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Objective : To three-dimensionally evaluate the upper airway of individuals with cleft lip and palate (CLP) and Class III malocclusion and the occurrence of obstructive sleep apnea (OSA). Methods : Twenty-one CLP individuals with Class III malocclusion, 20-29 years of age, who underwent computed tomography for orthognathic surgery planning, were prospectively evaluated. All participants underwent polysomnography, and the apnea-hypopnea index ≥ 5 events/hour was considered indicative of OSA. The total upper airway and its subdivisions volumes, as well as the minimum pharyngeal cross-sectional area (CSA), were assessed using Mimics software. Results : Among the 21 individuals analyzed, 6 (29%) presented with OSA. The total upper airway and the oropharynx mean volumes were significantly decreased in subjects with OSA when compared to individuals without OSA. Mean CSA was not statistically different between groups. Conclusion : CLP individuals with Class III malocclusion and OSA have an upper airway significantly smaller than individuals without OSA.

Objective: To evaluate the occurrence of cervical vertebrae anomalies (CVA) in patients with unilateral (UCLP) and bilateral cleft lip and palate (BCLP) using cone beam computed tomography (CBCT) examinations., Design: Retrospective assessment of CBCT images. Descriptive statistics were calculated. Fisher exact test or χ 2 test was performed to evaluate the differences among each CVA between sex and type of cleft., Setting: School of Dentistry., Participants: One hundred fifty-one patients with cleft lip and palate (103 UCLP/48 BCLP)., Interventions: No relevant intervention., Main Outcome Measures: Cone beam computed tomography images were assessed for the presence or absence of 12 most commonly observed CVA: spina bifida, dehiscence, cleft of the posterior arch, cleft of the anterior arch, fusion between cervical vertebrae, block fusion, occipitalization, narrowing of the intervertebral space, posterior ponticle, os odontoideum , ossiculum terminale , and subdental cartilaginous remnants., Results: The presence of subdental cartilaginous remnants was the most frequently observed alteration-found in 81.45% of the sample-and it was the only CVA with statistically significant frequencies in the individuals with BCLP. Considering only the other CVA, 22.51% presented 1 and 5.29% presented 2 or more CVA., Conclusions: Patients with cleft lip and palate may present an overall high incidence of CVAs. However, when comparing the distribution of the CVAs among sex and types of cleft, the only significant difference noted was a higher incidence of subdental cartilaginous remnants among patients with BCLP.

Antitumor property of Crotoxin (CTX), the major toxin from Crotalus durissus terrificus snake venom, has been demonstrated in experimental animal models and clinical trials. However, the direct action of this toxin on the significant events involved in neovascularization, which are essential for tumor growth and survival, has not been confirmed. This study investigated the effects of CTX on the key parameters of neovascularization in two- and three-dimensional culture models. Murine endothelial cell lines derived from thymus hemangioma (t.End.1) were treated at different concentrations of CTX (6.25-200 nM). Endothelial cell proliferation, cell adhesion, and actin cytoskeletal dynamics on laminin (10 µg/ml), type I collagen (10 µg/ml), and fibronectin (3 µg/ml) were evaluated along with the endothelial cell migration and formation of capillary-like tubes in 3D Matrigel. CTX concentration of 50 nM inhibited tube formation on 3D Matrigel and impaired cell adhesion, proliferation, and migration under both culture medium and tumor-conditioned medium. These actions were not accountable for the loss of cell viability. Inhibition of cell adhesion to different extracellular matrix components was related to the reduction of αv and α2 integrin distribution and cytoskeletal actin polymerization (F-actin), accompanied by inhibition of focal adhesion kinase (FAK), Rac1 (GTPase) signaling proteins, and actin-related protein 2/3 (Arp 2/3) complex. This study proved that CTX inhibits the major events involved in angiogenesis, particularly against tumor stimuli, highlighting the importance of the anti-angiogenic action of CTX in inhibition of tumor progression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Kato, Pimenta, Almeida, Zambelli, Santos and Sampaio.)

Background: Melanoma is the most aggressive skin cancer, and BRAF (V600E) is the most frequent mutation that led to the development of BRAF inhibitors (BRAFi). However, patients treated with BRAFi usually present recidivism after 6-9 months. Curcumin is a turmeric substance, and it has been deeply investigated due to its anti-inflammatory and antitumoral effects. Still, the low bioavailability and biodisponibility encouraged the investigation of different analogs. DM-1 is a curcumin analog and has shown an antitumoral impact in previous studies., Methods: Evaluated DM-1 stability and cytotoxic effects for BRAFi-sensitive and resistant melanomas, as well as the role in the metalloproteinases modulation., Results: DM-1 showed growth inhibitory potential for melanoma cells, demonstrated by reduction of colony formation, migration and endothelial tube formation, and cell cycle arrest. Subtoxic doses were able to downregulate important Metalloproteinases (MMPs) related to invasiveness, such as MMP-1, -2 and -9. Negative modulations of TIMP-2 and MMP-14 reduced MMP-2 and -9 activity; however, the reverse effect is seen when increased TIMP-2 and MMP-14 resulted in raised MMP-2., Conclusion: These findings provide essential details into the functional role of DM-1 in melanomas, encouraging further studies in the development of combinatorial treatments for melanomas., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: The morbidity and mortality associated with the Marfan Syndrome (MFS) warrant timely diagnosis and intervention that can improve long-term prognosis. The aim of this study was to test the hypothesis that a distinct craniofacial morphology exists for patients with MFS that can be described quantitatively and qualitatively., Methods: Subjects with a positive diagnosis of MFS were recruited for this study (N = 36). Craniofacial anthropometric measurements were made on each subject and compared to established norms of age- and sex-matched controls using z-scores calculated for measurements of MFS patients. Lateral and frontal photographs were obtained to make qualitative assessments and describe facial features of subjects, and a clinical examination was completed to document occlusal relationships., Results: The subjects were primarily female (58%) ranging in age between 4 and 57 years (mean age 10.7 ± 6.0 years). Comparison of craniofacial measurements revealed that for 10 of the 12 measurements, ≥65% of the study population had a z-score of ± 2 and fell within the normal range for facial dimension. For 2 of the 12 measurements, over half of the subjects fell outside of the normal range (z-score < -2 or > 2) for facial dimension. Specifically, the majority of participants resided in the supernormal category for biocular width and the subnormal category for width of the face. Photographic assessment revealed retrognathia (54%) and down-slanting palpebral fissures (62%) were most prevalent in MFS patients., Conclusion: Our data suggest there are quantitative differences in the facial morphology of patients with MFS when compared to a control population., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

An early childhood carie (ECC) is an extremely destructive form of tooth decay. The aim of this study was to investigate the action of ozone (O3), and the association of sodium fluoride (NaF) with chlorhexidine (CHX) on bacteria related to ECC. Overnight culture of the bacteria was performed. On exponential phase the suspension was adjusted (101-108 CFU/mL). A drop (10μL) of each concentration of bacteria was applied on sheep blood agar plates and treated with O3 (2, 20, 200, and 2,000 ppm); after 18 hours, recovery analysis of CFU verified the reduction of bacterial activity. For NaF-CHX, sterile 96-well plates were prepared and divided into groups: G1 (150 µL TSB); G2 (20 µL of bacteria + 25 µL CHX + 25 µL NaF); and G3 (150 µL TSB + 20 µL of bacteria + 50 µL water). The plates were verified by analysis of the optical density (0, 12, 14, 16, and 18 hours). The data from O3 test were submitted to ANOVA and Tukey's test (p < 0.05). For the data from NaF-CHX, the ANOVA 2-way and Bonferroni's test (p < 0.05) were used. The number of CFU/mL showed death > 3log10 (99.9%) for all bacteria (ozone ≥ 20ppm), while the combination of NaF-CHX was more effective (p < 0.001) compared to each substance tested alone and the control group. The antimicrobial agents tested were able to inhibit all bacteria tested; O3 seemed to be a good alternative for controlling progression of carious lesions, while the association of NaF-CHX showed to be a good antimicrobial with easy and inexpensive application.

