Repositório RCAAP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Primary stability and the type of surface roughness have a strong influence on the dental implants osseointegration. During implant placement, damage on the prosthetic connection and implant surface may occur. Due to the deformations in this portion of the implants, this work analyzed the effects of implant insertion into bone on the surface roughness parameters for the same surface treatment applied by the same manufacturer to implants with different macro-designs and evaluated the levels of deformation in external hexagon (EH) connections subjected to internal toque. For the surface analysis, three groups of titanium implants with different macro-designs were investigated using laser interferometry and scanning electron microscopy. Relevant surface roughness parameters were calculated for different regions of each implant before (B) and after (A) insertion into pork ribs. For the deformation of EH connections, two types of implants (S and N) were used and internal torque were applied. The internal distance (ID), internal area (IA) and external area (EA) of the EH were obtained. The tops of the threads of all B implants had very similar roughness parameters, independent of the geometry of the implant, after bone insertion, this was the region that presented significant alterations. In contrast, the flanks and valleys of the threads presented larger irregularities (Sa) with higher slopes (Sdq) on all B implants, particularly for implants with threads with smaller heights. Levels of EH deformation were greater in the S group as compared with the N group. This preliminary study demonstrated surface damage of the implants after the installation process by the changes observed on roughness parameters, which were affected by the macrogeometry. The EH may be affected by different internal torque levels.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Oral leukoplakia (LB) is the main precancerous lesions of the oral cavity. The diagnosis must be confirmed by histological findings, to exclude any alteration of the oral mucosa and verify signs of malignancy, as well as gradations of epithelial dysplasia. The WNT/β-catenin pathway comprise the regulation of a wide variety of physiological processes in different species, with a decisive role in embryonic development, cell proliferation and differentiation. Alterations in components of this pathway have also been reported in neoplasms of the oral cavity and precancerous disorders of oral mucosa. The objective of this study was to identify the pattern of gene transcription (functional expression) belonging to the signaling pathway WNT/β-catenin and their relationship with their gene products in a tissue sample of LB and its relationship with clinicopathological factors considered markers of malignant transformation. For this purpose, a sample of LB was selected in patients treated at the oral diagnosis department (FOUFU) from 1994 to 2014. The evaluation of gene and protein expression were performed by qPCR and immunohistochemistry method respectively. Most patients belonged to males (53.8%) and had a median age of 56 years, ranging from 34-93 years. Most of the patients were smokers and the place most affected was the cheek. Approximately 75% of patients had LBR and in six cases was evidenced malignant transformation of the lesion. Initial lesion size was a factor associated with an increased risk of malignant transformation. Overall, the relative expression of all genes was higher in the control group than in the group LB. It was found higher protein expression of WNT 1, β-catenin, c-Myc, CiclinD1 in normal mucosa than in group LB. For GSK3β, APC and E-cadherin was higher expression in the LB group than in the control group. The smoking cessation offers better prognosis for the patient, reflecting a clinical and histologic improvement of LB. In conclusion, the present study showed that a reduction in the expression of CCNTB1, CDH1 and APC may be a critical event in the progression and malignant transformation of LB and increased CCND1 expression in LAR can be considered a prognosis worsening factor of this disease.

