Monumental architecture at Aguada Fénix and the rise of Maya civilization.

Archaeologists have traditionally thought that the development of Maya civilization was gradual, assuming that small villages began to emerge during the Middle Preclassic period (1000-350 BC; dates are calibrated throughout) along with the use of ceramics and the adoption of sedentism1. Recent finds of early ceremonial complexes are beginning to challenge this model. Here we describe an airborne lidar survey and excavations of the previously unknown site of Aguada Fénix (Tabasco, Mexico) with an artificial plateau, which measures 1,400 m in length and 10 to 15 m in height and has 9 causeways radiating out from it. We dated this construction to between 1000 and 800 BC using a Bayesian analysis of radiocarbon dates. To our knowledge, this is the oldest monumental construction ever found in the Maya area and the largest in the entire pre-Hispanic history of the region. Although the site exhibits some similarities to the earlier Olmec centre of San Lorenzo, the community of Aguada Fénix probably did not have marked social inequality comparable to that of San Lorenzo. Aguada Fénix and other ceremonial complexes of the same period suggest the importance of communal work in the initial development of Maya civilization.

The Impact of Modeling Liquids on Surface Roughness and Color Properties of Bulkfill Resin Composites After Simulated Tooth Brushing: An in Vitro Study. Part I.

OBJECTIVE: To evaluate the effect of different modeling agents on color changes, surface roughness, and translucency parameters over time in Bulkfill resin composites. MATERIAL AND METHODS: Sixty specimens were prepared using three Bulkfill resin composites (Tetric N-Ceram Bulkfill, Filtek One Bulkfill and Opus Bulkfill) and three modeling agents (Wetting Resin, Optibond FL and Ambar APS). All specimens were subjected to a simulated tooth-brushing (Baseline, 50.000 cycles, 100.000 cycles), and surface roughness was measured at each interval. Surface topography was evaluated. The translucency parameter and color changes were assessed after 24-h, 7-, 14- and 30-day immersion in water, wine, and coffee. Data was analyzed using ANOVA and Bonferroni test. RESULTS: All specimens increased roughness after simulated tooth-brushing (p < 0.05). Wetting Resin decreased roughness on Tetric N-Ceram Bulkfill (p < 0.05). The translucency parameter remained unaltered for all groups. All groups changed color after 30-days of immersion in wine and coffee (p < 0.05). Ambar APS and Wetting Resin on Tetric N-Ceram Bulkfill showed higher color changes when immersed in coffee (p < 0.05). CONCLUSION: The use of modeling agents does not jeopardize translucency properties but may affect surface roughness and color properties of Bulkfill resin composites depending on their composition. CLINICAL SIGNIFICANCE: The findings of this study suggest that surface roughness and color properties are affected by the differences in the composition between modeling agents and Bulkfill resins composites.

Nutritional Aspects of Spermidine.

Natural polyamines (spermidine and spermine) are small, positively charged molecules that are ubiquitously found within organisms and cells. They exert numerous (intra)cellular functions and have been implicated to protect against several age-related diseases. Although polyamine levels decline in a complex age-dependent, tissue-, and cell type-specific manner, they are maintained in healthy nonagenarians and centenarians. Increased polyamine levels, including through enhanced dietary intake, have been consistently linked to improved health and reduced overall mortality. In preclinical models, dietary supplementation with spermidine prolongs life span and health span. In this review, we highlight salient aspects of nutritional polyamine intake and summarize the current knowledge of organismal and cellular uptake and distribution of dietary (and gastrointestinal) polyamines and their impact on human health. We further summarize clinical and epidemiological studies of dietary polyamines.

Assessment of the effect of experimental bleaching agent with nano-bioactive material on postoperative sensitivity: A randomized, triple blind clinical trial.

