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Made available in DSpace on 2022-04-30T22:28:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-10-01 Introduction: The main strategy for the prevention of caries disease is the use of pit and fissure sealants, which are indicated for posterior occlusal surfaces that are difficult to clean and cannot be protected very well by fluoride. This strategy is considered to be very important in caries prevention, especially in patients at high cariogenic risk. Objective: Evaluate whether the count of colony forming units of S. mutans per cm2 on the occlusal surface of posterior permanent teeth changes after applying resin-based sealant. Methods: A study was conducted of 38 patients of both genders aged 18-30 years. The patients were at high cariogenic risk and had an indication of occlusal sealant application on at least one permanent posterior tooth. Two samples were taken of dental biofilm from the same teeth before (group T0) and after (group T1) applying sealant obtained by direct impression by tray technique with trypticase yeast extract, cysteine, sucrose with bacitracin (TYCSB), and agar previously made and solidified. The samples were incubated at 37 ºC for 48 hours. The colony forming units (CFU/cm2) were counted. The results were statistically analyzed with the Wilcoxon test at 95 % confidence. Results: Average expression in CFU/cm2 before applying the sealant (T0) and standard deviation was 13.48 (± 14.2), whereas after applying the sealant (T1) it was 5.37 (± 8.90). There was a statistical difference between the two measures T0 and T1 (p< 0.05). Conclusions: Sealant application on occlusal surfaces of posterior permanent teeth significantly reduces the count of CFU/cm2 of S. mutans. Universidad de Chile Facultad de Odontología Departamento de Odontología Restauradora Universidad Andres Bello Facultad de Odontología Universidad Autónoma de Chile Instituto de Ciencias Biomédicas Universidad Estadual Paulista Facultad de Odontología Departamento de Odontología Restauradora Universidad Politécnica y Artística del Paraguay Universidad de Chile. Facultad de Microbiología Dental Departamento de MEdicina y Patología Oral Universidad de Ciencias Médicas de La Habana Facultad de Ciencias Médicas “Victoria de Girón” Departamento de Estomatología General Integral Universidad Estadual Paulista Facultad de Odontología Departamento de Odontología Restauradora

Objective: To assess the six-month clinical outcome of restorations of non-carious cervical lesions (NCCL) with two composite resins: Bulk-Fill and nanohybrid resin. Materials and methods: Fifty-one patients, with three NCCLs each, were randomly allocated into three restoration groups: Tetric-N-Ceram Bulk-Fill (TB); Filtek Bulk-Fill (FB); y Filtek Z350XT (Z350). Adhesive techniques and restorative procedures were performed according to the manufacturers’ instructions for the different materials. A 4mm increment was applied in TB and FB, and increments of ≤2mm depth were applied in Z350. Restorations were assessed by two calibrated examiners at baseline and at six months according to the FDI World Dental Federation guidelines (1: excellent, 2: acceptable, 3: sufficient, 4: unsatisfactory, 5: unacceptable) in Marginal Staining (MS), Fracture-Retention (FR), Marginal Adaptation (MA), Postoperative Sensitivity (S) and Caries (C). Wilcoxon test was used for the comparison between baseline and 6 months, and Kruskal-Wallis for the comparison of the three groups at six months (95% significance). Results: Forty-six patients with a total of 138 restorations attended a check-up at six months and were evaluated with excellent clinical outcome. In MS, 91.2% for Z350 and 97.8% for FB and TB; in FR, 97.8% for Z350 and 100% for FB and TB; in MA, 95.6% for Z350, 97.8% for FB and 100% for TN; in S, 95.6% for all three groups; and 100% for C. No statistically significant differences were found between the three groups nor in the comparison between the baseline and 6 months (p>0.05) Conclusion: No significant differences are observed between the three groups of resins in the parameters of MS, MA, S, FR and C regarding clinical outcome at six months.

The aim of this study was to evaluate color longevity after a year of in-office bleaching with gel (6% hydrogen peroxide HP, LED blue/laser infrared activation system) compared to a 35% control concentration in a split-mouth study model.Thirty-one patients were initially treated. The bleaching procedure with 6% or 35% gel HP was performed randomly in the upper half arcade of each patient. The color was measured at baseline and at 1 week, 1 month, and 1 year using the spectrophotometer Vita Easyshade, Vita Bleached, and Vita classical Shade guide organized by value. During the 1-year recall, the color was assessed before and after dental prophylaxis.Only 27 patients were assessed in the 1-year recall. There was a significant difference in the ΔE between the two groups at all times assessed (P .011). The ΔL, Δa, and Δb showed significant difference between both groups at all assessed times (P .038). There was no significant difference between the ΔSGU at all times (P .05) except for the Vita bleachedguide postprophylaxis comparison (P .05).The two compounds remained effective at 1 year. When objectively evaluated, color difference between groups was found, not seen when subjectively determined.A low concentration hydrogen peroxide bleaching agent can reach good clinical results at 1 year of follow-up.

