Repositório RCAAP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

The refinement of the coronary portion of the intraradicular post cemented constitutes in routine in the clinic. However, the effects of the action of the diamond burn in high rotation on the cement agent are little argued. This study is tested the hypothesis of that the refinement with high rotation an the passed time between the cementation and the accomplishment of the refinement have negative effect in the tensile strength of the intraradicular post cemented in bovine roots. Forty eight bovine roots have been parted with 15mm of length, endodontically treated, confectioned in Cu-Al league, cemented with cement zinc phosphate and divided in 4 experimental groups (n=12). Group A: Without refinement; Group B, C e D submitted the refinement 15, 60 minutes and 24 hours respectively, after the cementation. The assay was carried through in universal machine (EMIC) with speed of 0,5mm/min for all the groups 24 hours after the cementation. The data of tensile strength had been analyzed by the analysis of the variance and test of Bartlet (α=1%). Verified that it did not have significant difference between the groups. Inside of the limitation of this study it can be concluded that the refinement with high rotation and the factor passed time between the cementation and assay did not produce effect of the resistance of the intraradicular posts.

The aim of this study was to evaluate, by means of microbiological in vitro analyses, the capacity and the inhibition period of bacterial growth of the resorbable membranes of bovine bone doxycycline loaded and to compare them with the tetracycline hydrochloride loaded ones. Three variations of the resorbable membrane of bovine bone from the Biochemist laboratory of USPBauru were tested: conventional (C), tetracycline loaded (T) and doxycycline loaded (D). Microbiological analyses based in tests of in vitro sensibility to antimicrobials were made. Aerobic bacteria (Escherichia coli and Staphylococcus aureus) and a pool of nonaerobic bacteria were sown in plates with appropriate media cultures proceeding from the material collected into periodontal pockets. Each plate was divided in four regions and 3 standardized samples of the membranes were deposited, keeping an area without sample to confirm the bacterial growth. It was used a conventional membrane (C) to verify if it presented antimicrobial properties and in the other two regions it was placed (D) and (T) samples. Three plates (1, 2 and 3) were made for each bacterial group, being the doxycycline and tetracycline hydrochloride fragments called (C1/D1/T1; C2/D2/T2; C3/D3/T3) respectively. The aerobic plates were kept into a greenhouse at 35 °C and the nonaerobic ones were kept into a specific anaerobic storage jar. Weekly analyses exchanging the fragments for new plates were made and the capacity of the membranes in inhibiting the evaluated bacterial growth from the formation of inhibition halos around of each sample, which had its diameters surveyed with a digital caliper. The halos presence and the integrity of the samples determined the time of the experiment. The results showed that in all plates of the three bacterial groups, where the samples of (C) were present, did not occur an inhibition of the bacterial growth, thus presenting no halo. In the areas where the membrane was placed (D), as for the E.coli and S.aureus culture, it was observed inhibition halos up to 35 days. It was observed inhibition halos in the membrane (T) areas up to 28 days, except for E.coli (14 days). For both membranes (D) and (T), the maximum inhibition period for the anaerobic pool was 21 days, except for sample (D) present in plate 2, where the halo was present at the 28th day.

The objective of this work was to evaluate the microtensile bond strength to the human enamel of three different adhesive systems. Twenty one not prepared third molar human teeth (n=21) had been divided in three groups, with seven teeth in each group (n=7), as the used adhesive system: SB - Adper Single Bond 2 (3M/ESPE, St Paul, MN, the USA); CL - Clearfil IF Bond (Dental Kuraray, Osaka, Japan); XE - XENO III (Dentsply, Detrey, Konstanz, Germany). The teeth used were unbroken and none of them were prepared. After the adhesive protocols, a composed resin nanoparticule (Filtek Z 350, 3M/ESPE, St. Paul, MN,USA) were placed in 4 (four) layers of 1,0mm, separately and lightcured per 40 seconds. For the microtensile bond test the samples had been cut parallel to the long axle of teeth, with constant irrigation until getting beams of 1 (one) mm2 of area. For the microtensile bond strength test the samples were tested in a Universal Testing Machine (EMIC DL 2000, São José dos Pinhais, Paraná, Brasil) with a cross head speed of 0,5 speed of mm/min. Observing the normality of distribution of the data, the analysis of variance and the Test of Tukey (p<0,05) indicated differences between the groups. The average values (MPa) for each group had been: SB: 16,12 ± 7.64a; CB: 11,30 ± 5,47ab e, XE: 8,65 ± 6,19b. The results had indicated that the step of acid conditioning of the human enamel resulted in force of significantly bigger union of the Adper Single Bond 2 (3M/ESPE, St Paul, MN, the USA) in relation to XENO III (Dentsply, Detrey, Konstanz, Germany), that is of only step.