The aim of this study was to verify masticatory performance, masticatory ability, nutritional status, satisfaction with denture, quality of life related to oral health, as well as the association between variables. Sixteen individuals from 30 to 76 years of age, of both genders, wearers of bimaxillary mucosupported complete dentures (MSD), were assessed before, immediately, three and six months after conversion of the mandibular denture into a mucosupported and implant retained denture (IRD), improving its retention and stability by means of two implants in the mandibular bone and a bar/clip system. Masticatory performance was analyzed using the Optocal food simulator test, masticated for 20 and 40 cycles. Masticatory ability by a questionnaire and the Visual Analogue Scale (VAS). Nutritional status was assessed by means of the Mini-Nutritional Assessment (MAN) questionnaire, and blood albumin, transferrin, total cholesterol, lymphyocyte and reactive C protein analyses. Satisfaction with the denture was assessed by means of the questionnaire and EVA. The OHIP-14Br questionnaire was used to evaluate the quality of life related to oral health. To be related masticatory performance test with other tests. The data collected were submitted to statistical analysis (α = .05) by means of the Friedman, Wilcoxon, student s-t test for paired samples, student s-t test for non-paired samples, Cochran s Q and Mann-Whitney s U tests. It was observed in masticatory performance that the individuals potential for chewing Optocal improved significantly after three months of immediate conversion of the mandibular MSD to IRD. In the masticatory ability analysis by the questionnaires and EVA, there was statistically significant difference only after six months. Masticatory performance had no relation with masticatory ability. Nutritional assessment by MAN demonstrated significant improvement six months after the conversion of MSD to IRD. In the hematologic exam, there was no statistically significant difference for albumin, transferrin, total cholesterol, reactive C protein and lymphocytes in the assessments performed before, three and six months after conversion. MAN and the hematologic exams showed no relation, however, no patient was classified as undernourished by MAN, and the same could be observed from the hematologic exam. Satisfaction with the mandibular denture rose from 43.755 to 100% immediately after conversion, there being more complaint about the maxillary denture after the conversion (6.25% to 25% dissatisfaction). Quality of life related to oral health showed immediate improvement after the conversion from MSD to MSIRD, but statistically significant difference only occurred as from the three-month assessment. For the participants considered nourished by MAN, the mean of the masticatory performance index before mandibular denture conversion was 22.43%, while for those at risk for malnutrition it was 3.9%, and six months after the conversion this index rose to 33.75% and 19.93%, respectively. Satisfaction with the mandibular denture and the quality of life related to oral health presented no relation to the masticatory performance index.

The proportion of older people is growing faster than any other age group. Due to that, there is a growing interest in the oral health status of older people as the size of this population is increasing around the world. It must be remembered that oral mucosa shows essential functions that significantly affect patient general health. With aging process the oral mucosa becomes more susceptible to external stimuli in function of a reducing capacity epithelium regeneration and consequently expose the individual to various harmful and infectious agents coming trough oral cavity. These predisposing factors are alcohol, tobacco, medicaments, nutritional deficiency, chronic diseases, prostheses and infectious agents. However there are unlimited studies in the world mentioning the prevalence of oral mucosal lesions in elderly that have been essentially of clinical nature. Surveys about alterations which the diagnoses have been made by histopathologic exams have been seldom mentioned. The aim of this study was to achieve a cross-section epidemiologic study of elderly oral disease, basing on a survey of diagnosed cases on the Oral Pathology Laboratory of the Universidade Federal de Uberlandia between 1978 and 2006. In order to that, 8837 registered cases in the lab archives were investigated on this period (28years). From the entire sample, 9,5% of the cases, corresponding 838 biopsies, satisfy the 60 69 years, 70 -79 years, 80 89 years and 90 or more years of age and oral tissues location criteria. For the classification Neville et al,,., (2002) criteria were used with modifications, assembling into twelve categories. The results show the majority cases are concentrated on the youngest group, 60-69 years (514/838), female the gender most affected (470/838) and alveolar edge the most common location (125/838). The twelve categories identified on this sample presented the follow frequency: Infectious diseases (2,6%), proliferative non neoplasic lesions (36,5%), bone lesions (2,6%), benignant and malignant neoplasms (22,4%), cysts and odontogenic tumors (3,0%), non odontogenic cysts (1,1%), salivary gland diseases (3,7%), periodontal diseases (2,7%), physical and chemical injuries (6,0%), Epithelial non infectious and non neoplasic diseases (6,7%), immunologic and allergic diseases (2,9%), pulp and apical diseases (9,8%). Proliferative non neoplastic lesions were the predominat diagnostic group (36,5%) followed by benignant and malignant neoplasms (22,4%). The fibrous hyperplasia was the most frequent lesion (33,2%) followed by squamous cell carcinoma (13,6%)and apical cyst (5,4%). The twelve most frequent lesions were responsible for 72,5% of the entire sample.

