Impact of oral-health-related quality of life and self-esteem on patients with missing maxillary lateral incisor after orthodontic space closure: a single-blinded, randomized, controlled trial.

BACKGROUND: The maxillary lateral incisor is one of the teeth most likely to suffer agenesis, resulting in spacing between the central incisor and the canine. OBJECTIVE: To compare maxillary lateral incisor agenesis with space closure treatment versus non-treatment based on measurements of the self-perceived oral-health-related quality of life (OHRQoL) and self-esteem of the participants. SUBJECTS AND METHODS: A total of 44 people, aged 17-49 years, with missing lateral incisors were randomly assigned to two groups (n = 22 in each)-a treated group in which the space was orthodontically closed (TG) and a control group that remained untreated (CG). Randomization was performed by a researcher who was not involved in the clinical part of the study. The outcomes were assessed using the Oral Health Impact Profile and Rosenberg's Self-Esteem Scale, which were applied before (phase 1) and after (phase 2) the orthodontic treatment in the TG, and at baseline (phase 1) and 12 months after (phase 2) in the CG. All the data were blindly evaluated, supporting the single-blinded design of the study. RESULTS: All participants finished the randomized controlled trial, and the demographic characteristics were similar between the groups. In phase 1, the levels of self-esteem and OHRQoL at baseline were similar (P = 0.079, P = 0.693, respectively). In phase 2, the self-esteem scores of the CG decreased and the OHRQoL increased (P = 0.005, P < 0.001, respectively), while self-esteem increased in the TG and the OHRQoL decreased (P < 0.001). The CG had lower scores than the TG for self-esteem, but the opposite was observed for OHRQoL (P < 0.001). LIMITATIONS: Information bias may have occurred. Since the questionnaires could not have been applied at the same time in both groups, the time difference between the two assessments may have led to random and systematic error. CONCLUSIONS: The spacing resulting from missing maxillary lateral incisors had a negative impact on the OHRQoL and self-esteem of the participants, while orthodontically closing those spaces had a positive impact on those aspects. CLINICAL TRIAL REGISTRATION: This study was not registered. PROTOCOL: The protocol was not published before trial commencement.

In vivo biocompatibility of silicon dioxide nanofilm used as antimicrobial agent on acrylic surface.

the focus ofthis study was to testthe hypothesisthatthere would be no difference betweenthe biocompatibility of silicon dioxide nanofilms used as antimicrobial agents. Sixty male Wistar rats were divided into 4 groups (n=15): Group C (Control,Polyethylene), Group AR (Acrylic Resin), Group NP (Acrylic Resin coated with NP-Liquid), Group BG (Acrylic Resin coated with Bacterlon).the animals were sacrificed with 7,15 and 30 days and tissues analyzed as regardsthe events of inflammatory infiltrate, edema, necrosis, granulation tissue, mutinucleated giant cells, fibroblasts and collagen. Kruskal-Wallis and Dunn tests was used (P<0.05). Intense inflammatory infiltrate was shown mainly in Groups BG and AR, with significant difference from Control Group inthe time interval of 7days (P=0.004). Necrosis demonstrated significant difference between Group BG and Control Group (P<0.05) inthe time intervals of 7 days. For collagen fibers,there was significant difference betweenthe Control Group and Groups AR and BG inthe time interval of 7 days (P=0.006), and between BG and Control Groups inthe time intervals of 15 days (P=0.010).the hypothesis was rejected. Bacterlon demonstratedthe lowest level, and NP-Liquid Glassthe highest level of tissue compatibility, and best cell repair.the coating with NP-Liquid Glass was demonstrated to be highly promising for clinical use.

Evaluation in vivo of biocompatibility of differents resin-modified cements for bonding orthodontic bands.

