Paulo Renato Junqueira Zuim

Universidade de São Paulo, São Paulo, Estado de Sao Paulo, Brazil

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Publications (14)5.92 Total impact

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    Article: Effect of occlusal splint thickness on electrical masticatory muscle activity during rest and clenching.
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    ABSTRACT: The extent of separation between the maxillary and mandibular teeth in the fabrication of interocclusal splints designed to achieve efficiency and muscle relaxation is controversial and undefined in the literature. Based on this premise, the aim of this study was to evaluate the effect of interocclusal splint thicknesses of 3 and 6 millimeters on the electrical activity of the anterior temporal and masseter muscles during rest and dental clenching. Twenty asymptomatic individuals (10 males and 10 females) were selected using the Research Diagnostic Criteria (RDC). Electromyography (EMG) was performed both with and without the 3- and 6-mm splints using the Bio EMG software package, which recorded values given in microvolts (µV). The results, which were assessed using analysis of variance (ANOVA) to a 5% significance level (p < 0.05), showed increased electrical activity of the masticatory muscles during dental clenching compared with at rest, with greater activity in the masseter muscle. The electrical activity did not differ according to the thickness of the splints or between males and females. We can conclude that both splint thicknesses are effective in treating muscle hyperactivity given their similar clinical behavior for asymptomatic individuals.
    Brazilian oral research 12/2011; 25(6):506-11.
  • Article: Temporomandibular joint vibration before and after exercises and occlusal splints.
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    ABSTRACT: Temporomandibular joint (TMJ) sounds are frequent in patients. The aim of this study was to analyze patients with clicking at the end of opening and at the beginning of closing their mouths treated by muscular exercises through chewing and by occlusal splints. Fifteen patients with clinically verified clicking and TMJ and 15 patients without sounds were selected by the Research Diagnostic Criteria for Temporomandibular Disorders. They were submitted to electrovibratography at consultation and 60 and 120 days of treatment by occlusal splints and exercises. Patients demonstrated significant reduction of TMJ sounds after treatment, but vibration intensity was not similar with that of the control group after 120 days.
    The Journal of craniofacial surgery 11/2011; 22(6):e14-6. · 0.81 Impact Factor
  • Article: Evaluation of bone insertion level of support teeth in class I mandibular removable partial denture associated with an osseointegrated implant: a study using finite element analysis.
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    ABSTRACT: : This study evaluated the influence of distal extension removable partial denture associated with implant in cases of different bone level of abutment tooth, using 2D finite element analysis. : Eight hemiarch models were simulated: model A-presenting tooth 33 and distal extension removable partial denture replacing others teeth, using distal rest connection and no bone lost; model B-similar to model A but presenting distal guide plate connection; model C- similar to model A but presenting osseointegrated implant with ERA retention system associated under prosthetic base; model D-similar to model B but presenting osseointegrated implant as described in model C; models E, F, G, and H were similar to models A, B, C, and D but presenting reduced periodontal support around tooth 33. Using ANSYS 9.0 software, the models were loaded vertically with 50 N on each cusp tip. For results, von Mises Stress Maps were plotted. : Maximum stress value was encountered in model G (201.023 MPa). Stress distribution was concentrated on implant and retention system. The implant/removable partial denture association decreases stress levels on alveolar mucosa for all models. : Use of implant and ERA system decreased stress concentrations on supporting structures in all models. Use of distal guide plate decreased stress levels on abutment tooth and cortical and trabecular bone. Tooth apex of models with reduced periodontal support presented increased stress when using distal rest.
    Implant dentistry 06/2011; 20(3):192-201. · 1.51 Impact Factor
  • Article: Silent period of masticatory cycles in dentate subjects and complete denture wearers.
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    ABSTRACT: The purpose of this study was to assess, through electromyographic activity (EMG), the silent period (SP) of masseter and anterior temporal muscles in dentate subjects (DS) and complete denture wearers (CDW). The evaluations were performed at the initial and final period of the mastication for the DS group. For the CDW group, the evaluations were performed at the initial period of mastication, with old complete dentures worn for more than 10 years (OCDW) and at the final period of the mastication with new complete dentures (NCDW), 5 months after rehabilitation. Twenty-four asymptomatic subjects (12 DS, 12 CDW) answered a questionnaire based on the Research Diagnostic Criteria for temporomandibular disorders. The CDW group answered the questionnaire before and after new denture insertion and after 5 months of rehabilitation. The SP of the muscles was recorded through EMG at the initial and final periods of mastication using artificial food (Optocal). The operator monitored 35 chewing cycles performed to grind the artificial food and selected eight open-close-clench-chewing cycles for the record. The SP of the muscles analyzed with new complete dentures showed no statistical difference in comparison to the old dentures. There was a statistically significant difference in the SP between the CDW and DS groups for initial and final chewing. Lowered muscular capacity and ability reduced the SP of muscles after rehabilitation with NCDWs.