SUMMARY Objective: The aim of this blinded and randomized clinical trial was to compare two application protocols (one 36-minute application vs three 12-minute applications). We then assessed the effectiveness of the bleaching and any increase in sensitivity that was induced by bleaching via a split-mouth design. Methods and Materials: Thirty patients were treated. One group had a half arch of teeth treated with a traditional application protocol (group A: 3 × 12 minutes for two sessions). The other received an abbreviated protocol (group B: 1 × 36 minutes over two sessions). Two sessions were appointed with a two-day interval between them. The tooth color was registered at each session, as well as one week and one month after completing the treatment via a spectrophotometer. This measured L*, a*, and b*. This was also evaluated subjectively using the VITA classical A1-D4 guide and VITA Bleachedguide 3D-MASTER. Tooth sensitivity was registered according to the visual analogue scale (VAS) scale. Tooth color variation and sensitivity were compared between groups. Results: Both treatments changed tooth color vs baseline. The ΔE* = 5.71 ± 2.62 in group A, and ΔE* = 4.93 ± 2.09 in group B one month after completing the bleaching (p=0.20). No statistical differences were seen via subjective evaluations. There were no differences in tooth sensitivity between the groups. The absolute risk of sensitivity reported for both groups was 6.25% (p=0.298). The intensity by VAS was mild (p=1.00). Conclusions: We used hydrogen peroxide (6%) that was light activated with a hybrid LED/laser and two different protocols (one 36-minute application vs three 12-minute applications each for two sessions). These approaches were equally effective. There were no differences in absolute risk of sensitivity; both groups reported mild sensitivity.

The aim of this clinical randomized double-blind split-mouth study was to assess the effectiveness of a 6% hydrogen peroxide with nitrogen-doped titanium dioxide light activated bleaching agent.31 patients were treated with: one upper hemiarcade with a 35% hydrogen peroxide bleaching agent and the other hemiarcade with a 6% hydrogen peroxide. Two applications were completed each treatment session and three sessions were appointed, with one week interval between them. Tooth colour was registered each session and 1 week and 1 months after completing the treatment by spectrophotometer, registering parameters L*, a* and b*, and subjectively using VITA Classic guide. Tooth sensitivity was registered by VAS and patient satisfaction and self-perception result was determined using OHIP-14. Tooth colour variation and sensitivity were compared between both bleaching agents.Both treatment showed a change between baseline colour and all check-points with a ΔE=5.57 for 6% and of ΔE=7.98 for the 35% one month after completing the (p0.05). No statistical differences were seen when subjective evaluations were compared. Also, no differences were seen in tooth sensitivity between bleaching agents. OHIP-14 questionnaire demonstrated a significant change for all patients after bleaching.A 6% hydrogen peroxide with nitrogen-doped titanium dioxide light activated agent is effective for tooth bleaching, reaching a ΔE of 5.57 one month after completing the treatment, with no clinical differences to a 35% agent neither in colour change or in tooth sensitivity.A low concentration hydrogen peroxide bleaching agent may reach good clinical results with less adverse effects.

SUMMARY Objective: This randomized clinical trial evaluated the effect of 35% hydrogen peroxide in comparison with 37% carbamide peroxide in a nonvital bleaching technique of “walking bleaching” (four sessions of treatment) on periodontal markers: nuclear factor kappa B-ligand (RANK-L—process of root resorption marker) and interleukin 1β (IL-1β—inflammatory response marker). Methods and Materials: Fifty volunteers presenting with discoloration of nonvital teeth and endodontic treatment in good condition participated. Fifty teeth were randomly divided into two study groups according to bleaching gel: HP = 35% hydrogen peroxide (n=25) and 37% carbamide peroxide (n=25). Nonvital bleaching was performed with a walking bleaching technique consisting of four sessions of bleach application. Gingival crevicular fluid samples were taken in order to quantify the RANK-L and IL-1β levels by enzyme-linked immunosorbent assay. Samples were obtained from six periodontal sites for each bleached tooth: three vestibular and three palatine (mesial, middle, and distal) at seven time periods: baseline, after each of the four sessions of nonvital bleaching, at one week, and at one month after nonvital bleaching. Tooth color variations were analyzed in each session by VITA Bleachedguide 3D-MASTER (ΔSGU). Results: Significant increments in the RANK-L and IL-1β levels were detected in each evaluated time compared with baseline (p Conclusions: Nonvital bleaching induced a significant increment in the RANK-L and IL-1β levels in periodontal tissues around bleached, nonvital teeth.

