Placental apoptosis increased by hypoxia inducible factor-1 stabilization is counteracted by leptin†.

During pregnancy, apoptosis is a physiological event critical in the remodeling and aging of the placenta. Increasing evidence has pointed toward the relevance of hypoxia as modulator of trophoblast cell death. Previous reports have shown that leptin, a placental cytokine, promotes cell survival in both cell culture and placental explant models. The aim of this work is to establish the role of leptin in apoptosis under hypoxic condition in trophoblast cells. In this study, we evaluated the effect of cobalt chloride, a hypoxia mimicking agent that stabilizes the expression of hypoxia-inducible factor-1 alpha, on Swan-71 and human placental explants. Hypoxia chamber was also used to generate 2% oxygen. Apoptosis was determined by the presence of apoptotic nucleus, fragmentation of DNA and Caspase-3 and PARP-1 cleavage. The pro-apoptotic proteins BAX, BID, BAD, and BAK and the anti-apoptotic effectors BCL-2, B-cell lymphoma-extra-large, and myeloid cell leukemia-1 were also analyzed. We found that hypoxia-inducible factor-1 alpha stabilization increased the appearance of apoptotic nucleus, fragmentation of DNA, and Caspase-3 and PARP-1 cleavage. Hypoxia mimicking conditions enhanced the expression of pro-apoptotic effectors BAX, BID, BAD, and BAK. Hypoxia-inducible factor-1 alpha stabilization also downregulated the level of BCL-2, B-cell lymphoma-extra-large, and myeloid cell leukemia-1. All these apoptotic parameters changes were reversed with leptin treatment. Moreover, we showed that leptin action on apoptosis modulation involves PI3K and MAPK signaling pathways. Obtained data demonstrate that hypoxia-inducible factor-1 alpha stabilization induces apoptosis in human placenta and leptin counteracts this effect, reinforcing its role as a survival cytokine.

Lysine methyltransferase 2 plays a key role in the encystation process in the parasite Giardia lamblia.

Histone post-translational modifications are extensively studied for their role in regulating gene transcription and cellular environmental adaptation. Research into these modifications has recently begun in the protozoan parasite Giardia lamblia, focusing on histone-modifying enzymes and specific post-translational changes. In the transformation from the trophozoite to the cyst form in the life cycle of this parasite, significant morphological and genetic alterations occur, culminating in the synthesis of cyst wall proteins responsible for forming the protective cyst wall. It has been previously demonstrated that histone deacetylation is required during encystation and that the enzyme lysine methyltransferase 1 is involved in the upregulation of encystation. Our study aims to extend the analysis to lysine methyltransferase 2 (GlKMT2) function. For this, two constructs were generated: one that downregulate the expression of GLKMT2 via antisense (glkmt2-as transgenic cells) and the other overexpressing GlKMT2 (glkmt2-ha transgenic cells). We found that the glktm2-as transgenic cells showed an arrest in progress at the late encystation stage. Consequently, the number of cysts produced was lower than that of the control cells. On the other hand, we found that the overexpression of GlKMT2 acts as a negative mutant of the enzyme. In this way, these glktm2-ha transgenic cells showed the same behavior during growth and encystation as glkmt2-as transgenic cells. This interplay between different enzymes acting during encystation reveals the complex process behind the differentiation of the parasite. Understanding how these enzymes play their role during the encystation of the parasite would allow the design of inhibitors to control the parasite.

Metodologias ativas no ensino da Prótese Parcial Removível durante a COVID-19: um relato de experiência da Universidade Federal da Paraíba / Metodologías activas em la enseñanza de Prótesis Parcial Removible durante laCOVID-19: relato de experiencia de la Universidade Federal da ParaíbaResumen / Active methodologies in teaching the Removable Partial Denture course during COVID-19: an experience report

Este estudo objetiva apresentar a experiência do componente curricular Prótese Parcial Removível (PPR) da Universidade Federal da Paraíba com a implementação de metodologias ativas, como gamificação, sala de aula invertida e case-based learning(CBL), no ensino à distância, visando sedimentar o aprendizado quanto ao planejamento de arcos parcialmente desdentados. As atividades foram realizadas de forma síncrona e assíncrona, utilizando como casos os esquemas bidimensionais e fotografias de arcosparcialmente desdentados, baseando-se no conceito de sala de aula invertida, no qual os alunos apresentavam os casos e os professores atuavam como mediadores nas discussões. Observou-se um grande engajamento e participação ativa dos alunos na construção do seuconhecimento. A inserção dessas metodologias no ensino remoto funcionou como um eixo motivacional para os alunos, fomentando a aprendizagem e estimulando o desenvolvimento de competências no planejamento em PPR previamente ao atendimento clínico (AU).