The focus of this study was to test the hypothesis that there would be no difference between the biocompatibility of resin-modified glass ionomer cements. Sixty male Wistar rats were selected and divided into four groups: Control Group; Crosslink Group; RMO Group and Transbond Group. The materials were inserted into rat subcutaneous tissue. After time intervals of 7, 15 and 30 days morphological analyses were performed. The histological parameters assessed were: inflammatory infiltrate intensity; reaction of multinucleated giant cells; edema; necrosis; granulation reaction; young fibroblasts and collagenization. The results obtained were statistically analyzed by the Kruskal-Wallis and Dunn test (P<0.05). After 7 days, Groups RMO and Transbond showed intense inflammatory infiltrate (P=0.004), only Group RMO presented greater expression of multinucleated giant cell reaction (P=0.003) compared with the control group. After the time intervals of 15 and 30 days, there was evidence of light/moderate inflammatory infiltrate, lower level of multinucleated giant cell reaction and thicker areas of young fibroblasts in all the groups. The hypothesis was rejected. The Crosslink cement provided good tissue response, since it demonstrated a lower level of inflammatory infiltrate and higher degree of collagenization, while RMO demonstrated the lowest level of biocompatibility.

Effect of Different Concentrations of Chlorhexidine in Glass-ionomer Cements on In Vivo Biocompatibility.

PURPOSE: To examine whether a difference exists between the in vivo biocompatibility of glass-ionomer cements (GICs) containing chlorhexidine (CHX) in different concentrations. MATERIALS AND METHODS: Eighty-four male Wistar rats were distributed into 7 groups (n = 12) and received subcutaneous implants of small tubes containing different materials, as follows: Ketac control (K), Ketac-CHX 10% (K10), Ketac-CHX 18% (K18), Resilience control (R), Resilience-CHX 10% (R10), Resilience-CHX 18% (R18), Control (polyethylene). The animals were then sacrificed on post-insertion days 7, 15 and 30, and tissues were examined under an optical microscope for inflammatory infiltrate, edema, necrosis, granulation tissue, multinucleated giant cells, and collagen fibers. The results were statistically analyzed using Kruskal-Wallis and Dunn's tests (p < 0.05). RESULTS: Groups K18 and R18 showed larger areas of intense inflammatory infiltrate, with significant differences between group C and groups K18 and R18 (p = 0.007) at 7 days, and between groups C and K18 (p = 0.017) at 15 days. In terms of tissue repair, groups K18 and R18 demonstrated a lower quantity of collagen fibers with significant differences from group C (p = 0.019) at 7 days, and between group K18 and group C (p = 0.021) at 15 days. CONCLUSION: The 18% concentration of CHX was shown to have a toxic effect. The 10% concentration of CHX was shown to be suitable for tissue contact. The addition of CHX to the glass-ionomer cements is a highly promising method for obtaining of an antibacterial GIC for use in clinical practice.

Ankyloglossia and malocclusion: A systematic review and meta-analysis.

BACKGROUND: Ankyloglossia is a congenital alteration that affects the tongue's mobility, influencing craniofacial development; however, its association with malocclusion is still unclear. This systematic review and meta-analysis investigated the association between ankyloglossia and malocclusion in patients. TYPES OF STUDIES REVIEWED: The authors conducted a systematic review and meta-analysis of observational studies that investigated the association between malocclusion and the presence of ankyloglossia in any age group, used any assessment tool to diagnose ankyloglossia, and considered all types of malocclusion. The authors conducted searches in 8 electronic databases through July 1, 2022. They used Joanna Briggs Institute appraisal tools to assess the methodological quality and the Grading of Recommendations, Assessment, Development and Evaluations approach to assess the certainty of the evidence. RESULTS: Eleven studies (5 cross-sectional, 6 case-control) included 2,904 patients and over 13 occlusal alterations. The certainty of the evidence ranged from low through very low. Patients with Angle Class III malocclusion had similar or more inserted lingual frenula than patients with Class I malocclusion (standard mean difference, 0.37; 95% CI, -0.50 to 1.25) and Class II malocclusion (standard mean difference, 0.55; 95% CI, -0.52 to 1.63). Patients with Class III malocclusion had clinically significant increased mouth opening reduction compared with patients with Class I malocclusion (mean difference, 6.67; 95% CI, 4.01 to 9.33) and Class II malocclusion (mean difference, 5.04; 95% CI, 2.35 to 7.72) patients. PRACTICAL IMPLICATIONS: There is uncertain evidence that ankyloglossia may be associated with the development of occlusal alterations. Ankyloglossia did not influence the Angle classification. Clinicians should closely follow children with ankyloglossia to evaluate whether this condition interferes with the occlusion. Future research should prospectively follow up on the long-term association between ankyloglossia and malocclusion. The protocol was registered a priori in the PROSPERO database (CRD42021248034). No amendments were deemed necessary after the registration of the protocol. Some subgroup analyses planned a priori were not possible, such as the severity of ankyloglossia, sex, and age, due to the lack of studies reporting data for these subgroups.