The aim of this study was to assess the occurrence of syphilis and its oral manifestations in patients attended in a teaching hospital of a medical school in Uberlândia, Brazil, between 1999 and 2006, in view of its recent resurgence related in Europe, Unites States and Latin America and the current worry about spreading during the practice of dentistry. At the period of this study, 1,229,964 patients were attended at the teaching hospital witch 298 has confirmed diagnosis of syphilis in all clinical forms, by clinical and laboratorial findings. We have collected epidemiological data including gender, age, race, origin, stage of occurrence and oral manifestations. Data was subjected to descriptive and statistical evaluation. Results demonstrate that of the 289 syphilis cases, 99 was congenital syphilis and 199 acquired syphilis. Of these 199 cases, 101 were male and the mean age was 36,5 years (range, 16-81 years). The majority of cases were white (57%). Acquired syphilis showed 5 cases as primary syphilis (2,5%), 33 cases as secondary(16,5%), 49 cases as latent (25%), 8 cases as tertiary (4%) and 87 cases as treated(44%). Among these cases, 5% presented with oral manifestations and 13,5% of cases were HIV positive. The occurrence of syphilis, in the studied population was only 0,024% and variation was statistically significant between 2004 and 2005, in which a decrease was noted. The percentual of oral manifestations when cases of latent and treated syphilis (asymptomatic disease) was excluded, achieved 15,8%. The high prevalence of congenital syphilis can reflect the diagnosis efforts, since the implantation of congenital syphilis eradication program by the Brazilian Health Department. Considering the rarity of nonsexual transmission of syphilis and the low percentual of cases in our sample, we believe that contagion and dissemination risk during the practice of dentistry is low in studied population.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Nitric oxide has an important effect on host response. However its potential as a possible diagnostic tool in peri-implant disease has been little studied. In this study the nitrite levels in saliva and peri-implant sulcular fluid (PISF) of partially edentulous patients and the possible correlation between these levels and clinical parameters were determined. Twenty four patients were examined to determine the peri-implant status (healthy or diseased) based on probing depth (PD), bleeding on probing (BOP) and presence of visible plaque (VP). Saliva and sulcular fluid (SF) around teeth (internal control) and dental implants were collected and the nitrite levels were evaluated by the Griess method. Nitrite levels in saliva and SF of these patients were compared and their correlations with clinical parameters were evaluated. Clinical data (BOP and VP) were higher in implants than in matching control teeth, but did not show significance (p>0.05) with the exception of PD. Differences in total nitrite levels in saliva and SF of healthy and diseased groups were not observed (p>0.05). Teeth and implants of healthy or diseased groups did not demonstrate statistical difference regarding nitrite levels (p>0.05). Correlation between clinical parameters and nitrite levels in saliva or SF was not observed in healthy or diseased groups except for VP in implants of the healthy group (p=0.031, r=- 0.72). These results demonstrated similarity between dental sites and implants. The present findings do not allow the use of nitrite as a diagnostic tool for periimplant disease, in patients with slight inflammation.

The aim of this study was to evaluate the efficiency of two calcium hydroxide removal techniques as intracanal medication. Ninety mandibular central incisors were transversally sectioned, in order to provide an 18mm standardization of the root in length. The canals were biomechanically prepared, then the roots were divided into 2 groups (n = 45): Group A manual technique of medication removal; and group B manual technique and ultrasound application. The intracanal medication used in each group was calcium hydroxide associated to different vehicles (n = 10), as follows: G1 saline solution; G2 PA; G3 Polyethyleneglycol; G4 Polyethyleneglycol + PMCC and G5 no medication (n = 5, control).The teeth were stored in a 100% moisture condition. After 7 days, the medication was removed and the roots were longitudinally sectioned. The inner portion of the canal was evaluated by means of digitalized photographic images, and the remaining portions were macroscopically quantized using the Imagetool software, taking into account the cervical, medium and apical thirds. According to the Kruskal-Wallis test, there were found statistically significant differences among Group A thirds, in the subgroup that used calcium hydroxide and saline. There were no statistically significant differences found in Group B thirds, regardless the subgroup assessed. When the root canal was considered as a whole, the Kruskal-Wallis test was applied, and only Group B presented statistically significant differences, among the 4 subgroups values, demonstrating that this removal was more efficient to the calcium hydroxide + saline solution. The Mann- Whitney U test compared groups A and B, verifying that only the calcium hydroxide + saline solution subgroups presented statistically significant differences, concluding that the manual technique enforced by an ultra-sound device had left less remaining residuals quantities of this association into the canals.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

