Byrsonima sericea Ethanol Extract Protected PC12 Cells from the Oxidative Stress and Apoptosis Induced by 6-Hydroxydopamine.

Parkinson's disease is characterized by the progressive loss of dopaminergic neurons in the nigrostriatal pathway and oxidative stress is one of the main mechanisms that lead to neuronal death in this disease. Previous studies have shown antioxidant activity from the leaves of Byrsonima sericea, a plant of the Malpighiaceae family. This study aimed to evaluate the cytoprotective activity of the B. sericea ethanolic extract (BSEE) against the cytotoxicity induced by 6-hydroxydopamine (6-OHDA) in PC12 cells, an in vitro model of parkinsonism. The identification of phenolic compounds in the extract by HPLC-DAD revealed the presence of geraniin, rutin, isoquercetin, kaempferol 3-O-ß-rutinoside, and quercetin. The BSEE (75-300 µg/mL) protected PC12 cells from toxicity induced by 6-OHDA (25 µg/mL), protected cell membrane integrity and showed antioxidant activity. BSEE was able to decrease nitrite levels, glutathione depletion, and protect cells from 6-OHDA-induced apoptosis. Thus, we suggest that the BSEE can be explored as a possible cytoprotective agent for Parkinson's disease due to its high antioxidant capacity and anti-apoptotic action.

Influence of ceramic crown design (translucent monolithic zirconia vs. bilayered) of implant-supported single crowns after mechanical cycling.

OBJECTIVES: This study aimed to assess the influence of translucent monolithic versus bilayered crowns and whether the use of a CoCr base abutments affects the fatigue and fracture resistance of screwed implant-supported single crowns with external connections under mechanical cycling. MATERIALS AND METHODS: Fifty specimens were divided into groups: (1) metal-ceramic (MC) crown, (2) veneered zirconia crown (Zr), (3) veneered zirconia crown with a CoCr base abutment (ZrB), (4) monolithic translucent zirconia crown (MZr), and (5) monolithic translucent zirconia crown with a CoCr base abutment (MZrB). Specimens underwent mechanical cycling (5 × 106 cycles; 150 N) evaluating fatigue resistance (number of failures) and those that failed were subsequently subjected to fractographic analyses (stereomicroscope and scanning electron microscope) to evaluate failure location and area, and maximum fracture load was also measured. RESULTS: The failure-related survival rate (100%) and maximum fracture resistance of the MZrB were significantly higher than those of MC and Zr (50%; p < 0.05). There were no significant differences in the failure rate and fracture resistance when a CoCr base abutment was used or not in the translucent monolithic Zr groups (p > 0.05;MZrB vs. MZr). Failure location, with MC crowns' fractures, noted at the screw area (p = 0.043), while all-ceramic crowns were mostly in the cuspid and to failure area, the Zr group had the largest mean (15.55 ± 9.17 mm2) among the groups, significant difference only when compared with MC (1.62 ± 0.81 mm2) (p = 0.025). CONCLUSIONS: Translucent monolithic zirconia crowns exhibited significantly higher fatigue and fracture resistance compared with conventional MC and bilayered crowns. CLINICAL SIGNIFICANCE: The appropriate choice of material and manufacturing technique is crucial for predicting the higher clinical performance of single crowns. Enhanced mechanical resistance in terms of fatigue and fracture resistance can be achieved by replacing MC and bilayered restorations with computer-aided design and computer-aided manufacturing monolithic zirconia.

On the role of syllable structure in atypical phonological development: Evidence from the acquisition of /l/ by Portuguese children.

The alveolar lateral is phonetically and phonologically complex. Previous studies have shown that /l/ is one of the last segments to be acquired by typically developing Portuguese children. However, little is known about how Portuguese children with atypical development acquire /l/. In this paper, we investigate the acquisition of /l/ by Portuguese children with protracted phonological development (DLD; SSD). We explore the effect of syllable structure and segmental properties in the acquisition of /l/ and describe mismatches used for target /l/, thus contributing empirical evidence to the ongoing discussion on differential diagnoses for children with primary phonological disorders. Our results show that the lateral is more problematic in SSD than in DLD, with the manner of articulation being more problematic than its place. A syllable-segment interface effect was attested. Mismatches showed a preference for [w, ɾ, ø]. The results are discussed considering their implications for clinical practice and the role of target phonetic and phonological properties in the /l/ acquisition path.

