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1.
J Esthet Restor Dent ; 36(8): 1093-1099, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38291733

ABSTRACT

OBJECTIVE: Agenesis of the maxillary permanent lateral incisors is a condition that requires treatment aimed at improving the esthetics, even at an early age. However, traditional therapeutic protocols are long, invasive and have limitations and contraindications imposed by the age of the patient. CLINICAL CONSIDERATIONS: Recent developments in restorative dentistry have provided a new approach to this clinical situation, in particular when the deciduous laterals are retained. We report two cases regarding the management of missing lateral incisors using Biologically Active Intrasulcular Restoration (BAIR) technique. The BAIR technique allows us to transform the shape of the deciduous lateral incisor into the permanent, acting both on the dental morphology and proportions, and on the appearance of the soft tissues and the gingival parables. CONCLUSIONS: The BAIR technique is a valid approach to cases of agenesis of the maxillary permanent lateral incisors, when the deciduous are retained. It does not require any preparation of the dental tissues, is reversible and minimally invasive. It is applicable to patients of all ages, and results are obtained in a single appointment. CLINICAL SIGNIFICANCE: The BAIR technique allows a biomimetic conservative approach for the rehabilitation of congenitally missing permanent lateral incisors, when the deciduous are retained. It is a non-invasive protocol and effective in successfully restoring esthetics.


Subject(s)
Incisor , Maxilla , Female , Humans , Male , Anodontia/therapy , Biomimetics , Dental Restoration, Permanent/methods , Esthetics, Dental , Incisor/abnormalities , Maxilla/abnormalities , Tooth, Deciduous/abnormalities , Adolescent
2.
Pediatr Pulmonol ; 59(2): 472-481, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38088231

ABSTRACT

INTRODUCTION: A significant percentage of patients who survived the Coronavirus Infection Disease 2019 (COVID-19) showed persistent general and respiratory symptoms even months after recovery. This condition, called Post-Acute Sequelae of COVID-19 or Long-Covid syndrome (LCS), has been described also in children with positive history for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Little is known about the pathophysiologic mechanisms underlying this syndrome. The aim of this study was to investigate any difference between children with LCS and asymptomatic peers with previous COVID-19 in terms of lung function and lung ultrasound (LUS) patterns. Secondly, we tested associations between lung function abnormalities and LUS findings with Long-Covid. METHODS: We carried out a prospective, descriptive, observational study including 58 children aged 5-17 years: 28 with LCS compared to 30 asymptomatic children with previous COVID-19. We collected demographic data, history of asthma, allergy or smoke exposure, and acute COVID-19 symptoms. After a median period of 4.5 months (1%-95% range 2-21) since the infection, lung function was assessed by spirometry, body plethysmography, diffusion lung capacity for carbon monoxide (DLCO). Airways inflammation was investigated by fractional exhaled nitric oxide (FeNO). LUS was performed independently by two experienced clinicians. RESULTS: We found that children with LCS were older than controls (mean (SD) 12 (4.1) vs. 9.7 (2.6); p = .04). Children with LCS complained more frequently fatigue (46.4%), cough (17.9%), exercise intolerance (14.3%) and dyspnea (14.3%). Lung function was normal and similar between the two groups. The frequency of LUS abnormalities was similar between the two groups (43.3% children with LCS vs. 56.7% controls; p = .436). Children with LCS showed lower FeNO values (log difference -0.30 (CI 95% -0.50, -0.10)), but no association of LCS with a lower lung function and abnormal LUS findings was found. CONCLUSIONS: LCS seems to be more frequent in older age children. Lung functional and structural abnormalities were not different between children with LCS and asymptomatic subjects with previous COVID-19. In addition, children with LCS showed lower FeNO values than controls, suggesting its potential role as a marker in LCS. However, further and larger studies are needed to confirm our findings.