Este estudio tiene como objetivo presentar la experiencia del componente curricular Prótesis Parcial Removible de la Universidade Federal da Paraíba con la implementación de metodologías activas, como gamificación, aula invertida y aprendizaje basado en casos, en educación a distancia, con el objetivo de consolidar el aprendizaje sobre la planificación de arcadas parcialmente edéntulas. Las actividades se realizaron de forma sincrónica y asincrónica, utilizando diagramas bidimensionales y fotografías de arcos parcialmente edéntulos como casos, basados en el concepto de aula invertida, en la que los estudiantes presentaban los casos y los docentes actuaban como mediadores en las discusiones. Hubo un gran compromiso y participación activa de los estudiantes en la construcción de su conocimiento. La inclusión de estas metodologías en la enseñanza a distancia funcionó como eje motivacional de los estudiantes, favoreciendo el aprendizaje y estimulando el desarrollo de habilidades en la planificación de la Prótesis Parcial Removible previa a la atención clínica (AU).

This study aims to present the experience of RPD course at the Universidade Federal da Paraíba using active methodologies such as gamification, flipped classroom and case-based learning (CBL) in distance learning, aiming to consolidate learning in planningpartially edentulous arches. Activities were carried out synchronously and asynchronously using two-dimensional schemes and photographs of partially edentulous arches as "cases" and based on the concept of the flipped classroom, where students presented the cases and the teachers acted as mediators in the discussions. Excellent engagement and active participation of students in their knowledge construction were observed. The insertion of these methodologies in remote teaching acted as a motivational axis for the students, promoting learning and stimulating development of competences in RPD planning prior to clinical care (AU).

Integração dos componentes curriculares Escultura Dental e Prótese Parcial Removível no desenvolvimento de material didático auxiliar para a pré-clínica / Integración de los componentes curriculares Escultura Dental y Prótesis Parcial Removible en el desarrollo de material didáctico auxiliar para el preclínico / Integration of Dental Sculptureand Removable Partial Denture courses in developing instructional material for pre-clinical use

O objetivo deste relato de experiência foi integrar os componentes curriculares Escultura Dental e Prótese Parcial Removível por meio da confecção de macromodelos com nichos em dentes anteriores e posteriores a serem usados como material didático auxiliar.A metodologia teve abordagem descritiva. Foram confeccionados macromodelos em cera dos seguintes elementos dentários: caninos superiores e inferiores, pré-molar superior e molares superiores e inferiores. Em seguida, nichos foram preparados nos elementos,reproduzindo as características da etapa de Preparo de Boca Tipo II ou Protético. Macromodelos com as características individuais de nichos oclusais simples e duplo (interdental) em dentes posteriores foram obtidos, bem como com nichos em cíngulos, tanto confecionados por desgaste como por acréscimo. Diante do conhecimento da anatomia dental e a habilidade manual desenvolvidos na Escultura Dental, os macromodelos confeccionados permitiram uma melhor visualização das características morfológicas dos nichos,sendo considerado um recurso complementar no processo ensino-aprendizagem em Prótese Parcial Removível (AU).

El objetivo de este relato de experiencia fue integrar los componentes curriculares Escultura Dental y Prótesis Parcial Removible mediante la creación de macromodelos con nichos en dientes anteriores y posteriores para ser utilizados como material didáctico auxiliar. La metodología tuvo un enfoque descriptivo. Se realizaron macromodelos en cera de los siguientes dientes: caninos superiores e inferiores, premolares superiores y molares superiores e inferiores. A continuación, se prepararon nichos en los elementos, reproduciendo las características de la etapa de Preparación de la Boca Tipo II o Prótesis. Se obtuvieron macromodelos con las características individuales de nichos oclusales simples y dobles (interdentales) en dientes posteriores, así comonichos en cingulados, ambos creados por desgaste y adición. Dado el conocimiento de la anatomía dental y la habilidad manual desarrollada en la Escultura Dental, los macromodelos realizados permitieron una mejor visualización de las características morfológicas de los nichos, considerándose un recurso complementario en el proceso de enseñanza-aprendizaje en Prótesis Parcial Removible (AU).

