Contrôle cortico-spinal des mouvements volontaires du coude

Il existe plusieurs théories du contrôle moteur, chacune présumant qu’une différente variable du mouvement est réglée par le cortex moteur. On trouve parmi elles la théorie du modèle interne qui a émis l’hypothèse que le cortex moteur programme la trajectoire du mouvement et l’activité électromyographique (EMG) d’une action motrice. Une autre, appelée l’hypothèse du point d’équilibre, suggère que le cortex moteur établisse et rétablisse des seuils spatiaux; les positions des segments du corps auxquelles les muscles et les réflexes commencent à s’activer. Selon ce dernier, les paramètres du mouvement sont dérivés sans pré-programmation, en fonction de la différence entre la position actuelle et la position seuil des segments du corps. Pour examiner de plus près ces deux théories, nous avons examiné l’effet d’un changement volontaire de l’angle du coude sur les influences cortico-spinales chez des sujets sains en employant la stimulation magnétique transcrânienne (TMS) par-dessus le site du cortex moteur projetant aux motoneurones des muscles du coude. L’état de cette aire du cerveau a été évalué à un angle de flexion du coude activement établi par les sujets, ainsi qu’à un angle d’extension, représentant un déplacement dans le plan horizontal de 100°. L’EMG de deux fléchisseurs du coude (le biceps et le muscle brachio-radial) et de deux extenseurs (les chefs médial et latéral du triceps) a été enregistrée. L’état d’excitabilité des motoneurones peut influer sur les amplitudes des potentiels évoqués moteurs (MEPs) élicitées par la TMS. Deux techniques ont été entreprises dans le but de réduire l’effet de cette variable. La première était une perturbation mécanique qui raccourcissait les muscles à l'étude, produisant ainsi une période de silence EMG. La TMS a été envoyée avec un retard après la perturbation qui entraînait la production du MEP pendant la période de silence. La deuxième technique avait également le but d’équilibrer l’EMG des muscles aux deux angles du coude. Des forces assistantes ont été appliquées au bras par un moteur externe afin de compenser les forces produites par les muscles lorsqu’ils étaient actifs comme agonistes d’un mouvement. Les résultats des deux séries étaient analogues. Un muscle était facilité quand il prenait le rôle d’agoniste d’un mouvement, de manière à ce que les MEPs observés dans le biceps fussent de plus grandes amplitudes quand le coude était à la position de flexion, et ceux obtenus des deux extenseurs étaient plus grands à l’angle d’extension. Les MEPs examinés dans le muscle brachio-radial n'étaient pas significativement différents aux deux emplacements de l’articulation. Ces résultats démontrent que les influences cortico-spinales et l’activité EMG peuvent être dissociées, ce qui permet de conclure que la voie cortico-spinale ne programme pas l’EMG à être générée par les muscles. Ils suggèrent aussi que le système cortico-spinal établit les seuils spatiaux d’activation des muscles lorsqu’un segment se déplace d’une position à une autre. Cette idée suggère que des déficiences dans le contrôle des seuils spatiaux soient à la base de certains troubles moteurs d’origines neurologiques tels que l’hypotonie et la spasticité.

Les appareils myofonctionnels de correction de la Classe II : l’EMG.