Subject(s)
COVID-19 , Child , Humans , COVID-19/complications , SARS-CoV-2 , Post-Acute COVID-19 Syndrome , Prospective Studies , Lung/diagnostic imaging
3.
J Dermatolog Treat ; 34(1): 2246602, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37580895

ABSTRACT

Background: Dupilumab has been shown to be a safe and effective drug for the treatment of atopic dermatitis (AD) in children from 6 months to 11 years in randomized clinical trials. Aim: The aim of this real-life study was to determine the effectiveness in disease control and safety of dupilumab at W52 in moderate-to-severe AD children aged 6-11 years.Methods: All data were collected from 36 Italian dermatological or paediatric referral centres. Dupilumab was administered at label dosage with an induction dose of 300 mg on day 1 (D1), followed by 300 mg on D15 and 300 mg every 4 weeks (Q4W). Treatment effect was determined as overall disease severity, using EASI, P-NRS, S-NRS and c-DLQI at baseline, W16, W24, and W52. Ninety-six AD children diagnosed with moderate-to-severe AD and treated with dupilumab were enrolled.Results: Ninety-one (94.8%) patients completed the 52-week treatment period and were included in the study. A significant improvement in EASI score, P-NRS, S-NRS and c-DLQI was observed from baseline to weeks 16, 24 and 52.Conclusions: Our real-life data seem to confirm dupilumab effectiveness and safety in paediatric patients. Moreover, our experience highlighted that patients achieving clinical improvement at W16 preserved this condition over time.


Subject(s)
Dermatitis, Atopic , Humans , Child , Dermatitis, Atopic/drug therapy , Dermatitis, Atopic/diagnosis , Retrospective Studies , Double-Blind Method , Treatment Outcome , Severity of Illness Index
4.
Biomedicines ; 11(2)2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36830772

ABSTRACT

Asthma, chronic urticaria, and atopic dermatitis are some of the most numerous allergic diseases affecting children. Recent advances in the understanding of their specific intracellular molecular pathways have led to the approval of monoclonal antibodies targeting definite inflammatory molecules in order to control symptoms and improve quality of life. Less is known about other allergic and immunologic disorders such as rhinosinusitis with nasal polyps, eosinophilic esophagitis, anaphylaxis, and food allergy undergoing allergen immunotherapy. The increasing evidence of the molecular mechanisms underlying their pathogeneses made it possible to find in children new indications for known biological drugs, such as omalizumab and dupilumab, and to develop other ones even more specific. Promising results were recently obtained, although few are currently approved in the pediatric population. In this review, we aim to provide the latest evidence about the role, safety, and efficacy of biologic agents to treat allergic and immunologic diseases in children.

5.
Dent J (Basel) ; 12(1)2023 Dec 25.
Article in English | MEDLINE | ID: mdl-38248211

ABSTRACT

Predictable results in the aesthetic treatment of anterior teeth can be obtained by resorting to the concept of dental aesthetics and, in particular, defining the ideal tooth dimensions and proportions to obtain a harmonious smile. Considering the great variety of articles dealing with the topic, and the lack of updated reviews, this narrative literature review aims to evaluate current knowledge on anterior teeth dimensions and to verify the existence and the potential applications of the anterior teeth proportioning theories (Golden Proportion, Golden Percentage, RED Proportion, and Golden Rectangle). PubMed, Embase, Cochrane Library, and Google Scholar databases were comprehensively searched using different keywords and term combinations. The research includes articles published up to June 2023, no time limits were set, and only articles in English were included. Inclusion criteria comprehended reviews, clinical studies, and in-vitro studies. A total of 66 articles were selected. Two main topics were identified: "Anterior teeth dimensions", "Golden Proportions, Golden Percentage, RED Proportions, and Golden Rectangle". As far as tooth dimensions are concerned, different width ranges are recognized for men and women and for different ethnic groups. Perfectly symmetric contralateral elements are found in low percentages of subjects. The correlation between dental dimensions and facial parameters is not always present, and it strongly depends on the sample's ethnicity and gender. Ideal tooth proportions were only partially identified.

6.
Materials (Basel) ; 15(14)2022 Jul 13.
Article in English | MEDLINE | ID: mdl-35888342

ABSTRACT

Composite resins are considered the material of choice for esthetic direct restorations, considering both their satisfying esthetic and mechanical properties. The success of composite resin restorations depends highly on their color stability. Discoloration causes color mismatch, consequent patient dissatisfaction, and eventually additional costs for correction/replacement of the restoration. The purpose of this study was to evaluate the degree of pigment penetration within the composite resins, in order to understand how discoloration can be treated properly. Two different commercially available composite resins were compared in the study: a nano-filled composite resin and a non-homogeneous micro-hybrid composite resin. A coffee solution was used to induce staining of the materials. Subsequently, the penetration of the pigments was measured by analyzing the color from the outside to the inside of the specimen. 14 levels were analyzed starting from 0.1 mm to 3.0 mm in depth. The ANOVA test demonstrated a statistically significant difference (p < 0.0001) between test and control groups up to a depth of 1.0 mm for the nano-filled composite and up to a depth of 2.0 mm for the non-homogeneous micro-hybrid composite. The two composite resin materials, subjected to pigmenting treatment, underwent a color variation with different patterns.