Background: The aesthetic aspects of the cleft lip nasal deformity have been appreciated for over a century, but the functional implications have remained largely underappreciated or misunderstood. This study describes the frequency and severity of nasal obstructive symptoms among children with cleft lip and/or cleft palate, addressing the hypotheses that age, cleft type, and severity are associated with the development of nasal obstructive symptoms., Methods: Children with nonsyndromic cleft lip and/or cleft palate and a comparison group of unaffected children born from 1997 to 2003 were identified through the North Carolina Birth Defects Monitoring Program and birth certificates. Nasal airway obstruction was measured using the validated Nasal Obstruction Symptom Evaluation scale., Results: The survey was completed by parental proxy for 176 children with cleft lip and/or cleft palate and 333 unaffected children. Nasal obstructive symptoms were more frequently reported in cleft lip with cleft palate compared with unaffected children (p < 0.0001); children who had isolated cleft lip with or without alveolus and isolated cleft palate were not statistically different from unaffected children. Patients with unilateral cleft lip with cleft palate were found to be more severely affected than bilateral cases. Nasal obstruction was observed in early childhood, although severity worsened in adolescence., Conclusions: This population-based study reports a high prevalence of nasal obstructive symptoms in children with cleft lip and/or cleft palate based on type and severity of the cleft. The authors encourage cleft teams to consider using this or similar screening methods to identify which children may benefit from functional rhinoplasty., Clinical Question/level of Evidence: Risk, I.

The aim of this study was to propose a classification for unilateral cleft lip and palate (UCLP) malformations based on cone beam computed tomography (CBCT) images, as well as to estimate the amount of bone necessary for grafting, and to evaluate the relationship of this volume with scores obtained using the classification. CBCT images of 33 subjects with UCLP were evaluated according to gap, arch, nasal, and dental parameters (GAND classification). Additionally, these defects were segmented and the amount of graft needed for alveolar bone grafting was estimated. The reproducibility of GAND classification was analyzed by weighted kappa test. The association of volume assessment with the classification (gap and nasal parameters) was verified using analysis of variance, while the intra-observer agreement was analyzed using the intra-class correlation coefficient. The intra-observer reproducibility of the classification ranged from 0.29 to 0.92 and the inter-observer agreement ranged from 0.29 to 0.91. There were no statistically significant values when evaluating the association of the volume with the classification (P>0.05). The GAND classification is a novel system that allows the quick estimation of the extent and complexity of the cleft. It is not possible to estimate the amount of bone needed for alveolar bone grafting based on the classification; individualized surgical planning should be done for each patient specifically., (Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Objective: to assessed the prevalence of diabetes mellitus (DM) and drug abuse in mothers of children with orofacial clefts (OFC)., Methods: 325 women who had children (0-3y) with clefts were interviewed. Data regarding type of diabetes, use of legal/illegal drugs during pregnancy, waist girth and fasting blood sugar at the first prenatal consult were collected., Results: twenty seven percent of the women had DM, out of these, 89% had gestational DM, 5,5% type 1 DM and 5,5% type 2 DM. The prevalence of DM in mothers of children with OFC was 27%, it is significantly higher than the average Brazilian population which is 7.6% (p<0.01) (OR=4.5, 95%CI=3.5-5.8). Regarding drug abuse during pregnancy, 32% of the mothers used drugs and a significant positive correlation was observed between drug abuse and the occurrence of clefts and other craniofacial anomalies (p=0.028) (OR=2.87; 95%CI=1.1-7.4)., Conclusions: DM and drug abuse during pregnancy increases the risk for OFC and related anomalies and early diagnosis of DM and prevention of drug abuse, especially in pregnant women, should be emphasized.

Objectives/hypothesis: Children with cleft lip and palate (CLP) often suffer from nasal obstruction that may be related to effects on nasal volume. The objective of this study was to compare side:side volume ratios and nasal volume in patients with unilateral (UCLP) and bilateral (BCLP) clefts with age-matched controls., Study Design: Retrospective case-control study using three-dimensional (3D) nasal airway reconstructions., Methods: We analyzed 20 subjects (age range = 7-12 years) with UCLP and BCLP from a regional craniofacial center who underwent cone beam computed tomography (CT) prior to alveolar grafting. Ten multislice CT images from age-matched controls were also analyzed. Mimics software (Materialise, Plymouth, MI) was used to create 3D reconstructions of the main nasal cavity and compute total and side-specific nasal volumes. Subjects imaged during active nasal cycling phases were excluded., Results: There was no statistically significant difference in affected:unaffected side volume ratios in UCLP (P = .48) or left:right ratios in BCLP (P = .25) when compared to left:right ratios in controls. Mean overall nasal volumes were 9,932 ± 1,807, 7,097 ± 2,596, and 6,715 ± 2,115 mm(3) for control, UCLP, and BCLP patients, respectively, with statistically significant volume decreases for both UCLP and BCLP subjects from controls (P < .05)., Conclusions: This is the first study to analyze total nasal volumes in BCLP patients. Overall nasal volume is compromised in UCLP and BCLP by approximately 30%. Additionally, our finding of no major difference in side:side ratios in UCLP and BCLP compared to controls conflicts with pre-existing literature, likely due to exclusion of actively cycling scans and our measurement of the functional nasal cavity., Level of Evidence: 3b. Laryngoscope, 126:1475-1480, 2016., (© 2015 The American Laryngological, Rhinological and Otological Society, Inc.)

The purpose of this study was to perform a microcomputed tomographic evaluation of the radioprotective effect of resveratrol on the volume of mandibular incisors of irradiated rats. A second aim was to make a quantitative assessment of the effect of x-ray exposure on these dental tissues. Twenty adult male rats were divided into four groups: control, irradiated control, resveratrol, and irradiated resveratrol. The resveratrol groups received 100 mg/kg of resveratrol, whereas the irradiated groups were exposed to 15 Gy of irradiation. The animals were sacrificed 30 days after the irradiation procedure, and their mandibles were removed and scanned in a microcomputed tomography unit. The images were loaded into Mimics software to allow segmentation of the mandibular incisor and assessment of its volume. The results were compared by One-way ANOVA and Tukey's post hoc test, considering a 5% significance level. The irradiated groups showed significantly diminished volumes of the evaluated teeth, as compared with the control group (p < 0.05). The resveratrol group presented higher values than those of the irradiated groups, and volumes similar to those of the control group. High radiation doses significantly affected tooth formation, resulting in alterations in the dental structure, and thus lower volumes. Moreover, resveratrol showed no effective radioprotective impact on dental tissues. Future studies are needed to evaluate different concentrations of this substance, in an endeavor to verify its potential as a radioprotector for these dental tissues.

Objectives: This study aimed to evaluate the accuracy of three different methods for assessing the volume of cleft defects in CBCT images. The influence of field of view (FOV) and voxel sizes was also assessed., Methods: Using three radio-opaque plastic skulls, unilateral defects were created to mimic alveolar clefts and were filled with wax following the contralateral side contours. They were scanned in a CBCT unit using four different acquisition protocols, varying FOV and voxel sizes. Using three different methods, the defect/wax volume was evaluated on the images by defining: (1) the width, height and facial-palatal length of the defect in maximum intensity projection; (2) the areas of the defect on axial slices; and (3) the threshold and segmentation of the region of interest. The values obtained from each method using different acquisition protocols were compared with the real volume of the wax (gold standard) using ANOVA and Tukey's test., Results: Methods 2 and 3 did not differ from the gold standard (p > 0.05). Conversely, Method 1 presented statistically significant overestimated values (p < 0.01). No differences were found among the different FOV and voxel sizes (p > 0.05)., Conclusions: CBCT volumes proved reliable for the volumetric assessment of alveolar cleft defects, when using Methods 2 and 3 regardless of FOV and voxel sizes. It may be possible to improve surgical planning and outcomes by knowing the exact volume of grafting material needed prior to the surgical intervention.

Background: Epidemiologic studies involving birth defects are extremely sensitive to phenotype accuracy and precision. We devised a case review and classification protocol for a project to study school achievement in children with idiopathic, nonsyndromic orofacial clefts to improve the reliability of phenotypic classification from the statewide birth defects registry., Methods: Surveillance-program abstraction data and medical records at the birth or treating hospitals were used when available. Exclusion criteria included: median cleft lip; Tessier cleft; premaxillary agenesis; presence of a recognizable syndrome, phenotype, association, or sequence (other than Robin sequence); clefts with other malformations not considered to be normal or common variants in the newborn; and cases with documented or suspected genetic or teratogenic causes., Results: Of 712 children identified with orofacial clefts, 153 were excluded, leaving 559 nonsyndromic orofacial cleft cases of unknown cause in the final study. These cases were grouped into the following clinically meaningful types: cleft lip with or without cleft alveolus; cleft lip and cleft palate; and cleft palate only. This review and classification process resulted in the elimination of 21.5% of the original cohort of identified cases, with most exclusions being due to suspected syndromic associations., Conclusion: Verbatim descriptions of the clinical findings are critical for accurate classification of diagnoses. This review process improved the precision of orofacial cleft phenotype classification for our study. Precision would have been further improved if all of the cases had verbatim descriptions of diagnoses and all medical records could have been reviewed by the classification team., (© 2015 Wiley Periodicals, Inc.)