The aim of this double-blind clinical trial was to assess the longevity of repairs to localized clinical defects in composite resin restorations that were initially planned to be treated with a restoration replacement.Twenty-eight patients aged 18-80 years old with 50 composite resin restorations (CR) were recruited. The restorations with localized, marginal, anatomical deficiencies and/or secondary caries adjacent to CR that were "clinically judged" to be suitable for repair or replacement according to the USPHS criteria were randomly assigned to Repair (n=25) or Replacement (n=25) groups, and the quality of the restorations was scored according to the modified USPHS criteria. The restorations were blind and two examiners scored them at baseline (Cohen Kappa agreement score 0.74) and at ten years (Cohen Kappa agreement score 0.87) restorations. Wilcoxon tests were performed for comparisons within the same group (95% CI), and Friedman tests were utilized for multiple comparisons between the different years within each group.Over the decade, the two groups behaved similarly on the parameters of marginal adaptation (MA) (p0.05), secondary caries (SC) (p0.05), anatomy (A) (p0.05), and colour (C) (p0.05).Given that the MA, SC, A and C parameters behaved similarly in both groups, the repair of composite resins should be elected when clinically indicated, because it is a minimally invasive treatment that can consistently increase the longevity of restorations.The repair of defective composite resins as an alternative treatment to increase their longevity proved to be a safe and effective treatment in the long term.

SUMMARY Objectives: The aim of this study was to clinically evaluate posterior amalgam and resin composite restorations refurbished over a period of 12 years by investigating the influence of refurbishing on the survival of restorations and comparing their behaviors with respect to controls. Methods and Materials: Thirty-four patients were enrolled, ages 18 to 80 years, with 174 restorations, 48 restorations of resin composite (RC), and 126 restorations of amalgam (AM). Restorations with localized defects in anatomy, roughness, luster, or marginal staining that were clinically judged as suitable for refurbishing according to US Public Health Service (USPHS) Ryge criteria were assigned to group A—refurbishing (n=85; 67 AM, 18 RC)—or group B—control (n=89; 59 AM, 30 RC); the quality of the restorations was evaluated blindly according to the modified USPHS criteria. Two observers conducted evaluations at the initial state (k=0.74) and after one to five, 10, and 12 years (k=0.88). Wilcoxon, Friedman, and Mantel-Cox tests were performed to compare the groups, respectively. Results: After 12 years, both groups experienced a similar decline, except for an evidently better performance in marginal adaptation in RC control (p=0.043) and in anatomy in AM refurbished (p=0.032). Conclusions: After 12 years, no difference was found in the clinical condition and longevity of the refurbished restorations compared to the control group.

To evaluate the clinical performance of refurbished resin composite restorations compared to untreated (negative control) restorations over a period of 10 years.26 subjects (having a total of 52 composite restorations) were recruited. All restorations in the refurbished group showed clinical features rated bravo according to modified USPHS criteria. Untreated restorations were those that had been deemed acceptable (alpha or bravo rated); these were used as controls. Two examiners performed assessments at baseline and during the 5th and 10th years after the intervention. Wilcoxon tests were performed for within-group comparisons, Friedman tests were used for multiple within-group comparisons, and Mann Whitney tests were used for between-groups comparisons. Kaplan-Meier survival curves were calculated, and the Mantel-Cox test was used to compare curves. P0.05 was considered statistically significant.In both groups, 10-year scores were significantly different from baseline scores in all clinical parameters except secondary caries. There were no statistically significant differences in the survival analysis of groups (log-rank test, P = 0.376). Refurbishing treatment improved the anatomy, roughness, luster, and marginal adaptation of restorations with a short-term effect, with most properties rated acceptable after 10 years of clinical service. The clinical characteristics were similar for all groups at the 10th year.