OBJECTIVES: This clinical study aimed to evaluate the effect of incorporating bioactive nanoparticles (n-Bm) inside an in-office bleaching gel on the risk and intensity of tooth sensitivity (TS) and on bleaching effectiveness. MATERIALS AND METHODS: Sixty-six participants were selected and randomly assigned into two groups: control-only in-office gel and experimental-in-office gel with n-Bm. Teeth were bleached in two sessions (3 × 15-min). TS was recorded using a VAS and NRS. The color change was evaluated by subjective (VITA Classical and VITA Bleachedguide) and objective (Easyshade spectrophotometer) methods at baseline and 30 days after the end of treatment. The TS was evaluated by McNemar, Wilcoxon Signed Rank, and paired t test. The color changes between groups were compared using paired t test (α = 0.05). RESULTS: No significant differences between the groups were observed in the risk (control = 27% [95%IC 18-39]; experimental = 21% [95%IC 13-32]) and intensity of TS, as well as in the color change (p >0.05) for any color measurement. CONCLUSION: The inclusion of n-Bm into the bleaching agents did not affect the whitening effectiveness, as well as the risk and intensity of TS between groups. However, the results of the absolute risk of TS were low for both in-office gels used. CLINICAL SIGNIFICANCE: Despite no significant differences between groups, both experimental bleaching agents present suitable results with low values for TS.

The role of HIF-1α in nicotine-induced root and bone resorption during orthodontic tooth movement.

BACKGROUND: In orthodontic tooth movement (OTM), pseudo-inflammatory processes occur that are similar to those of nicotine-induced periodontitis. Previous studies have shown that nicotine accelerates OTM, but induces periodontal bone loss and dental root resorption via synergistically increased osteoclastogenesis. This study aimed to investigate the role of hypoxia-inducible factor 1 alpha (HIF-1α) in nicotine-induced osteoclastogenesis during OTM. MATERIALS/METHODS: Male Fischer-344 rats were treated with l-Nicotine (1.89 mg/kg/day s.c., N = 10) or NaCl solution (N = 10). After a week of premedication, a NiTi spring was inserted to mesialize the first upper left molar. The extent of dental root resorption, osteoclastogenesis, and HIF-1α protein expression was determined by (immuno)histology, as well as bone volume (BV/TV) and trabecular thickness (TbTh) using µCT. Receptor activator of nuclear factor of activated B-cells ligand (RANK-L), osteoprotegerin (OPG), and HIF-1α expression were examined at the protein level in periodontal ligament fibroblasts (PDLF) exposed to pressure, nicotine and/or hypoxia, as well as PDLF-induced osteoclastogenesis in co-culture experiments with osteoclast progenitor cells. RESULTS: Nicotine favoured dental root resorptions and osteoclastogenesis during OTM, while BV/TV and TbTh were only influenced by force. This nicotine-induced increase does not appear to be mediated by HIF-1α, since HIF-1α was stabilized by force application and hypoxia, but not by nicotine. The in vitro data showed that the hypoxia-induced increase in RANK-L/OPG expression ratio and PDLF-mediated osteoclastogenesis was less pronounced than the nicotine-induced increase. CONCLUSIONS: Study results indicate that the nicotine-induced increase in osteoclastogenesis and periodontal bone resorption during OTM may not be mediated by hypoxic effects or HIF-1α stabilization in the context of nicotine-induced vasoconstriction, but rather by an alternative mechanism.

Characteristics of cystic fibrosis-related diabetes: Data from two different sources the European cystic fibrosis society patient registry and German/Austrian diabetes prospective follow-up registry.