The objective of this experience report was to integrate the curricular components of Dental Sculpture and Removable Partial Dentures through the creation of macromodels with rest seat in anterior and posterior teeth to be used as auxiliary teaching material. The methodology had a descriptive approach. Wax macromodels were made of the following teeth: upper and lower canines, upper premolar and upper and lower molars. Next, rest seats were prepared in the elements, reproducing the characteristics of the Type II or Prosthetic Mouth Preparation stage. Macromodels with the individual characteristics of single and double (interdental) occlusal rest seats in posterior teeth were obtained, as well as rest seats in cingulum, both created by wear and with composites. Given the knowledge of dental anatomy and the manual skill developed in Dental Sculpture, the macromodels made enabled better visualization of the morphological characteristics of the rest seats, being considered a complementary resource in the teaching-learning process in Removable Partial Prosthesis (AU).

Combinando estratégias de aprendizagem para o desenvolvimento de habilidades e competências na Prótese Parcial Removível pré-clínica: um relato de experiência / Combining learning strategies for developing abilities and competencies in a preclinical Removable Partial Denture course: an experience report

O uso da metodologia ativa no ensino da Odontologia é recomendado nas Diretrizes Curriculares Nacionais, com a finalidade de desenvolver habilidades e competências, assim como de estimular a capacidade reflexiva dos egressos. Em Prótese Parcial Removível (PPR), alguns estudos apontam os benefícios do método centrado no aluno, utilizando diferentes estratégias, como Problem-Based Learning (PBL), Case-Based Learning (CBL) e Team-Based Learning (TBL) com resultados positivos no processo ensino-aprendizagem. Este artigo tem como objetivo relatar a experiência do uso de metodologias ativas como o CBL, a Sala de Aula Invertida e a estratégia do Brainstorming na disciplina de Prótese Parcial Removível da Universidade Federal da Paraíba, estimulando o desenvolvimento do pensamento crítico do aluno no planejamento de arcos parcialmente desdentados desde a fase pré-clínica. Como produto dessa mudança na estratégia pedagógica, desenvolveram-se materiais instrucionais como um checklist de perguntas e um fluxograma que foram implementados como ferramentas facilitadoras no processo ensino-aprendizagem durante as práticas de laboratório. A adaptação de estratégias de ensino com participação ativa dos estudantes pode ser útil na verificação das dificuldades durante o planejamento, as quais podem ser solucionadas previamente aos atendimentos de pacientes nas clínicas. Os materiais instrucionais desenvolvidos na disciplina podem auxiliar os professores de Odontologia a refletir sobre diferentes formas de metodologias no ensino da PPR e inserir o aluno no processo de construção do seu conhecimento (AU).

Active methodologies in dental education have been highly recommended by the National Curricular Guidelines in developing students' abilities and competency, and directly impact on the reflective capacity of new professionals. Some studies on Removable Partial Dentures (RPD) have pointed out benefits of the student- centered method by using different strategies such as Problem-Based Learning (PBL), Case- Based Learning (CBL) and Team-Based Learning (TBL), with positive results in the teaching and learning processes. This article aims to report the experience of using active methodologies such as CBL, Inverted Classroom and Brainstorming techniques as a strategy in the RPD Preclinical Course of the Federal University of Paraíba, focusing on the development of students' critical thinking for planning partial edentulous arches. As a result of this change, instructional materials such as a checklist of questions and a flowchart were developed and have started to be implemented as important tools during the laboratory classes. Adapting teaching strategies with the active participation of students can be a valuable tool to verify difficulties during prosthesis planning. As a result, it can improve self-confidence in determining the mechanical components prior to clinical care. The instructional materials developed can help professors to reflect on different forms of methodologies in RPD teaching and insert students in their own knowledge construction (AU).

Inestabilidad hemodinámica en obstetricia / Hemodynamic inestability in obstetric patient

The hemodynamic instability in the pregnant patient is a challenge for the treating team, due to the physiological peculiarities of her condition and the emotional impact of her care. Considering the increase in the mortality of pregnant women worldwide in developed countries due to múltiple factors associated with an inadequate level of care, anesthesiologists have an essential role within this team. Early recognition and timely treatment of a pregnant or postpartum patient is required. The evaluation of the hemodynamic status only with the clinic in changing situations may be insufficient in the obstetric patient for an adequate management, especially in pathophysiological conditions and with the impact of the pharmacological action of anesthesia. Therefore, monitoring at the patient's bedside, mainly through monitoring of cardiac output (CO), myocardial response and volemia status with minimally invasive cardiac output monitors, cardiac and pulmonary ultrasound evaluation allow a management that has an impact on survival.