Musculoskeletal Pain, Mood, and Sports Injury in Wheelchair Power Soccer Players.

CONTEXT: Wheelchair Power Soccer (WPS) is the only team sport that allows the participation of people with severe physical disabilities who require the daily use of motorized wheelchairs. These individuals may live with chronic pain due to the characteristics of the disabilities and treatments, interfering with their health and limiting their participation in sports. OBJECTIVES: To investigate the prevalence of musculoskeletal pain and its relationship with mood in WPS players and to analyze the incidence of traumatic injuries during a championship. METHODS: A prospective, longitudinal study was carried out on 30 WPS athletes (93.33% male) with a mean (SD) (range) age of 22.37 (9.79) (47) years. Data collection was performed during a South American WPS Championship lasting 3 days, with: investigation of the presence of musculoskeletal pain and mood through a questionnaire; investigation of the occurrence of traumatic injuries through match observation; and confirmation of the occurrence of traumatic injuries through access to medical department records. RESULTS: About 30% (n = 9/30) of the sample presented some pain on the day of evaluation, with an intensity of 5.67 (3.35) (10) points on the visual analog scale. The most common regions of pain were the lower back (13.3%, n = 4/30), thoracic (10%; n = 3/30), and cervical (10%; n = 3/30) areas of the spine. A total of 46.7% (n = 14/30) reported pain in the month before data collection but of less intensity (2.56 [4] [10] points), the most common regions being the lower limbs (20%; n = 6/30) and cervical spine (20%; n = 6/30). Among the between-group comparisons (ie, participants with pain vs without pain), no relationship was observed between mood state and pain. No traumatic injuries were identified during the competition. CONCLUSION: The presence of musculoskeletal pain was common in WPS players, but it was not related to mood. As no traumatic injuries were observed during the championship, this modality seems to be safe for people with physical disabilities in general.

Maternal treatment with aripiprazole prevents the development of a valproic acid-induced autism-like phenotype in juvenile male mice.

Autism spectrum disorder (ASD) describes a heterogeneous group of neurodevelopmental conditions characterized by deficits in social communication and repetitive behaviors. Aripiprazole (APZ) is an atypical antipsychotic that can safeguard mice against autism-like behavior induced by valproic acid (VPA). In the present study, we examined the effects of maternal treatment with APZ (10 mg/kg) in juvenile mice prenatally exposed to VPA on neurodevelopmental behaviors, social interactions, communication, and working memory, as well as synaptophysin (SYP), synaptosomal-associated protein, 25 kDa (SNAP-25) and microtubule-associated protein 2 (MAP-2) expression in the medial prefrontal cortex (mPFC) and cell viability in the hippocampus. In addition, to evaluate possible APZ interference with the anticonvulsant properties of VPA on pentylenetetrazole (PTZ)-induced seizures were evaluated. Maternal treatment with APZ significantly prevented body weight loss, self-righting, eye-opening, social interactions, social communication, and working memory deficits in mice prenatally exposed to VPA. Additionally, the decrease in the SYP, SNAP-25, and MAP-2 expressions in the mPFC and cell death in the hippocampus was prevented by APZ. Furthermore, APZ (10 mg/kg) did not interfere with the anticonvulsant effect of VPA (15 mg/kg) in animals with PTZ-induced seizures. These findings indicate that maternal treatment with APZ in pregnant mice exposed to VPA protects animals against the ASD-like behavioral phenotype, and this effect may be related, at least in part, to synaptic plasticity and neuronal protection in the PFC and hippocampus. APZ may serve as an effective pharmacological therapeutic target against autistic behaviors in the VPA animal model of ASD, which should be further investigated to verify its clinical relevance.

Device trueness in passivity and misfit of CAD-CAM frameworks: Conventional versus printed casts.