BACKGROUND: Standardized patient registries provide a unique basis to get insight into cystic fibrosis (CF)-related diabetes (CFRD), the most common comorbidity in CF. METHODS: A total of 3853 CFRD patients from the European CF Society Patient Registry (ECFSPR) and 752 from the German/Austrian diabetes prospective follow-up (diabetes patienten verlaufsdokumentation [DPV]) were studied. To adjust for age and sex, multivariable regression was used (SAS 9.4). RESULTS: DPV subjects were younger (26.5 [20.2-32.6] vs 28.3 [21.7-36.0] years, P < 0.001) and more often female (59.6 vs 50.9%, P < 0.001). In both registries, F508del homozygotes were most frequent, with higher proportion in DPV (80.9 vs 57.8%, P = 0.003). After adjustment, lung-transplantation (LTX) was more common in ECFSPR (18.9 vs 4.9%, P < 0.001), although duration since LTX (4.8 ± 0.2 vs 5.5 ± 0.7 years, P = 0.33) did not differ. In DPV patients without LTX, a lower BMI (19.6 ± 0.1 vs 21.0 ± 0.1 kg/m2 , P < 0.001), higher proportion of underweight (41.2 vs 20.2%, P < 0.001) and a tendency towards worse lung function (%FEV1 : 42.3 ± 4.2 vs 48.3 ± 0.5%, P = 0.16) were observed. CONCLUSIONS: Between both registries, demographic and clinical differences of CFRD were present. Besides different kind of data sources, diverse treatment structures between countries may play a role. The results may further indicate a more serious illness in patients treated in specialized diabetes clinics, documenting their data in DPV.

Perioperative redistribution of regional ventilation and pulmonary function: a prospective observational study in two cohorts of patients at risk for postoperative pulmonary complications.

BACKGROUND: Postoperative pulmonary complications (PPCs) increase morbidity and mortality of surgical patients, duration of hospital stay and costs. Postoperative atelectasis of dorsal lung regions as a common PPC has been described before, but its clinical relevance is insufficiently examined. Pulmonary electrical impedance tomography (EIT) enables the bedside visualization of regional ventilation in real-time within a transversal section of the lung. Dorsal atelectasis or effusions might cause a ventral redistribution of ventilation. We hypothesized the existence of ventral redistribution in spontaneously breathing patients during their recovery from abdominal and peripheral surgery and that vital capacity is reduced if regional ventilation shifts to ventral lung regions. METHODS: This prospective observational study included 69 adult patients undergoing elective surgery with an expected intermediate or high risk for PPCs. Patients undergoing abdominal and peripheral surgery were recruited to obtain groups of equal size. Patients received general anesthesia with and without additional regional anesthesia. On the preoperative, the first and the third postoperative day, EIT was performed at rest and during spirometry (forced breathing). The center of ventilation in dorso-ventral direction (COVy) was calculated. RESULTS: Both groups received intraoperative low tidal volume ventilation. Postoperative ventral redistribution of ventilation (forced breathing COVy; preoperative: 16.5 (16.0-17.3); first day: 17.8 (16.9-18.2), p < 0.004; third day: 17.4 (16.2-18.2), p = 0.020) and decreased forced vital capacity in percentage of predicted values (FVC%predicted) (median: 93, 58, 64%, respectively) persisted after abdominal surgery. In addition, dorsal to ventral shift was associated with a decrease of the FVC%predicted on the third postoperative day (r = - 0.66; p < 0.001). A redistribution of pulmonary ventilation was not observed after peripheral surgery. FVC%predicted was only decreased on the first postoperative day (median FVC%predicted on the preoperative, first and third day: 85, 81 and 88%, respectively). In ten patients occurred pulmonary complications after abdominal surgery also in two patients after peripheral surgery. CONCLUSIONS: After abdominal surgery ventral redistribution of ventilation persisted up to the third postoperative day and was associated with decreased vital capacity. The peripheral surgery group showed only minor changes in vital capacity, suggesting a role of the location of surgery for postoperative redistribution of pulmonary ventilation. TRIAL REGISTRATION: This prospective observational single centre study was submitted to registration prior to patient enrollment at ClinicalTrials.gov (NCT02419196, Date of registration: December 1, 2014). Registration was finalized at April 17, 2015.

Expiratory Central Airway Collapse in Adults: Corrective Treatment (Part 2).