Analysis of Tissue Repair of a New Cement Based on Calcium and Strontium Aluminates: A Triple-Blinded, Randomized, Controlled Trial in an Animal Model.

OBJECTIVE: The focus of this triple-blind randomized study was to evaluate the biocompatibility of a new root canal filling sealer (RCFS) based on tristrontium aluminate and dodecacalcium hepta-aluminate in living tissue. MATERIAL AND METHODS: Forty-five Wistar rats (Rattus norvegicus) were divided into three groups: control (polyethylene), sealer (Bio-C Sealer, Londrina, PR, Brazil), and experimental (tristrontium aluminate and dodecacalcium hepta-aluminate). The tissues were analyzed under an optical microscope to assess different cellular events at different time intervals (7, 15, and 30 days). STATISTICAL ANALYSIS: Data were analyzed using the Kruskal-Wallis and Dunn (p < 0.05) tests. RESULTS: In the initial period, a moderate inflammatory infiltrate was observed, similar between the endodontic cements groups (p = 0.725). The intensity of the infiltrate decreased with time, with no significant difference among the groups (p > 0.05). The number of young fibroblasts was elevated in all groups evaluated at 7 days. The experimental group showed the highest number of cells at all time intervals, but the difference with the sealer group at 7 (p = 0.001) and 15 days (p = 0.002) and the control group at 30 days was not significant (p = 0.001). Regarding tissue repair events, the amount of collagen fibers increased over the experimental intervals, with no significant difference between the sealer and control groups (p > 0.05). CONCLUSION: The experimental RCFS based on calcium and strontium aluminates proved to be biocompatible for use in close contact with periapical tissue, inducing a low inflammatory reaction and favoring rapid tissue repair.

Influence of chlorhexidine digluconate on biocompatibility of cements: Morphological and immunohistochemistry analysis.

In this study, the in vivo biocompatibility was evaluated by using conventional ionomer cements modified with Chlorhexidine (CHX) in different time intervals. In total, 105 male Wistar rats were randomized into seven groups: control, groups M, M10, M18 and groups RL, RL10, RL18 (M-Meron and RL-RivaLuting, and added CHX-10% and CHX-18%, respectively). Histological analyses of inflammatory infiltrate and collagen fibers, and immunohistochemistry of CD68+ for macrophages (MOs) and multinucleated giant cells (MGCs) were performed. Data were analyzed using the Kruskal-Wallis and Dunn (p < .05) tests. Intense inflammatory infiltrate was demonstrated in Group Riva CHX-18% within 7 and 15 days (p < .05), without differences after 30 days. For collagenization, healing of the groups was compatible with that of control in 15 and 30 days (p > .05). Immunomarking of CD68+ was more significant in the groups with higher concentration of CHX. There was significant difference in quantity of MGCs in groups with 18% CHX, Meron (p = .001) in 7 days, and in Riva at 30 days (p = .001). Significant difference was also found in quantities of MOs in Groups Meron and Riva in 7 days (p = .001), and only in Riva at 15 and 30 days (p = .001). The cements with addition of CHX demonstrated biocompatibility with tissues. Riva CHX-18% had the most effect on cells of the inflammatory process but showed satisfactory tissue repair. RESEARCH HIGHLIGHTS: The concentration of 18% chlorhexidine was shown to be biocompatible with tissues; the slow release of chlorhexidine by the cements could significantly prolong its antibacterial effect on the oral medium.