Aims: To assess the effects of application of an oxalic acid-based desensitizing agent before restoration of noncarious cervical lesions (NCCLs) with either a silorane-based or a methacrylate-based composite resin on decreasing the absolute risk and intensity of dentin hypersensitivity over the course of a 1-year follow-up. Methods: NCCLs in 31 patients (age range 24-66 years) were selected and randomly divided into four groups (n = 31 in all groups). In the Z250 and P90 groups, the restorations were performed with a methacrylate-based composite resin (Filtek Z250) and a silorane-based composite resin (Silorane P90), respectively. In the Z250 + OA and P90 + OA groups, the same composite resins were used, but an oxalic acid-based desensitizing agent (Desenssiv, SSWhite) was first applied. All NCCLs were evaluated before restoration (BR) and at 30, 60, 90, 180, and 360 days after treatment. Teeth sensitivity to evaporative and tactile stimuli was measured by a visual analog scale (VAS). The results were analyzed with statistical tools including Wilcoxon and Friedman tests for within-group comparisons and ANOVA and Bonferroni post hoc tests for between-group comparisons (P < .05). Results: Reduction in dentin hypersensitivity was observed for all treatment groups; however, these reductions were more pronounced when oxalic acid was applied before restoring the NCCL (P < .001). Complete elimination of pain was not achieved by any treatment modalities for the first 6 months; afterwards, in the groups that had received application of the oxalate-based desensitizing agent, the absolute risk of dentin hypersensitivity was significantly reduced (P < .01). Conclusion: The restoration of sensitive NCCLs with composite resins reduces dentin hypersensitivity. This reduction is more pronounced if an oxalic acid-based desensitizing agent is applied prior to the restoration. In addition, its application reduces the absolute risk of dentin hypersensitivity after 6 months of treatment.

SUMMARY Objective: The aim was to evaluate the color longevity after nine months of in-office bleaching with gel (6% hydrogen peroxide), to compare this to a control concentration of 35% in a split-mouth study model, and to assess the dental confidence and psychosocial impact on patients. Methods and Materials: Twenty-seven patients were assessed at the nine-month recall. The bleaching procedure with 6% or 35% hydrogen peroxide gel was performed randomly in the upper hemi-arch of each patient. The color was measured at baseline and at one week, one month, and nine months after the procedure, using the Vita Easyshade spectrophotometer, the Vita classical shade guide organized by value, and Vita Bleach Guide 3DMaster. Moreover, two surveys, OHIP-Esthetics and PIDAQ, were used to assess the esthetic self-perception and psychosocial impact of the bleaching procedure. During the nine-month recall, the color was assessed before and after dental prophylaxis. Results: Twenty-seven patients participated in the nine-month recall. There was a significant difference in ΔE between the two groups at all times assessed (p0.20). There was no significant difference in ΔSGU at all times (p>0.05). There was a significant difference in OHIP-Esthetics and PIDAQ sums compared with baseline scores (p Conclusion: The two compounds remained effective at nine months, with a slight rebound of color, and maintained their objective color difference but not the subjective color difference. Patients were satisfied with the bleaching procedure, and this had a positive impact on esthetic perception and a positive psychosocial impact at the nine-month recall.

In the last years the focus in dentistry has shifted to an "esthetic dentistry" approach, where patients are concerned about reaching a better look of their teeth. Vital tooth bleaching is a technique with immediate results, which improves the appearance and patient's self-esteem. The aim of this study was to recognize personality characteristics determined by the Millon Index of Personality Styles of participants looking for tooth bleaching and to correlate them to satisfaction with the treatment. Forty participants were included and filled out the Millon Index of Personality Styles form before treatment. Expectation about tooth bleaching was quantified from 1 to 5. Patients were treated with bleaching agent according to manufacturer's directions. One week after treatment, the patient's satisfaction was quantified from 1 to 5. Prevailing personality characteristics were determined. Expectations and satisfaction values of all patients were correlated with each of the presented personality scales by Spearman Rho test. Ten scales prevailed over their counterpart. Median of patient's expectation was 2 and satisfaction 4. Only the score of a single characteristic (extraversing) showed statistically significant correlation with patient satisfaction. Patients looking for tooth bleaching treatment seem to have common personality characteristics. Almost all of them wanted to achieve a moderate change in teeth color and the result of the treatment was usually satisfactory Resumo Ultimamente, o foco da Odontologia deslocou-se para uma "odontologia estética", em que os pacientes se preocupam em conseguir uma aparência melhor para seus dentes. O branqueamento vital é uma técnica com resultados imediatos que melhora aparência e auto-estima do paciente. O objetivo deste estudo foi detectar características de personalidade definidas pelo Índice Millon de Estilos de Personalidade de pessoas que buscaram branqueamento dental e correlacioná-las com a satisfação com o tratamento. Foram incluídos 40 participantes que preencheram o formulário do Índice Millon de Estilos de Personalidade antes do tratamento. A expectative sobre o branqueamento dental foi quantificada com valores de 1 a 5. Os pacientes foram tratados com agente branqueador de acordo com as instruções do fabricante. Uma semana depois o tratamento, a satisfação do paciente foi quantificada com valores de 1 a 5. Foram determinados as características predominantes. Os valores da expectativa e da satisfação foram correlacionados com cada escala de personalidade apresentada através do teste de Spearman Rho. Dez escalas prevaleceram sobre a sua contrapartida. A mediana das expectativas foi 2 e das satisfações foi 4. O valor de uma característica apenas (extraversão) apresentou correlação estatisticamente significante com a satisfação do paciente. Os pacientes que buscam o branqueamento dental parecem ter características comuns de personalidade. Quase todos queriam conseguir uma mudança moderada na cor dos dentes e o resultado do tratamento foi geralmente satisfatório.

