate, and oxygen saturation during awake teeth grinding at different body positions. Methods: Fifty healthy participants, 25 with canine guidance and 25 with group function, were included. Bilateral electromyographic (EMG) recordings of the diaphragm (DIA) during awake teeth grinding were performed in standing, seated upright, and right lateral decubitus positions. Simultaneously, heart rate and oxygen saturation were measured. Results: EMG activity of the DIA muscle was similar in the working side and non-working side between participants with canine guidance and group function in the different body positions studied. The heart rate and oxygen saturation showed no significant differences between the two groups. Conclusion: EMG activity of the DIA muscle, the heart rate, and oxygen saturation during teeth grinding are not significantly influenced by the type of laterotrusive occlusal scheme.

Prospective clinical study of bilateral balanced occlusion (BBO) versus canine-guided occlusion (CGO) in complete denture wearers.

OBJECTIVES: Previous studies have often discussed occlusal concepts for complete dentures without formulating a recommendation. Various options are available, the most common ones being canine-guided occlusion (CGO) and bilateral balanced occlusion (BBO). We designed a prospective randomized study to compare these two schemes with the goal of formulating a recommendation. MATERIALS AND METHODS: Forty patients could be evaluated. In a crossover design, they were randomized to a CGO>BBO group and a BBO>CGO group, each starting out by wearing their dentures with the first occlusal scheme for 3 months, followed by a first investigator- and patient-centered assessment. Then, each patient was transitioned to the other occlusal scheme by replacing the denture setup in the dental laboratory, followed by another 3 months of intraoral use and a second assessment. Wilcoxon-Mann-Whitney and marginal homogeneity tests were used for statistical analysis. RESULTS: All statistically significant differences favored the CGO concept. Based on patient ratings, the CGO>BBO group preferred its esthetics (p = 0.02) and the BBO>CGO group its mandibular retention (p = 0.05), phonetics (p = 0.03), and masticatory function (p = 0.01). Based on investigator assessments, maxillary denture retention was found to significantly improve among the BBO>CGO patients after transition to CGO (p = 0.01). CONCLUSIONS: Within the limitations of this study, canine guidance can be recommended as a comfortable alternative to bilateral balanced occlusion for complete dentures. CLINICAL RELEVANCE: This recommendation can reduce the time requirements for the fabrication of complete dentures in dental laboratories.

Effect of different lateral occlusion schemes on peri-implant strain: A laboratory study.

PURPOSE: This study aims to investigate the effects of four different lateral occlusion schemes and different excursions on peri-implant strains of a maxillary canine implant. MATERIALS AND METHODS: Four metal crowns with different occlusion schemes were attached to an implant in the maxillary canine region of a resin model. The included schemes were canine-guided (CG) occlusion, group function (GF) occlusion, long centric (LC) occlusion, and implant-protected (IP) occlusion. Each crown was loaded in three sites that correspond to maximal intercuspation (MI), 1 mm excursion, and 2 mm excursion. A load of 140 N was applied on each site and was repeated 10 times. The peri-implant strain was recorded by a rosette strain gauge that was attached on the resin model buccal to the implant. For each loading condition, the maximum shear strain value was calculated. RESULTS: The different schemes and excursive positions had impact on the peri-implant strains. At MI and 1 mm positions, the GF had the least strains, followed by IP, CG, and LC. At 2 mm, the least strains were associated with GF, followed by CG, LC, and IP. However, regardless of the occlusion scheme, as the excursion increases, a linear increase of peri-implant strains was detected. CONCLUSION: The peri-implant strain is susceptible to occlusal factors. The eccentric location appears to be more influential on peri-implant strains than the occlusion scheme. Therefore, adopting an occlusion scheme that can reduce the occurrence of occlusal contacts laterally may be beneficial in reducing peri-implant strains.

Conceitos importantes sobre o dente canino / Important aspects of canine tooth

A Odontologia Restauradora é fundamentada numa tríade: função, biologia e estética. Muitas vezes, durante o planejamento estético, nos preocupamos com a forma, harmonia, coesão facial, cor e posição principalmente dos dentes Incisivos centrais e laterais. O canino é um dente muito importante também para todos esses efeitos e responsável pela curvatura do sorriso, dando o início do efeito paralaxe do corredor bucal. O mau posicionamento desse dente no arco pode comprometer a estética e função, afetando principalmente a guia canina. É importante lembrar que esse dente protege mutualmente o arco dentário anterior e posterior e alguns conceitos são importantes para estabelecer sua forma correta e sua posição ideal na arcada.

Restorative dentistry is based on the triad: function, aesthetics, and biology. During treatment planning, we often care about shape, facial harmony, color and position, especially when it comes to central and lateral incisors. however the canine teeth is also very important since impact all these factors. In addition canine teeth are also responsible for the curvature of the smile, initiating the buccal corridor. Poor positioning of the canines may compromise both aesthetic and function, with great impact over canine guidance. It is important to notice that this tooth protects the maxillary and mandibular arches, and some aspects must be observed in order to achieve its proper shape and position.

A prospective cross-over study to evaluate the effect of two different occlusal concepts on the masseter muscle activity in implant-retained mandibular overdentures.