Corrective treatment of expiratory central airway collapse (ECAC) consists of placement of airway stents or tracheobronchoplasty (TBP). The indication for corrective treatment is severe central airway collapse (>90 %), and severe symptoms that cause decline in quality of life. Patients are selected to undergo a trial of tracheal "Y" stent placement. If symptoms improve (positive trial) they undergo a TBP, provided they are good surgical candidates. Patients who are considered poor surgical candidates because of the severity of comorbidities can be offered permanent stenting to palliate symptoms. The anesthetic management of airway stent placement and TBP is complex. This article reviews the medical management and corrective treatment of ECAC, anesthetic management of airway stent placement, and considerations during TBP.

Expiratory Central Airway Collapse in Adults: Anesthetic Implications (Part 1).

Expiratory central airway collapse (ECAC) is a general term that incorporates tracheobronchomalacia (TBM) and excessive dynamic airway collapse (EDAC). TBM and EDAC are progressive, degenerative disorders of the tracheobronchial tree, causing airway collapse. Induction of general anesthesia can trigger intraoperative airway collapse in patients with these conditions. This crisis presents as the sudden inability to ventilate, which can lead to life-threatening hypoxemia and hypercapnia. This article reviews the definition, pathophysiology, diagnosis, and anesthetic implications of ECAC.

Incidence of intraoperative hypersensitivity reactions: a registry analysis: a registry analysis.

BACKGROUND: Previously reported incidences for intraoperative hypersensitivity reactions vary more than 15-fold. The goal was to determine the incidence of intraoperative hypersensitivity events at a U.S. surgical center. METHODS: With institutional review board (Cleveland, Ohio) approval and waiver of written/informed consent, the anesthesia records of adult patients undergoing noncardiac surgery from 2005 to 2011 at the Cleveland Clinic were queried using a novel electronic search protocol developed to identify potential hypersensitivity reactions: cardiovascular collapse defined as systolic arterial blood pressure less than 50 mmHg; administration of epinephrine; administration of diphenhydramine; physician comments in the anesthesia record suggestive of hypersensitivity reactions; laboratory tests for histamine, tryptase, or immunoglobulin-E within 24 h of surgery; and International Classification of Diseases, Ninth Revision, codes suggestive of hypersensitivity reactions. Each electronically identified candidate chart was evaluated by an adjudication committee. Hypersensitivity reactions were graded on a 5-point severity scale. From these data, the authors determined the proportion of operations having adjudicated hypersensitivity reactions, and calculated the 95% exact binomial CI. RESULTS: Among 178,746 records, 4,008 charts were identified by the search strategies. After adjudication, 264 hypersensitivity cases were identified. The overall incidence of hypersensitivity reactions was 1:677 surgeries, corresponding to 15 (95% CI, 13 to 17) cases per 10,000 operations. The incidence of severe hypersensitivity reactions (grades 3 to 5) was 1:4,583, corresponding to 2 (95% CI, 2 to 3) cases per 10,000 operations. CONCLUSIONS: The incidence of severe hypersensitivity reactions was similar to previous reports. However, the overall incidence of hypersensitivity reactions was much greater than reported elsewhere, possibly because of a comprehensive search strategy.

Innate immune function after breast, lung, and colorectal cancer surgery.