STATEMENT OF PROBLEM: Obtaining a passive and well-adapted framework is challenging when intraoral scanning edentulous arches with multiple implants. The trueness of the printed casts is unclear. PURPOSE: The purpose of this clinical study was to evaluate the trueness of frameworks made from conventional and printed casts regarding clinical passivity and misfit. MATERIAL AND METHODS: Ten participants with complete mandibular fixed implant-supported interim prostheses retained by 4 implants were included. Each participant had a conventional impression and a digital scan made. The digital scan was made using an innovative device. Both conventional and digital casts were made, and the virtual images were used for milling the digital framework in cobalt chromium alloy. All frameworks were evaluated for passivity and marginal vertical misfit with the single screw test, with 4 attempts consisting of the tightened screw position, a test with all screws tightened, and an interspersed tightening test. The Kruskal-Wallis test was used to evaluate the trueness of the tested device for framework construction through the single screw test on vertical marginal misfit in the conventional and printed groups (α=.008). The Friedman test was used to assess the effect of test type (α=.05), and the Wilcoxon test was used to identify group-to-group differences (α=.017). RESULTS: The absence of space between the framework and the abutments and interferences during its placement, as well as good stability, were observed clinically. In laboratory analysis, greater framework misfits were observed in the printed group compared with the conventional group when the single screw test was applied. Comparing the 3 tests used, the greatest misfits were observed when the framework was screwed onto the printed cast. CONCLUSIONS: The innovative device tested for the intraoral scanning of multiple implants had clinically acceptable accuracy for the construction of passive and adapted frameworks. The conventional cast was more accurate than the printed cast, with lower misfit values, in all tests.

Prevalence of proximal contact loss between implant-supported prostheses and adjacent natural teeth: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Proximal contact loss between implant-supported prostheses and adjacent natural teeth is a complication that has been reported in clinical practice. However, the prevalence of the condition is unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to assess the proportion of reported proximal contact loss between implant-supported prostheses and adjacent natural teeth. MATERIAL AND METHODS: This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology criteria and was registered on the international prospective register of systematic reviews (PROSPERO) platform (CRD42021225138). The electronic search was conducted by using the PubMed/MEDLINE, Embase, and Cochrane Library databases to September 2020. The formulated population, intervention, comparison, outcome (PICO) question was "Is there a correlation of the proximal contact loss between implant-supported prostheses and the adjacent natural tooth?" A single-arm meta-analysis of proportion was performed to evaluate the cumulative prevalence of survival and complication rates. RESULTS: This review included 10 studies, half of which presented proximal contact loss rates higher than 50%. In the general analysis, the open proximal contact showed a cumulative proportion of 41% (confidence interval: 30% to 53%; heterogeneity: I2=98%; t2=0.578; P<.01). From the subanalysis, the mesial contact (47%; confidence interval: 32% to 62%; heterogeneity: I2= 96%; t2=0.657; P<.01) and the mandibular arch (41%; confidence interval: 30% to 52%; heterogeneity: I2=92%; t2=0.302; P<.01) were found to have higher prevalence. CONCLUSIONS: The prevalence of proximal contact loss was high, occurring more frequently with the mesial contact and in the mandibular arch. Significant differences were not found in relation to sex or between the posterior and anterior regions.

Are implant-supported removable partial dentures a suitable treatment for partially edentulous patients? A systematic review and meta-analysis.