Introduction: the goal of this literature review is to analyze the findings included in the literature concerning different alternatives to increase longevity of resin-based composite restorations and their adhesive bond. Methods: bibliographies in the EBSCO database (Elton B Stephens Company) were reviewed using the following key words: "composite repair bond strength"; "restorations sealing"; composite restorations longevity"; "restorations refurbishment"; "composite bond strategy"; "dental adhesive collagen cross linking"; "proanthocyanidin dentin bond strength"; "multiple layer dentin bond strength", and "dentin adhesive evaporation bond strength". Clinical and laboratory results were analyzed in terms of repairing, sealing, and refurbishing defective restorations, in addition to improvements in impregnation of adhesive surfaces, resistance of adhesive polymers, and the progress recently made concerning resistance to hydrolytic collagen degradation. Results: repairing, sealing, or refurbishing defective restorations allow keeping tooth structure healthy, reducing potential damage to dental pulp, as well as operatory pain, often caused without anesthetics. New bonding management techniques provide adhesive procedures with increased longevity. Conclusions: repairing, refurbishing, or sealing defective composite resins increase the longevity of restorations and restored teeth by using minimally invasive dental techniques. Other methods, such as improving impregnation of adhesive surfaces, increasing adhesive polymers strength, and hydrolytic degradation of collagen are promising advances that modify the management of bonding techniques, providing patients with restorative treatments of increased longevity. RESUMEN. Introducción: el objetivo de esta revisión es analizar los resultados de las diferentes alternativas que presenta la literatura para incrementar la longevidad de las restauraciones con base a resinas compuestas. Métodos: fueron revisadas las bibliografías en la base de datos EBSCO (Elton B Stephens Company), en idioma inglés bajo los siguientes acrónimos " composite repair bond strengh"; "restorations sealing"; composite restorations longevity; "restorations refurbishment"; "composite bond estrategy"; "dental adhesive collagen cross linking"; "proanthocyanidin dentin bond strength";" multiple layer dentin bond strength"; and "dentin adhesive evaporation bond strength". Se examinan los resultados clínicos y de laboratorio de reparación, sellado y remodelado de restauraciones defectuosas, además de las mejoras en la impregnación de las superficies adhesivas, la resistencia de los polímeros adhesivos y los avances en el aumento de la resistencia a la degradación hidrolítica del colágeno. Resultados: la reparación, sellado y remodelado de restauraciones defectuosas permite la preservación de estructura dentaria sana, reducción del potencial daño a la pulpa dental y reducción del dolor operatorio, la mayoría de las veces efectuado sin uso de anestésicos. Nuevas técnicas para el manejo de la adhesión proporcionan incremento en la longevidad de los procedimientos adhesivos. Conclusiones: la reparación, remodelado y sellado de resinas compuestas defectuosas, incrementa la longevidad de las restauraciones y de los dientes restaurados con la aplicación de técnicas de odontología mínimamente invasiva. Adicionalmente otras metodologías, tales como mejoras en la impregnación de las superficies adhesivas, aumento de la resistencia de los polímeros adhesivos e incremento de la resistencia a la degradación hidrolítica del colágeno constituyen promisorios avances que modifican el manejo de las técnicas adhesivas, que permitirá ofrecer tratamientos restauradores de mayor longevidad a la población.