In considering the wide use of the cephalometric analysis in the diagnosis of individuals with dentofacial deformities, the objective of this retrospective study was to evaluate the correlation between the surgical treatment suggested by the cephalometry and the actual orthognathic surgery performed in long face pattern individuals, and additionally to comparing the alterations among the averages of the cephalometric measurements obtained in the pre and postsurgical period. The sample was composed by 32 lateral pre and postsurgical x-rays of 16 individuals of both genders with average age of 29 years and 11 months. From the tracings in the x-rays it was evaluated: sagittal maxilo-mandibular relation, maxilo-mandibular relation, effective length of the maxilla, mandible, and facial heights, vertical relation, and also the dental relations to their apical bases. The averages of each pre and postsurgical variables were also compared using tests t of Student and Wilcoxon. The results had shown that it did not have a relation between the cephalometric diagnosis and the actual surgery performed. Since the long face pattern individuals present a great imbalance between the facial vertical components, in 93,75% of the cases they underwent a superior replacement of the maxilla associated or not to a mandible advancement and genioplasty. Regarding to the averages of the cephalometric values between the before and after-surgical measurements it had statistically significant difference (p<0,05) for: SNA, SNB, ANB, A' Pp - B' Pp, Nperp- A, Nperp-Pog, Co-A, Co-Gn, ENA-Me, SN.Gn, SN.GoMe, SN.Pp, Pp.Po and Pp.GoMe. After the data exam it was concluded that the cephalometric analysis, although integrant part of the diagnosis resources, separately, is not capable to predict the surgical treatment and must, always, be associated to the facial analysis.

This study evaluated the relationship between cephalometric planes and the true vertical line on lateral cephalograms obtained in natural head positioning, from individuals with different facial patterns. The sample comprised 28 individuals (15 females and 13 males), aged 17 to 37 years, with complete dentition at least up to the first molars without previous orthodontic/surgical treatment. The patients were divided into three groups according to the different facial patterns, namely Pattern I, Pattern II and Pattern III, according to Capelozza Filho (2004). Lateral cephalograms were obtained from the individuals in natural head positioning (NHP) with projection of a metallic line to define the true vertical line (TVL). After cephalometric tracing, classical reference planes (SN, Frankfurt plane, Palatal plane, Occlusal plane and Mandibular plane) were analyzed in relation to the TVL, in order to determine the correlation between cephalometric planes in facial patterns I, II and III. There was no statistically significant difference between values observed for the planes SN, FRANK, PP and GoGn for the three facial patterns investigated. The reference plane SN, widely employed in several cephalometric analyses, presented a variance of 25.9º. The horizontal planes in relation to the TVL did not present any specific behavior for each type of facial patter, suggesting that more than one reference plane should be employed in individuals with dentofacial deformity, as well as other measurements to allow a complementary sagittal evaluation.

The present work describes the demographic and clinic profile of 66 patients with oral lesions of paracoccidioidomycosis attended in a reference center for Oral Pathology, in the period between 1978 and 2006. There was predominance of middle-aged males, with large number of people with rural ocupation. In the oral cavity, most of the cases presented gingival lesions, followed by palate and lips. Very often, oral manifestations leaded to the diagnosis. Chronic multifocal form was predominant, with moderate systemic alterations. The low frequency of severe manifestations, in addition to the large number of patients without evident pulmonary alterations, was interpreted as evidence that oral lesions of paracoccidioidomycosis occur precociously. In addition, the high frequency of cases, as compared to previous works, suggests that the investigated area would be endemic to the mycosis. These hypotheses should be tested in future investigations.

