Acta odontologica latinoamericana : AOL最新文献

Dental pulp and periodontium have different communication routes including, e.g., apical foramen, accessory canals and dentin tubules. Scaling, planing and root surface treatment with ethylenediaminetetraacetic acid (EDTA)-based conditioner are used in regenerative periodontal procedures. Such treatment may generate pathological communication between the two structures due to interruption of the vascular pedicle or migration of bacteria and/or inflammatory byproducts from deep periodontal pockets, which may generate pulp pathology.

Aim: The aim of this study was to evaluate the influence of minimally invasive periodontal regenerative surgery on pulp vitality status in single-rooted and multi-rooted teeth associated to infraosseous defects extending to the middle and apical thirds.

Materials and method: This was a retrospective study on 30 teeth from 14 patients who received care between August 2018 and August 2019 at the postgraduate Department of Specialization in Periodontics of the Buenos Aires University School ofDentistry (FOUBA). Clinical and radiographic endodontic diagnosis was performed 6 months after the minimally invasive regenerative periodontal treatment.

Results: Only two out of the 30 teeth presented changes in pulp status following regenerative periodontal procedure: irreversible pulpitis at 30 days and pulp necrosis at 180 days post-treatment. The rate for risk of change in pulp vitality status was 6.7%. Teeth with grade I and II furcation lesions (n=9) presented no change in pulp status.

Conclusions: Regenerative periodontal surgery had no significant influence on pulp status in single-rooted and multi-rooted teeth with infraosseous defects extending to the level of the middle and apical third.

During ceramic veneer luting, resin cement polymerization is performed with interposition of the dental ceramic.

Aim: To evaluate how and how much the photoactivation time affects the Vickers hardness of resin-based cements with interposed ceramic.

Materials and method: A total 24 specimens H mm in diameter and 1 mm thick were made from Paracore White Coltene (PC), Densell Resin Duo Cement (DC), 3MRelyX Veneer (RX) and Coltene Fill Up! (FU), interposing VitablockMarkII (Vita Zahnfabrik) feldspathic ceramic 0.6 mm thick during photoactivation. The materials were polymerized using 100% and 25% of the times indicated by the manufacturers with a Coltolux LED ((Coltene) light with intensity 1200 mW/cm². Each polymerization time group consisted of three specimens of each material, which were stored dry in darkness at 37 °C for 7 days. Three Vickers microhardness measurements were made on the top and bottom surfaces of each specimen using a Vickers Future Tech FM300 microhardness tester (300 g, 5 s). The values were averaged, and the bottom/top ratios calculated. Results were analyzed by ANOVA. (p<0.05) complemented with multiple comparisons using Tukey's test (p<0.05).

Results: Different photoactivation times were found to have a significant effect on hardness values of the cements evaluated, with significant differences between some of the cements. No statistically significant difference was found for the effect of photoactivation time on bottom/top microhardness ratio in those materials.

Conclusions: Under the experimental conditions employed, it can be concluded that photopolymerization for shorter times and the interposition of restorative material significantly affectpolymerization quality as evaluated by microhardness, but the bottom/top ratio was unaffected by differences in polymerization time.

Aggressive periodontitis (AP) is the most serious entity of periodontal disease (stage III/IV, grade C periodontitis according to the latest classification, 2017).

Aim: to enhance knowledge of periodontal microbiota in AP in native Argentine patients and describe the effect of a combined pharmacologicalmechanical periodontal treatment on clinical and microbiological parameters.

Materials and method: The study analyzed 42 periodontal sites in 11 patients diagnosed with AP. Clinical periodontal parameters were recorded at baseline, 45, 90 and 180 days. Microbiological samples were taken before treatment and at 180 days. PCR was used to determine presence of the periodontopathic bacteria Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Treponema denticola (Td), Prevotella intermedia (Pi) and Fusobacterium nucleatum (Fn). Patients underwent periodontal therapy including antibiotics (Amoxicillin 500mg + Metronidazole 250mg; 8hs/7 days), and were reevaluated at 45, 90 and 180 days.

Results: Mean age was 28.4 ± 7.9 years. The initial PCR detected the following frequencies: Aa 14.3%, Pi 61.9%, Pg 71.4%, Tf 81.0%, Fn 95.2% and Td 97.6%. Baseline microbiological samples revealed significantly higher prevalence of Pg over Aa (p=0.012). Clinical parameters improved significantly after treatment (73.8% PS<5 mm; PS, NIC, SS p<0.001). At 180 days, a significant decrease in microbiological detection rates was observed (Fn, Td, Tf, Pi, Aa p<0.05). Aa was no longer detectable while Pg did not decrease significantly (p=0.052). Fn was the only study species detected in 100% (n=11:42) of residual pockets (PS≥5 mm) (p=0.053).

Conclusion: In the initial samples, there was significant prevalence of Pg over Aa. Significant clinical improvement was achieved after the mechanical-pharmacological treatment, with undetectable levels of Aa, while Fn persisted in residual pockets, and Pg was present at most of the treated sites.