La inestabilidad hemodinámica en la paciente gestante constituye un desafío para el equipo tratante, por las peculiaridades fisiológicas que ofrece su condición y por el impacto emocional que genera su atención. Considerando el aumento de la mortalidad de la embarazada a nivel mundial en países desarrollados debido a factores múltiples asociados a un nivel de cuidados no adecuados, es que los anestesiólogos cumplen un rol fundamental dentro de este equipo. Se requiere la detección precoz y tratamiento oportuno de una paciente gestante o puérpera. La evaluación del estado hemodinámico solo con la clínica en situaciones cambiantes puede ser insuficiente en la paciente obstétrica para un adecuado enfrentamiento, especialmente en condiciones fisiopatológicas y con impacto de la acción farmacológica de la anestesia. Es por esto que la monitorización al lado del paciente, principalmente a través de la vigilancia del gasto cardíaco (GC); la respuesta miocárdica y el estado de la volemia con monitores de gasto cardíaco mínimamente invasivos; la evaluación ecográfica cardíaca y pulmonar permiten un enfrentamiento que impacta en la sobrevida.

Avaliação da correlação entre o grau de instruções e qualidade de higiene de usuários de próteses totais com a presença de estomatite protética / Correlation between the level of instructions and the quality of hygiene of complete denture wearers with presence of denture stomatitis

Objetivo: Avaliar a correlação entre tempo de uso da prótese, idade do paciente, grau de instrução dos pacientes e qualidade observada da higiene das próteses totais com a presença de estomatite protética. Material e método: Foi aplicado questionário para levantamento dos dados. A presença de biofilme na superfície interna das próteses totais superiores foi inspecionada visualmente. O exame clínico da região palatina nos pacientes foi realizado para avaliar a presença de estomatite protética. Os dados foram analisados por meio dos testes de Correlação de Spearman (tempo de uso da prótese e idade do paciente x estomatite protética), U de Mann-Whitney (gênero e frequência de escovação x inflamação da mucosa; uso contínuo da prótese e instruções do cirurgião-dentista x presença de estomatite protética; instrução do cirurgião-dentista x necessidade de consultas periódicas) e Tau-B de Kendall (higiene da superfície interna da prótese x estomatite protética). Todas as análises foram feitas considerando- se α=5%. Resultados: A maioria dos pacientes não tira a prótese para dormir (91,10%) e relata higienizar esta três vezes ao dia (44,40%). Porém, a higiene das próteses foi considerada precária (53,30%). Nenhum dos fatores investigados relacionados aos relatos dos pacientes influenciou na presença/severidade da estomatite (p>0,05). Entretanto, a higiene observada internamente nas próteses foi inversamente proporcional à presença/severidade da estomatite (p<0,001). Conclusões: Não foi observada correlação entre idade, tempo de uso da prótese, grau de instrução dos pacientes e estomatite protética. Porém, a qualidade observada da higiene das próteses foi considerada precária, estando negativamente relacionada com a prevalência da estomatite protética.

Objective: To evaluate the correlation between patients denture using time, age, degree of instruction and observed quality of complete dentures with the prevalence of denture stomatitis. Material and method: It was applied a questionnaire to data collection. The biofilm in the inner surface of superior dentures were accessed visually. A clinical examination of the palatal area of the patients was performed to classify the presence of denture stomatitis. Data were analyzed by the following tests: Spearman correlation (time of prosthesis usage and patient age x denture stomatitis), Mann-Whitney U (patient gender and prosthesis hygiene x mucosal inflammation; continuous usage of prosthesis and dentist instructions x denture stomatitis; dentist instructions x periodic consult needs) and Kendall Tau-B (hygiene of internal surface of prosthesis x denture stomatitis). All analyses were done considering α=5%. Results: Most patients relate to do not remove the dentures before sleeping (91.10%) and to clean up them three times a day (44.40%), however, the overall hygiene of the dentures was considered poor (53.30%). None of the factors related to patients relates influences stomatitis presence/severity (p>0.05). However, it was found an inverse correlation between the denture surface hygiene and denture stomatitis (p<0.001). Conclusion: It was not found any correlation among patients age, denture using time and degree of instruction with denture stomatitis. However, the overall hygiene of the dentures investigated, which was considered to be poor, were negatively correlated with the denture stomatitis prevalence.