Which self-etch acidic composition may result in higher dental bonds at the long-term? A network meta-analysis review of in vitro studies.

OBJECTIVES: This review evaluated the effects of the acidic composition of self-etch (SE) adhesives at the long-term bond strengths to dentin and enamel. DATA: The review followed the PRISMA Extension Statement for network meta-analysis. Studies were identified by a systematic search in PubMed, Web of Science, and Scopus databases. STUDY SELECTION: The inclusion criteria were in vitro studies that evaluated bond strength data of samples analyzed at both immediate and long-term (after aging simulation) periods and that were bonded to sound dentin/enamel using SE adhesives, with at least one group of adhesives being based on 10-MDP (10-methacryloyloxy-decyl-dihydrogen-phosphate; control) and the other group being comprised of alternative acidic monomers. Statistical analyses were conducted using two methods: standard pairwise meta-analysis (SPMA) and Bayesian network meta-analysis (NMA). Heterogeneity was assessed by using the Cochran Q test and I2 statistics. RESULTS: From 5220 studies identified, 87 met the eligibility criteria and 83 were meta-analyzed. Seventeen adhesives were based on 10-MDP and 44 systems were based on alternative acids. The resin-dentin/enamel bonds were predominantly reduced after aging (∼84% of cases). From the SPMA findings, the following acidic compositions showed lower bond strength values (effect size: mean difference [MD] with 95% confidence interval [95% CI]) than 10-MDP: 4-META (MD -4.99, 95% CI: -7.21, -2.78; p<0.001); sulfonic acids (MD -9.59, 95% CI -12.19, -6.98; p<0.001); unspecified phosphate esters (MD -8.89, 95% CI -17.50, -0.28; p = 0.04); or mixed acids (MD -11.0, 95% CI -13.62, -8.38; p<0.001). The dental bonds were benefited from the presence of 10-MDP upon longer aging (>6 months). From the NMA probabilistic findings, adhesives based on 10-MDP and phosphonic acids ranked as having the best and the worst bonding potential to dentin, respectively. More than one composition (phosphonic acids and mixed acids) ranked similarly to 10-MDP in enamel. The studies scored as having moderate risk of bias (58.6%), followed by low (39.1%) and high (2.3%) risk of bias. CONCLUSION: 10-MDP is an outstanding acidic monomer that contributes to higher bonds to dentin at the long-term. In enamel, there is no evidence that one acidic composition prevails over the other. CLINICAL SIGNIFICANCE: The acidic composition of SE adhesives affects the resistance of dental bonds after simulated aging, with 10-MDP playing a significant role in the adhesion to dentin but not to the enamel. REGISTRATION NUMBER: This report is registered at the Open Science Framework (osf.io/urtdf).

Antimicrobial properties, mechanics, and fluoride release of ionomeric cements modified by red propolis.

OBJECTIVES: To evaluate the antimicrobial activity, mechanical properties, and fluoride release capacity of glass ionomer cement (GIC) used for cementing orthodontic bands and modified by ethanolic extract of red propolis (EERP) in different concentrations. MATERIALS AND METHODS: Two orthodontic GICs containing EERP at 10%, 25%, and 50%, were used. The following assays were carried out: cell viability tests against Streptococcus mutans and Candida albicans, diametral tensile strength, compressive strength, shear bond strength, microhardness, and fluoride release capacity. The statistical analyses of the antimicrobial tests, fluoride release, diametral tensile strength, compressive strength, and microhardness were performed using two-way analysis of variance and Tukey test (P < .05). Shear bond strength data were analyzed using one-way analysis of variance followed by Tukey test (P < .05). RESULTS: At the concentrations of 25% and 50%, EERP was shown to be a promising antimicrobial agent incorporated into GICs against C albicans (P < .001) and S mutans (P < .001). The fluoride release capacity of the GICs was not affected, and the EERP concentration of 25% was the one that least affected the mechanical properties of the cements (P > .05). CONCLUSIONS: The GICs containing EERP at 25% showed a significant increase in their antimicrobial activity against S mutans and C albicans, while mechanical properties and fluoride release remained without significant changes.