Introduction: La correction de la Classe II avec un appareil myofonctionnel est un traitement commun chez les patients en croissance. Le Twin Block et le correcteur de Classe II fixe (CCF) sont des appareils populaires et plusieurs publications scientifiques ont décrit leurs effets sur les tissus orofaciaux. Plusieurs articles rapportent les changements de l’électromyographie des muscles de la mastication durant le traitement avec un Twin Block, mais peu d’articles ont étudié ces changements avec un CCF. Comme le Twin Block et le CCF ont des biomécaniques différentes, leur influence sur les muscles est possiblement différente. Objectifs: Évaluer les adaptations musculaires suite à un traitement par appareil myofonctionnel : Twin Block et CCF. Matériels et méthodes: Dans une étude cohorte prospective, 24 patients en pic de croissance ont été assignés aléatoirement à un traitement (13 Twin Block; 11 CCF) et l’EMG des muscles masséters et temporaux a été mesurée à 1, 5, 13, 21, 29, 37 semaines. Les muscles ont été mesurés sous trois états: au repos, en occlusion centré (OC) et en contraction volontaire maximal (CVM) Résultats: Les données ont été analysées à l’aide d’un modèle mixte linéaire à mesures répétées et ont été documentées pour chaque muscle selon quatre conditions: i- avec Twin Block en bouche, ii- sans Twin Block en bouche iii- avec CCF en bouche et iv- sans Twin Block comparé au groupe avec CCF. Dans la condition i, des résultats significatifs ont été observés au repos pour le masséter droit et gauche, ainsi que le temporal gauche avec une valeur-p≤0.005. En CVM, la condition i montre aussi des résultats significatifs pour le masséter droit et le temporal gauche avec une valeur-p≤0.05. Les conditions ii et iii ont obtenu des résultats non-significatifs en tout temps. Par contre, lorsque ces deux conditions sont comparées l’une à l’autre (condition iv), des résultats significatifs ont été obtenus en OC pour les temporaux gauche et droit avec une valeur-p=0.005. Conclusions: Avec le Twin Block en bouche, l’EMG augmente au cours du temps en CVM, mais diminue en OC. Par contre, sans le Twin Block en bouche et avec le CCF en bouche, l’EMG ne varie pas. Cependant, le Twin Block et le CCF sont différents au niveau des mesures de l’EMG au cours des neuf mois de traitement. Ceci peut être expliqué par le nivellement graduel de l’occlusion postérieure durant le traitement avec le CCF qui ne se produit pas avec le Twin Block.

Hypoxie transitoire en relation avec les activités rythmiques des muscles de la mastication chez les patients atteints du bruxisme du sommeil

Study Objectives: Sleep bruxism (SB) is a repetitive jaw-muscle activity characterized by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible occurring during sleep. SB is scored, from electromyographic traces, as rhythmic masticatory muscle activity (RMMA). Most RMMA occurred during sleep in association with sleep arousal. Since not all RMMA episodes were associated with sleep arousal we hypothesized that some event could be observed in relation to small fluctuations of the oxygen level resulting in mild desaturation/hypoxia. Methods: Sleep laboratory or home recordings from 22 SB (teeth grinding) patients were analyzed from our data bank. A total of 143 RMMA/SB episodes were classified in 4 categories: (i) no arousal & no body movement; (ii) arousal + & no body movement; (iii) no arousal & body movement +; (iv) arousal + & body movement +. Minimum blood oxygen levels were assessed from finger oxymetry signal: 1) during the baseline period before RMMA, i.e., an average of 7 s before RMMA onset (-20 s to -14 s); 2) during RMMA, i.e. a window of 15 s corresponding to -5 s before the onset until +10 s after the episode. For all episodes, the minimum oximetry values were compared for each patient. Results: There was a significant variation of blood oxygen level over time (p=0.001) with a statistically significant transient hypoxia during RMMA at time (+7),(+8) and (+9) s. The variation over time was similar among the 4 groups (non significant group*time interaction p=0.10) and no overall difference was observed between groups (p=0.91). Of the 22 subjects, 6 subjects (27%) remained equal or had a slight increase in SaO2 (+8) s after the RMMA/SB onset compared to baseline (-20 s to -14) s, 10 subjects (45%) showed a small decrease in SaO2 (>0 to <1%) and 6 others (27%) had a decrease of 1-1.8%. Conclusions: These preliminary findings suggest that in some SB patients, RMMA episodes are potentially triggered by minor transient hypoxia. Key words: sleep bruxism, oximetry, desaturation, hypoxia, rhythmic masticatory muscle activity