    Journal of Prosthodontics 02/2011; 20(2):130-4. · 1.01 Impact Factor
  • Article: Effect of occlusal splint treatment on the temperature of different muscles in patients with TMD.
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    ABSTRACT: The aim of this study was to evaluate the effect of occlusal splint treatment on the temperature of masseter (inferior, intermediate and superior), anterior temporal, digastric and trapezius muscles in patients with temporomandibular disorder (TMD). Thirty patients (6 male and 24 female) aged from 16 to 57 years (mean 37.8±11.4 years) were selected. The patients were diagnosed with muscular TMD by clinical examination (application of Research Diagnostic Criteria questionnaire and physical examination). Occlusal splints in acrylic resin were inserted in all patients with a weekly follow-up. The superficial thermography (°C) on the both sides of the muscles was performed using a digital thermometer in a controlled temperature room. This procedure was performed before occlusal splint insertion (patient with pain) and after the completion of the treatment (patient without pain). The data were analyzed by 2-way repeated-measures ANOVA and means were compared by Tukey HSD test (P<.05). After occlusal splint treatment a significant increase in temperature was observed in each muscle, both in the right and left sides. When the muscles were compared in the same period (before or after therapy) there was no significant difference among them. It can be concluded that the use of occlusal splint promoted a significant increase on the muscles temperature. There was symmetry in the temperature of muscles on the right and left sides both before and after the treatment.
    Journal of prosthodontic research. 01/2011; 55(1):19-23.
  • Article: Relationship between anxiety and chronic orofacial pain of temporomandibular disorder in a group of university students.
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    ABSTRACT: This study evaluated the relationship between anxiety levels and severity degrees of chronic orofacial pain of temporomandibular disorder in brazilian university students. 150 volunteers (117 men and 33 women), with age ranging from 17 to 30 years, were subjects to this study. Spielberger's trait-state anxiety inventory was used to evaluate trait and state anxiety of the students, while examination for chronic orofacial pain was performed in accordance with the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Association between anxiety levels and severity degrees of chronic orofacial pain was tested using the Chi-square test. The significance level was set at p<.05. The results showed that 32.7% (n=49) of the subjects exhibited TMD, and the intensity of chronic orofacial pain was classified as degree 1 in 85.7% (n=42) and as degree 2 in 14.3% (n=7) of them. Based on the results of the Spielberger's trait-state anxiety inventory, the majority of the students had moderate anxiety (48.6% and 48.1%, respectively). The correlation between trait-anxiety levels and chronic orofacial pain degrees was significant and positive (p<.05). However, no significant correlation was found to state-anxiety levels and chronic orofacial pain degrees (p>.05). It was concluded that chronic orofacial pain of TMD could be present in university students and anxiety may be related.
    Journal of prosthodontic research. 11/2010; 55(3):154-8.
  • Article: Silent period-dentate, edentulous, and patients with craniomandibular dysfunction.
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    ABSTRACT: The record of electrical activity of elevator muscles in mandible is important for the evaluation of muscular potency and diagnosis of neuromuscular pathologies, which allows prevention and treatment. The aim of this study was to define silent periods (SPs) and the importance in dentistry and compare the SPs in masticatory muscles of dentate and edentulous patients wearing prosthesis considering the presence or absence of craniomandibular dysfunction (CMD). Literature review in PubMed database. Silent periods are isolated pulses of transcranial magnetic stimulation in the primary motor cortex during voluntary muscular activity that generates an interruption of muscular activity for hundredths of milliseconds. The SP duration depends on the patient (dentate or edentulous), type of stimulus, and presence of CMD. The SP is higher in complete edentulous patients and in individuals with occlusal disharmonies than in dentate patients without CMDs. The treatment of CMDs through occlusal therapy decreases SP duration.
    The Journal of craniofacial surgery 09/2010; 21(5):1641-5. · 0.81 Impact Factor
  • Article: Analysis of masticatory cycle efficiency in complete denture wearers.