Analysis of Chlorhexidine Modified Cement in Orthodontic Patients: A Double-Blinded, Randomized, Controlled Trial.

OBJECTIVES: The aim of this study was to evaluate the microbiological and mechanical properties of glass ionomer cement (GIC) modified by chlorhexidine (CLX) for the purpose of cementing bands to the teeth of orthodontic patients. MATERIALS AND METHODS: Ten patients, between the ages of 19 and 33 years, in the initial stage of orthodontic treatment, were randomly designated to two groups using the split-mouth design (n = 10). One group (GICEX) had bands cemented with GIC modified by CLX and a Control group (GIC), evaluated at time intervals before (T0), 3 months (T3), and 6 months (T6) after cementation. Total microbiological counts were performed, and color stability of tooth enamel, salivary pH, and the adhesive remnant index (ARI) were evaluated. STATISTICAL ANALYSIS: The Friedman and Dunn's tests, Mann-Whitney, one-way analysis of variance, and Tukey, and paired and non-paired t-tests (p< 0.05) were used. RESULTS: In T3, there was evidence of significant reduction in the quantity of colony forming unit (CFU) in GICEX group in comparison with the Control (p = 0.041). In T6, the quantity of CFU was similar to the quantity in T3 and significantly different to control (p = 0.045); Control group demonstrated a similar quantity of CFU between the experimental time intervals (p = 0.066). Salivary pH demonstrated significant difference only between the time intervals T0 and T6 (p = 0.022). The tooth enamel color (p = 0.366) and ARI (p = 0.343) values demonstrated no significant changes. CONCLUSION: The incorporation of CLX into GIC demonstrated effective antibacterial action, allowed a good bond of the cement to the enamel, a high rate of survival of the bands, did not change the color of the tooth enamel, and maintained the salivary pH at physiological levels.

Effectiveness of Secondary Alveolar Bone Graft on Canine Eruption: Systematic Review.

There are controversies related to the effects of bone grafts on tooth eruption and impaction in patients with cleft lip and palate. The aim of this systematic review was to evaluate the effectiveness of bone grafting on eruption of canines in patients with unilateral cleft lip and palate (UCLP). An electronic search was conducted in six electronic databases and gray literature, without limitations on year of publication or language. The primary outcome was the increase in rate of canine eruption; the secondary outcomes were success of the bone graft, canine impaction due to agenesis of the lateral incisor, and effect of orthodontic treatment before and after bone grafting. The risk of bias was analyzed by means of the tool Cochrane risk of bias in nonrandomized controlled trials (NRCTs) of interventions (ROBINS-I). The certainty of the evidence was assessed for outcomes reported through a narrative synthesis using grading of recommendations, assessment, development and evaluation (GRADE) approach. Four NRCTs were included, with a total of 360 patients, 283 UCLP and 77 bilateral cleft lip and palate (BCLP). The studies reported association between the increase in the rate of tooth eruption and bone graft with very low certainty of evidence, and greater experience of surgical success, with low certainty of evidence. The majority of the studies found an association between increase in the rate of canine impaction and agenesis of the lateral incisor, with very low certainty of evidence. There was very low certainty of the efficacy of secondary alveolar bone grafting for increasing the rates of eruption and reducing impaction of the maxillary canine.

Biocompatibility of Ionomeric Cements Modified by Red Propolis: A Morphological and Immunohistochemical Analysis.