7.
Biomedicines ; 10(4)2022 Mar 24.
Article in English | MEDLINE | ID: mdl-35453508

ABSTRACT

Susceptibility to asthma is complex and heterogeneous, as it involves both genetic and environmental insults (pre- and post-birth) acting in a critical window of development in early life. According to the Developmental Origins of Health and Disease, several factors, both harmful and protective, such as nutrition, diseases, drugs, microbiome, and stressors, interact with genotypic variation to change the capacity of the organism to successfully adapt and grow in later life. In this review, we aim to provide the latest evidence about predictive risk and protective factors for developing asthma in different stages of life, from the fetal period to adolescence, in order to develop strategic preventive and therapeutic interventions to predict and improve health later in life. Our study shows that for some risk factors, such as exposure to cigarette smoke, environmental pollutants, and family history of asthma, the evidence in favor of a strong association of those factors with the development of asthma is solid and widely shared. Similarly, the clear benefits of some protective factors were shown, providing new insights into primary prevention. On the contrary, further longitudinal studies are required, as some points in the literature remain controversial and a source of debate.

8.
Biomedicines ; 9(11)2021 Nov 04.
Article in English | MEDLINE | ID: mdl-34829844

ABSTRACT

Atopic dermatitis and urticaria are two invalidating skin disorders that are very common in children. Recent advances in the understanding of their specific intracellular molecular pathways have permitted the development of precise biological molecules, targeting inflammatory mediators and arresting the pathogenetic pathways of skin diseases. Many biologics with promising results have been studied, although few are currently approved in children. In this review, we aim to provide the latest evidence about the use, indications, efficacy and safety of biologic therapies to treat atopic dermatitis and chronic urticaria in children and adolescents.

9.
Biomedicines ; 9(7)2021 Jun 30.
Article in English | MEDLINE | ID: mdl-34209312

ABSTRACT

Severe asthma is a heterogeneous, complex and chronic disease widespread in the pediatric population. According to the recent findings about the different endotypes of asthma in children, each one characterized by specific intracellular molecular pathways, several innovative biologic therapies have been developed. Due to their precise ability to target specific inflammatory type 2 mediators, biologics have revolutionized the care of chronic allergic diseases in the pediatric and adult population. In this review, we aim to provide the latest evidence about the use, indications, efficacy and safety of biologic therapies to treat severe asthma in children and adolescents.

10.
J Clin Med ; 9(9)2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32825796

ABSTRACT

Retinopathy of prematurity (ROP) is a leading cause of potentially preventable blindness in low birth weight preterm infants. Several perinatal and postnatal factors contribute to the incomplete maturation of retinal vascularization, leading to oxidative stress damage. Literature data suggest that the lack of equilibrium between pro-oxidants and anti-oxidants plays a key role. In the last decade, there has been an increasing interest in identifying the antecedents of ROP and the relevant pathogenic mechanisms involved. In this context, a panel of biomarkers was investigated in order to achieve early detection of oxidative stress occurrence and to prevent retinal damage. Several nutritional elements have been found to play a relevant role in ROP prevention. At this stage, no conclusive data have been shown to support the usefulness of one biomarker over another. Recently, the Food and Drugs Administration, the European Medicine Agency, and the National Institute of Health proposed a series of criteria in order to promote the inclusion of new biomarkers in perinatal clinical guidelines and daily practice. The aim of the present review is to offer an update on a panel of biomarkers, currently investigated as potential predictors of ROP, highlighting their strengths and weaknesses.