The aim of this study was to analyze whether an orthognathic surgery could change the face profile attractiveness of individuals with dentofacial deformities. Fifty profile photographs of 05 individuals were classified into Standard II, 14 Standard III and 06 Long Face Standard, after that the submitted the orthognathic surgery. A group of evaluators, 05 plastic surgeons, 05 maxillofacial surgeons, 05 orthodontists and 05 laypeople, analyzed the facial attractiveness of the patients before and after surgery. The analysis was performed by the observation of presurgical and postsurgical photographs from the face profile of all patients, randomly arranged in an album. The evaluators classified the patients according to the following scores: aesthetic pleasant (scores 7, 8 and 9); aesthetic acceptable (scores 4, 5 and 6) and aesthetic unpleasant (scores 1, 2 and 3). The Wilcoxon test (p<0.05) demonstrated that the evaluators noted an improvement of the face attractiveness of all individuals and in 23 individuals significant differences were perceived between presurgical and postsurgical photographs. The age and gender of the patients had not an influence in the results. The lips, the chin and the chin-neck line were the most important aspects used to justify the unpleasant aesthetic appearance. According to the results of this study and the employed methodology it can be concluded that face profile changes by orthognathic surgery improved the attractiveness of the individuals with dentofacial deformities.

Osseointegrated implants have now been proved to be feasible. However, several factors still remain to be explained, particularly because of the large number of manufacturers and models. Although incidence is low, implant fractures are a clinical reality, and therefore researches are conducted in an endeavor to reduce their number. Objective: To test the hypothesis that the reduction in implant diameter reduces the maximum force required to attain the implant yield limit even when it is made in one piece. Materials and Methods: To test this hypothesis, three implant configurations (SIN) (n=10): HER, external hexagonal junction and regular diameter (3.75mm); HEE, external hexagonal junction and narrow diameter (3.25mm) and UNI, narrow one-piece (2.35mm) were tested. The maximum force at yield limit (N) for the implants was evaluated by means of the flexion test, with force applied perpendicular to the long axis of the implant, at the speed of 0.5 mm/min, in a mechanical test machine. The data were assed by means of the analysis of variance (ANOVA) and Tukey B tests for parametric groups (P<0.05). Results: Statistically significant differences were found between UNI and HER and HEE, and there were no statistically significant differences between the latter two. Conclusions: The UNI group presented statistically lower maximum resistance at the yield limit than the groups HEE and HER.

The objective of this study was to compare the biomechanical fixation and bone-to-implant contact (%BIC) between the OsseanTM, a bioceramic gritblasted and acid-etched surface versus a dual acid-etched implant surface (Control) in a beagle dog model. Control and OsseanTM implants (n=3) were subjected to a series of physico/chemical characterization tools including scanning electron microscopy (SEM), atomic force microscopy (AFM), and auger photoelectron spectroscopy (APS). The animal model comprised the placement of 72 implants along the proximal tibiae of 6 beagle dogs (36 per surface, 6 per limb, through bilateral sequenced procedures), which remained for 2 and 4 weeks implantation time. After euthanization, half the specimens were biomechanically tested (removal torque), and the other half was nondecalcified processed to ~30 mm thickness slides for histomorphologic and histomorphometric (%BIC) evaluation. ANOVA at 95% level of confidence and Tukey post-hoc test was utilized for multiple comparisons. The SEM and AFM showed that surface microtextures were qualitatively and quantitatively different, and that the OsseanTM surface presented higher submicrometer Ra and RMS values compared to Control surfaces. Ca and P was detected at the OsseanTM surface by APS. Higher degrees of bone organization were observed along the perimeter of the OsseanTM surface compared to Control, despite the nonsignificant differences in %BIC between surfaces (p > 0.16). Significantly higher removal torque was observed for the OsseanTM implants at both implantation times (p < 0.0001). According to the biomechanical and histomorphologic results, early wound healing was positively affected by the OsseanTM surface compared to the dual-acid etched surface.