BACKGROUND: The cytotoxic activity and count of natural killer (NK) cells appear to be reduced after surgery; however, it is unknown whether the magnitude of this immune suppression is similar among different types of oncological surgery. In this study, we compared the innate immune function of patients undergoing three different oncological surgeries. METHODS: We compared the number and function of NK cells obtained from patients who had undergone mastectomies (n = 17), thoracotomies (n = 21), or liver resections for cancer (n = 22). Cytotoxicity assays were performed to measure the function of NK cells. We also determined the plasma concentrations of interleukins (IL) 2 and 4, interferon-γ, granzyme B, perforin, soluble major histocompatibility complex class I-related chain A, and epinephrine, both before and 24 h after surgery. Differences in immunologic parameters were compared preoperatively and postoperatively and by type of surgery. P values <0.05 were considered statistically significant. RESULTS: The preoperative NK cell count differed statistically (P < 0.006) among all three types of surgeries; however, within surgery postoperative counts and changes compared with baseline did not. The postoperative function of NK cells was similar among types of surgeries, but was significantly reduced compared with preoperative levels (mastectomy P < 0.0001, thoracotomy P = 0.001, and liver resections P = 0.002). We observed a significant increase in the postoperative plasma concentrations of epinephrine, whereas the concentrations of major histocompatibility class I polypeptide-related sequence A and the IL-2 and/or IL-4 ratio remained unchanged before and after surgery. CONCLUSIONS: The magnitude of innate immune suppression is similar among different oncological procedures. More studies are needed to better understand this complex phenomenon.

Culicoides castelloni sp. nov. from the Brazilian Amazon Region with a revision of the reticulatus species group (Diptera, Ceratopogonidae).

A new species of the reticulatus species group, C. castelloni Santarém and Felippe-Bauer, is described and illustrated based on female specimens from the state of Amazonas, Brazil. A systematic key, wing photographs and table with numerical characters of females and a synopsis of 24 species of the Culicoides reticulatus group are presented. This paper presents further new records for seven species of the reticulatus group.

Comparison of three techniques for ultrasound-guided femoral nerve catheter insertion: a randomized, blinded trial.

BACKGROUND: Ultrasound guidance for continuous femoral perineural catheters may be supplemented by electrical stimulation through a needle or through a stimulating catheter. The authors tested the primary hypothesis that ultrasound guidance alone is noninferior on both postoperative pain scores and opioid requirement and superior on at least one of the two. Second, the authors compared all interventions on insertion time and incremental cost. METHODS: Patients having knee arthroplasty with femoral nerve catheters were randomly assigned to catheter insertion guided by: (1) ultrasound alone (n = 147); (2) ultrasound and electrical stimulation through the needle (n = 152); or (3) ultrasound and electrical stimulation through both the needle and catheter (n = 138). Noninferiority between any two interventions was defined for pain as not more than 0.5 points worse on a 0 to 10 verbal response scale and for opioid consumption as not more than 25% greater than the mean. RESULTS: The stimulating needle group was significantly noninferior to the stimulating catheter group (difference [95% CI] in mean verbal response scale pain score [stimulating needle vs. stimulating catheter] of -0.16 [-0.61 to 0.29], P < 0.001; percentage difference in mean IV morphine equivalent dose of -5% [-25 to 21%], P = 0.002) and to ultrasound-only group (difference in mean verbal response scale pain score of -0.28 [-0.72 to 0.16], P < 0.001; percentage difference in mean IV morphine equivalent dose of -2% [-22 to 25%], P = 0.006). In addition, the use of ultrasound alone for femoral nerve catheter insertion was faster and cheaper than the other two methods. CONCLUSION: Ultrasound guidance alone without adding either stimulating needle or needle/catheter combination thus seems to be the best approach to femoral perineural catheters.

Intrathecal ketorolac does not improve acute or chronic pain after hip arthroplasty: a randomized controlled trial.

Hypersensitivity to mechanical stimuli following surgery has been reported in patients who subsequently develop chronic pain after surgery. In animals, peripheral injury increases prostaglandin production in the spinal cord, and spinal cyclooxygenase inhibitors reduce hypersensitivity after injury. We therefore tested the hypothesis that spinal ketorolac reduces hypersensitivity and acute and chronic pain after hip arthroplasty ( www.clinicaltrials.gov NCT 00621530). Sixty-two patients undergoing total hip arthroplasty with spinal anesthesia were randomized to receive 13.5 mg hyperbaric bupivacaine with spinal saline or 13.5 mg hyperbaric bupivacaine with 2 mg preservative-free ketorolac. The primary outcome was area of hypersensitivity surrounding the wound 48 h after surgery, but this only occurred in 4 patients, precluding assessment of this outcome. The groups did not differ in acute pain, acute opioid use, or pain incidence or severity at 2 and 6 months after surgery. There were no serious adverse events. Our results suggest that a single spinal dose of ketorolac does not substantially reduce acute surgical pain and is thus unlikely to reduce the risk of persistent incisional pain.