STATEMENT OF PROBLEM: A consensus on the clinical performance of implant-supported removable partial dentures (ISRPDs) is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the clinical performance of ISRPDs in terms of the implant survival rates, marginal bone loss, and patient-reported outcome measures (PROMs). MATERIAL AND METHODS: Four electronic databases (MEDLINE/PubMed, EMBASE, Web of Science, and Cochrane Library) were independently searched by 2 reviewers for articles published up to December 2020. A single-arm meta-analysis was performed to evaluate the implant survival rates and marginal bone loss by using the R program. The Cochrane collaboration tool was used to evaluate the risk of bias of randomized controlled trials (RCTs), and the Newcastle-Ottawa scale for non-RCT studies. RESULTS: Sixteen studies were included, with a total of 334 participants and a mean age of 58 years. The participants received a total of 581 dental implants, 475 conventional and 106 mini-implants. All included studies reported implant survival rate above 90% (range: 92% to 100%). Meta-analysis indicated a high proportion of implant survival rates of 3% (95% confidence interval [CI]: 2% to 5%) and a low mean raw score of marginal bone loss 0.98 mm (CI: 0.61 to 1.36 mm). Compared with conventional RPDs, improved patient quality of life and satisfaction were reported by studies that evaluated ISRPDs. RCT studies exhibited a low risk of bias for most domains, while most non-RCT studies were classified as good quality. CONCLUSIONS: ISRPDs exhibited high implant survival rates and acceptable bone loss with improvement in the quality of life and satisfaction of patients when compared with conventional RPDs. Therefore, they can be considered suitable for the rehabilitation of partially edentulous patients.

Partially digital workflow for making complete-arch implant-supported fixed prostheses: A dental technique.

This article describes a technique for making complete-arch implant-supported fixed prostheses by using intraoral scanning and computer-aided design and computer-aided manufacturing (CAD-CAM) technology for the fabrication of a metal substructure and conventional processing for the prosthesis base. For this, a device was designed to accurately capture the position of multiple implants and the associated digitalized surgical guide, and the metal substructure was planned and milled directly in cobalt-chromium. The color of the gingiva and artificial teeth was selected by using the intraoral scanner software program, and the prosthesis base was processed conventionally. The straightforward methods used to fabricate the prostheses eliminated possible errors associated with conventional substructure casting and occlusal registration.

The influence of nocturnal use of complete dentures on cardiorespiratory parameters of patients with obstructive sleep apnea: a systematic review and meta-analysis.

OBJECTIVE: To assess whether wearing complete dentures during sleep influences the cardiorespiratory parameters of patients with obstructive sleep apnea (OSA). MATERIALS AND METHODS: A systematic review was performed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to determine whether wearing complete dentures during sleep influences the cardiorespiratory parameters of patients with OSA. An electronic search was performed in four databases, PubMed/MEDLINE, Cochrane Library, Web of Science, and SCOPUS, and in the gray literature (TRIALS) until November 2021. This review included clinical trials, randomized clinical trials, and studies in which patients using conventional complete dentures were diagnosed with OSA using polysomnography and the cardiorespiratory parameters were measured using oximetry or polysomnography during sleep. RESULTS: In total, 788 references were found in the database, and 12 articles were selected for full reading. Six articles were selected for qualitative and quantitative analyses after applying the inclusion and exclusion criteria and reading the full article. The meta-analysis showed that mean oxygen saturation (SpO2) increased with the use of complete dentures (p = 0.001), but the other parameters showed no significant differences between those wearing and not wearing dentures during sleep. CONCLUSIONS: The mean SpO2 reduced in patients wearing complete dentures, but the other cardiorespiratory parameters evaluated were not affected. CLINICAL RELEVANCE: This study indicates a possible influence of the use of complete dentures on the mean SpO2 during sleep. The use of complete denture could aid other treatments in improving respiratory and sleep quality.

Survival and prosthetic complications of monolithic ceramic implant-supported single crowns and fixed partial dentures: A systematic review with meta-analysis.