Objectives/hypothesis: The aim of this study was to compare the volume of nasopharyngeal airways of patients with unilateral cleft lip and palate (UCLP) with a control (noncleft) group of subjects., Study Design: Retrospective case-control study., Methods: The sample consisted of 45 subjects, 30 with UCLP who underwent cone beam computed tomography (CBCT) exams as part of their workups for alveolar bone graft and 15 noncleft subjects seeking orthodontic care who obtained CBCT for diagnostic purposes. The three-dimensional volumes of nasal (NV) and oropharyngeal (PV) airways of these subjects were assessed separately using Mimics software by one well-calibrated evaluator. The images were rendered, and the volumes were measured in cm(3)., Results: The mean PV of the UCLP subjects was 6.7 cm(3) and the mean NV was 10.3 cm(3). The control group presented with a mean PV of 8.1 cm(3) and a mean NV of 11.6 cm(3). Student t test showed no statistically significant difference for PV (P = 0.10) or NV (P = 0.23) when comparing cleft and noncleft subjects., Conclusion: Evaluation of the nasopharyngeal airways revealed that the NV and PV airways showed no difference between the cleft and noncleft subjects. It is interesting to postulate that the reported nasal abnormalities of the cleft patients do not produce a significant measurable effect on the overall volume, at least as shown in our study sample. In addition, the nasopharyngeal airways of patients are not larger than those of age-matched controls, at least at the ages that were sampled, after cleft palate repair., (© 2014 The American Laryngological, Rhinological and Otological Society, Inc.)

Background and Objective: Sinus disease is noted to be common in patients with cleft lip and palate. Many have wondered if anatomic differences are a cause or at least a contributor of this. In this sense, comparisons of sinus volumes of patients with different craniofacial clefts may be helpful to determine possible differences from normal. Thus, the present study aimed to evaluate and compare the maxillary sinus volume of patients with unilateral (UCLP) and bilateral (BCLP) cleft lip and palate to control, i.e. non-cleft patients, using cone beam computed tomography (CBCT) images., Methods: The sample consisted of 30 subjects with UCLP, 15 with BCLP and 15 control individuals (non-cleft). Each maxillary sinus was assessed three-dimensionally, segmented and its volume was calculated. The comparison between right and left sinus was performed by Student t-test, and the differences between the control and cleft groups were calculated using ANOVA., Results: No statistical differences were found when the sides were compared (p>0.05). In relation to the assessment among groups, all comparisons had statistically significant differences (p<0.05), with the UCLP group presenting the lowest sinus volume., Conclusion: UCLP individuals present maxillary sinuses with smaller volumes, without differences found between the cleft and non-cleft side. BCLP subjects also present a reduction in the volume when compared to a control sample, but the average sinus volume is larger than in UCLP patients., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

This article evaluates a pH-cycling model for simulation of caries-affected and caries-infected dentin (CAD and CID, respectively) surfaces, by comparing the bond strength of an etch-and-rinse and a self-etch adhesive system. For both adhesives, bonding to sound dentin (SD) showed that the microtensile bond strength (μTBS) values of SD, CAD, and CID were SD > CAD > CID (P < 0.05). Knoop microhardness number mean values followed the same trend. Adhesive systems were not able to totally penetrate into CAD and CID, forming more irregular resin-dentin interdiffusion zones and atypical resin tags than SD. The tested in vitro pH-cycling caries model allowed the evaluation of specific dentin substrate alterations in response to μTBS. The type of dentin and its histological structure played an important role in etch-and-rinse and self-etch bonding, as lower μTBS values were attained in CAD and CID.

Craniofacial microsomia (CFM) is a complex condition associated with microtia, mandibular hypoplasia, and preauricular tags. It is the second most common congenital facial condition treated in many craniofacial centers and requires longitudinal multidisciplinary patient care. The purpose of this article is to summarize current recommendations for clinical management and discuss opportunities to advance clinical research in CFM., (© 2013 Wiley Periodicals, Inc.)

The skull of young children is made up of bony plates that enable growth. Craniosynostosis is a birth defect that causes one or more sutures on an infant's skull to close prematurely. Corrective surgery focuses on cranial and orbital rim shaping to return the skull to a more normal shape. Functional problems caused by craniosynostosis such as speech and motor delay can improve after surgical correction, but a post-surgical analysis of brain development in comparison with age-matched healthy controls is necessary to assess surgical outcome. Full brain segmentations obtained from pre- and post-operative computed tomography (CT) scans of 8 patients with single suture sagittal (n=5) and metopic (n=3), non-syndromic craniosynostosis from 41 to 452 days-of-age were included in this study. Age-matched controls obtained via 4D acceleration-based regression of a cohort of 402 full brain segmentations from healthy controls magnetic resonance images (MRI) were also used for comparison (ages 38 to 825 days). 3D point-based models of patient and control cohorts were obtained using SPHARM-PDM shape analysis tool. From a full dataset of regressed shapes, 240 healthy regressed shapes between 30 and 588 days-of-age (time step = 2.34 days) were selected. Volumes and shape metrics were obtained for craniosynostosis and healthy age-matched subjects. Volumes and shape metrics in single suture craniosynostosis patients were larger than age-matched controls for pre- and post-surgery. The use of 3D shape and volumetric measurements show that brain growth is not normal in patients with single suture craniosynostosis.

Background: Craniofacial microsomia (CFM) is a congenital condition characterized by microtia and mandibular underdevelopment. Healthcare databases and birth defects surveillance programs could be used to improve knowledge of CFM. However, no specific International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code exists for this condition, which makes standardized data collection challenging. Our aim was to evaluate the validity of existing ICD-9-CM codes to identify individuals with CFM., Methods: Study sample eligibility criteria were developed by an expert panel and matched to 11 ICD-9-CM codes. We queried hospital discharge data from two craniofacial centers and identified a total of 12,254 individuals who had ≥1 potentially CFM-related code(s). We reviewed all (n = 799) medical records identified at the University of North Carolina (UNC) and 500 randomly selected records at Seattle Children's Hospital (SCH). Individuals were classified as a CFM case or non-case., Results: Thirty-two individuals (6%) at SCH and 93 (12%) at UNC met the CFM eligibility criteria. At both centers, 59% of cases and 95% of non-cases had only one code assigned. At both centers, the most frequent codes were 744.23 (microtia), 754.0 and 756.0 (nonspecific codes), and the code 744.23 had a positive predictive value (PPV) >80% and sensitivity >70%. The code 754.0 had a sensitivity of 3% (PPV <1%) at SCH and 36% (PPV = 5%) at UNC, whereas 756.0 had a sensitivity of 38% (PPV = 5%) at SCH and 18% (PPV = 26%) at UNC., Conclusions: These findings suggest the need for a specific CFM code to facilitate CFM surveillance and research., (Copyright © 2012 Wiley Periodicals, Inc.)

Craniofacial microsomia (CFM) is a congenital condition associated with orbital, mandibular, ear, nerve, and soft tissue anomalies. We present a standardized, two-dimensional, digital photographic protocol designed to capture the common craniofacial features associated with CFM., (© 2011 Heike et al; licensee BioMed Central Ltd.)

Odontogenic myxomas (OMs) are nonencapsulated rare benign tumors that can occur in gnathic bones. They are locally invasive and have a high recurrence rate. Radiologically, OMs show a multilocular (in the majority of cases) or unilocular radiolucency, with either distinct or poorly defined margins. Histopathologically, OMs are characterized by spindle-, wedge-, or stellate-shaped cells loosely arranged in an abundant mucoid background. Myxomas are mainly asymptomatic. Radical surgery, excision, and enucleation followed by curettage of the surrounding bony tissue have all been advocated as treatment options. This study presents a successful case of conservative treatment of OMs with a 5-year follow-up.