PURPOSE: To evaluate the biocompatibility in rat subcutaneous tissue of conventional orthodontic cements, Riva (R) and Meron (M), modified by the addition of ethanolic extract of red propolis (EERP), at different concentrations and time intervals. MATERIALS AND METHODS: One hundred eight male adult Wistar rats were used, distributed in nine groups of cements with added EERP at the concentrations used (C-control, MC, M10, M25, M50, RC, R10, R25, and R50). The rats were sacrificed after 3 time intervals (7, 15, and 30 days). Histological and immunohistochemical analyses were performed. The findings were statistically analyzed using the Kruskal-Wallis test followed by Dunn's test (p < 0.05). RESULTS: The highest concentrations led to a higher level of inflammation at the initial times (p < 0.05), but without differences after 30 days. In terms of collagen, there was less collagenization at the initial times in comparison with the control group C. However, over time, the addition of propolis resulted in healing compatible with that of group C. The level of CD68 immunostaining was statistically significantly higher in the groups with the highest concentrations (R50 and M50) (p = 0.001). CONCLUSION: Orthodontic cements with the addition of EERP were found to be biocompatible in rat subcutaneous tissue. Riva cement with the addition of 50% EERP showed the highest tissue inflammation, but with satisfactory tissue repair.

Effect of Orthodontic Treatment on Tooth Autotransplantation: Systematic Review of Controlled Clinical Trials.

This systematic review was focused on evaluating tooth autotransplantation, considering its impacts on the teeth, bone, soft tissues, and aesthetics in orthodontic patients. A bibliographic search was conducted without limitations on year of publication or language in the databases of PubMed, Web of Science, Scopus, Medline Complete, Cochrane, Clinical Trials, and Trials Central. For triage of articles, indications, surgical planning, orthodontic movement, risk factors for treatment, and long-term follow-ups were considered. For outcomes, the results with reference to teeth, alveolar bone, periodontal tissues, and esthetic satisfaction were considered. Risk of bias was evaluated using the methodological index for nonrandomized studies-MINORS. The results showed 10 controlled clinical trials, and no randomized clinical trials were found. The selected studies included 715 patients and 934 autotransplanted teeth among which there were premolars, molars, and anterior teeth evaluated in the long term, indicating that orthodontics associated with autotransplantation indicated a result that was generally clinically acceptable. The quality of the set of evidence was considered medium due to the presence of different methodological problems, risk of bias, and significant heterogeneity in the evaluated studies. There was a sufficient body of evidence that justified autotransplantation in patients who needed orthodontic movement. In teeth, there was an increase in root resorption influenced by orthodontics, but without impacting on the general clinical result in the long term. Bone and periodontal tissue do not appear to be affected by orthodontics. The patient's aesthetic satisfaction was not considered in the studies.

Histological analysis of biocompatibility of different surgical adhesives in subcutaneous tissue.

The focus of this study was to test the hypothesis that there would be no difference between the biocompatibility of cyanoacrylate-based adhesives in rat subcutaneous tissues. In total, 60 male Wistar rats were used, and divided into four groups (n = 15): Group C (control, PVA-polyvinyl alcohol sponge), Group NO (N-butyl-2-octylcyanoacrylate), Group NH (n-hexyl-cyanoacrylate), and Group EC (Ethyl-cyanoacrylate). The animals were sacrificed after time intervals of 7, 15, and 30 days and tissues were analyzed under optical microscope as regards the events of inflammatory infiltrate, edema, necrosis, granulation tissue, giant cells, young fibroblasts, and collagen formation. The results were statistically analyzed by the Kruskal-Wallis and Dunn tests (p < .05). Significant inflammatory infiltrate was shown for all the adhesives in the time intervals of 7 (p = .004) and 15 days (p = .003). In the time interval of 30 days, moderate inflammatory infiltrate was observed in Groups NH and EC, with significant difference from Control (p = .001). The quantity of collagen fibers in all the experimental groups showed significant difference compared with Control in the time intervals of 7 (p = .002) and 15 days (p = .001), at 30 days only Group EC showed a smaller quantity of collagen fibers in comparison with Control (p = .001). The hypothesis was rejected. The adhesive N-butyl-2-octylcyanoacrylate had less influence on the inflammatory intensity of multinucleated giant cells. Ethyl-cyanoacrylate demonstrated the lowest level of biocompatibility among the adhesives, but its use in clinical practice may be promising for coaptation of smaller edges of superficial tissue. Surgical adhesives were shown to be feasible for clinical use in substitution of conventional suturing. Ethyl-cyanoacrylate should be used with caution due to its greater influence on tissues.

Morphological and immunohistochemical analysis of the biocompatibility of resin-modified cements.