STATEMENT OF PROBLEM: Monolithic ceramic implant-supported restorations have been used to rehabilitate partially edentulous patients. However, knowledge of the survival and prosthetic complications of single crowns (SCs) and fixed partial dentures (FPDs) is limited. PURPOSE: The purpose of this systematic review with meta-analysis was to evaluate the clinical performance of monolithic ceramic implant-supported SCs and FPDs in terms of survival and prosthetic complication rates. MATERIAL AND METHODS: The systematic review was registered on the prospective register of systematic reviews (PROSPERO) (CRD42017078568). Five electronic databases were independently searched by 2 authors for articles published until May 2022. In addition, a hand search was performed in the nonpeer-reviewed literature, specific journals, and reference lists of included articles. A single-arm meta-analysis was performed by using the R program. The risk of bias and quality were assessed using the Cochrane risk of bias tools and the Newcastle-Ottawa scale. RESULTS: Twenty-eight studies were included in the quantitative synthesis. A total of 1298 monolithic ceramic implant-supported restorations (1116 SCs and 182 FPDs) were evaluated in 1193 participants, with a median observation time of 24 months (range: 12 to 72 months). Meta-analysis indicated the proportion of failures and prosthetic complication rates of 2% (95% confidence interval [CI]: 1% to 4%) for SCs. No difference was observed for monolithic zirconia and lithium disilicate SCs. In the FPDs, only monolithic zirconia was considered, with 1 failure reported totaling the proportion of failures of 0% (0% to 1%) and complication rates of 4% (0% to 12%). The most complications reported for both types of restorations were screw loosening, debonding, and minor chipping and were considered repairable. The included studies showed a low risk of bias and good quality. CONCLUSIONS: The use of monolithic ceramic implant-supported SCs, independent of ceramic material, and monolithic zirconia implant-supported FPDs should be considered an effective and safe treatment option because of favorable short-term survival and low prosthetic complications. However, additional well-conducted studies with a longer-term follow-up and direct comparison between veneered restorations are recommended to reassess clinical performance.

Clinical comparison between crestal and subcrestal dental implants: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: How the performance of dental implants is related to their occlusogingival placement, crestal or subcrestal, is unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate marginal bone loss, implant survival rate, and peri-implant soft tissue parameters between implants placed at the crestal and subcrestal bone level. MATERIAL AND METHODS: Two independent reviewers searched the PubMed/MEDLINE, Embase, and Cochrane Library databases for randomized clinical trials published up to September 2020. The meta-analysis was based on the Mantel-Haenszel and the inverse variance methods (α=.05). RESULTS: The search identified 928 references, and 10 studies met the eligibility criteria. A total of 393 participants received 709 implants, 351 at crestal bone levels and 358 at subcrestal bone levels. Meta-analysis indicated that crestal bone level implants showed similar marginal bone loss to that seen with subcrestal bone level implants (mm) (P=.79), independent of the subcrestal level (P=.05) and healing protocol (P=.24). The bone level implant placement did not affect the implant survival rate (P=.76), keratinized tissue (mm) (P=.91), probing depth (mm) (P=.70), or plaque index (%) (P=.92). CONCLUSIONS: The evidence suggests that both approaches of implant placement are clinically acceptable in terms of peri-implant tissue parameters and implant-supported restoration survival.

Mechanical properties of polymethyl methacrylate as a denture base: Conventional versus CAD-CAM resin - A systematic review and meta-analysis of in vitro studies.

STATEMENT OF PROBLEM: The development of polymethyl methacrylate (PMMA) computer-aided design and computer-aided manufacturing (CAD-CAM) resin blocks with reported improved mechanical properties has simplified complete denture production. However, whether the objective of improved mechanical properties has been achieved compared with conventional heat-polymerized PMMA is not yet clear. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the mechanical properties of denture base resins manufactured by conventional heat-polymerization and by CAD-CAM in terms of flexural strength, flexural modulus, and surface roughness. MATERIAL AND METHODS: Electronic databases (PubMed/MEDLINE, Scopus, Web of Science) were independently searched by 2 researchers for relevant studies published up to November 2020. The population, intervention, comparison, and outcome (PICO) question was, "Does the conventionally manufactured, heat-polymerized PMMA resin, as a denture base, demonstrate the same mechanical properties as the CAD-CAM resin block?" In addition, a meta-analysis was based on the inverse variance method. Flexural strength, flexural modulus, and surface roughness were analyzed through the continuous outcome evaluated by mean difference and standard deviation, with 95% confidence intervals. To evaluated heterogeneity, the I2 value (≤25%=low, ≥50%=moderate and ≥75%=high) and the P value were considered. P<.10 indicated statistical difference for heterogeneity. The effects of meta-analysis were based on the results of heterogeneity as per the studies. RESULTS: Thirteen in vitro studies were included in the analysis. A total of 507 specimens were evaluated, 222 conventional and 285 CAD-CAM. In terms of flexural strength, the data showed no significant difference when conventional heat-polymerized PMMA was compared with CAD-CAM PMMA resins (P=.06; mean difference=18.28; 95% confidence interval:-0.42 to 36.97). In terms of flexural modulus, there was a significant difference for the CAD-CAM PMMA group (P=.01; mean difference=589.22; 95% confidence interval: 117.95 to 1060.48). In terms of surface roughness, a significant difference was observed between the groups (P=.02; mean difference=-0.53; 95% confidence interval: -0.97 to -0.09) with the conventional heat-polymerized PMMA resin having higher surface roughness values. CONCLUSIONS: The mechanical properties of CAD-CAM PMMA resins were generally improved when compared with heat-polymerized polymethyl methacrylate resin.