This study evaluated the fracture strength of fiber-reinforced composite inlay fixed partial dentures according to the pontic distance and the type of fiberreinforcement. One hundred and twenty bovine incisors were selected and grounded with 600-grit silicon paper to get an incisor platform, simulating a human molar incisal surface. The teeth were included in polystyrene resin blocks and the periodontal ligament was simulated with polyether material in pairs with 2 different distances: d11- 11.0 mm of pontic distance and d18- 18.0 mm of pontic distance. Teeth were prepared, resulting in incisal-distal and incisal-mesial Class II boxes. Then, samples were restored with a standardized composite inlay adhesive fixed partial denture (AFPD) made in laboratory resin (Sinfony, 3M Espe), generating 4 groups: Int- direct fiber-reinforcement (Interlig, Angelus); FiLab- laboratory unidirectional fiber-glass bundle (Fibrex Medial) associated to a laboratory multidirectional fiber-glass bundle (Fibrex Junciona l, Lab Fibrex, Angelus); and FiPon- laboratory unidirectional fiber-glass bundle associated with pre-manufactured fiber-glass pontic (Fibrex Pontic, Angelus). The AFPD samples were fixed with dual-cure resin cement (Rely-X ARC) and after 24 hours were submitted to a mechanical testing machine with a compressive axial load at the center of the pontic, with a crosshead-speed of 0.5mm/minute. Fracture modes were classified according to 3 categories. Data were analyzed by two-way ANOVA and Tukey test (P <.05). The analysis revealed that the fiber-reinforcement (P <.001) and pontic distance (P <.001) were significant. The failures were most prevalent among resin and fiber, in absence of fractures of the fibers or dental structure. The mean fracture strength and standard deviation of the AFPDs groups were: d11: FiPon (681,8 ± 268,9 ), FiLab (537 ± 186,7), Int (370,4 ± 155,8) for d18: FiPon (939,4 ± 175,6), FiLab (666,1 ± 95,5) e Int (445,8 ± 49,7). The fracture strength was significantly higher in the 18.0 mm distance with FiPon. Use of unidirectional fiber-glass bundle associated with fiber-glass pontic increases the fracture resistance irrespective of the distances tested.

This study aimed to determine coronal leakage of root canals filling remnants when employing Sealapex , used or don t used temporary restorative materials Cotosol or Super Bonder, by means of differents microbial indicators. Thus, 32 single-rooted human teeth were used, which were shaped until the file size 50 and assigned to 4 groups. A group was used as control. In the study model, a platform was employed, which was split in two halves: an upper chamber where the microbial suspension containing the biological indicators was introduced (E. faecalis + S. aureus + P. aeruginosa + B. subtilis + C. albicans); and a lower chamber containing the culture medium Brain Heart Infusion, in which 3mm of the apical region of teeth were kept immersed. Interpretations of the time to occur microbial leakage were made daily for 60 days, using the turbidity of the culture medium which is indicative of microbial contamination, as a reference. The data obtained were submitted to the Kruskal-Wallis test. The results show that in the three: Group 1 - remaining obturation with Sealapex of 5mm; Group 2 - remaining obturation with Sealapex of 5mm and plug of 1mm Cotosol; Group 3 - remaining obturation with Sealapex of 5mm and plug of 1mm Super Bonder; didn t show statistical significant difference (p<0.05). In the group 1 didn t finding microbial leakage in 100% of the samples and for groups 2 and 3 in 87,5%.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

The purpose of this study was to compare the ability to induce palatal mucosa anesthesia and the anesthetic efficacy after superior alveolar posterior nerve block of two anesthetic solutions: 4% articaine with epinephrine 1:100,000 (Articaine-DFL) and 2% lidocaine with epinephrine 1:100,000 (Alphacaine-DFL), in a double-blind crossover manner. Eighteen healthy volunteers, aged 14 to 26 years, with non-irrupted superior third molar removal indications were selected. All procedures were executed in the morning at once, by the same oral and maxillofacial surgeon. The diffusion ability and the efficacy of anesthetic solutions were verified by the 11-Point Box Scale, administered two times for each solution: after incision and detachment and after suture. The anxiety degree was evaluated by Corah Dental Anxiety Scale. Data were analyzed trough Wilcoxon´s test (α= 0.05). All the median values for the 11-Point Box Scale were similar. Besides that there were no significant statistical differences between articaine and lidocaine solutions after incision and detachment (p= 0.329) neither after the surgical procedures (p= 0.393). Results showed that in healthy patients, both anesthetic solutions had the same diffusion to palatal mucosa, and 2% lidocaine with epinephrine 1:100,000 and 4% articaine with epinephrine 1:100,000 presented similar clinical behavior, thus choosing either solution does not change the quality of the non-irrupted superior third molars removal.