Neuromuscular electrical stimulation (NMES) can alter the functioning of muscles and even assist muscle rehabilitation. In this paper, we evaluate the effect of NMES on the conduction velocity (CV) of the brachial biceps' motor units. We used a linear array of electrodes to acquire electromyographic signals, as different subjects perform isometric voluntary contractions (IVCs), with and without prior NMES. Our results show that, after NMES, the CVs at the beginning of the IVCs tend to increase, with respect to the case without NMES. Also, we observed that, while in the absence of NMES, the CVs tend to decrease over time with continued IVCs, this does not happen after 20 minutes of NMES, and the CVs can, in some cases, increase with the contractions.

Purpose: This study evaluated the effect of the use of different finishing instruments on the marginal integrity of resin composite restorations., Materials and Methods: Bovine incisors (N = 75) embedded in epoxy resin had the facial enamel ground and polished to 1200-grit. A standardized cavity (3 x 3 mm, 2 mm deep) was prepared on each specimen and restored with a 2-step total-etch adhesive (Single Bond, 3M ESPE, St. Paul, MN, USA) and a hybrid resin composite (Filtek Z250, 3M ESPE) in a single increment. The restorations were mechanically polished to 1200-grit. Specimens were randomized into different groups (N = 5) according to finishing technique: positive control (1200-grit paper), negative control (regular-grit diamond), fine cross-cut laminated burs, straight-cut laminated burs, spiral-cut laminated burs, and finishing diamonds. The straight-cut burs, spiral-cut burs, and finishing diamonds were tested individually as fine, extra-fine, and ultra-fine, as well as sequentially as a series. A high-speed, water-cooled handpiece under standardized pressure (0.5 N) and time (40 seconds) was used for all finishing procedures. Specimens were processed for scanning electron microscope, and margin gaps were systematically measured. Data were analyzed with one-way analysis of variance and Duncan test., Results: The negative control specimens (course diamond) presented the largest gaps, whereas the positive control specimens (mechanically polished) generated the smallest gaps. No statistically significant difference was noted between the finishing diamonds and the positive control. The negative control exhibited significantly larger gaps when compared with the other finishing instruments. Intermediate results were observed for cross-cut, straight-cut, and spiral-cut laminated burs. Fine, extra-fine and ultra-fine finishing diamonds generated smaller gaps compared with laminated burs, but the differences were not always statistically significant., Conclusion: Fine, extra-fine and ultra-fine finishing diamonds used to finish composite restorations generated better marginal integrity when compared with carbides and regular-grit diamonds. CLINICAL SIGNIFICANCE When finishing composite restorations, finishing diamond burs result in better composite margins than carbide laminated burs.

The aim of this study was to compare different treatments for dentin hypersensitivity in a 6-month follow-up. One hundred and one teeth exhibiting non carious cervical lesions were selected. The assessment method used to quantify sensitivity was the cold air syringe, recorded by the visual analogue scale (VAS), prior to treatment (baseline), immediately after topical treatment, after 1 week, 1, 3 and 6 months. Teeth were randomly assigned to five groups (n = 20): G1: Gluma Desensitizer (GD); G2: Seal& (SP); G3: Oxa-gel (OG); G4: Fluoride (F); G5: Low intensity laser-LILT (660 nm/3.8 J/cm(2)/15 mW). Analysis was based on the non-parametric Kruskal-Wallis test that demonstrated statistical differences immediately after the treatment (p = 0.0165). To observe the individual effects of each treatment, data was submitted to Friedman test. It was observed that GD and SP showed immediate effect after application. Reduction in the pain level throughout the six-month follow-up was also observed. In contrast, LILT presented a gradual reduction of hypersensitivity. OG and F showed effects as of the first and third month respectively. It can be concluded that, after the 6-month clinical evaluation, all therapies showed lower VAS sensitivity values compared with baseline, independently of their different modes of action.

Aim: The purpose of this study was to evaluate if Knoop hardness values (KHN) for top and bottom surfaces of resin composite materials can reach a plateau within a clinically acceptable photoactivation time., Methods and Materials: Four light-curing units (LCUs) were evaluated in this study (n=5): QTH (Optilux501: 550 mW/cm2) and LEDs (FreeLight2: 1100 mW/cm2; UltraLume5: 900 mW/cm2; and Radii: 750 mW/cm2). Composite resin discs (4 mm x 2 mm) of Heliomolar (Ivoclar/Vivadent) and Herculite XRV (Kerr) were tested using five photoactivation times (20, 40, 60, 80, and 100 seconds). KHN were obtained for each test specimen and comparisons between LCUs, depths, and photoactivation times were analyzed using two-way analysis of variance (ANOVA) and polynomial regression analysis., Results: Data for Heliomolar discs using linear regression found a relationship between the independent variables KHN and time with the Optilux501 at the top and bottom surfaces (r2=0.68/ r2=0.66). Radii presented a linear regression at the top surface (r2=0.75) and a quadratic regression at the bottom (r2=0.94). A quadratic regression was also detected for UltraLume5 and FreeLight2 at both top (r2=0.84/ r2=0.94) and bottom surfaces (r2=0.97/ r2=0.90), respectively, reaching a plateau at 80 seconds in all cases. For Herculite XRV, a quadratic regression was observed for all LCUs at the top and bottom surfaces and 80 seconds irradiation time was needed to reach a plateau in KHN., Conclusion: There is a specific, but not clinically acceptable, photoactivation time that KHN at both top and bottom surfaces can reach a plateau and is dependent on LCUs and the resin-composite tested., Clinical Significance: The LCUs and the resin-composite formulation affected the exposure time required to stabilize hardness values. The overall performance of LED LCUs was better than the QTH LCU regardless of the material evaluated.

Purpose: To investigate the effect of filler-particle size of experimental and commercial resin composites, undergoing toothbrush abrasion, on three surface properties: surface roughness (SR), surface gloss (G) and color stability (CS)., Methods: Four model (Ivoclar/Vivadent) and one commercial resin composite (Tokuyama) with varying filler-size from 100-1000 nm were examined. Six discs (10 mm x 2 mm) from each product were prepared and mechanically polished. The samples were then submitted to 20,000 brushing strokes in a toothbrush abrasion machine. SR parameters (Ra, Rt and RSm), G, and CS were measured before and after toothbrush abrasion. Changes in SR and G were analyzed by 2-way ANOVA, with Bonferroni post hoc test. CS values were submitted to one-way ANOVA and Bonferroni post hoc test (alpha=0.05)., Results: Initial G values ranged between 73-87 gloss units (GU) and were reduced after toothbrush abrasion to a range of 8-64 GU. Toothbrush abrasion resulted in significant modifications in SR and G amongst the materials tested, attributed to filler sizes. There was statistically significant difference in color (delta E* ranged from 0.38-0.88). Filler size did not affect color stability. Toothbrush abrasion resulted in rougher and matte surfaces for all materials tested. Although the individual differences in surface roughness among filler sizes were not always significant, the correlation showed a trend that larger filler sizes resulted in higher surface roughness after abrasion for the SR parameters Ra and Rt (r = 0.95; r = 0.93, respectively). RSm showed an increase after toothbrush abrasion for all resin composites, however no significant correlation was detected (r = 0.21).There was a significant correlation between G and Ra ratios (r = - 0.95).