Development and plasticity of locomotor circuits in the zebrafish spinal cord

A fundamental goal in neurobiology is to understand the development and organization of neural circuits that drive behavior. In the embryonic spinal cord, the first motor activity is a slow coiling of the trunk that is sensory-independent and therefore appears to be centrally driven. Embryos later become responsive to sensory stimuli and eventually locomote, behaviors that are shaped by the integration of central patterns and sensory feedback. In this thesis I used a simple vertebrate model, the zebrafish, to investigate in three manners how developing spinal networks control these earliest locomotor behaviors. For the first part of this thesis, I characterized the rapid transition of the spinal cord from a purely electrical circuit to a hybrid network that relies on both chemical and electrical synapses. Using genetics, lesions and pharmacology we identified a transient embryonic behavior preceding swimming, termed double coiling. I used electrophysiology to reveal that spinal motoneurons had glutamate-dependent activity patterns that correlated with double coiling as did a population of descending ipsilateral glutamatergic interneurons that also innervated motoneurons at this time. This work (Knogler et al., Journal of Neuroscience, 2014) suggests that double coiling is a discrete step in the transition of the motor network from an electrically coupled circuit that can only produce simple coils to a spinal network driven by descending chemical neurotransmission that can generate more complex behaviors. In the second part of my thesis, I studied how spinal networks filter sensory information during self-generated movement. In the zebrafish embryo, mechanosensitive sensory neurons fire in response to light touch and excite downstream commissural glutamatergic interneurons to produce a flexion response, but spontaneous coiling does not trigger this reflex. I performed electrophysiological recordings to show that these interneurons received glycinergic inputs during spontaneous fictive coiling that prevented them from firing action potentials. Glycinergic inhibition specifically of these interneurons and not other spinal neurons was due to the expression of a unique glycine receptor subtype that enhanced the inhibitory current. This work (Knogler & Drapeau, Frontiers in Neural Circuits, 2014) suggests that glycinergic signaling onto sensory interneurons acts as a corollary discharge signal for reflex inhibition during movement. v In the final part of my thesis I describe work begun during my masters and completed during my doctoral degree studying how homeostatic plasticity is expressed in vivo at central synapses following chronic changes in network activity. I performed whole-cell recordings from spinal motoneurons to show that excitatory synaptic strength scaled up in response to decreased network activity, in accordance with previous in vitro studies. At the network level, I showed that homeostatic plasticity mechanisms were not necessary to maintain the timing of spinal circuits driving behavior, which appeared to be hardwired in the developing zebrafish. This study (Knogler et al., Journal of Neuroscience, 2010) provided for the first time important in vivo results showing that synaptic patterning is less plastic than synaptic strength during development in the intact animal. In conclusion, the findings presented in this thesis contribute widely to our understanding of the neural circuits underlying simple motor behaviors in the vertebrate spinal cord.

Effets du port continu de coquilles correctrices Invisalign® sur l’articulation temporo-mandibulaire et les muscles du complexe facial.

INTRODUCTION : L’articulation temporo-mandibulaire (ATM) est un système articulaire excessivement complexe. L'étiologie des désordres temporo-mandibulaires (DTM) est encore incertaine et le lien de cause à effet des traitements orthodontiques en tant que facteur de risque est une question qui a longuement été discutée. Cette étude clinique prospective vise à évaluer les effets à long terme du port continu de coquilles correctrices Invisalign® sur l’ATM et les muscles du complexe facial. MATÉRIELS ET MÉTHODES : L'étude incluait 43 adolescents et adultes âgés entre 13 et 51 ans (25 femmes et 18 hommes). Deux d'entre eux ont été exclus en raison de mauvaise coopération causant l’arrêt du traitement orthodontique. Les effets dans le temps des coquilles sur l'ATM et les muscles du complexe facial ont été évalués en utilisant l’examen du Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Le nombre de contractions musculaires durant le sommeil a été mesuré objectivement par enregistrements électromyographiques (EMG) et la fréquence de grincement et de serrement des dents à l’éveil a été rapportée subjectivement par les patients à l’aide de questionnaires. Des mesures répétées ont été effectuées aux temps suivants: avant le début du traitement pour les données contrôles (T1), deux semaines (T2), et six mois (T3) après le début du traitement. Les données numériques ont été analysées par l’analyse de variance (ANOVA) en mesures répétées et la méthode de Brunner-Langer, alors que les données nominales ont été évaluées par le test de Cochran-Mantel-Haenszel. Les résultats ont été considérés significatifs si p < 0.05. RÉSULTATS ET DISCUSSION : Le nombre de contractions musculaires par heure (index) durant le sommeil et leur durée moyenne n’ont pas été statistiquement différents entre les trois nuits d’enregistrement EMG (Brunner Langer, p > 0.005). Cependant, 67 % des participants ont rapporté avoir eu du grincement ou du serrement des dents la nuit au T2 et 64 % au T3 comparativement à 39 % au T1, ce qui était une augmentation significative (Cochran-Mantel-Haenszel, p = 0.0112). Quarante-quatre pour cent des patients ont signalé du grincement ou du serrement des dents pendant le jour au T1, tandis qu'un pourcentage nettement plus élevé de 66 % en a rapporté au T2 et 61 % au T3 (Cochran-Mantel-Haenszel, p = 0.0294). Au T1, 12 % des sujets ont indiqué qu'ils se sont réveillés avec une douleur musculaire, comparativement à 29 % au T2, ce qui était une augmentation significative (Cochran-Mantel-Haenszel, p = 0.0347). Au T2, il y avait une réduction significative des mouvements maximaux de la mandibule dans toutes les directions (ANOVA en mesures répétées, p < 0,05). De plus, il y a eu une augmentation significative du nombre de sites douloureux et de l'intensité de la douleur à la palpation de l'ATM et des muscles faciaux avec l'évaluation du RDC/TMD au T2 en comparaison aux T1 et T3 (Brunner Langer, p < 0,05). CONCLUSION : La présente étude n’a révélé aucun effet des coquilles sur l’activité oro-faciale durant le sommeil au fil du temps mesurée objectivement à l’aide des enregistrements EMG, mais une augmentation significative de la fréquence du grincement et du serrement des dents rapportée subjectivement par les patients au moyen des questionnaires aux T2 et T3. Au T2, il y avait une augmentation significative des symptômes de l'ATM et des muscles du complexe oro-facial, mais ces symptômes sont retournés au niveau initial avec le temps.