It is generally accepted that root canal treatment procedures should be confined within the root canal system. To achieve this objective the canal terminus must be detected accurately during canal preparation and precise control of working length during the process must be maintained. Several techniques have been used for determining the apical canal terminus including electronic methods. The purpose of this ex vivo vitro study was to evaluate the ability of apex locator Root ZX II to locate the CDC limit under radiographic and macroscopic analysis. Thirty seven extracted permanent human teeth that had not been endodontically treated previously were selected. After conventional access, patency of the root canal was carefully checked with a #6 file. After storage in 1% NaOCl for a period of 1 h, the cervical and the middle portions of the root canal were slightly enlarged with endodontic files and Gates-Glidden burs to remove the pulp tissue as completely as possible under thorough irrigation with 1% NaOC1. The electronic working length measurement was conducted with 1% NaOCl as canal irrigant and a K-type file fitting loosely in the apical third of the canal. To measure the canal length with Root ZX II, all the samples and 1 lip clip of the apex locator were mounted in an alginate model. A file attached to the file holder was slowly inserted into the root canal until the meter on the apex locator dial indicated the meter reading Apex. The file was then withdrawn until the flashing bar on the meter designated the 1 mark. After the measurements, the files were fixed with self-curing resin in the pulpal chamber. All teeth were removed from alginate and radiographed with a zero-degree inclination in buccolingual plane. A digital sensor records the X-ray image and transfers the image to a computer. The distance from the end of the file to apex was measured by three investigators, and recorded. Then, the apical 5 mm of the root was shaved along the long axis of the tooth until the file could be seen through a thin layer of dentin. The remaining layer was then carefully removed using a scalpel blade. Each specimen was photographed and the distance from the end of the file to CDC limit was measured microscopically by three investigators, independently. The obtained distances were compared using a paired samples t test to determine the accuracy. The mean distance between the apex locator working length and CDC limit was - 0.42 ± 0.45 mm. The CDC limit (± 0.5 mm) was located 83.78% of the times. The distance from the end of the file to apex measured on both radiographic (-0.95 ± 0.43 mm) and macroscopic examinations (- 0.93 ± 0.44 mm) showed no statistical differences (p>0.05). It was concluded that the meter reading 1 on Root ZX II display allowed 83.78% precision providing a safety margin to prevent unintentional overinstrumentation.

The relationship maxilomandibular used in the planning and execution of the prosthetic rehabilitation is controverted and usually linked to the complexity of the treatment. The purpose of the work was to determine the philosophy supplied by educators of the Brazilian Institutions of higher education of Dentistry (IheD) as for the relationship maxilomandibular in function of the type of treatment suitable prosthetic rehabilitation, besides defining the educator's profile. Questionnaire-research was used with five clinical sceneries of patients with discrepancies among centric relation (CR) and maximum habitual intercuspation (MHI) with the following characteristics: scenery (1) asymptomatic patient that needed to substitute total prosthesis; (2) - patient teething completes, however with signs and symptoms of temporomandibular dysfunction; (3) - asymptomatic patient with need of removable partial denture (RPD); (4) - asymptomatic patient with need of fixed denture of three posterior elements; (5) - asymptomatic patient with need of fixed denture of three anterior elements. Questionnaire research was a correspondent to 161 IheD, addressed for the educators of the occlusion areas, fixed prosthesis, partial and total removable prosthesis, and integrated clinic, totaly 805 questionnaires. The professional's profile questioned the area of the educator's performance, graduation, place philosophy was consolidated. They were received 124 questionnaires research of 68 IheD. In the 1st clinical scenery, 77% answered that the maximum intercuspation (MI) it should coincide with CR; 2nd scenery 32% answered that it eliminates the deviation and 50% other answer; 3rd scenery 50% answered that it would make RPD with to coincident MI with CR; 4th scenery 52% answered that it would accomplish the procedure in MHI; 5th scenery 38% answered that it would adjust the centric occlusion relation (COR), leaving the teeth out of contact. Most of the teachers (98%) it acts in the rehabilitation area, they possess master's degree and doctorate, with time of professional performance between 10 and 20 years, in schools different from where they graduated and they powder-graduated and they declare that his/her philosophy was established in the masters degree. It is ended that great diversity of philosophies exists used in IheD on which relationship maxilomandibular is the more recommended. The choice depends on the extension of the treatment employed prosthetic rehabilitation and of the presence of signs and symptoms of traumatic occlusion. The educators' philosophy was consolidated during to masters degree, and the teachers are masters and doctors of the area of oral rehabilitation.