The objective of this study was to evaluate the resistance the microabrasion of composed resins, amalgam, human and bovine dental enamel. A microabrasion apparel was used (Calowear Tester) whose main characteristic is to evaluate the wear of the surface of the materials. Being the abrasive wear a process of multiple risks, the resistance to the wear can be intimately related to the resistance to the risk. Like this, of ownership of the resistances the microabrasion was possible compare them the resistances to the wear of the standard minerals of the scale of hardness Mohs. Seven universal resins were used (Charisma, Esthet X, Filtek Supreme, Filtek Z250, Herculite XRV, Tetric Ceram and Z100), two universal resins compacted (Filtek P60 and Surefil) and two laboratory resins (ArtGlass and Cristobal); an amalgam with high copper tenor (GS80); third ten human molars and ten incisive bovine. After the preparation of the samples, they were submitted to the microabrasion test with application of load of 0,16 N tends aqueous dispersion of alumina as abrasive for 1 minute. This process generated impressions that were measured being used an image analyzer. Of ownership of these measured the Analysis of Variance was applied for p <0,05 and test of Tukey. The results showed different resistance levels the microabrasion for the rehearsed materials what allowed classify them orderly in agreement with his/her resistance the microabrasion. The human enamel obtained the smallest wear. Among the restoring materials the amalgam and Filtek Supreme presented larger resistance to the wear. In relation to hardness Mohs the dental enamels and the amalgam presented hardness Mohs 5 (Apatite) while the resins composed hardness Mohs 4 (Fluorite). The results showed that the evaluation of the resistance the microabrasion of the materials compared the resistance to the wear of the standard minerals of the scale of hardness Mohs, it can contribute to an effective classification of those materials being used of measured no subjective.

The aim of this study was to observe the repair in irradiated bone using autogenous bone graft associated with platelet-rich plasma in rabbit model. Twelve New Zealand White rabbits were divided into two equal groups: irradiated (I) and non-irradiated (II), which were divided into subgroups: control (left tibiae) and PRP (right tibiae). The irradiated group received a single dose of 15 Gy in the tibiae bone. After forty-five days, in groups I and II, were created lesions in the tibiae, with trephine of 5 mm of diameter. The lesions were filled with autogenous bone grafts with PRP (test group) or without PRP (control group). After four weeks, the animals were sacrificed and the grafted regions were removed, fixed in formalin in PBS, demineralized in EDTA and embedded in paraffin. The histological images were captured at 4X magnification and submitted to the process of Targeting Interactive, as recommended by Oliveira et al. (2006). The region of bone matrix was called Region of Interest (ROI) and the percentage of matrix by area was obtained and analyzed through algorithms developed in the programming environment Scilab. The data were processed using the tests Kolmogrorov-Smirnov and paired ttest student and not paired. The statistical analysis of irradiated and nonirradiated groups showed no significant difference between test and control groups. Also, there s no significant difference between groups irradiated and non-irradiated. According to data obtained, the use of autogenous bone grafts associated with the PRP did not contribute significantly in the repair of irradiated bone.

The compatibility among different root canal sealers and luting agents for post cementation is an important aspect that must be considered in the prosthetic rehabilitation. This study evaluated the effect of different root canal sealers on the bond strength of fiberglass posts luted with four different luting agents. One hundred and thirty one human canines were selected, the crowns removed and the roots instrumented. For obturation, the specimens were randomly divided into 3 groups (n=44) accordingly to the root sealers: E - zinc oxide and eugenol-based; H -calcium hydroxide-based and R -resinous cement. Then, root canals were prepared with a drill of the post system. The initial groups were subdivided into four subgroups (n=11) accordingly to the luting agents for the cementation of posts: P - zinc phosphate cement, I -resinmodified glass ionomer cement, RC -resin cement and RA - self-adhesive resin cement. Roots were cross-sectioned to obtain six 1-mm-thick slices that were submitted to micropush-out test. Data were analyzed using ANOVA and Tukey tests. The interaction among root canal sealer, luting agent and region of the root had significant effect on the bond strength of fiberglass posts (P<0.05). Zinc oxide and eugenol-based cement interfered negatively with the bond strength to root dentine when conventional and self-adhesive resin cements were used along its full length. Lower bond strength values were obtained with the interaction between zinc oxide and eugenol and conventional resin cement, while higher values were obtained with the interaction between calcium hydroxide and self-adhesive resin cement. Bond strength decreased from crown to apex only in resin cement groups.