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    ABSTRACT: This study assessed masticatory efficiency and duration of the masticatory cycle in 14 asymptomatic patients with severe bone resorption. All patients had worn complete dentures for over 10 years. Recall visits were scheduled at 5 months and 1 year after receiving new dentures. Fourteen patients were evaluated in this study. The Research Diagnostic Criteria questionnaire and tests of the efficiency and duration of the masticatory cycle were performed with artificial food before, 5 months after, and 1 year after new dentures were delivered. Masticatory efficiency was assessed using a sieve system; artificial food was ground for 35 masticatory cycles and monitored by the operator. Masticatory efficiency at 5 months was significantly improved for the 0.42-mm mesh. An improvement in masticatory efficiency and a reduction in mastication time were observed with the new dentures after 1 year. The results of this study indicated that 5 months did not allow enough time to demonstrate improved muscular capacity and ability after receiving new dentures. After 1 year, the duration of the masticatory cycle was reduced, and masticatory efficiency was significantly improved.
    Journal of Prosthodontics 09/2009; 19(1):10-3. · 1.01 Impact Factor
  • Article: Comparative evaluation of the efficacy of occlusal splints fabricated in centric relation or maximum intercuspation in temporomandibular disorders patients.
    Marcelo Matida Hamata, Paulo Renato Junqueira Zuim, Alicio Rosalino Garcia
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    ABSTRACT: Fabrication of occlusal splints in centric relation for temporomandibular disorders (TMD) patients is arguable, since this position has been defined for asymptomatic stomatognathic system. Thus, maximum intercuspation might be employed in patients with occlusal stability, eliminating the need for interocclusal records. This study compared occlusal splints fabricated in centric relation and maximum intercuspation in muscle pain reduction of TMD patients. Twenty patients with TMD of myogenous origin and bruxism were divided into 2 groups treated with splints in maximum intercuspation (I) or centric relation (II). Clinical, electrognathographic and electromyographic examinations were performed before and 3 months after therapy. Data were analyzed by the Student's t test. Differences at 5% level of probability were considered statistically significant. There was a remarkable reduction in pain symptomatology, without statistically significant differences (p>0.05) between the groups. There was mandibular repositioning during therapy, as demonstrated by the change in occlusal contacts on the splints. Electrognathographic examination demonstrated a significant increase in maximum left lateral movement for group I and right lateral movement for group II (p<0.05). There were no significant differences (p>0.05) in the electromyographic activities at rest after utilization of both splints. In conclusion, both occlusal splints were effective for pain control and presented similar action. The results suggest that maximum intercuspation may be used for fabrication of occlusal splints in patients with occlusal stability without large discrepancies between centric relation and maximum intercuspation. Moreover, this technique is simpler and less expensive.
    Journal of applied oral science: revista FOB 02/2009; 17(1):32-8. · 0.39 Impact Factor
  • Article: Analysis of mandibular position using different methods of location.
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    ABSTRACT: There has been much discussion regarding the ideal position of the condyle in the mandibular fossa. Although the centric relation position (CR) is used as a reference, some authors do not believe that it is physiologic. Thus, the aim of this study was to evaluate in a group of asymptomatic individuals the position of the condyle in the mandibular fossa at maximum intercuspation (MI), with a occlusal splint and with a Lucia jig between the teeth. It was analyzed by means of magnetic resonance imaging (MRI), transcranial radiography imaging and analysis of horizontal axis of rotation from casts mounted on an articulator. The results showed that even if patients had mandibular displacement in positions of CR, habitual maximum intercuspation and with the occlusal splint, confirmed by means of the analysis of the horizontal axis of rotation, the images showed no statistically significant differences among condylar positions. It can therefore be concluded that the positions analyzed were similar and that transcranial radiography seems to be a reliable method for analyzing condylar position.
    Acta odontológica latinoamericana: AOL 01/2009; 22(3):155-62.
  • Article: Evaluation of temporomandibular joint noise in partially edentulous patients.
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    ABSTRACT: In order to evaluate the presence of TMD (temporomandibular disorder), dissatisfaction related to the use of removable partial dentures (RPD) and the effect of the treatment on temporomandibular joint noises, 13 female patients with Kennedy class I and II mandibular arch were selected. Another 13 young, asymptomatic, dentate patients, also female, were used as reference. After four years, 38.4% were found to have a moderate or severe degree of TMD. Over the four years, the degree of TMD increased in 46.15% of the patients, was not affected in 20.07%, while in 15.38% it decreased or the patients remained free from signs and symptoms. About 30% of the patients at the second year and 46% after the fourth year, had complaints regarding retention and stability. It was concluded that there is no relationship between TMD and the condition of partially edentulous Kennedy class I and II, but patient dissatisfaction increased after the second year and temporomandibular joint noise was reduced significantly with the replacement of the teeth.