Objective: The purpose of this in vitro study was to evaluate and compare dentin and enamel bond strengths obtained with dual-cure composite luting agents when used with dual-cure dental adhesives., Methods: Human molars were ground flat to expose enamel (n=80) or dentin (n=80). Specimens in each substrate group were randomly assigned to eight treatment sub-groups, according to four adhesive-luting agent combinations and two test conditions (with or without thermocycling). Pre-polymerized composite resin posts (TPH Spectrum) were luted to either the enamel or dentin surfaces with one of the following adhesive-luting agent combinations: (1) Xeno IV Dual Cure (dual-cure self-etch adhesive) and Calibra (dual-cure luting agent); (2) Prime & Bond NT Dual Cure (dual-cure total-etch adhesive) and Calibra; (3) OptiBond All-in-One Dual Cure (dual-cure self-etch adhesive) and Nexus 2 Dual Syringe (dual-cure luting agent); (4) OptiBond Solo Plus Dual Cure (dual-cure total-etch adhesive) and Nexus 2 Dual Syringe. For each treatment sub-group, half the specimens (n=10) were tested after 24h storage in water at 37 degrees C, and the other half (n=10) were tested after thermocycling for 1800 cycles between water baths held at 5 and 55 degrees C, with a dwell time in each bath of 30s, and a transfer time of 10s. Bond strengths were measured in shear mode, and expressed in MPa. The fracture mode (adhesive, cohesive, mixed) was examined. Data were analyzed for statistical significance with a factorial ANOVA and post hoc tests., Results: Mean enamel bond strengths ranged from 8.4MPa for non-thermocycled OptiBond All-in-One|Nexus 2 to 35.5MPa for non-thermocycled Prime & Bond NT|Calibra. Mean dentin bond strengths ranged from 14.5MPa for non-thermocycled OptiBond Solo Plus|Nexus 2 to 30.9MPa for thermocycled Xeno IV|Calibra. The fracture mode was predominantly adhesive for all groups., Conclusions: On enamel, the total-etch adhesives performed better than their self-etch counterparts, while in dentin, the opposite was found, i.e., the self-etch adhesives performed better than their total-etch counterparts. Thermocycling for 1800 cycles did not affect the SBS of the materials tested to dentin and enamel.

This in vitro study aimed to evaluate a pH-cycling model for simulation of caries-affected dentin (CAD) surfaces, by comparing the bond strength of etch-and-rinse adhesive systems on sound and artificially-created CAD. Dentin substrates with different mineral contents and morphological patterns were created by submitting buccal bovine dentin to the following treatments: (1) immersion in artificial saliva during the experimental period (sound dentin, SD), or (2) induction to a CAD condition by means of a dynamic pH-cycling model (8 cycles, demineralization for 3 h followed by mineralization for 45 h). The bond strength of Excite or Prime and Bond NT adhesive systems was assessed using the microtensile bond strength (microTBS) test. Dentin microhardness was determined by cross-sectional Knoop evaluations. Resin-dentin morphology after the treatments was examined by scanning electron microscopy. SD produced significantly higher microTBS than CAD for both adhesives evaluated, without differences between materials. CAD exhibited lower microhardness than SD. Morphological analysis showed marked distinctions between SD and CAD bonded interfaces. Under the conditions of this study, differences in morphological pattern and dentin mineral content may help to explain resin-dentin bond strengths. The proposed pH-cycling model may be a suitable method to simulate CAD surfaces for bonding evaluations., (2007 Wiley Periodicals, Inc.)

Objectives: To evaluate the longevity of sound (SD) and caries-affected dentin (CAD) bonds made with etch-and-rinse and self-etching adhesives after a 6-month water-storage period, using bond strength and morphological evaluations., Methods: Extracted human molars with coronal carious lesions were selected. Flat surfaces of CAD surrounded by SD were bonded with etch-and-rinse (Adper Scotchbond 1) or with self-etching (Clearfil Protect Bond and AdheSE) adhesives. Trimmed resin-dentin bonded interfaces (1mm2) were stored in distilled water for 24h or 6 months and subjected to microtensile bond strength (microTBS) evaluation. The quality of the dentin beneath fractured specimens was measured by Knoop microhardness (KHN). ANOVA and multiple comparisons tests were used (P<0.05). Fractographic analysis and interfacial nanoleakage evaluation were performed by scanning electron microscopy (SEM). Resin-dentin bonded sections (10microm thick) were stained with Masson's trichrome and examined using light microscopy. Collagen exposure and adhesive penetration were examined qualitatively., Results: microTBS to SD was significantly higher than that to CAD for all bonding agents. Bonds made with AdheSE were weaker than the other adhesives after 6-months storage regardless of the dentin substrate. CAD bonded specimens presented a significant muTBS decrease over time. Lower KHN was recorded in CAD compared to SD. An increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration were observed in CAD interfaces., Significance: CAD bonded interfaces are more prone to hydrolytic degradation than SD bonds. Additionally, as compared to SD, there were remarkable differences in depth of demineralization, adhesive infiltration and interfacial bond strength with CAD.

This study sought to evaluate the long-term bond strength of etch-and-rinse and self-etch adhesive systems to dentin after one year of water storage. Crown fragments from the buccal surface of extracted bovine incisors were ground flat to expose dentin surfaces. Four etch-and-rinse and two self-etch bonding agents were used according to manufacturers' instructions. Bonded specimens were stored in water for either 24 hours or one year at 37 delete C. After elapsed storage times, specimens were tested for shear bond strength (SBS) at 0.5 mm/min. Data were analyzed by ANOVA and Tukey's tests (p < 0.05). Both evaluated factors (adhesive system and storage time) and their interactions were statistically significant. Single Bond produced the highest SBS regardless of the water degradation period. One-year water storage reduced the SBS of Prime & Bond NT and One-Up Bond F significantly; the other adhesives performed similarly. Long-term bond strengths of etch-and-rinse and self-etch adhesive systems are susceptible to hygroscopic and hydrolytic effects to varying extents, depending on their chemistry and structure. The presence of monomers with different properties might induce preferential degradation of specific adhesive polymer systems.

Background: The Centers for Disease Control and Prevention has adopted guidelines for infection control of extracted teeth used for research and teaching, requiring that teeth be sterilized before use. The authors conducted a study to test the null hypothesis that the storage medium and sterilization method have no effect on composite-to-dentin bond strengths., Materials and Methods: The authors collected 170 bovine incisors, cleaned them and placed them randomly into one of six storage media at 37 degrees C for 60 days: distilled water (dH(2)O), 0.9 percent sodium chloride, 0.5 percent chloramine-T, 5.25 percent sodium hypochlorite (NaClO), 2 percent glutaraldehyde and 10 percent formalin. For sterilization, they autoclaved a subset of 10 specimens from every sample, while they stored another subset of 10 specimens from every sample (except for the 10 percent formalin sample) in 10 percent formalin for 14 days. The authors then embedded the specimens in epoxy and ground flat the facial surface to expose middle-depth dentin, which they polished to 600 grit. They used a dental adhesive to apply composite to the exposed dentin. The authors tested the composite-to-dentin shear bond strength 24 hours after bonding. They analyzed the data using global analysis of variance and, when appropriate, multiple post hoc tests (P = .05)., Results: Storage in NaClO resulted in significantly lower bond strength than that of the other treatment specimens. Sterilization with the autoclave negatively affected the bond strength of specimens stored initially in dH(2)O or 10 percent formalin, while sterilization with formalin alone had no significant effect on bond strengths., Conclusions: Storing bovine teeth in 5.25 percent NaClO may negatively affect composite-to-dentin bond strengths. Immersion in 10 percent formalin might be the best option for storage and sterilization of bovine teeth that are to be used in dental bonding studies in vitro.

Aims: The aim of this study was to test the influence of different curing protocols on dentin marginal adaptation and the hardness of two composites., Methods and Materials: Three light-curing-units (LCUs): Quartz-Tungsten-Halogen (QTH: 541 mW/cm2), Argon-Ion-Laser (AL: 277 mW/cm2), and Plasma-Arc-Curing (PAC: 1818 mW/cm2) and two composites FiltekZ250 (F) and Tetric Ceram HB (TC) were tested. Sixty standardized "vertical-slot-Class II-cavities" were prepared at the mesial surface of bovine incisors and divided into six groups (n=10). Composites were placed using the Single Bond adhesive system and cured in 2 mm increments according to the manufacturers' instructions. After polishing, epoxy replicas were processed for scanning electron microscopy (SEM) marginal adaptation analysis at 500x magnification. The specimens were then sectioned transversally to the dental long axis, embedded in polyester resin, then polished and submitted to the Knoop hardness test at gingival and occlusal portions of the restoration. Data were analyzed using two-way analysis of variance (ANOVA) and Tukey's test (p=0.05)., Results: The gap margins ranged between 4.3 to 5.8 microm, and no statistically significant differences were revealed in marginal adaptation for LCUs or for composites (p>0.05). Location influenced hardness (p=0.01). The occlusal portion presented significantly higher KHN than the gingival portion for all composite-LCU combinations. Regardless of the LCU used, TC produced statistically significant lower hardness values (ranging between 82.8 to 110.7 KHN) than F (ranging between 105.9 to 117.3 KHN)., Conclusions: Hardness and gap formation were not dependent on the LCUs tested in this study. Different resin composite was found to be a significant factor with regards to hardness but not gap formation.