The purpose of this study was to evaluate the cleanness condition of graduation students endodontic files as well as the knowledge about necessary cares for their reutilization. It was also evaluated three files cleaning forms related to endodontic treatments, with and without vitality and retreatments. In the first part of the study (questionnaire evaluation) 72.29% of the students registered on fifth to eighth semester answered four questions regarding the frequency that the files were used and sterilized, which cleaning form was used and which bio-safety cares were taken. With the evaluation of the answers gotten it can be observed the necessity to guide the students about the biosafety cares and the significance of carrying through the use control of each file, as well as its periodic substitution necessity. In the second research stage was evaluated 27 Kerr files series of 25 mm (15-40), of the students registered on fifth to eighth semester, with optic microscope Toolmaker`s (Mitutoyo Corporation) in a 40x increase, attributing values for the presence or absence of adhered debris in the surface of each millimeter of the file active section (0 absence; 1 debris presence on file points of sprinkled aspect of; 2 debris presence up to 50% and 3 presence in more than 50% of the surface). Only 20.14% of the evaluated sites were free of debris and when score 2 and 3 values were added (which represent visible presence debris with the naked eye) the value of 40, 20% was gotten, showing that the students are not carrying through the visual inspection after the instruments cleaning. In the last research stage eighteen files Kerr type series (15-40) of 25 mm (Dentsply/Malleifer) sterilized and ready for use, were divided in 3 groups corresponding to six endodontic treatments in teeth with pulp vitality, six teeth without pulp vitality and six with endodontic treatment necessity. During the vitality and non-vitality cases treatment the professional used sodium hypochlorite 2.5% as irrigating solution and saline solution for final irrigation, in retreatment cases beyond these solutions it was used eucalypt oil for guttapercha removal. When instrumentation was finished, the files were conditioned in a 100% humidity bottle and evaluated, following the described methodology, and after that they were submitted to one of the cleaning processes: file torsion against gauze damped in 70% alcohol, brush and detergent cleaning, and ultrasonic Cuba and detergent cleaning and evaluated again. All the tested cleaning processes promoted significant reduction in the debris values, however there was no method 100% effective in all analyzed situations.

The many factors in the development of gingival recessions make the diagnosis and the prognosis treatment of them difficult. This study checks clinically if gingival recessions are related to the existence of parafunctional dental contacts, to the width of the keratinized mucous and to dental alignment alteration. Among 23 adults of both sexes, 660 teeth divided by groups (molars, premolars, canines and incisors) were clinically examined according to the following parameter: to the existence of parafunctional dental contacts in a maximal habitual intercuspation (MHI), work and no work, bilaterally and in a centric relation; width of the keratinized mucous measured by a milimetric probe; and the dental alignment categorization as normal or by buccal. The results were analyzed by means of frequency distribution. Gingival recessions were found in 94 teeth (14, 2%), in which 71, 3% of them were in posterior teeth and 28, 7% in anterior teeth. The first superior premolars showed the most gingival recession incidence (25, 5%). Among the gingival recession teeth, 77, 6% demonstrated the width of the keratinized mucous < 2,0mm and 46, 8% were to buccal. The teeth that exhibited a gingival recession had at least a parafunctional contact were in 85%. It can be concluded that the gingival recession is associated to parafunctional contact occurrence and to the width of the keratinized mucous and dental alignment.