BACKGROUND: The purpose of this prospective cross-over study is to evaluate the effect of bilateral balanced occlusion and canine guidance occlusion on the masseter muscle activity using implant-retained mandibular overdentures. METHODS: After evaluation of 12 completely edentulous patients using cone beam computed tomography (CBCT), mucoperiosteal flaps were reflected exposing the mandibular interforaminal region. Two implants were placed in the interforaminal region for each of the 12 patients. After a healing period of 3 months, acrylic maxillary complete dentures and mandibular overdentures were fabricated with bilateral balanced occlusion for 6 patients and canine guidance occlusion for the other 6 patients. Electromyographic evaluation of the masseter muscles, during clenching on a silicon index and chewing peanuts and cake, was conducted on the patients after using their dentures for 4 weeks. Each occlusion concept was then converted into the other concept using the same dentures, and the procedure of evaluation was repeated after 4 weeks. The recordings were analyzed statistically using Wilcoxon signed ranks test. p < 0.05 was considered statistically significant. RESULTS: The highest electromyographic activity of the masseter muscles was recorded during clenching on a preformed silicon index followed by chewing peanut then cake for both occlusal concepts. The recordings of the masseter muscle associated with canine guidance occlusion were higher than bilateral balanced occlusion but with no statistically significant difference except between the right masseter muscles during clenching (p = 0.042*). CONCLUSIONS: Both bilateral balanced occlusion and canine guidance occlusion can be used successfully in implant-retained mandibular overdentures without affecting masseter muscle activity.

Reconstrução da guia canina em ouro: relato de caso clínico / Reconstruction of the canine guide in gold: a case report

Este relato visa mostrar a reconstituição da guia canina em um paciente com oclusão em balanceio bilateral, situação caracterizada pela ausência de desoclusão dos dentes posteriores, nas movimentações laterais da mandíbula. Com o objetivo de preservar estes dentes e suas estruturas periodontais, foram confeccionadas restaurações de ouro inciso-palatinas nos caninos superiores, sem comprometimento da estética, para que os mesmos pudessem atuar de forma alternada na desoclusão dos molares e pré-molares, durante as excursões mandibulares. O procedimento restaurador teve acompanhamento fotográfico e radiográfico ao longo de 19 anos, concluindo-se que o procedimento restaurador contribuiu para a preservação dos dentes posteriores e suas estruturas de suporte, eliminando as forças oclusais oblíquas que antes incidiam sobre estes elementos, devido à inexistência da guia canina que provocava perda óssea vestibular e consequente retração gengival. (AU)

This report aims to show the reconstitution of canine guidance in a patient with bilateral balanced occusion, a situation characterized by the absence of deocclusion of posterior teeth, the lateral shift of the mandible. In order to preserve these teeth and their periodontal structures, incisal-palatines gold restorations were placed on maxillary canines, without compromising aesthetics, so that they could act alternately on deocclusion molars and premolars, during mandibular excursions. The restorative procedure had photographic and radiographic follow-up over 19 years, concluding that the restorative procedure contributed to preserve the posterior teeth and their supporting structures, eliminating the oblique occlusal forces than before focused on these elements, due to the lack of canine guidance, which caused buccal bone loss and consequent gingival recession. (AU)

Immediate placement and functional loading of implants on canine with fixed partial denture for a patient having canine protected occlusion: a case report.

Conventional implant protocols required a load-free healing period of three to six months between placement and functional loading of the implants. Many efforts have been made to minimize the duration of treatment time. Several literatures have documented immediate function with provisional or definitive prosthesis within a week of the placement in response to these demands. In addition, immediate implant placement has advantages such as shortened treatment time and preservation of soft tissue architectures. This article presents immediate implant placement into fresh extraction sockets followed by functional immediate loading with provisional prosthesis on canine and premolars for a patient having canine protected occlusion.

Masticatory afficiency in denture wearers with bilateral balanced occlusion and canine guidance

The maintenance of masticatory function is especially important for patients wearing complete dentures due to their limitations. Thus, the bilateral balanced occlusal concept is used to achieve greater masticatory efficiency. However, a critical review of the literature reveals that there is not sufficient scientific evidence to support bilateral balanced occlusion as the most appropriate occlusal concept in complete dentures. Therefore, the aim of this study was to evaluate the masticatory efficiency in complete dentures wearers with bilateral balanced occlusion and canine guidance. A double-blinded controlled crossover clinical trial was conducted. The sample was composed by 24 edentulous patients who wore sets of complete dentures with both occlusal concepts during equal periods of 3 months. Objective data were collected through the masticatory efficiency test performed by the colorimetric method with the beads, in which capsules of a synthetic material enclosing fuchsine-containing granules were used. Subjective data were recorded by patient's ratings of their chewing function. No significant statistical difference was found for masticatory efficiency (p=0.095) between the two occlusal concepts studied. The results suggest that bilateral balanced occlusion does not improve the masticatory efficiency in complete denture wearers.

A manutenção da função mastigatória tem importância especial em pacientes portadores de prótese total devido às limitações inerentes a esse tipo de prótese. Nesse contexto, a oclusão balanceada bilateral (OBB) é empregada com o intuito de obter-se uma maior eficiência mastigatória. Entretanto, analisando-se a literatura criticamente, observa-se que não existem evidências científicas suficientes que suportem a aplicação da OBB como conceito oclusal ideal em prótese total (PT). Assim, o presente trabalho teve o objetivo de verificar se pacientes portadores de PT dupla com OBB apresentam maior eficiência e capacidade mastigatória que aqueles com desoclusão com guia canino (DGC). Com esse intuito, realizou-se um ensaio clínico controlado duplo-cego do tipo crossover. A amostra foi composta de 24 pacientes portadores de prótese total dupla, onde todos fizeram uso de ambos os conceitos oclusais por períodos iguais de 3 meses. A avaliação da eficiência mastigatória foi realizada através do método colorimétrico com o uso de cápsulas mastigatórias. Não se encontrou diferença estatística significativa para a eficiência (p=0,0952) entre os dois conceitos oclusais estudados. Dessa forma, pode-se concluir que usuários de PT dupla com OBB não apresentam maior eficiência mastigatória que aqueles com DGC.