Introduction: ameloblasts are cells responsible for the production and mineralization of the organic matrix of enamel through several stages: pre-secretory, secretory, transition, and maturation. The organic matrix components are produced in the secretory phase. In the maturation phase, the organic component is removed and the mineralization process starts. This process requires the involvement of matrix metalloproteinase 20 (MMP-20), also called enamelysin. Several studies have shown the presence of MMP-20 in tooth development and its relationship to alterations in enamel formation. The objective was: to classify the different studies and laboratory techniques used to demonstrate the involvement of enamelysin in tooth development and its relation to pathologies during enamel formation. Methods: a systematic review was conducted with the following bibliographic databases: PubMed, Science-Direct, Hinari, and SciELO, in order to classify the different studies related to the involvement of MMP-20 in tooth development and the methods to detect its expression, between the years of 2009 and 2014. Results and conclusions: 11 in vitro models show that MMP-20 has specific cleavage sites for enamel matrix proteins. This process is altered by chemical composition, ions, and the presence of hydroxyapatite. Enamel morphology is altered in the knockout models. In human studies, MMP-20 has been associated with increased susceptibility to dental caries, enamel thickness, and dental agenesis. RESUMEN. Introducción: el ameloblasto es la célula encargada de la producción y mineralización de la matriz orgánica del esmalte. Atraviesa varias etapas: la fase pre-secretora, secretora, de transición y maduración. En la fase secretora se producen los componentes de la matriz orgánica. En la fase de maduración se elimina el componente orgánico y se inicia el proceso de mineralización. Este proceso requiere de la participación de la metaloproteinasa de matriz 20 (MMP-20) o también llamada enamelisina. Diversos estudios demuestran la presencia de MMP-20 en el desarrollo dentario y su relación con alteraciones en la formación del esmalte. El objeto fue clasificar los diferentes estudios y técnicas de laboratorio empleadas que demuestren la participación de enamelisina en el desarrollo dentario y su relación con patologías en la formación del esmalte. Métodos: se realizó una revisión sistemática de la literatura con las siguientes bases bibliográficas: PubMed, Science-Direct, Hinari y SciELO, con el fin de clasificar los diferentes estudios relacionados con la participación de MMP-20 en el desarrollo dental y los métodos utilizados para detectar su expresión, entre los años de 2009 a 2014. Resultados y conclusiones: los modelos in vitro evidencian que MMP-20 tiene sitios específicos de escisión para las proteínas de matriz de esmalte. Este proceso se ve alterado por la composición química, iones, y la presencia de hidroxiapatita. En los modelos knockout la morfología del esmalte está alterada. En los estudios en humanos, se ha relacionado la MMP-20 con una mayor susceptibilidad de caries dental, el grosor completo de esmalte y agenesias dentales.

Made available in DSpace on 2015-08-06T16:14:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-12-01. Added 1 bitstream(s) on 2015-08-06T16:44:20Z : No. of bitstreams: 1 S1677-32252013000400004.pdf: 828129 bytes, checksum: 8440a74c0e44640d3dcaf74ae6e2e357 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) AIM: To correlate the tray technique for isolation and counting of Streptococcus mutans over dental restoration with the toothpick technique. METHODS: Forty 18-50-year-old patients of both genders with high cariogenic risk were selected. Inclusion criteria were: occlusal restoration evaluated as alpha, according to the Ryge's criteria (examiner' Cohen-Kappa 0.8) and 2 years old maximum age. Each patient provided a saliva sample (control group S) and two samples of dental biofilm from amalgam or resin-based composite restorations in the same patient, one obtained with the toothpick technique (group TT), and the other from homologous tooth restoration with the tray technique (group TR). This method involves only a direct impression on the occlusal surfaces by a section of a fluoride tray with trypticase yeast extract cysteine sucrose with bacitracin (TYCSB) agar previously prepared and solidified. The samples were incubated at 37 ºC for 48 h and the colony-forming units (CFU) were counted. The results were statistically analyzed with SPSS software using the linear regression method at 95% confidence level. RESULTS: TR was able to isolate S. mutans, and there was a significant positive correlation (r=0.95) with TT. There was no significant correlation between TR and control group S (r=0.47). CONCLUSIONS: TR was able to isolate and count S. mutans from the dental biofilm of dental restorations with a significant correlation with the TT group. University of Chile Operative Dentistry, Dental School Department of Restorative Dentistry University of Chile Microbiology Dental School Department of Medicine and Oral Pathology Univ Estadual Paulista Araraquara Dental School Department of Restorative Dentistry Univ Estadual Paulista Araraquara Dental School Department of Restorative Dentistry