Psoriasis is a chronic dermatologic disease that comets at least 3% of the world population. In the tropical countries, such as Brazil, it is considered an important factor of social exclusion. The clinic manifestation presents mainly papules and white plaque that are easily removed leaving at its place many small bleeding points known as Austpits sign. The disease may shows different clinic pattern and it can be find in different stage described as evaluative or acute and stable or asymptomatic. Oral manifestation is still a controversy in the literature. It has been described by some authors in clinical case reports as white or erythematous lesions, ulcers and descamative papules. Some of these reports tend to establish a direct relationship between the dermatologic manifestation and geographic and fissured tongues and others could not find the same occurrence. In the present study all the patients attended to the psoriasis ambulatory of the Uberlândia Federal University medical school passed into an oral exam in a period of 12 months. 36 patients were included in this study because they had been examined two times or more in a period bigger than three weeks, allowing establishing a relationship between the disease clinical stage and the oral manifestation. The oral lesions found in this study were two white plaques in the jugal mucosa, seven erythematous areas in the hard palate and two angular queilites, six fissured and one one association of geographic and fissured tongue. After all, it was not possible to make any specific association between dermatologic and oral manifestation because some oral lesions were present in both stage of psoriasis and otherwise, some were present in a stable stage and disappeared in the progressive. Also the incidence of the oral lesion identified in this study was similar to that found in a normal population.

The aim of this study was to evaluate the effect of replacement and repair of unsatisfactory maxillary mucosa supported and mandibular implant retained overdenture on the masticatory function, quality of life and satisfaction of completely bimaxillary edentulous patients. Thirteen completely bimaxillary edentulous patients rehabilitated with complete mucosa supported maxillary dentures and mandibular implant retained overdentures had their dentures assessed according to esthetic physical and functional criteria. Three patients required only repair to dentures and 10 patients needed to have them replaced. The clinical and laboratory procedures were standardized and performed by a single operator. Laboratory tests for analyzing masticatory performance were performed by means of masticating the food simulator Optocal for 40 cycles. The index was obtained by calculating the percentage of reduction in the mean geometrical diameter of the masticated particles. Masticatory ability, satisfaction with dentures and quality of life related to oral health was evaluated by means of questionnaires. The tests were performed and questionnaires applied before, and one month after the patient had adapted to the new dentures. The masticatory performance data were statistically analyzed by means of the paired Student s-t test. For the other evaluations, the Wilcoxon test was used (a=.05). There was no statistically significant improvement in masticatory function before and after denture replacements and repairs (P=0.53). Masticatory ability presented no statistically significant difference, since the majority of patients had considered their masticatory function satisfactory. There was a statistically significant improvement in satisfaction with the dentures, stability, retention and esthetics, and as regards the questions with reference to quality of life related to oral health: retention of food under the dentures and difficulty with chewing certain foods. Within the limits of this study, it could be affirmed that the potential for grinding food and masticatory ability did not improve immediately after changing or repairing the unsatisfactory dentures. However, the patient s satisfaction and aspects of quality of life improved significantly after denture replacement and repair.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

This research has been based on a quantitative evaluation, and has aimed at measuring possible discrepancies between the maxillary (upper jaw) and mandible (lower jaw) positions of Centrical Relation (CR) and Maximum Interspitting (MI), using computed tomography volumetric cone beam (cone method beam).The sample of study has consisted of 20 young adults and asymptomatic which has been equally divided into four groups, the first group has been formed by patients with normal occlusion and the other three groups, by individuals with bad occlusion from class I, II and III, of Angle. Those patients had been initially subjected to carry out a device made of a type of resin "JIG of Lucia" in order to have their jaws handled and maintained in CR whenever desired. Patients had been referred to a clinic of Dental Radiology where they were submitted to two cone beam tomographic examinations in NewTom 3G device, the first one having occlusion in MI and second one by using "JIG's previously made. Evaluations were made in both frontal and lateral tomographic image cuta, showing the condyle articular fossa relation; as well as in cutting side to investigate the relationship anteroposterior between the upper central incisor (tooth 11) and the respective lower incisor in alignment with. Those images had been processed in the own software of the 3G Newtom device (Software QR NNT Version 2.00) and 10 tomographic image cuts were obtained per patient being four lateral sides and four front of the ATM's (in CR and MI, on both sides right and left) and two lateral sides of the incisors (CR and MI). Through the use of tools for linear and angular measures of another software unit Newtom 3G (Basic 3G) other 520 measurements were obtained and taken for statistical analysis. For that, T tests of Student and Tukey at 5% level were applied. Differences shown in whole sample were not statistically significant in despite of the fact that in 94.5% of the measuring evaluations taken between placements CR and MI intra and inter groups and between the right and left sides. Only the anteroposterior relation among incisors in the normal group had shown statistical significance between positions in CR and MI. This research has been based on a quantitative evaluation, and has aimed at measuring possible discrepancies between the maxillary (upper jaw) and mandible (lower jaw) positions of Centrical Relation (CR) and Maximum Interspitting (MI), using computed tomography volumetric cone beam (cone method beam).