Aim: The aim of this study was to evaluate the influence of four photoactivation systems [quartz tungsten halogen (QTH), light-emitting diode (LED), argon ion laser (AL), and plasma arc curing PAC)] on cementum/dentin and enamel microleakage of Class II restorations using a microhybrid [Z250-3M ESPE] and two packable composites [(SureFil-Dentsply and Tetric Ceram HB-Ivoclair/Vivadent]., Methods and Materials: Three hundred sixty "vertical-slot Class II cavities" were prepared at the mesial surface of bovine incisors using a 245 carbide bur in a highspeed handpiece. Specimens were divided into twelve groups (composite-photoactivation systems). Half of the specimens had the gingival margin placed in enamel (n=15) and the other half in cementum/dentin (n=15). Composites were inserted and cured in 2 mm increments according to manufacturers' recommended exposure times. After polishing, the samples were immersed in 2% methylene blue solution, sectioned, and evaluated at the gingival margins. Data were submitted to statistical analysis using the Kruskal-Wallis and Mann-Whitney tests., Results: No significant differences were found among the photoactivation systems and among resin composites (p>0.05). Microleakage was not significantly affected by location (enamel vs. cementum/dentin, p>0.05). These findings suggested neither the photoactivation systems nor the resin composite types might have an effect on the microleakage at gingival margins Class II cavities.

This pilot study evaluated the effect of removing acid-etch-exposed dentin collagen on the clinical performance of composite restorations of noncarious cervical lesions placed using 2 different adhesive systems. Fifty-six restorations were placed in 14 subjects, each subject receiving at least 4 restorations. No cavity preparation or mechanical retention form was used. The variables tested were: 1) dentin treatment prior to application of the adhesive (acid-etch only vs acid-etch and collagen removal) and 2) type of adhesive (acetone- vs ethanol-based). For the acid-etch only groups, enamel and dentin were etched with 37% phosphoric acid for 15 seconds, rinsed and blot dried. Prime & Bond 2.1 (Dentsply Caulk) or Single Bond (3M ESPE) was applied and light-cured according to the manufacturer's instructions. For the acid-etch and collagen removal groups, the enamel and dentin were etched and rinsed in the same manner and a 10% sodium hypochlorite (NaOCl) solution was applied for 60 seconds and rinsed before adhesive application. Filtek Z-250 (3M ESPE) was applied to all specimens and light-cured according to the manufacturer's instructions, and the restorations were finished and polished immediately. The restorations were evaluated for pre- and post-operative sensitivity, retention, marginal staining and secondary caries at baseline, 12 and 24 months after placement, using modified USPHS criteria. Data were analyzed using the Kruskal-Wallis and Wilcoxon statistical tests (p=0.05). At 24 months, the retention rates for Prime & Bond 2.1 with and without NaOCl pretreatment were 80% and 63%, respectively. The corresponding retention rates for Single Bond were 70% and 90%. Marginal staining was minimal. Statistical analyses revealed no significant differences at any time interval between groups for retention or marginal staining. No post-operative sensitivity or secondary caries was detected during the study.

The objective of this study was to investigate the effects of different light-curing methods on microleakage, marginal adaptation, and microhardness of composite restorations. Slot-type preparations were made in bovine teeth, with gingival margins on dentin. Specimens were divided into 12 groups (n = 12) according to composite-light-curing unit (LCU) combinations. Three composites were used: Filtek Supreme, Herculite XRV, and Heliomolar. All restorations were placed using the same adhesive. Four LCUs were used: a quartz-tungsten-halogen (QTH) LCU (Optilux 501), a first-generation light-emitting diode (LED) LCU (FreeLight 1), and two second-generation LED LCUs (FreeLight 2 and Translux Power Blue). After finishing and polishing, specimens were subjected to mechanical load cycling (100,000 cycles). Gingival margin adaptation was determined as a function of gap formation using epoxy replicas. Microleakage was evaluated by measuring dye penetration across the gingival wall in cross-sectioned specimens. Microhardness was measured as Knoop Hardness number (KHN) at different occluso-gingival locations in cross-sectioned specimens. Data were analyzed for statistical significance (p = 0.05) using appropriate statistical tests. Marginal adaptation was affected by load-cycling in most specimens, but no significant differences were observed among composites and LCUs. Microleakage was not affected by LCU, except for Heliomolar specimens which when cured with Optilux 501 resulted in higher microleakage scores than those obtained with the other LCUs. For microhardness, Translux Power Blue generally produced the highest values and the FreeLight 1 produced the lowest. The performance of the second-generation LED LCUs generally was similar to that of the QTH control, and better than that of the first-generation LED unit.

Purpose: This study was designed to analyze the influence of desensitizing procedures on dentin bond strength., Materials and Methods: Forty bovine incisors were used, divided into four groups (n = 10): G1: control; G2: Gluma Desensitizer (Heraeus Kulzer); G3: Oxa-Gel (Art-Dent); G4: low-intensity laser (MMOptics). The buccal surface was wet ground flat with 180-, 400- and 600-grit silicon carbide abrasive paper to expose midcoronal dentin and create a uniform surface. After the application of the desensitizing agents to the exposed dentin, the specimens were etched with 35% phosphoric acid for 30 s, and an adhesive (Single Bond) was applied and light cured. A 4-mm high crown of composite resin (Filtek Z250) was then built up. Specimens were trimmed to an hourglass shape with cross sections of 1 mm2. Each specimen was individually fractured by a microtensile testing machine at a crosshead speed of 0.5 mm/min. The data, recorded in MPa, were analyzed with one-way ANOVA and the Duncan test (p = 0.05)., Results: Specimens treated with dentin desensitizers (except Gluma) yielded significantly lower mean bond strengths than nontreated control specimens. The mean values in MPa (+/- SD) were: G1: 13.4 (6.2); G2: 13.2 (4.8); G3: 7.15 (4.3); G4: 7.21 (4.6)., Conclusions: Among the desensitizing agents studied, only Gluma Desensitizer did not detrimentally influence the bond strength values. It is a useful material for dentin desensitization.

This study evaluated the influence of different thermal (TC) and mechanical (MC) cycling protocols on microtensile bond strength (muTBS) to cervical dentin margins of Class II restorations using two total-etch (TE) adhesives and one self-etching (SE) primer. Class II slot cavities were prepared on the mesial surfaces of 168 bovine incisors and were divided into three groups according to the bonding system used: Single Bond, OptiBond Solo Plus and Clearfil SE Bond. All cavities were restored with Filtek Z250 composite. Following restorative procedures, the restored teeth were allocated to seven subgroups (n = 8) according to the thermal/mechanical protocol performed: G1-control (no cycling), G2-100,000 MC, G3-200,000 MC, G4-500,000 MC, G5-100,000 MC+1,000 TC, G6-200,000 MC+1,000 TC, G7-500,000 MC+1,000 TC. TC was performed using 5 +/- 2 degrees C and 55 +/- 2 degrees C baths, with a dwell time of 60 seconds in each bath. MC was achieved with an axial force of 80 N at 2 cycles/second. The restorations were sectioned perpendicular to the cervical bonded interface into two 0.8-1-mm thick slabs. The slabs were trimmed at the interface to obtain a cross-sectional surface area of 0.8-1 mm2. All specimens were then subjected to muTBS (v = 0.5 mm/minute). Fracture mode analysis was performed using SEM. Bond strength mean values (MPa) were analyzed with ANOVA 3-way and Tukey's test (alpha = 5%). Dunnett's test was used to compare tested groups against Control groups of each adhesive system (alpha = 56%). SE primer presented lower mean bond strength values when compared to TE adhesives (p = 0.05). In addition, specimens restored with the SE primer did not resist to the 200,000 and 500,000 MC associated with TC. The application of 100,000 MC did not present a significant decrease in bond strength when compared to the control. Mixed failures were predominant for all groups. The higher the amount of thermal/mechanical cycles, the greater the number of mixed failures and the lower the percentage of adhesive failures.