Made available in DSpace on 2015-08-06T16:14:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-01. Added 1 bitstream(s) on 2015-08-06T16:44:22Z : No. of bitstreams: 1 S1677-32252015000100005.pdf: 134071 bytes, checksum: 263b63b4eed83b1d31bca3dceb5c4076 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) AIM: To compare the number of colony forming units CFU and agar adherence of S. mutans on amalgam AM and resin composite RC occlusal restorations. Sixty-five healthy patients older than 18 years with high caries risk who had at least one occlusal AM and RC restorations n=130 were selected. METHODS: The restorations were evaluated according to the alpha Ryge criteria Cohen-Kappa 0.8. For each patient, a biofilm sample was taken using an impression tray technique with previously loaded with solid trypticase yeast extract cysteine sucrose with bacitracin agar placed over the AM restorations and RC restorations in the same patients. The tray was placed inside an oven at 37 °C for 48 h, and the S. mutans count was then performed. Data were analyzed with the test Wilcoxon with a 95% confidence level. RESULTS: RC restorations had statistically significant higher number of CFU of S. mutans than AM restorations p

ResumenLa causa de fracaso más común de los postes de fibra es su desalojo, principalmente debido a la compleja adhesión dentro del conducto radicular. El principal objetivo de este estudio fue determinar si existe diferencia significativa en la resistencia adhesiva mediante el test push-out en la cementación de postes de fibra con RelyX U-200® (U200) y Core Paste XP® (CPX) en diferentes regiones radiculares.Material y métodosSe seleccionaron 40 premolares, se seccionaron a 15mm del ápice, fueron tratados endodóncicamente y fueron divididos aleatoriamente en 2 grupos de 20, a los cuales se les cementó un poste de fibra translúcido Exacto® con U200 y CPX. Después de 24h cada muestra fue seccionada transversalmente a nivel cervical, medio y apical. Fueron sometidas al test de push-out mediante la máquina Tinius Olsen HK5-S para cuantificar la resistencia adhesiva en megapascales. Se utilizó el test Shapiro-Wilk, test de ANOVA de 2 factores y Tukey con un nivel de significación del 95%.ResultadosNo hubo diferencia significativa de ambos cementos (p=0,457), pero sí hubo diferencia cuando se comparó el tipo de cemento y la región; CPX presentó valor significativamente mayor en el tercio cervical (p

SUMMARY Purpose The objective of this study was to clinically evaluate sealed composite restorations after 10 years and compare their behavior with respect to controls. Methods and Materials The cohort consisted of 20 patients aged 18 to 80 years with 80 composite restorations. All participants in the sealing and no-treatment groups presented with clinical features for the marginal adaptation that deviated from the ideal and were rated Bravo (United States Public Health Service criteria). Composites with Alfa values for the marginal adaptation were used as the positive control. Results The marginal adaptation behavior was similar between the sealing and control (+) groups, with a high frequency of Bravo values in the 10th year (80% and 51%, respectively). Most of the no-treatment (-) group maintained the Bravo values (91%) for 10 years, although some restorations (9%) progressed to Charlie values. The anatomy parameter differed significantly between the first and 10th years, with deterioration in all three groups (p0.05). Conclusions Sealing the margins of the composite resin restorations had no significant effect compared with the control groups, under the conditions of this study. Sealing the restorations substantially improved the marginal staining and marginal adaptation parameters, although by the tenth year they were similar to the group without intervention.

ResumenLa aplicación de adhesivos dentarios autograbantes que contienen 10-metacriloxidecilfosfato dihidrogenado supera la resistencia a la biodegradación de la interfase adhesiva de los sistemas tradicionales de grabado total. El mecanismo de acción se basa en la formación de múltiples nanocapas de calcio unido a 2 moléculas 10-metacriloxidecilfosfato dihidrogenado sobre la dentina; estas múltiples capas de 3,5nm son las que protegerían las fibras colágenas del fenómeno de hidrólisis. Las nanocapas explicarían su alta estabilidad en el tiempo y la fortaleza de la unión, probadas tanto en estudios clínicos como de laboratorio. La interacción con la hidroxiapatita sucede con ácidos de pH bajos, pero mayores que los tradicionales, por lo que surge la necesidad de recomendar el grabado selectivo previo del esmalte. El uso de metacriloxidecilfosfato dihidrogenado permite el cambio de filosofía adhesiva desde el grabado total a la integración adhesiva de la dentina.AbstractApplying self-etching dental adhesives containing 10-MDP overcomes the resistance to biodegradation of the adhesive interface of traditional total etch. The mechanism of action is based on the formation of multiple nano-layers of calcium and two molecules of 10-MDP on the dentin surface. These multiple layers of 3.5nm protect the collagen fibers from hydrolysis phenomenon. The nano-layer explains its high stability and bond strength over time, tested both by clinical and laboratory studies. Hydroxyapatite interaction occurs with acids of low pH, but are higher than traditional, thus increasing the need to recommend the previous selective etching of the enamel. The use of MDP allows a change of philosophy from the total-etch adhesive to adhesive integration of the dentin.