11.
Int J Prosthodont ; 33(2): 192-201, 2020.
Article in English | MEDLINE | ID: mdl-32069344

ABSTRACT

PURPOSE: To determine the accuracy of direct digital impressions in vivo and compare it to that of conventional impressions in order to assess whether intraoral scanners could be a legitimate alternative for the manufacturing of fixed prosthodontics. MATERIALS AND METHODS: An electronic systematic search was conducted in the PubMed, Web of Science, Embase, and Cochrane Library databases using query terms such as digital impression; intraoral digital impression; intraoral scanner; intraoral digital scanner; conventional impression; analogue impression; and accuracy. The outcomes were the trueness and precision of digital impressions in comparison to those of high-precision conventional impressions in vivo. RESULTS: Six studies matched the inclusion criteria. Four studies investigated the precision of digital impressions, while two studies focused on their trueness. Even if all the authors agreed that conventional impressions were more accurate than digital impressions in vivo, they gave different opinions on using intraoral scanners in a clinical context without causing misfit of the final restoration. CONCLUSION: According to the results of the present review, conventional impressions performed using high-precision impression materials showed greater accuracy than digital impressions. However, additional studies assessing the accuracy of digital impressions in a wider variety of clinical situations are highly recommended.


Subject(s)
Dental Impression Technique , Models, Dental , Computer-Aided Design , Dental Impression Materials , Humans , Imaging, Three-Dimensional , Prosthodontics
12.
Dent J (Basel) ; 7(3)2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31374820

ABSTRACT

Background. Reliable bonding between resin composite cements and high strength ceramics is difficult to achieve because of their chemical inertness and lack of silica content that makes etching impossible. The purpose of this review is to classify and analyze the existing methods and materials suggested to improve the adhesion of zirconia to dental substrate by using composite resins, in order to explore current trends in surface conditioning methods with predictable results. Methods. The current literature, examining the bond strength of zirconia ceramics, and including in vitro studies, clinical studies, and a systematic review, was analyzed. The research in the literature was carried out using PubMed and Cochrane Library databases, only papers in English, published online from 2013 to 2018. The following keywords and their combinations were used: Zirconia, 3Y-TZP, Adhesion, Adhesive cementation, Bonding, Resin, Composite resin, Composite material, Dentin, Enamel. Results. Research, in PubMed and Cochrane Library databases, provided 390 titles with abstracts. From these, a total of 93 publications were chosen for analysis. After a full text evaluation, seven articles were discarded. Therefore, the final sample was 86, including in vitro, clinical studies, and one systematic review. Various adhesive techniques with different testing methods were examined. Conclusions. Airborne-particle abrasion and tribo-chemical silica coating are the pre-treatment methods with more evidence in the literature. Increased adhesion could be expected after physico-chemical conditioning of zirconia. Surface contamination has a negative effect on adhesion. There is no evidence to support a universal adhesion protocol.

13.
Am J Dent ; 27(6): 323-9, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25707087

ABSTRACT

ABSTRACT: Purpose: To compare the bond strength to human dentin for a variety of adhesive materials, including self-adhesive resin composites, self-etch and etch-and-rinse adhesive systems and glass-ionomer cement by means of micro shear bond strength (µSBS) test and SEM observations. METHODS: Seventy-two human molars were sectioned to obtain a 2 mm-thick slab of mid-coronal dentin and were subsequently randomly divided into nine groups (n = 8). Nine conical frustum-shaped build-ups were constructed on the occlusal surface of each dentin slab using bonding agents (Group 1: OptiBond FL; Group 2: OptiBond XTR) combined with a resin composite (Premise Flow), self-adhesive resin composites (Group 3: RelyX Unicem; Group 4: RelyX Unicem 2; Group 5: SmartCem2; Group 6: SpeedCEM; Group 7: Maxcem Elite; Group 8: Vertise Flow) and a glass-ionomer cement (Group 9: Ketac-Fil). Specimens were subjected to µSBS test and observed with SEM. Data were analyzed by a mixed model and chi-square test. RESULTS: The bond strengths measured in Groups 3-9 were significantly lower than those recorded in Groups 1 and 2. There were no significant differences in bond strengths between Groups 1 and 2 or between Groups 4 through 8. The bond strength measured in Group 9 was significantly lower than those recorded in Groups 4, 5, and 6 but was not significantly different than those recorded in Groups 3, 7, and 8. Failures were mainly adhesive in all groups.