In natural ecosystems, micro-organisms grow preferentially attached to surfaces, forming matrix-enclosed biofilms. The aim of this study was to determine photodestruction levels in biofilms after subjecting them to photodynamic therapy. Biofilms of Streptococcus mutans, S. sobrinus, and S. sanguinis were grown on enamel slabs for 3, 5 or 7 d. Both the number of viable micro-organisms and the concentration of water-insoluble polysaccharides were analysed, and mineral loss (DeltaZ) analyses were performed on the enamel slabs. The antimicrobial potential of toluidine blue O (0.1 mg ml(-1)), associated with 85.7 J cm(-2) of a light-emission diode, was evaluated on the viability of 5-d biofilms. Both the number of micro-organisms and the concentration of water-insoluble polysaccharide increased with the age of the biofilms. A significant reduction ( approximately 95%) in viability was observed for S. mutans and S. sobrinus biofilms following photosensitization, with a > 99.9% reduction in the viability of S. sanguinis biofilms. In conclusion, a biofilm model was shown to be suitable for studying changes in bacterial numbers and enamel mineralization and for demonstrating the potential value of photosensitization in the control of in vitro biofilms.

Purpose: To investigate the behavior of two bonding systems: self-etching primer Clearfil Liner Bond 2V (CLB) and total-etch Single Bond (SB) when submitted to two bond strength tests: shear bond strength (SBS) and microtensile (MTBS)., Methods: Flat dentin surfaces were obtained at the facial surface of extracted bovine incisors. muTBS started with adhesive application and incremental resin composite insertion. Samples were then sliced into 1 mm slabs parallel to the long axis of the tooth. Half of the specimens from each group were trimmed in order to obtain dumbbell-shaped (D) specimens with a cross-sectional area of 1 mm2, and in the other half of the group, the slabs were cut into beams (B) with a cross section of 1 mm2 area. Specimens were individually fractured on a microtensile apparatus. For SBS, crown segments were embedded in polyester resin and a flat dentin surface was exposed for bonding. After adhesive and restorative procedures were accomplished, the specimens were kept in water for 24 hours prior to bond testing. The tests were performed in a universal testing machine. MPa values were analyzed by Tukey's test (P < 0.05), two-way ANOVA (muTBS) and Student's t-test (SBS)., Results: Mean values (SD) on muTBS were: SB/B: 42.6 (15.1), SB/D: 35.4 (6.8), CLB/B: 14.3 (10.3) and CLB/D: 27.0 (7.9). SBS values (SD) were: SB: 17.3 (5.6) and CLB 15.9 (7.2). Beam specimens bonded with CLB presented the lowest results. SBS did not show statistical differences between groups. The results showed that the shear bond test seemed to lack the sensitivity that is required to detect subtle differences between bonding agents or procedures.

Purpose: The purpose of this study was to evaluate the effects of different light-curing techniques on the microtensile bond strength of hybrid and packable resin composite to dentin. The null hypotheses were that different light-curing techniques do not affect the adhesion of resin composites to tooth structure and that different resin composites do not have a similar bond to dentin., Materials and Methods: One hundred four box-shaped buccal preparations were made and dentin/enamel adhesive was applied according to the manufacturer's instructions (Single Bond 3M ESPE). A hybrid resin composite (Filtek Z250, A2, 3M ESPE) or a packable resin composite (Solitaire 2, A2, Heraeus Kulzer) were inserted in bulk and polymerized using one of these techniques (n = 13): (a) Soft-start (SS) using a halogen lamp (QTH); (b) LED low intensity; (c) Plasma arc (PAC) curing for 6 s for packable resin composite and 3 s for the hybrid resin composite; (d) Conventional (C) QTH curing for 40 s. Afterwards, specimens were thermocycled 1,000 times between 5 degrees C and 55 degrees C in tap water, and were sectioned into beams with a rectangular cross-sectional area of approximately 1 mm2. Microtensile bond strength testing was performed using a universal testing machine at a crosshead speed of 0.5 mm/min., Results: Bond strength means +/- (SD) in MPa were: Filtek Z250: SSQTH = 17.9 (5.4); LED = 17.9 (6.4); PAC = 16.8 (6.8); CQTH = 16.1 (4.6). Solitaire 2: SSQTH = 12.4 (6.4); LED = 15.5 (4.3); PAC = 16.2 (4.4); CQTH = 13.8 (5.7). The data were structured in a split-plot design and analyzed by a two-way ANOVA and Tukey's tests (alpha = 0.05)., Conclusion: The light-curing method did not significantly affect bond strengths. However, the bond strengths of the packable resin composite were significantly lower than those of the hybrid resin composite for all polymerization techniques, suggesting that the restorative material itself might be a more critical factor in adhesion than the curing method.

Purpose: The purpose of this study was to investigate the surface roughness (Ra) of different esthetic restorative materials following simulated toothbrushing using different whitening dentifrices., Materials and Methods: Cylinders of Esthet-X (Dentsply Caulk, Milford, DE, USA), Durafil VS (Heraeus Kulzer, Wehrheim, Germany), and Vitremer (3M ESPE, St. Paul, MN, USA) were made using molds (4 mm in diameter for 2 mm in height). The superficial roughness was evaluated using a profilometer (Ra) with a cutoff length of 0.25 mm and a speed of 0.1 mm/s. The specimens (N=13) were submitted to 7,500 brushing cycles using five different toothpastes: (1) Crest Regular (control; Procter & Gamble): silica abrasive (C); (2) Crest Extra Whitening (Procter & Gamble, Cincinnati, OH, USA): bicarbonate+calcium pyrophosphate (CE); (3) Dental Care A & H (Arm & Hammer, Camilla, GA, USA): bicarbonate (DC); (4) Rembrandt Plus Whitening (Oral B Laboratories, Belmont, CA, USA): carbamide peroxide+alumina/silica (RP); and (5) experimental: hydrogen peroxide+calcium carbonate (EX)., Results: The data were analyzed by analysis of variance and Tukey's test (alpha=.05) for each restorative material, and the results [difference between final and initial roughness: Ra(F)-Ra(I) in microm] were as follows: Esthet-X: EX=0.15+0.07a; RP=0.29+0.16a; CE=0.96+0.33b; C=1.03+0.29b; DC=1.48+0.37b; Durafil VS: RP=0.09+0.07a; EX=0.55+0.23abc; C=0.96+0.26bc; CE=1.03+0.33cd; DC=1.09+0.37d; and Vitremer: EX=0.10+0.08a; RP=0.26+0.19a; CE=0.94+0.27b; DC=1.13+0.46bc; C=1.50+0.32c (different letters mean differences among groups)., Conclusion: It was verified that the dentifrices containing carbamide or hydrogen peroxide along with alumina+silica and calcium carbonate, respectively (groups 4 and 5), produced minor changes in Ra when compared with the control group and with those dentifrices containing bicarbonate (groups 2 and 3). CLINICAL significance The results of this study indicate that whitening dentifrices evaluated containing silica or calcium carbonate were less abrasive when used on the resin-based esthetic restorative materials than those that contain sodium bicarbonate.

Objectives: The aim of this 'in situ' study was to evaluate the microhardness of dental enamel following treatment with an in-office and an at-home vital bleaching agent through a novel approach using samples temporarily bonded 'in vivo'., Methods: Human dental enamel slabs (n=88) were subjected to sequential polishing and initial Knoop microhardness tests were performed. The slabs were fixed to the facial surfaces of the maxillary first molars of 44 human volunteers. They were divided into four groups (n=11) according to the treatment group: G1- in-office-CP37+ at-home-CP10; G2- in-office-CP37+ at-home-PLA; G3- in-office-PLA and at-home-CP10; G4- in-office and at-home-PLA. After 3 weeks of treatment, final microhardness measurements were performed., Results and Significance: ANOVA and Tukey's HSD hoc analysis (alpha=0.05) revealed no differences among initial or final microhardness values (p>0.05); however, significant differences occurred between initial and final values for each group (p<0.01), The evaluation of microhardness revealed a reduction of 6.8% for G1, 4.1% for G2, 3.4% for G3 and 3.5% for G4. In-office bleaching with 37% carbamide peroxide, an at-home bleaching with 10% carbamide peroxide, and a combination of both resulted in lower enamel microhardness when measured immediately post-treatment. However, long-term effects of these treatments are not known, and are believed to be clinically insignificant due to the relatively small reductions observed in enamel microhardness. Interestingly, the carrier, Cabopol 934P, also resulted in similar reduction in enamel microhardness even when administrated alone as a placebo.