Does the use of an adhesive improve conventional complete dentures? A systematic review of randomized controlled trials.

STATEMENT OF PROBLEM: A consensus on whether the use of a complete-denture adhesive provides a clinical benefit remains unclear. PURPOSE: The purpose of this systematic review of randomized controlled trials was to evaluate the use of adhesive in complete dentures in terms of retention and stability, patient-reported outcomes measures, and masticatory performance. MATERIAL AND METHODS: A search was performed in PubMed, Web of Science, and Cochrane Library for articles up to October 2020. The Cochrane collaboration tool was used to analyze the risk of bias. The grading quality of evidence and strength of recommendations (GRADE) tool was used to assess the certainty of the evidence. RESULTS: Thirteen studies were included with a total of 516 participants with a mean age of 65.5 years. Most studies reported a significant improvement in the retention and stability, patient-reported outcomes measures, and masticatory performance of complete dentures with the use of denture adhesive compared with no-denture adhesive. Newly developed denture adhesives were reported to have promising results. Most studies presented a low risk of bias, but the certainty of the evidence was classified as low to moderate. CONCLUSIONS: Participants had improved treatment outcomes when using denture adhesives because they significantly improve the retention and stability, patient-reported outcomes measures, and masticatory performance. However, further high-quality studies are needed to confirm these results with newly developed denture adhesives.

Biomechanical Evaluation of Different Implant-Abutment Connections, Retention Systems, and Restorative Materials in the Implant-Supported Single Crowns Using 3D Finite Element Analysis.

This is an in silico study aimed to evaluate the biomechanical influence of different implant-abutment interfaces (external hexagon and Morse taper implants), retention systems (cement and screw retained), and restorative crowns (metal-ceramic and monolithic) using 3-dimensional finite element analysis (3D-FEA). Eight 3D models were simulated for the maxillary first molar area using InVesalius, Rhinoceros, and SolidWorks and processed using Femap and NEi Nastran software. Axial and oblique forces of 200 and 100 N, respectively, were applied on the occlusal surface of the prostheses. Microstrain and von Mises stress maps were used to evaluate the deformation (cortical bone tissue) and stress (implants/fixation screws/crowns), respectively, for each model. For both loadings, Morse taper implants had lower microstrain values than the external hexagon implants. The retention system did not affect microstrain on the cortical bone tissue under both loadings. However, the cemented prosthesis displayed higher stress with the fixation screw than the external hexagon implants. No difference was observed between the metal-ceramic and zirconia monolithic crowns in terms of microstrain and stress distribution on the cortical bone, implants, or components. Morse taper implants can be considered as a good alternative for dental implant rehabilitation because they demonstrated better biomechanical behavior for the bone and fixation screw as compared to external hexagon implants. Cement-retained prosthesis increased the stress on the fixation screw of the external hexagon implants, thereby increasing the risk of screw loosening/fracture in the posterior maxillary area. The use of metal-ceramic or monolithic crowns did not affect the biomechanical behavior of the evaluated structures.

Assessment of the cytoprotective effect of the homeopathic compound Canova® on African green monkey kidney (VERO) cell line exposed to the drug dipyrone sodium.