Subject(s)
Dental Bonding , Dental Cements , Humans , In Vitro Techniques , Microscopy, Electron, Scanning
14.
Am J Dent ; 26(6): 341-6, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24640439

ABSTRACT

PURPOSE: To compare the bond strength to human primary dentin of a self-adhesive light-curing resin composite, a self-etch adhesive and a glass-ionomer cement by means of microshear bond strength (pSBS) test and scanning electron microscopic (SEM) observations. METHODS: 75 human primary molars were sectioned to obtain a 2 mm-thick slab of mid-coronal dentin, randomly divided into three groups (n=25). Nine conical frustum-shaped buildups were constructed on the occlusal surface of each dentin slab using a self-adhesive light-curing resin composite (Vertise Flow; Group 1), bonding agent (Optibond All-in-One; Group 2) combined with resin composite (Premise Flow) and a glass-ionomer cement (Ketac-Fil; Group 3). After thermocycling, specimens were subjected to microSBS test. All debonded specimens were observed at SEM. Data were analyzed by a mixed model and chi-square test. RESULTS: The bond strength measured in Group 1 (9.0 +/- 4.5 MPa) was significantly lower than that one recorded in Group 2 (20.2 +/-12.5 MPa) although it was significantly higher than the one recorded in Group 3 (4.8 +/- 2.3 MPa). Failures were mainly adhesive in all groups.


Subject(s)
Dental Bonding , Dental Materials/chemistry , Dentin/ultrastructure , Tooth, Deciduous/ultrastructure , Adhesiveness , Composite Resins/chemistry , Dental Stress Analysis/instrumentation , Dentin-Bonding Agents/chemistry , Glass Ionomer Cements/chemistry , Humans , Light-Curing of Dental Adhesives , Maleates/chemistry , Materials Testing , Microscopy, Electron, Scanning , Resin Cements/chemistry , Shear Strength , Stress, Mechanical , Surface Properties , Temperature , Time Factors
15.
Am J Dent ; 24(5): 271-6, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22165453

ABSTRACT

PURPOSE: To compare a two-step etch-and-rinse adhesive system and a one-step self-etch adhesive system in order to evaluate the influence of clinical experience on dentin bond strength. METHODS: 24 human molars were sectioned to obtain two 1 mm-thick slabs of mid-coronal dentin. Both surfaces of one of the two slabs that were obtained from each tooth were treated with a two-step etch-and-rinse adhesive (OptiBond Solo Plus), while both surfaces of the other slab were treated with a one-step self-etch adhesive (OptiBond All-In-One). 24 undergraduate, second-year students applied the adhesive on one of the two surfaces of each slab (Student group), while 12 dentists with experience in adhesive restorative dentistry (Expert group) applied the same adhesive on the other surface of the slab. Nine conical frustum-shaped resin composite (Premise Flowable) build-ups, whose smaller base was bonded to the dentin surface, were constructed on both surfaces of each dentin slab using a custom-made device. After thermocycling, specimens were subjected to microshear bond strength test. Data were analyzed by a multilevel statistical model. RESULTS: The interaction term Experience x Adhesive resulted statistically significant (P < 0.0001). The bond strength (MPa) resulting from the self-etch adhesive was similar in the Student (27.8 +/- 9.0) and in the Expert group (26.5 +/- 7.0). The etch-and-rinse adhesive bond strength within the Student group (23.6 +/- 10.4) was lower than that within the Expert group (28.1 +/- 8.9).


Subject(s)
Acid Etching, Dental/methods , Clinical Competence , Dental Bonding , Dentin-Bonding Agents , Composite Resins , Dentin , Dentists , Humans , Methacrylates , Molar , Resin Cements , Students, Dental
16.
Riv Psichiatr ; 46(4): 250-64, 2011.
Article in Italian | MEDLINE | ID: mdl-21938079

ABSTRACT

AIMS: A robust psychopathological and psychotherapeutic tradition underscores the importance of the clinician's feelings in the assessment and therapeutic process. Our aim is to develop an instrument to evaluate psychiatrist' experience induced by each patient. This paper describes the development and preliminary validation of this instrument. METHODS: Based on the relevant literature and our clinical experience, we developed a self-completed questionnaire consisting of 65 items covering various aspects of the clinician' emotional resonance. Ten psychiatrists completed our questionnaire immediately after first clinical interviews involving a total of 125 patients with various psychiatric diagnoses. Also, they completed the Profile of Mood State (POMS) immediately before and after these interviews. The factor structure and convergent validity of the questionnaire was examined. RESULTS: We identified a six-factor structure. The factors showed acceptable internal consistency and were interpretable as different aspects of the clinician-patient interaction as experienced by the clinician. There was a consistent pattern of correlations between factor scores and changes in POMS scale scores during the clinical interviews. DISCUSSION: The study results, though preliminary, suggest that clinicians' subjective reactions during their interactions with patients can be validly and reliably measured. Quantitative measurement of clinician's subjectivity is potentially useful in both clinical and research settings.