Lymph heart in chick - somitic origin, development and embryonic oedema

The lymph heart is a sac-like structure on either side of avian tail. In some adult birds, it empties the lymph from the copulatory organ; however, during embryonic development, it is thought to circulate extra-embryonic lymph. Very little is known about the origin, innervation and the cellular changes it undergoes during development. Using immunohistochemistry and gene expression profiling we show that the musculature of the lymph heart is initially composed solely of striated skeletal muscle but later develops an additional layer composed of smooth myofibroblasts. Chick-quail fate-mapping demonstrates that the lymph heart originates from the hypaxial compartments of somites 34-41. The embryonic lymph heart is transiently innervated by somatic motoneurons with no autonomic input. In comparison to body muscles, the lymph heart has different sensitivity to neuromuscular junction blockers (sensitive only to decamethonium). Furthermore, its abundant bungarotoxin-positive acetylcholinesterase receptors are unique as they completely lack specific acetylcholinesterase activity. Several lines of evidence suggest that the lymph heart may possess an intrinsic pacing mechanism. Finally, we assessed the function of the lymph heart during embryogenesis and demonstrate that it is responsible for preventing embryonic oedema in birds, a role previously thought to be played by body skeletal muscle contractions.

Computer generation and quantitative morphometric analysis of virtual neurons

An important goal in computational neuroanatomy is the complete and accurate simulation of neuronal morphology. We are developing computational tools to model three-dimensional dendritic structures based on sets of stochastic rules. This paper reports an extensive, quantitative anatomical characterization of simulated motoneurons and Purkinje cells. We used several local and global algorithms implemented in the L-Neuron and ArborVitae programs to generate sets of virtual neurons. Parameters statistics for all algorithms were measured from experimental data, thus providing a compact and consistent description of these morphological classes. We compared the emergent anatomical features of each group of virtual neurons with those of the experimental database in order to gain insights on the plausibility of the model assumptions, potential improvements to the algorithms, and non-trivial relations among morphological parameters. Algorithms mainly based on local constraints (e.g., branch diameter) were successful in reproducing many morphological properties of both motoneurons and Purkinje cells (e.g. total length, asymmetry, number of bifurcations). The addition of global constraints (e.g., trophic factors) improved the angle-dependent emergent characteristics (average Euclidean distance from the soma to the dendritic terminations, dendritic spread). Virtual neurons systematically displayed greater anatomical variability than real cells, suggesting the need for additional constraints in the models. For several emergent anatomical properties, a specific algorithm reproduced the experimental statistics better than the others did. However, relative performances were often reversed for different anatomical properties and/or morphological classes. Thus, combining the strengths of alternative generative models could lead to comprehensive algorithms for the complete and accurate simulation of dendritic morphology.