Third molar extraction surgery is a frequentprocedure in dentistry. Like any surgical procedure, it may lead to inflammatory responses, and postoperative pain is one of its main complications. Furthermore, temporomandibular disorder (TMD) is a collective termfor several clinicalproblems involving orofacial structures. Patients withparafunction are more sensitive to mechanical stimuli such as pressure during surgical procedures.

Aim: To analyze postoperative pain in patients with and without bruxism subjected to third molar extraction surgery.

Materials and method: This was an observational study including four groups with a 1:1:1:! allocation ratio, conducted following ethical approval. Patients classified as ASA I with an indication for lower third molar extraction were recruited. Bruxism was self-reported. Two surgical techniques were used: one with only forceps and levers (ST1) and another with osteotomy and odontosection (ST2).

Results: Four groups (bruxism and surgical techniques) were enrolled, each with a convenience sample (n=34). Postoperative pain levels were higher in patients with than without bruxism (p<0.05). The comparison between surgical techniques showed significantly higher pain levels only on the seventh day for ST2 groups (p<0.05). Oral mucosaflap incisions did not cause significantly higher persistence and pain levels.

Conclusions: Bruxism, osteotomy, and odontosection may have increased postoperative pain levels, whereas performing an oral mucosa flap did not cause significant differences. Nevertheless, these preliminary data should be interpreted carefully. Randomized controlled trials are required to reinforce the findings of this study.

Color stability is among the most frequent causes of restoration failures, and influences surface properties.

Aim: The aim of this study was to investigate the influence of pigment solutions on low-shrinkage and conventional composites regarding changes in the physical properties of composite surfaces.

Materials and method: Specimens of four composites (Filtek Z350 XT, Point 4, N'Durance and Venus Diamond) were randomly distributed into three groups to be submitted to each of three pigment solutions (red wine, tomato sauce and coffee) in fifteen-minute daily cycles, for twenty-eight days. There were 12 groups altogether (n = 10). Color, surface roughness and hardness tests were performed. Statistical analysis includedAnalysis of variance (ANOVA) and Tukey's significance test (a = 0.05).

Results: Color changes caused by the solutions did not differ significantly among Filtek Z350 XT, Venus Diamond and N'Durance. Hardness decreased significantly in Filtek Z350 XT and Venus Diamond after chemical challenge with each solution. For the composite independent factor, roughness was highest in Venus Diamond, followed by Filtek Z350 XT, Point 4 and N'Durance.

Conclusions: Treatment with different pigment solutions (red wine, tomato sauce or coffee) increased stainability and decreased hardness of both low-shrinkage and conventional composites, while roughness was unaffected.

After ozone therapy for bleaching, it is important to evaluate enamel surface properties, to ensure thatbleaching provides adequate conditions for sound dental substrate. Aim: The aim of this in vitro studywas to evaluate the effects of a bleaching treatment with 10% carbamide peroxide (CP), with or withoutozone (O), on the microhardness, roughness and micromorphology of the enamel surface.

Materials and method: Bovine enamel blocks were planed and distributed among the following three bleachingtreatment groups (n=10): CP - 1 hour per day/14 days (Opalescence PF 10%/ Ultradent); O - 1 hourper day every 3 days/3 sessions (Medplus V Philozon, 60 mcg/mL and oxygen flow rate of 1 L/min);and OCP - CP with O, 1 hour per day every 3 days/3 sessions. Enamel surface microhardness (Knoop),roughness (Ra), and micromorphology by scanning electron microscopy (5,000x magnification) weredetermined before and after the treatments.

Results: ANOVA and Tukey-Kramer’s test showed thatenamel microhardness remained unchanged by treatment with O and OCP (p=0.0087), but decreasedby treatment with CP. Treatment with O promoted higher enamel microhardness than the other groups(p=0.0169). Generalized linear mixed models for repeated measures over time indicated treatment withCP increased enamel roughness more than OCP or O (p=0.0003). CP produced slight irregularitiesin enamel micromorphology after the whitening treatment. O, with or without CP, maintained themechanical and physical properties of microhardness and enamel surface micromorphology, and eithermaintained or reduced surface roughness, compared to the conventional tray-delivered CP bleachingtreatment.

Conclusions: Treatment with 10% carbamide peroxide in trays promoted greater changesin enamel surface properties than treatments with ozone and with 10% ozonized carbamide peroxidein the office.

Oral mucositis (OM) is a frequent complication in cancer patients who are undergoing chemotherapyor radiotherapy. It manifests as an inflammation of the oral mucosa, sometimes provoking severeconsequences such as eating limitations, difficulty in speaking, and possibly superinfection.

Aim: The aim of this review was to update the evidence published during the last five years on the treatment oforal mucositis induced by radiotherapy and/or chemotherapy in patients with cancer.