Dipyrone or metamizole is one of the most frequently used analgesic worldwide. Despite its widespread use, this drug may exert genotoxic and cytotoxic effects on lymphocytes. Therefore, studies with therapeutic agents that may provide protection against these effects are important. The homeopathic compound Canova® (CA) appears to be a beneficial candidate for preventing DNA damage and cellular lethality, since this compound acts as an immunomodulator associated with cytoprotective actions. Hence, the aim of the present investigation was to determine the potential cytoprotective effects of CA using cell line VERO as a model. VERO cells were incubated with sodium dipyrone and subsequently subject to the comet, apoptosis and immunocytochemistry assays. Data demonstrated that sodium dipyrone induced an increase in DNA damage index (DI) employing the comet assay. However, when VERO cells were co-treated with CA at the three concentrations studied, a significant reduction in DI was observed, indicating an antigenotoxic effect attributed to CA. Further dipyrone induced an elevation in %apoptosis at 24 and 48 hr. However, when dipyrone was co-incubated with CA, a significant reduction in %apoptosis was noted at the three concentrations of CA employed. Results from immunocytochemical analysis showed a rise in the expression of caspase 8 and cytochrome C when cells were exposed to dipyrone. In contrast, co-treatment of dipyrone and CA significantly reduced the effect of dipyrone. Therefore, evidence indicated that CA acted as an anticytotoxic and antigenotoxic agent counteracting damage induced by dipyrone.

Does nocturnal use of a complete denture interfere with the degree of obstructive sleep apnea? A systematic review and meta-analysis.

BACKGROUND: The impact of a complete denture on obstructive sleep apnea is not well understood. Therefore, this study aimed to evaluate the relationship between nighttime use of complete dentures and obstructive sleep apnea and determine if wearing a complete denture during sleep changes the degree of obstructive sleep apnea. METHODS: This systematic review followed the notification items for Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and was recorded in the International Prospective Registry of Systematic Reviews (PROSPERO) under number CRD42020183167. An electronic search in the PubMed/MEDLINE, Scopus, and Cochrane Library databases for articles published until September 2020 was conducted. The search strategy used the terms (complete denture OR denture OR edentulous OR edentulism) AND (quality of sleep OR sleep OR apnea OR obstructive sleep apnea). Only prospective, retrospective, controlled, and randomized clinical studies of patients wearing complete dentures, studies comparing sleep with and without the prosthesis, and studies in which patients were diagnosed with obstructive sleep apnea by polysomnography were included in the review. RESULTS: In total, four articles were selected for the qualitative and quantitative analyses. A total of 144 patients, with an average age of 60 years, were studied. The meta-analysis showed that there was no statistical difference in the apnea-hypopnea index between using and not using the prosthesis during sleep. CONCLUSIONS: The use of complete dentures during sleep does not influence the degree of obstructive sleep apnea.

Postoperative pain in endodontic retreatment of one visit versus multiple visits: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: The aim of this systematic review and meta-analysis (SRM) was to assess the postoperative pain (PP) after non-surgical endodontic retreatment (NSER) in a one visit compared to multiple visits. The PICO question used was "Does NSER in patients with unsatisfactory endodontic treatment in a one-visit visit have a similar PP to that of NSER in multiple visits?" MATERIALS AND METHODS: This systematic review followed PRISMA and was registered in PROSPERO (CRD42019136700). Searches were performed in the PubMed/MEDLINE, Scopus, and the Cochrane Library databases for articles published until September 2020. The eligible criteria were randomized clinical trials (RCTs). The meta-analysis was based on the Mantel-Haenszel. The PP after the retreatment was analyzed using a dichotomous outcome, measured according to risk ratio (RR) when p < 0.05. The Cochrane scale was used to assess risk of bias, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the quality of evidence. RESULTS: Four studies were included. In general analysis without considering intensity, one-visit NSER presented lower PP than the multiple visits only for 1 and 30 days [(RR = 0.67; CI: 0.48 to 0.93; p = 0.02), and (RR = 0.09; CI: 0.01 to 0.66; p = 0.02)], respectively. Regarding sub-analysis considering the intensity, one visit present lower mild PP when compared with multiple visits [(RR = 0.54; CI: 0.30, 0.96; p = 0.04); (RR = 0.33; CI: 0.12, 0.88; p = 0.03); and (RR = 0.12; CI: 0.02, 0.86; p = 0.03)], respectively. However, sub-analysis for moderate and severe PP showed no significant difference, independently of period evaluated (p > 0.05). Regarding the risk of bias analysis, a low risk was observed for most domains, except allocation that was considered unclear, while the certainty of evidence for each analysis was considered low. CONCLUSION: Within the limitations of study, the one and multiple visit can be considered adequate, because both present a similar occurrence of PP, except for mild pain. However, due to the low number of studies, further well conducted and standardized RCTs are needed to reassess these results. CLINICAL RELEVANCE: Both therapies of endodontic retreatment can be considered in clinical practice. Therefore, the endodontist must consider the patient's individual characteristics and experience to consider the best treatment approach.