This study evaluated the cariostatic effect of antibacterial self-etching adhesive systems, by means of an in vitro bacterial caries model. Seventy-five prepared bovine slabs were randomly divided into groups (n=15): (1) unbonded composite, no carious challenge (UNB-NC); (2) unbonded composite, carious challenge (UNB-C); (3) Clearfil SE Bond, no antibacterial agent (CSE); (4) Protect Bond, containing MDPB and fluoride (PB); and (5) Reactmer Bond, fluoride-releasing (RB). All preparations were restored with Filtek Z-250. Groups (2)-(5) were submitted to a medium containing Streptococcus mutans (ATCC-- 25175) for 5 days, and Group (1) was kept in a noninoculated medium. Insoluble polysaccharides present in tooth biofilms were quantified, Knoop hardness (KHN) was measured on the enamel adjacent to restorations, and standard 35-mm polarized light photomicrographs were taken as illustrations. Polysaccharide and Knoop hardness results were analyzed with the use of ANOVA, with a split-split-plot statistical design for KHN. Except for Group (1), all groups showed similar caries formation. Biofilm over PB restorations showed the smallest amounts of polysaccharides (14.37 microg/mg), and CSE showed the highest amounts (20.87 microg/mg). All self-etching systems tested were unable to inhibit secondary caries in a bacterial model simulating a high caries challenge, even though there was reduced glucan synthesis provided by the adhesive system containing MDPB and fluoride., ((c) 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005.)

This study evaluates the Knoop microhardness of resin composites cured with different light-emitting diode (LED) based light curing units (LCU) or with a conventional quartz-tungsten-halogen light (QTH). Ten experimental groups with 10 specimens each were used. The specimens were prepared by placing two light-cured resin composites with similar VITA shade A2-microhybrid Filtek Z250/3M ESPE and microfill Durafil VS/Heraeus Kulzer--in a 2.0 mm-thick disc shaped mold. The specimens were polymerized for 40 seconds with the use of one QTH LCU (Optilux 501/Kerr-Demetron) and four LED LCUs: Elipar FreeLight 1 Cordless LED (3M ESPE), Ultrablue II LED with cord (DMC), Ultrablue III LED cordless (DMC) and LEC 470 I (MM Optics). Knoop microhardness was determined at the top and bottom surfaces of the specimens 24 hours following curing. Microhardness values in the microhybrid resin composite group showed no statistically significant differences when cured with LED FreeLight 1 LCU and QTH LCU (p<0.05). The other LED devices evaluated in the study presented lower microhardness values in both surfaces (p<0.05) when compared to QTH. In the microfill resin composite group, no statistically significant differences were observed among all LCUs evaluated on the bottom surfaces (p<0.05). However, on the top surfaces, QTH presented the highest KHN values, and the LED devices presented similar results when compared with KHN values relative to each other (p<0.05).

The existence of unprotected collagen fibrils within the hybrid layer compromises the longevity of restorations. This phenomenon may be avoided if solutions other than strong acids are used for dentin demineralization. The hypothesis to be tested is that bond durability may be improved by EDTA demineralization. Dentin surfaces (human and bovine) were bonded: (1) after phosphoric-acid-etching, and after EDTA demineralization with (2) a total-etch adhesive and (3) a self-etching adhesive. After the teeth were sectioned into beams, half of the specimens were immersed in NaOCl, while the other half was immersed in water. Beams were tested to failure in tension. ANOVA and multiple-comparisons tests were used (P < 0.05). No differences in bond strength were found among the 3 bonding procedures, although bonds made to human molars were 43-61% higher than those to bovine incisors. After NaOCl immersion, only specimens subjected to EDTA demineralization maintained the initial bond strength. We conclude that the collagen network is better-preserved after EDTA demineralization.

This study evaluated artificial secondary caries around restorative materials, induced by means of chemical or microbiological models. The following materials were used randomly to restore 130 dental blocks: (1) zinc-oxide eugenol-free temporary filling: Coltosol (Coltène/Whaledent Inc.; n = 30), (2) silver amalgam: Permite C (SDI Limited, n = 20), (3) composite resin: Filtek Z250 (3M ESPE; n = 20), (4) glass-ionomer cement: Fuji II (GC America Inc.; n = 20), (5) resin-modified glass ionomer: Vitremer (3M ESPE; n = 20), and (6) polyacid modified resin: Dyract AP (Dentsply; n = 20). Ten specimens of Group 1 were kept in humidity, and had no carious formation (NC). Ten specimens of each group were submitted to pH cycling (CG, n = 60), and the others were immersed in a medium containing Streptococcus mutans and sucrose (BG, n = 60). Mineral content was determined by microhardness assessment, and lesion depth was measured in polarized light photomicrographs. In the chemical model (CG), mineral content values in the vicinities of restoration were high for Groups 5 (75.7 +/- 11.9), 4 (70.8 +/- 14.2), and NC (95.4 +/- 3.8); intermediate for Groups 1 (55.8 +/- 18.5), 6 (45.6 +/- 11.0), and 2 (44.3 +/- 11.2); and reduced for Group 3 (34.7 +/- 9.7). In the microbiological model (BG), results were similar to CG, although there was less demineralization. The highest lesion depths were found for Groups 3 (182.3 +/- 33.2) in CG and 6 (126.5 +/- 42.8) in BG, when compared to Group 5 (114.6 +/- 26.0 and 56.2 +/- 33.2, respectively). In both models of caries induction, ionomeric materials showed a superior cariostatic effect when compared to the other restorative materials., (Copyright 2005 Wiley Periodicals, Inc.)

The aim of this study was to determine the effect of 10% NaOCl gel and 10% NaOCl solution on dentin bond strengths of four adhesive systems. One hundred eighty bovine incisors were ground to achieve a flat polished surface, then divided into 12 groups: Gluma One Bond [G1-control; G2-NaOCl solution; G3-NaOCl gel]; Prime & Bond 2.1 [G4-control; G5-NaOCl solution; G6-NaOCl gel]; Single Bond [G7-control; G8-NaOCl solution; G9-NaOCl gel]; Prime & Bond NT [G10-control; G11-NaOCl solution; G12-NaOCl gel]. Dentin was etched, rinsed, and blot dried. For the experimental groups, after acid etching, 10% NaOCl solution or 10% NaOCl gel was applied for 60 s, rinsed, and blot dried. Composite resin was inserted and light cured. Shear bond strengths were tested with a crosshead speed of 0.5 mm/min. The mean values MPa (SD) were analyzed with two-way ANOVA and Tukey's tests (alpha < 0.01). Ten percent NaOCl solution significantly increased Gluma One Bond strength. No effect was observed for the other adhesives. The 10% NaOCl gel did not affect bond strengths. Ten percent NaOCl gel was less effective on collagen removal as compared to 10% NaOCl solution. The influence of collagen removal on bond strength is dependent on adhesive system, where both the solvent and the monomer can influence the results.

Background: Studies have shown that bleaching agents interfere with the adhesion of composite resin placed immediately after bleaching., Purpose: The aim of this study was to evaluate the shear bond strengths of composite resin after four different durations since the time of nonvital bleaching (1 d and 1, 2, and 3 wk)., Materials and Methods: Two hundred seventy bovine teeth were assigned to nine groups (n = 30) according to the bleach used and the time between bleaching and restoration: group 1--sodium perborate (SP), 1 day after bleaching (AB); group 2--SP, 1 week AB; group 3--SP, 2 weeks AB; group 4--SP, 3 weeks AB; group 5--37% carbamide peroxide (CP), 1 day AB; group 6--CP, 1 week AB; group 7--CP, 2 weeks AB; group 8--CP, 3 weeks AB; group 9--control group (no treatment). After the bleaching treatment, the teeth in each group were sectioned and the enamel and dentin were separated. The teeth were cut, embedded in polyester resin, and polished to obtain flat enamel and dentin surfaces. The adhesive system was applied and a cylinder of composite resin was bonded on each flat surface. The specimens were stored in distilled water for 7 days at 37 degrees C. The shear bond strength test was performed in a universal test machine (Emic DL-500, São José dos Pinhais, São Paulo, Brazil) at a crosshead speed of 0.5 mm/min., Results: The data were subjected to analysis of variance, Dunnett's t-test, and Tukey's least significant difference at p < or = .05 and showed a statistically significant decrease in bond strengths of composite resin for enamel and dentin 1 day after the nonvital bleaching., Clinical Significance: The decrease in shear bond strength values is time dependent. A delay in bonding procedures for composite resin restoration is recommended. According to the results, a satisfactory time to perform the restoration of composite resin for both enamel and dentin is 2 weeks after bleaching.