New Neotropical Culicoides and redescription of Culicoides reticulatus Lutz (Diptera: Ceratopogonidae).

Seven new species of the Culicoides reticulatus species group are described and illustrated based on specimens from Colombia, Panama and Brazilian states of northern (Amazonas, Pará and Roraima) and southeast region (Rio de Janeiro). The new species are compared with their similar congener, Culicoides reticulatus Lutz, and a systematic key, table with numerical characters to the females of the species are provided. Redescription of Culicoides reticulatus Lutz is given based on type series deposited in the Ceratopogonidae Collection of the Oswaldo Cruz Foundation, Brazil. The distribution of these species is presented in figure 9.

Assessing chronological aging in Saccharomyces cerevisiae.

Chronological age represents the time that passes between birth and a given date. To understand the complex network of factors contributing to chronological lifespan, a variety of model organisms have been implemented. One of the best studied organisms is the yeast Saccharomyces cerevisiae, which has greatly contributed toward identifying conserved biological mechanisms that act on longevity. Here, we discuss high- und low-throughput protocols to monitor and characterize chronological lifespan and chronological aging-associated cell death in S. cerevisiae. Included are propidium iodide staining with the possibility to quantitatively assess aging-associated cell death via flow cytometry or qualitative assessments via microscopy, cell viability assessment through plating and cell counting and cell death characterization via propidium iodide/AnnexinV staining and subsequent flow cytometric analysis or microscopy. Importantly, all of these methods combined give a clear picture of the chronological lifespan under different conditions or genetic backgrounds and represent a starting point for pharmacological or genetic interventions.

Clinical performance of posterior restorations using a universal adhesive over moist and dry dentin: A 36-month double-blind split-mouth randomized clinical trial.

OBJECTIVES: To evaluate the influence of dentin moisture on the clinical behavior of a universal adhesive on posterior teeth after 36 months of follow-up. METHODS: Forty-five patients participated in this study. Following a split-mouth design, three operators placed 90 Class I/Class II restorations over moist dentin (MD) or dry (DD) (n = 45) with resin composite (Filtek Bulk Fill) and a universal adhesive used in the etch-and-rinse mode (Single Bond Universal). Each restoration was evaluated according to the FDI and USPHS criteria (postoperative sensitivity, fracture and retention, marginal staining, marginal adaptation, and recurrence of caries) at baseline and after 6-, 12-, and 36 months. For statistical analysis, Kruskal Wallis analysis of variance rank (α = 0.05) and Kaplan-Meier survival analysis were used. RESULTS: No significant difference between groups was observed in each FDI criterion after 36 months of clinical evaluation (p > 0.05). The retention rates (confidence interval 95 %) were 97.37 % (86.5 - 99.5) for both MD and DD without significant difference between them (p > 0.05). Eight restorations (MD = 4; DD = 4) showed minimal marginal staining defects (p > 0.05). Two restorations were lost (MD = 1; DD = 1). Fifteen restorations (MD = 8; DD = 7) presented minor marginal discrepancies according to the FDI criteria (p > 0.05). CONCLUSION: The clinical performance of the universal adhesive when applied in etch-and-rinse mode was not influenced by dentin moisture in posterior bulk-fill composite restorations. CLINICAL SIGNIFICANCE: The level of dentin moisture appears not to influence the clinical efficacy of a universal adhesive when applied using the etch-and-rinse technique in posterior composite resin restorations.