The aim of this double-blind randomized study was to evaluate the biocompatibility of resin-modified glass ionomer cements (RMGIC) by means of morphological and immunohistochemical analyses. RMGICs were selected and divided into four groups: Group CK (Crosslink Orthodontic Band Cement); Group RS (Resilience Light Cure Band Cement) Group RMO (RMO Band Cement), Group TP (Transbond Plus Light Cure Band), and Group C (Control-polyethylene). The materials were implanted in rat subcutaneous tissues, randomly selected for this study. After time intervals of 7, 15, and 30 days the tissues were submitted to morphological analysis. In immunohistochemical analysis, the immuno-marking of antibody CD68 was evaluated. The results obtained were statistically analyzed by the Kruskal-Wallis and Dunn tests (p < .05). In the morphological analysis after 7 days, Groups RS, RMO and TP showed more intense inflammatory infiltrate (p = .004) and only Group RMO presented greater intensity of multinucleated giant cells (p = .027). In the immunohistochemical analysis, Groups RMO and RS were observed to present a larger quantity of CD68+ (p = .004) in the time interval of 7 days and only Group RMO presented statistically significant difference for this parameter after 15 days (p = .026). In the time interval of 30 days, Group RMO presented the largest quantity of multinucleated giant cells (p < .004). The RMGICS Crosslink and Transbond Plus provided significantly better tissue biocompatibility than the Resilience and RMO Cements.

Optimizing Esthetics and Function in a Case of Moderate Reduced Bone Support.

The aim of this article is to report the orthodontic treatment of a woman aged 53 years 6 months whose chief complaint involved her facial esthetics and crowding. She presented a moderate reduction in bone support, but no periodontal disease, over the past 15 years. The maxillary left first premolar and both mandibular first premolars were extracted. The dental protrusion was reduced and all the spaces were closed, resulting in a significant improvement in facial esthetics. After 16 months, the satisfactory results in terms of the functional position of the teeth were maintained with the bone level remaining unchanged.

Thickness and nanomechanical properties of protective layer formed by TiF4 varnish on enamel after erosion.

The layer formed by fluoride compounds on tooth surface is important to protect the underlying enamel from erosion. However, there is no investigation into the properties of protective layer formed by NaF and TiF4 varnishes on eroded enamel. This study aimed to evaluate the thickness, topography, nanohardness, and elastic modulus of the protective layer formed by NaF and TiF4 varnishes on enamel after erosion using nanoindentation and atomic force microscopy (AFM). Human enamel specimens were sorted into control, NaF, and TiF4 varnish groups (n = 10). The initial nanohardness and elastic modulus values were obtained and varnishes were applied to the enamel and submitted to erosive challenge (10 cycles: 5 s cola drink/5 s artificial saliva). Thereafter, nanohardness and elastic modulus were measured. Both topography and thickness were evaluated by AFM. The data were subjected to ANOVA, Tukey's test and Student's t test (α = 0.05). After erosion, TiF4 showed a thicker protective layer compared to the NaF group and nanohardness and elastic modulus values were significantly lower than those of the control group. It was not possible to measure nanohardness and elastic modulus in the NaF group due to the thin protective layer formed. AFM showed globular deposits, which completely covered the eroded surface in the TiF4 group. After erosive challenge, the protective layer formed by TiF4 varnish showed significant properties and it was thicker than the layer formed by NaF varnish.

Effect of degree of conversion on in vivo biocompatibility of flowable resin used for bioprotection of mini-implants.