Materials and method: A search was conducted in Pubmed, Scielo and Scopus, using the search terms mucositis,stomatitis, therapy, treatment, oral cancer, oral squamous cell carcinoma, head and neck cancer andhead and neck carcinoma, with Mesh terms and free terms, from 2017 to January 2023. The systematicreview was conducted in accordance with the PRISMA guidelines.

Results: A total 287 articles wereretrieved, of which 86 were selected by title and abstract, and 18 were included after full-text analysis.The most frequently assessed variables were OM severity, pain intensity and healing time. Treatmenttypes were diverse, and included drugs, mouthwashes, medicines based on plant extracts, cryotherapyand low-intensity laser therapies.

Conclusion: Dentoxol mouthwashes, Plantago major extract, thymehoney extract, zinc oxide paste, vitamin B complex combined with GeneTime, and the consumption ofL-glutamine are effective in diminishing the severity of OM. Pain intensity was lower with doxepinmouthwashes and diphenhydramine-lidocaine-antacid mouthwashes.

Albumin is a salivary enzyme capable of cleaving ester linkages and catalyzing degradation of resin-based dental materials. However, the effect of concentration-dependent esterolytic action on composite resins as yet remains unexplored.

Aim: The purpose of this study was to evaluate whether artificial saliva formulations with different concentrations of albumin affected the surface roughness, flexural strength and microhardness of a composite resin.

Materials and method: Specimens (25x2x2mm) of a nanofilled composite (Filtek Z350XT, 3M/ESPE) were prepared and analyzed for average surface roughness (Ra/pm). The specimens were then allocated to 6 groups (n=30), to be treated with different salivary albumin concentrations: 0, 10, 50, 100, 200, 400 pg/mL. The specimens were stored in their respective artificial saliva groups, half of them for 24 h and the remainder for 180 days (artificial saliva renewed weekly), after which they were submitted to a new Ra reading, and tested for three-point flexural strength (FS, MPa). The specimens stored for 180 days were analyzed for Knoop microhardness (KH, Kg/mm²). Data were submitted to two-way ANOVA (Ra and FS) and one-way ANOVA (KH).

Results: Although Ra increased (p < 0.001) and FS decreased (p < 0.001) from 24 hours to 180 days of storage, the albumin concentration did not significantly affectRa (p = 0.168), FS (p = 0.477) or KH (p = 0.378).

Conclusion: The esterolytic action of albumin did not increase the artificial-saliva-induced hydrolytic degradation of the composite resin.

Dentin hypersensitivity (DH) is characterized by rapid, acute pain arising from exposed dental tubules.

Aim: the aim of this study was to evaluate the roughness, tubule occlusion, and permeability of eroded dentin brushed with different toothpastes.

Materials and method: ninety bovine teeth were cut into blocks. Thirty hemifaces were protected with varnish and the other sixty were submitted to permeability tests. Specimens were divided into groups according to the dentifrices: without fluoride (WF), sodium fluoride (NaF), and stannous fluoride (SnF2). The blocks were subjected to a 5-day erosive-abrasive protocol. Surface roughness and dentinal tubule occlusion (n=10) were assessed for both control and test hemifaces of the same sample along with permeability analysis (n=20). Two-way RM ANOVA and Tukey's post-hoc test were performed (p≤0.05).

Results: NaF and SnF2 presented higher roughness than WF. The number of open tubules was higher in WF. Permeability was higher in SnF2, but there was no significant difference between WF and NaF.

Conclusions: both fluoride toothpastes occluded dentinal tubules and increased roughness. NaF toothpaste promoted greater decrease in dentin permeability.

Aim: This study evaluated the influence of chitosan added to a universal adhesive system used in totaletch (TE) or self-etch (SE) mode on dentin permeability, and on the micromorphology of the adhesive layer.

Materials and method: Dentin discs were obtained from human third molars and randomly distributed according to bonding strategy (TE or SE), and to whether or not 1% chitosan (C) was added to a universal adhesive system (Single Bond Universal/3M ESPE), to create the following groups (n=10): TE, TEC, SE, and SEC. Dentin permeability was measured at baseline and after application of dentin treatments. The surface of the adhesive layer (AL) and the dentin adjacent to the AL were examined under a scanning electron microscope.

Results: There were no significant differences in permeability percentage between the groups with and without C (TE and SE versus TEC and SEC) (p>0.05; Mann Whitney test). Dentin permeability was lower when the adhesive system was applied in the SE mode, regardless of the addition of C. The micromorphology of the AL surface showed irregularities, and a greater degree of porosity, when the adhesive system was applied in the SE mode, regardless of chitosan addition. There was a greater depth of penetration of the adhesives into the dentin adjacent to the AL in both the TE and TEC groups. Chitosan added to the adhesive system did not influence dentin permeability.

Conclusions: The self-etch strategy led to lower dentin permeability, and to more irregularities on the surface of the adhesive layer.