    Acta odontológica latinoamericana: AOL 02/2008; 21(1):21-7.
  • Source
    Article: Mandible protrusion and decrease of TMJ sounds: an electrovibratographic examination.
    Alicio Rosalino Garcia, Sérgio Folli, Paulo Renato Junqueira Zuim, Valdir de Sousa
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    ABSTRACT: This study quantified by, electrovibratography, the amount of mandible protrusion required to decrease significantly temporomandibular joint (TMJ) vibratory energy as an aid in the diagnosis of the recapture of anteriorly displaced disk. Eighteen patients diagnosed as having anterior disk displacement with reduction and TMJ clicking were submitted to electrovibratographic examination at the first appointment and treated with a stabilizing appliance and anterior positioning appliance with 1 to 5 mm protrusion. Vibratory energy was checked in each of these positions. Baseline data were used as control. At the first appointment, the patients had vibrations with more elevated intensities at the middle and late phases of the mouth opening cycle. At only one clinical step, mandible protrusion was obtained with the anterior repositioning appliance, ranging from 1 to 5 mm protusion. At each new position, a new electrovibratographic exam was made. After the 5-mm mandibular projection, only 2 patients presented vibration, with means between 0.6 and 2.8 Hz. Data were analyzed statistically by ANOVA and Tukey's test (alpha=0.05). The outcomes of this study indicate that 3 mm is the minimum amount of mandible protrusion to significantly decrease the TMJ vibratory energy and to recapture the displaced articular disk.
    Brazilian dental journal 02/2008; 19(1):77-82.
  • Article: Relationship Among Temporomandibular Dysfunction and Anxiety in the Students of the Fundamental Teaching
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    ABSTRACT: Objective: With the objective of studying the temporomandibular dysfunction and anxiety levels in children, an epidemiological study was accomplished in scholars of the fundamental teaching of private schools of the Municipal District of Jaboticabal/SP. Method: For this study, 304 students were selected, being 83 of the 4th series, 117 of the 6th series and 104 of the 8th series (Committee of Ethics in Research: 200501873). The sampling was composed by children of both gender, with age among of 9 to 15 years. The evaluation was done by means of three self-applicable questionnaires: one to quantify the degree of temporomandibular dysfunction (Index of Fonseca), and two to determine the anxiety level (IDATE): Anxiety-State (“As I am feeling”) and Anxiety-Trait (“Like me I generally feel”). The Anxiety-State questionnaire indicates as the children fells in a certain moment. The Anxiety-Trait questionnaire determines how the children generally fells during its lives. Results: The obtained data were tabulated and it allowed to arrive the following average scores of Index of Fonseca, Anxiety-State and Anxiety-Trait: 25.61 (13.25); 31.35 (5.03) and 38.61 (5.29), respectively. Conclusion: It was concluded that a great part of children’s of fundamental teaching showed signs and symptoms of TMD and presented themselves quite anxious. Besides, analysis of data showed that a positive correlation exists between temporomandibular dysfunction and anxiety (p<0.01), mainly when comparing Trace anxiety, which is strongly related with personality.
    Pesquisa Brasileira em Odontopediatria e Clínica Integrada. 01/2007;
  • Article: Evaluation of microcurrent electrical nerve stimulation (MENS) effectiveness on muscle pain in temporomandibular disorders patients.
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    ABSTRACT: The effect of Microcurrent Electrical Nerve Stimulation (MENS) was evaluated and compared with occlusal splint therapy in temporomandibular disorders (TMD) patients with muscle pain. Twenty TMD patients were divided into four groups. One received occlusal splint therapy and MENS (I); other received splints and placebo MENS (II); the third, only MENS (III) and the last group, placebo MENS (IV). Sensitivity derived from muscle palpation was evaluated using a visual analogue scale. Results were submitted to analysis of variance (p<0.05). There was reduction of pain level in all groups: group I (occlusal splint and MENS) had a 47.7% reduction rate; group II (occlusal splint and placebo MENS), 66.7%; group III (MENS), 49.7% and group IV (placebo MENS), 16.5%. In spite of that, there was no statistical difference (analysis of variance / p<0.05) between MENS and occlusal splint therapy regarding muscle pain reduction in TMD patients after four weeks.
    Journal of applied oral science: revista FOB 01/2006; 14(1):61-6. · 0.39 Impact Factor