Clinical effect of the high insertion torque on dental implants: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: A consensus on the clinical performance in dental implants placed with different insertion torques is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the effect of high insertion torque compared with regular or low torques during dental implant placement in terms of implant survival rate and marginal bone loss. MATERIAL AND METHODS: Two independent reviewers searched electronic databases for studies published until April 2019. The population, intervention, comparison, outcome (PICO) question was "Do patients who receive implants with a high torque (equal or higher than 50 Ncm) show similar implant survival rates and marginal bone loss as compared with those who receive implants with a regular or low torque (less than 50 Ncm)?". The meta-analysis was based on the Mantel-Haenszel (MH) and the inverse variance (IV) methods (α=.05). RESULTS: The search yielded 6 articles, which included 389 patients (mean age: 55.28 years) who had received 651 dental implants (437 with high torque and 214 with low or regular torque). Most studies evaluated delayed loading, except 1 study that evaluated immediate implant loading (n=50 for each group). Low or regular insertion torque had a high failure rate (4.2%) compared with high insertion torque (1.1%), chiefly because of immediate loading. However, the meta-analysis indicated no significant difference between high- and regular- or low-torque implant placement in implant survival rate (P=.52, risk ratio [RR]: 0.51, 95% confidence interval [CI]: 0.06-4.06) and marginal bone loss (P=.30, mean difference [MD]: 0.15, 95% CI: -0.14 to 0.44). CONCLUSIONS: A high insertion torque during implant placement does not affect implant survival rate or marginal bone loss. However, further research is recommended to reassess this clinical performance.

The influence of crown-to-implant ratio in single crowns on clinical outcomes: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: A consensus about the effect of crown-to-implant (C/I) ratio in single crowns regarding the implant survival rate and marginal bone loss (MBL) is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the influence of C/I ratio in implant-supported single crowns on clinical outcomes. MATERIAL AND METHODS: The search was made in the PubMed/MEDLINE, Scopus, and the Cochrane Library databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria and registered with the International Prospective Register of Systematic Reviews (PROSPERO: CRD42018095711). The focused question was "Does the crown-to-implant ratio influence clinical outcomes for implant-supported single crowns?" RESULTS: Five direct comparative studies were included (C/I ratio ≤1 or >1, or ≤2 or >2), including a total of 262 participants with a mean age of 54.5 years. The meta-analysis comparing C/I ratio between ≤1 or >1 revealed no significant differences (P=.18; risk difference:-0.05; 95% confidence interval: -0.11 to 0.02) in terms of implant survival rate; the same was true for C/I ratio between <2 or ≥2 (P=.05; risk difference:-0.06; 95% confidence interval: -0.12 to -0.00), both analysis were made with a mean follow-up period was 36 months. The mean MBL was calculated based in the qualitative data for each C/I ratio: ≤1 (0.15 mm [-0.34 to 0.34]); >1 (0.07 mm [-0.29 to 0.22]); <2 (1.32 mm [0.38-0.9]); and ≥2 (1.37 mm [-0.02 to 0.91]). The qualitative data reported that the most common mechanical complication was screw loosening, and the most common biological complication was peri-implantitis. CONCLUSIONS: The meta-analysis revealed no relationship between categories of C/I ratio for implant survival rate. The qualitative data also suggested that MBL increased as the C/I ratio increased.