Resistance to impact of cross-linked denture base biopolymer materials: effect of relining, glass flakes reinforcement and cyclic loading.

AIMS: The effect of reinforcement and cyclic loading on the resistance to impact (RI) of denture base biopolymer materials was evaluated using Charpy (C) and falling-weight (FW) impact tests. METHODS: Bar-shaped (60×6×2mm(3)) and denture-shaped specimens (2mm) for the C and FD tests, respectively, were prepared with Lucitone 550 (L) and Vipi Wave (V) and relined (2mm) using the same material or the autopolymerizing relining resins Tokuyama Rebase II (T) and Ufi Gel Hard (U). Bulk specimens (60×6×4mm(3)) of all materials (L, V, T and U) were also prepared and tested. To evaluate the effect of reinforcement, glass flakes were added to the powder of the relining resins T and U (5% by weight). Half of bar-shaped (n=320) and half of the denture-shaped specimens (n=480) were subjected to cyclic loading (10,000 cycles) before the impact tests. RESULTS: Data were analyzed by one-way ANOVAs (α=0.05) and revealed that the RI of L and V were comparable and higher than those of U and T. Compared to L and V, the RI was increased by relining with T and decreased by relining with U. When relining was made using the same material (L and V) the RI was maintained. Flexural cyclic loading and the incorporation of glass flakes into the resins T and U did not cause any significant alteration in the RI. A high correlation between results from C and FW tests was observed (r=0.8854). CONCLUSION: Relining may exert effects on the RI of L and V denture base resins, which vary according to the relining material used. The high correlation between C and FW, suggests that the Charpy test, using bar-shaped specimens, can be a simple and reliable method for evaluating factors that may influence the RI of denture base polymers.

Maxillary rehabilitation using fixed and removable partial dentures with attachments: a clinical report.

Despite requiring dental crown preparation and possible root canal treatment, besides the difficulty of clinical and laboratory repairs, and financial burden, the association between fixed (FPD) and removable partial dentures (RPD) by means of attachments is an important alternative for oral rehabilitation, particularly when the use of dental implants and FPDs is limited or not indicated. Among the advantages of attachment-retained RPDs are the improvements in esthetics and biomechanics, as well as correction of the buccal arrangement of anterior teeth in Kennedy Class III partially edentulous arches. This article describes the treatment sequence and technique for the use of attachments in therapy combining FPD/RPD.

Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resin.

OBJECTIVE: In this study, the effect of relining and surface treatment on the impact strength (IS) of a heat-polymerising denture base acrylic resin (Lucitone 550-L) was evaluated. MATERIALS AND METHODS: Rectangular bars of L were made (60 x 6 x 2 mm) and relined (2 mm) with the relining resins Ufi Gel Hard (UH) and Tokuso Rebase Fast (TR). Specimens relined with L and intact L, TR and UH specimens were also made (60 x 6 x 4 mm), for comparison. Before relining, the L surface was left untreated or wetted with methyl methacrylate monomer and/or the bonding agents (BA) supplied by manufacturers of the reline resins. V-notches were machined at the midpoint of the length of all specimens. The notches were made either across the width (Nw) or across the thickness of the specimens (Nth). The Charpy impact test was performed using a 0.5-J pendulum, which had been specially designed and constructed. Data were analysed separately for each notch position using one-way analysis of variance and Tukey honestly significant difference post-hoc test (p = 0.05). RESULTS: The IS of L was similar to that of L/L. For the Nw notch, treating the denture base L with TR BA and relining with TR reline material produced the highest IS. CONCLUSION: The IS of specimens made from heat polymerising acrylic resin Lucitone 550 was increased after relining using the hard chairside reline resin TR with its proprietary BA.

Hardness and surface roughness of reline and denture base acrylic resins after repeated disinfection procedures.