OBJECTIVE: To test the hypothesis that there is no difference between the biocompatibility and degree of monomer conversion of flowable resins used as bioprotective materials of orthodontic mini-implants. MATERIALS AND METHODS: Forty-eight male Wistar rats were divided into four groups (n  =  12). Group Control (polyethylene), Group Wave, Group Top Comfort, and Group Filtek. The animals were sacrificed after time intervals of 7, 15, and 30 days and tissues were analyzed under optical microscopy for inflammatory infiltrate, edema, necrosis, granulation tissue, multinucleated giant cells, and collagen formation. The degree of conversion was evaluated by the Fourier method. Biocompatibility and degree of conversion were evaluated by the Kruskal-Wallis and Dunn tests, and analysis of variance and the Tukey test, respectively (P < .05). RESULTS: An intense inflammatory infiltrate was observed on the seventh day, with Groups Top Comfort and Filtek differing statistically from Group Control (P  =  .016). Edema, necrosis, granulation tissue, and giant cells showed greater expressiveness at 7 days, without statistical difference between them (P > .05). For the presence of collagen fibers, Group Top Comfort was shown to differ statistically from Group Control (P  =  .037) at 15 days and from Groups Filtek and Control (P  =  .008) at 30 days. Monomer conversion ranged from 62.3% in Group Top Comfort at 7 days to 79.1% in Group Filtek at 30 days. CONCLUSIONS: The hypothesis was rejected. The resin Top Comfort demonstrated lower tissue repair capacity with a lower number of collagen fibers compared with Filtek and Wave resins. The resin Top Comfort showed the lowest conversion values during the experiment.

Effect of hydrochloric acid commercial presentation for microabrasion technique on loss of enamel structure and surface / Efeito da apresentação comercial de ácido clorídrico para técnica de microabrasão na perda de estrutura e superfície do esmalte

Introdução: A técnica de microabrasão pode ser realizada através de pasta pronta para uso, disponível comercialmente, ou o profissional pode manipulá-la no consultório. Objetivo: Verificar o efeito da apresentação comercial do ácido clorídrico a 10% na manipulação de pasta para microabrasão sobre a superfície do esmalte. Metodologia: Foram selecionados incisivos bovinos e divididos em dois grupos, de acordo com a apresentação comercial do ácido clorídrico (líquido ou em gel). O tratamento foi realizado através de dez aplicações com 10s de duração cada, intercaladas por lavagem de 10s. Vinte incisivos (n=10) foram utilizados para se determinar a perda de estrutura do esmalte. Cada amostra foi pesada, em balança analítica, antes e após submissão à microabrasão. Outras 20 amostras (n=10) foram utilizadas para determinação da rugosidade superficial média (Ra) utilizando-se um rugosímetro. Três amostras de cada grupo do experimento anterior foram selecionadas, aleatoriamente, e outras três amostras adicionais foram preparadas como controle (baseline) para análise em MEV. Resultados: Verificou-se diferença estatística significativa entre a massa final e a inicial e rugosidade superficial das amostras, independente da apresentação comercial do ácido. Nas imagens de MEV observou-se presença de superfície regular para o grupo controle (baseline). Nas demais imagens verificou-se superfície com considerável irregularidade e dissolução discreta do esmalte. Conclusões: O tratamento realizado causou perda significativa de estrutura e aumentou a rugosidade superficial dos espécimes, independente da apresentação comercial do ácido e sem apresentar diferença entre os grupos ao final. A apresentação comercial do ácido não parece ser um fator a interferir no tratamento. (AU)

Introduction: The microabrasion technique can be performed using a commercially available paste, or the dentist can prepare it in his office. Objective: To verify the effect of hydrochloric acid commercial presentation in the handling of microabrasion paste on the enamel surface. Methodology: Bovine incisors were divided into two groups, according to the commercial presentation of 10% hydrochloric acid (liquid or gel). The treatment was carried out through ten applications of 10 s duration each, intercalated with a 10s wash. Twenty teeth (n=10) were used to determine the loss of enamel structure. Each sample was weighed on an analytical balance before and after submission to microabrasion. Another 20 teeth (n=10) were used to determine the average surface roughness (Ra) using a rugosimeter. Three samples from each group of the previous experiment were selected, randomly, and another three additional samples were repared as a control (baseline) for SEM analysis. Results: There was a statistically significant difference between the final and initial mass and the surface roughness of the samples, regardless of the acid commercial presentation. In the SEM images, a regular surface was observed for the control group (baseline). In the other images, there was a surface with considerable irregularity and a slight dissolution of the enamel. Conclusions: The treatment carried out. (AU)