The aim of this study was to compare ex vivo filtration rate (hydraulic conductance) in human dentin discs mechanically treated with diamond and carbide burs of different grain size with or without acid etching. Method: 60 healthy third molars, recently extracted from patients aged 18-30 years, were cleaned, disinfected (0.1% thymol) and embedded in epoxy resin blocks. Dentin discs were obtained by cutting the occlusal surface with cylindrical rotary instruments, forming nine groups containing 12 specimens each: 1: fine grain (FG); 2: medium grain (MG); 3: coarse grain (CG); 4: carbide (C) burs; 5: FG with acid etching (AE); 6: MG with AE; 7: CG with AE; 8: C with AE; 9: only AE. Hydraulic conductance was determined in the experimental model under constant pressure of 200mm H2O. No difference in hydraulic conductance was observed among dentin discs treated with different types of burs (p = 0.5). Differences were found in the hydraulic conductance of etched and non-etched dentin discs (p0.001). The type of mechanical bur treatment does not affect dentin hydraulic conductance. Acid etching significantly increases dentin hydraulic conductance.

SUMMARY The aim of this prospective, blind, and randomized clinical trial was to assess the effectiveness of repair of localized clinical defects in amalgam restorations that were initially scheduled for replacement. A cohort of 20 patients with 40 (Class I and Class II) amalgam restorations that presented one or more clinical features that deviated from the ideal (Bravo or Charlie) according to US Public Health Service criteria, were randomly assigned to either the repair or the replacement group—A: repair, n = 19; and B: replacement, n = 21. Two examiners who had calibration expertise evaluated the restorations at baseline and 10 years after according to seven parameters: marginal occlusal adaptation, anatomic form, surface roughness, marginal staining, contact, secondary caries, and luster. After 10 years, 30 restorations (75%) were evaluated (Group A: n = 17; Group B: n = 13). Repaired and replaced amalgam restorations showed similar survival outcomes regarding marginal defects and secondary caries in patients with low and medium caries risk, and most of the restorations were considered clinically acceptable after 10 years. Repair treatment increased the potential for tooth longevity, using a minimally interventional procedure. All restorations trend to downgrade over time.

The aim of this study was to compare the bleaching efficacy of 35% hydrogen peroxide and 15% hydrogen peroxide with nitrogen-doped titanium dioxide catalysed by an LED-laser hybrid light. We studied 70 patients randomized to two groups. Tooth shade and pulpal sensitivity were registered. Group 1: 15% hydrogen peroxide with nitrogen-doped titanium dioxide. Group 2: 35% hydrogen peroxide. Both groups were activated by an LED-laser light. No significant differences were seen in shade change immediately, one week or one month after treatment (p > 0.05). Differences were seen in pulpal sensitivity (p < 0.05). The use of an LED-laser hybrid light to activate 15% hydrogen peroxide gel with N_TiO2 permits decreasing the peroxide concentration with similar aesthetic results and less pulpal sensitivity than using 35% hydrogen peroxide for bleaching teeth.

Introduction: ameloblasts are cells responsible for the production and mineralization of the organic matrix of enamel through several stages: pre-secretory, secretory, transition, and maturation. The organic matrix components are produced in the secretory phase. In the maturation phase, the organic component is removed and the mineralization process starts. This process requires the involvement of matrix metalloproteinase 20 (MMP-20), also called enamelysin. Several studies have shown the presence of MMP-20 in tooth development and its relationship to alterations in enamel formation. The objective was: to classify the different studies and laboratory techniques used to demonstrate the involvement of enamelysin in tooth development and its relation to pathologies during enamel formation. Methods: a systematic review was conducted with the following bibliographic databases: PubMed, Science-Direct, Hinari, and SciELO, in order to classify the different studies related to the involvement of MMP-20 in tooth development and the methods to detect its expression, between the years of 2009 and 2014. Results and conclusions: 11 in vitro models show that MMP-20 has specific cleavage sites for enamel matrix proteins. This process is altered by chemical composition, ions, and the presence of hydroxyapatite. Enamel morphology is altered in the knockout models. In human studies, MMP-20 has been associated with increased susceptibility to dental caries, enamel thickness, and dental agenesis.