Exploratory factor analysis of the Brazilian OHIP for edentulous subjects

P>The use of seven domains for the Oral Health Impact Profile (OHIP)-EDENT was not supported for its Brazilian version, making data interpretation in clinical settings difficult. Thus, the aim of this study was to assess patients` responses for the translated OHIP-EDENT in a group of edentulous subjects and to develop factor scales for application in future studies. Data from 103 conventional and implant-retained complete denture wearers (36 men, mean age of 69 center dot 1 +/- 10 center dot 3 years) were assessed using the Brazilian version of the OHIP-EDENT. Oral health-related quality of life domains were identified by factor analysis using principal component analysis as the extraction method, followed by varimax rotation. Factor analysis identified four factors that accounted for 63% of the 19 items total variance, named masticatory discomfort and disability (four items), psychological discomfort and disability (five items), social disability (five items) and oral pain and discomfort (five items). Four factors/domains of the Brazilian OHIP-EDENT version represent patient-important aspects of oral health-related quality of life.

Mastication effort study using photorefractive holographic interferometry technique

The purpose of this work was the force-displacement response analysis of the masticatory process in a dried human skull by Double-Exposure Photorefractive Holographic Interferometry Technique (2E-PRHI). The load concentration and dissipation of the forces from dried human skull were analysed at applied loading stands as a Simulation of Isolated Contraction (SIC) of some mastication muscles. The 2EHI and Fringe Analysis Method were used to obtain the quantitative results of this force-displacement response. These results document quantitatively the real biomechanical response from dried human skull under applied loading and it can be used for complementary study by finite element model and others analysis type. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.

CONTROL of THE CENTRAL CHEMOREFLEX BY A5 NORADRENERGIC NEURONS IN RATS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação clínica e comparativa da oclusão balanceada bilateral e desoclusão com guia canino sobre a função mastigatória de usuários de prótese total removível

The maintenance of masticatory function is especially important for patients who wear complete dentures due to the limitations of this type of prosthesis. Thus, the bilateral balanced occlusion (BBO) is used to achieve, besides other advantages, greater masticatory efficiency. However, analyzing critically the literature, it is observed that there is not enough scientific evidence that support the BBO as the most appropriate occlusal concept in complete dentures. This way, the purpose of the present study was to verify if complete dentures wearers with BBO present better masticatory efficiency and capacity than those with canine guidance (CG). A double-blind controlled crossover clinical trial was conducted. The sample was made of 24 completely edentulous patients. The subjects wore sets of complete dentures with both occlusal concepts for equal periods of 3 months. Objective data were collected through the masticatory efficiency test, performed by the colorimetric method, 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, which is the masticatory ability. No significant statistical difference was found for masticatory efficiency (p=0,0952) and masticatory ability (x2=0,5711/ p=0,4498) between the two occlusal concepts studied, as well as there was no correlation between these two variables (p=0,2985). Based on these results, it seems reasonable to use CG for the setup of complete dentures, since it is an easier and quicker technical procedure, until that future researches can come to complement this question

Qualidade de vida, eficiência mastigatória e presença de disfunção temporomandibular em usuários de prótese parcial removível com arco dental curto inferior

Even nowadays there is in Brasil a large number of edentulous and a precarious financial condition of most of the population. In addition, World Health Organization aims for oral health, which consists on the maintenance of a natural dentition, functional and aesthetic composed of at least 20 teeth, without need of prosthetic intervention throughout life. From this and considering the lack of researches about the permanence of edentulous spaces in the oral cavity, and also avoiding overtreatment, this research has been proposed. Thus, the aim was to evaluate the effect of different lengths of the shortened lower dental arch in the presence or absence of a removable partial denture (RPD) on masticatory function, quality of life and occurrence of temporomandibular dysfunction. To achieve this goal, we compared the masticatory efficiency (colorimetric test), the oral comfort through the analysis of the impact of oral health in quality of life (OHIP-14), the presence of temporomandibular dysfunction (RDC/TMD) and the general quality of life (WHOQOL) of patients with shortened dental arches (SDA) (n=60), which is an arch with a reduction of teeth starting posteriorly, and patients with complete dental arch (Complete DA) (n = 34). The group of patients whit SDA was divided among PPR wears (PPD + SDA) (n = 17) and non-wears (n = 43). The population of this study consisted on patients who received or looked for treatment at the clinics of the Department of Dentistry of UFRN, from clinical analysis and records. The sample was chosen by convenience. For statistical analysis, it was a database in SPSS 17.0, followed by descriptive analysis with frequencies, absolute values, tests of central tendency and variability. The statistical tests used were chi-squared and analysis of variance as well as Tukey s post test, when applicable, all with a 95% confidence level. The results shown a prevalence of TMD of 47,1% among patients using PRP and 69,8% among those who didn t, but this result wasn t statistically significant. The mean of the results of masticatory efficiency, WHOQOL and OHIP didn t show association to the presence or absence of PPR and to the lower number of occlusal units of the patients (0, 1, 2 or more occlusal). The association only occurred among the different groups of SDA and the patients with complete dental arch. Taking into account the results, it could be observed that studied patients with low posterior support using lower PRP didn t have better masticatory efficiency, general quality of life, less impacts of their oral conditions in quality of life or not even less temporomandibular dysfunction or better masticatory efficiency when compared to those who didn t use the prosthesis