STATEMENT OF PROBLEM: Microwave irradiation and immersion in chemical solutions have been recommended for denture disinfection. However, the effect of these procedures on the surface characteristics of denture base and reline resins has not been completely evaluated. PURPOSE: The purpose of this study was to evaluate the effect of microwave and chemical disinfection on the Vickers hardness (VHN) and surface roughness (Ra, microm) of 2 hard chairside reline resins (Kooliner, DuraLiner II), and 1 heat-polymerizing denture base resin (Lucitone 550). MATERIAL AND METHODS: Specimens (12 x 12 x 3 mm) were divided into 2 control and 4 test groups (n=8). Hardness and roughness measurements were performed after: polymerization and immersion in water (37 degrees C) for 7 days (controls), or repeated exposure to disinfection by immersion in sodium perborate (50 degrees C/10 min) or microwave irradiation (650 W/6 min). Measurements of surface roughness (Ra, microm) and hardness (kg/mm(2)) were analyzed using 3-way ANOVA and Tukey's Honestly Significant Difference (HSD) test (alpha=.05). RESULTS: Microwave and chemical disinfection increased the mean (SD) hardness of Kooliner (from 4.1 to 7.5 kg/mm(2)) and DuraLiner II (from 2.6 to 5.6 kg/mm(2)), whereas Lucitone 550 (14.4 kg/mm(2)) remained unaffected. Disinfection by immersion in sodium perborate increased the surface roughness of DuraLiner II (from 0.13 to 0.26 microm) and Kooliner (from 0.16 to 0.26 microm), regardless of the number of cycles. For Lucitone 550, an increase in roughness was observed after 2 cycles of chemical disinfection (from 0.12 to 0.26 microm). Two cycles of microwave disinfection increased the roughness of both reline resins (DuraLiner II: from 0.13 to 0.22 microm; Kooliner: from 0.16 to 0.24 microm), whereas repeated microwave disinfection increased the roughness of DuraLiner II (from 0.11 to 0.25 microm). CONCLUSIONS: Disinfection by immersion in sodium perborate or microwave irradiation did not adversely affect the hardness of all materials evaluated. The effect of both disinfection methods on the roughness varied among materials.

Immediate X delayed loading dental implants: an overview

The aim of this investigation was to accomplish an overview about the principles of the indication and of the success parameters involving immediate and delayed loading dental implants procedures. Studies about the philosophies (immediate and delayed loading dental implants) and their clinical indications will be discussed in order to overview the rules for the clinical success in both techniques. In addition, studies regarding the criteria for immediate loading implants as primary stabilization, surface treatments and bone density and amount will be also analyzed. More important than the philosophy selection, is how and when to use it according to biomechanical rules and principles. Among the vast limitations pointed by the literature regarding procedures of immediate and delayed loading are evidenced the parafunctional habits, primary stabilization, bone quality, surface treatments and the number of dental implants. The anterior region of the jaw seems to be associated with a major percentage of satisfactory results, regardless of rehabilitation procedures. Although several studies have demonstrated high success rates for the immediate loading dental implants, several aspects remain without an explicit definition and further studies are needed to elucidate some reservations.

Moldagem em prótese total: uma revisão da literatura / Impression in complete dentures: a litarature review

Um grande número de trabalhos clássicos tem sido utilizado desde o início do século XIX como base para a prática de moldagem em prótese total. O presente artigo constitui-se numa revisão de literatura científica sobre os conceitos, definições, indicações e filosofias de moldagem em prótese total. Os objetivos de cada uma das filosofias descritas na literatura e a indicação de diversos materiais para moldagem são discutidos, buscando demonstrar ao clínico métodos de moldagem relativamente simples. Observou-se que os materiais de moldagem atualmente disponíveis no mercado odontológico atendem plenamente às necessidades clínicas, devendo sua escolha se basear nas características do caso a ser executado e na preferência individual de utilização dos profissionais. Mais importante do que a seleção de um determinado material de moldagem é saber como e quando empregá-lo, de acordo com a preferência e habilidade de cada profissional

Intraoral contact allergy to materials used in dental practice. A critical review.

Intraoral contact allergy reactions are clinically poorly differentiated and understood, and are not very commonly described in the specialized literature. Although such reactions appear to be scantly relevant, evidence suggests that they may be more frequent than previously believed. No single or specific clinical picture of intraoral contact allergy exists, though lichenoid reactions appear to be the most common manifestations. Epicutaneous patch testing, together with the clinical manifestations, constitute the most widely used diagnostic approach in such situations. Metals used in dental practice--particularly amalgams and gold--are the most commonly reported causes of intraoral allergic reactions, though hypersensitivity to resins is increasingly mentioned in the literature, as a consequence of their increasingly widespread use. The systematic intraoral elimination or substitution of materials inducing cutaneous hypersensitivity has recently been questioned, while on the other hand it not possible to discard an allergic component in some nonspecific stomatological disorders. The present study offers clinicians an evidence-based update of current knowledge in this field.