New Culicoides Latreille of the subgenus Mataemyia Vargas from Pará, Brazil (Diptera: Ceratopogonidae).

Two new species of Culicoides Latreille of the Neotropical subgenus Mataemyia Vargas are described and illustrated based on female specimens from Juruti, Pará, Brazil and compared with their similar congeners. This paper also presents a diagnosis of the subgenus Mataemyia and a systematic key for the identification of the 19 species of the subgenus.

Neonatal exposure to hypoxia induces early arterial stiffening via activation of lysyl oxidases.

Hypoxia in the neonatal period is associated with early manifestations of adverse cardiovascular health in adulthood including higher risk of hypertension and atherosclerosis. We hypothesize that this occurs due to activation of lysyl oxidases (LOXs) and the remodeling of the large conduit vessels, leading to early arterial stiffening. Newborn C57Bl/6 mice were exposed to hypoxia (FiO2  = 11.5%) from postnatal day 1 (P1) to postnatal day 11 (P11), followed by resumption of normoxia. Controls were maintained in normoxia. Using in vivo (pulse wave velocity; PWV) and ex vivo (tensile testing) arterial stiffness indexes, we determined that mice exposed to neonatal hypoxia had significantly higher arterial stiffness compared with normoxia controls by young adulthood (P60), and it increased further by P120. Echocardiography performed at P60 showed that mice exposed to hypoxia displayed a compensated dilated cardiomyopathy. Western blotting revelated that neonatal hypoxia accelerated age-related increase in LOXL2 protein expression in the aorta and elevated LOXL2 expression in the PA at P11 with a delayed decay toward normoxic controls. In the heart and lung, gene and protein expression of LOX/LOXL2 were upregulated at P11, with a delayed decay when compared to normoxic controls. Neonatal hypoxia results in a significant increase in arterial stiffness in early adulthood due to aberrant LOX/LOXL2 expression. This suggests an acceleration in the mechanical decline of the cardiovascular system, that contributes to increased risk of hypertension in young adults exposed to neonatal hypoxia that may increase susceptibility to further insults.

A 24-month clinical evaluation of composite resins with different viscosity and chemical compositions: a randomized clinical trial.

OBJECTIVES: To evaluate the clinical performance of two methacrylate-based flowable composites and an ormocer-based flowable composite in noncarious cervical lesions (NCCLs) in adult participants. METHOD AND MATERIALS: In total, 183 restorations were performed on NCCLs. All cavities were restored using a universal adhesive system (Futurabond U, Voco) with selective enamel etching and with one of the three evaluated flowable composites (n = 61): low-viscosity methacrylate-based composite (GrandioSO Flow, LV), high-viscosity methacrylate-based composite (GrandioSO Heavy Flow, HV), and an ormocer-based flowable composite (Admira Fusion Flow, ORM). All restorations were evaluated using FDI and USPHS criteria after 24 months. Kruskall-Wallis analysis of variance rank (α = .05) was used for statistical analysis. RESULTS: After 24 months of clinical evaluation, 16 restorations were lost (LV = 3, HV = 10, ORM = 3) and the retention rates (95% confidence interval) were 95.0% for LV, 82.2% for HV, and 95.0% for ORM, with statistical differences observed between HV and LV as well as HV and ORM (P < .05). When secondary parameters were evaluated, no significant differences between groups were observed (P > .05). Thirty-three restorations (LV = 8, HV = 13, ORM = 12) showed minor marginal staining, 71 restorations (LV = 26, HV = 20, ORM = 25) presented small marginal adaptation defects, and one restoration for HV presented recurrence of caries. CONCLUSION: The universal adhesive associated with the ormocer-based and methacrylate-based flowable composite showed promising clinical performance after 24 months. However, the heavy-flow restorations showed significantly more failures. (Quintessence Int 2023;54:186-199; doi: 10.3290/j.qi.b3631841).