Eficiência mastigatória e impacto da saúde oral na qualidade de vida em pacientes reabilitados com próteses totais removíveis implanto-suportadas

Edentulous patients with complaint about mandibular conventional denture might experience poor masticatory function and negative impact of oral health on quality of life. The aim of this controlled clinical trial was to evaluate the effect of mandibular overdenture on oral health-related quality of life and masticatory efficacy in patients wearing mandibular complete dentures. The edentulous patients (n=16) were rehabilitated with new maxillary and mandibular complete dentures and, after 3 months, mandibular overdentures retained by 2 implants (bar-clip system) were fabricated. The Brazilian version of OHIP-Edent questionnaire was used to assess the oral healthrelated quality of life. Masticatory efficacy was evaluated through a colorimetric method with chewing capsules. The mean OHIP-Edent score was 8.5 with conventional dentures and 2.0 with mandibular overdenture, which means a positive impact of oral health on quality of life with overdentures (p=0.001). The mean absorbance for masticatory efficacy was 0.025 for conventional dentures and 0.073 for overdentures. There was statistically significant difference for masticatory efficacy before and after implants rehabilitation (p=0.003). However, there was no correlation between masticatory efficacy and OHIP (p>0.05). So, mandibular overdenture retained by 2 implants improved the quality of life and masticatory efficacy of edentulous patients with complaint about mandibular conventional complete dentures

Recovering the function and esthetics of fractured teeth using several restorative cosmetic approaches. Three clinical cases

The teeth most commonly affected by trauma are the maxillary central incisors. The most frequent types of traumatic dental injuries to permanent teeth are enamel fractures, enamel and dentine fractures, and enamel and dentine fractures with pulp involvement. This article describes three clinical cases with different levels of traumatized maxillary incisors and several cosmetic approaches for recovery of the esthetics and the masticatory function, as well as the social/psychological aspects of treatment. All cases involved young adult men. The three clinical cases involve dentin and enamel fractures, dentin and enamel fractures with pulp exposure, and dentin and enamel fractures with pulp exposure associated with root fracture. The cosmetic treatments used to resolve fractures were direct composite resin by layering technique, indirect all-ceramic restorations (laminate veneer and ceramic crowns over the teeth), and immediate implant after extraction followed by immediate loading (ceramic abutments with ceramic crown over implant). In all three cases, excellent functional and esthetic results were achieved by use of these treatment modalities. The patients were very satisfied with the results.

Peripheral Ossifying Fibroma

The peripheral ossifying fibroma (POF) is a common gingival growth usually arising from the interdental papilla. The anterior maxilla is the most common location of involvement. The etiology and pathogenesis of POF remains unknown. Some investigators consider it a neoplastic process, whereas others argue that it is a reactive process; in either case, the lesion is thought to arise from cells in the periodontal ligament. Trauma or local irritants, such as dental plaque, calculus, microorganisms, masticatory force, ill-fitting dentures, and poor quality restorations, have been implicated in the etiology of POF. The recommended treatment is the excisional biopsy; however, it can leave a defect if the procedure is not followed by a subepithelial connective tissue graft. The main objective of this article was to present a clinical case of excisional biopsy of a POF followed by a subepithelial connective tissue graft to correct the defect caused by the biopsy. The biopsy defect was satisfactorily repaired, and the lesion has not recurred after 6 years of follow-up.