Subject(s)
Emotions , Mental Disorders/diagnosis , Psychiatry , Surveys and Questionnaires , Adult , Evidence-Based Medicine , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Psychometrics , Reproducibility of Results
17.
J Am Dent Assoc ; 141(11): 1357-64, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21037194

ABSTRACT

BACKGROUND: The aim of this split-mouth, randomized controlled trial was to compare the whitening results of at-home and in-office tooth bleaching techniques and the longevity of their effects at nine months after teeth had been bleached. METHODS: The authors conducted a study involving a 14-day bleaching period, during which the first maxillary premolars of 17 participants, who were 20 to 25 years of age, were bleached by means of either an at-home technique involving 10 percent carbamide peroxide or an in-office technique involving 38 percent hydrogen peroxide. The authors recorded color variables as proposed by the Commission Internationale de l'Eclairage-lightness (L*), redness (a*) and yellowness (b*)-by using a spectrophotometer at baseline and at one week, one month and nine months after bleaching. They also calculated a whiteness (W) index that was based on the distance of the color value in the color space from a nominal white point. RESULTS: At the nine-month recall visit, comparison between the at-home and the in-office techniques did not show significantly different values for L* (P = .448), a* (P = .350), b* (P = .144) and W (P = .151) color variables. None of the participants experienced any adverse events related to the bleaching during the treatment period. CONCLUSIONS: The study results showed no clinically significant difference in bleaching efficacy. Both techniques produced satisfactory and long-lasting bleaching results. CLINICAL IMPLICATIONS: In young adults, either the at-home or the in-office technique can be used effectively.


Subject(s)
Tooth Bleaching Agents/therapeutic use , Tooth Bleaching/methods , Adult , Bicuspid/drug effects , Bicuspid/pathology , Carbamide Peroxide , Color , Dental Offices , Dental Prophylaxis , Equipment Design , Female , Follow-Up Studies , Humans , Hydrogen Peroxide/administration & dosage , Hydrogen Peroxide/therapeutic use , Male , Maxilla , Oxidants/administration & dosage , Oxidants/therapeutic use , Peroxides/administration & dosage , Peroxides/therapeutic use , Self Care , Single-Blind Method , Spectrophotometry , Time Factors , Tooth Bleaching/instrumentation , Tooth Bleaching Agents/administration & dosage , Treatment Outcome , Urea/administration & dosage , Urea/analogs & derivatives , Urea/therapeutic use , Young Adult
18.
Eur J Esthet Dent ; 5(3): 300-10, 2010.
Article in English | MEDLINE | ID: mdl-20820459

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate the in vitro color stability of bleached teeth by means of a 6-day staining procedure. MATERIAL AND METHODS: 20 caries-free randomly divided into two groups. Test group: a bleaching agent (Zoom 2, Discus Dental) was applied to the labial surfaces following the manufacturer's instructions. CONTROL GROUP: no bleaching treatment. using a thermo-cycling device, all teeth were alternately immersed in a 0.9% saline solution at 37 °C for 1 hour, and in a coffee solution at 55 °C for another hour, in order to simulate the natural tooth-staining process. This procedure was repeated 12 times a day for 6 days. Teeth were polished once a day with a rubber cup and polishing paste. CIELAB color variables (L, a, b) were assessed by means of a spectrophotometer (VITA Easyshade®) and a custom alignment device at baseline, after bleaching, and once a day throughout the 6-day staining treatment. The bleaching result and the color stability of bleached and control group teeth were assessed by matched pair t test and MANOVA. RESULTS: The bleaching agent had a significant whitening effect. The staining treatment did not produce any significant color change on bleached teeth, which maintained the same whiteness achieved after the bleaching treatment. The staining treatment did not produce any significant color change on control teeth. The two groups showed significant differences in both whiteness and lightness changes as a result of the polishing treatment. CONCLUSIONS: The Zoom 2 whitening agent produced immediate and long-lasting bleaching results, even if the reduction of b value mainly occurred 24 and 48 hours after the bleaching treatment.


Subject(s)
Hydrogen Peroxide/therapeutic use , Oxidants/therapeutic use , Tooth Bleaching/methods , Tooth Discoloration/drug therapy , Tooth/pathology , Coffee , Color , Dental Prophylaxis , Humans , Materials Testing , Phototherapy , Sodium Chloride , Spectrophotometry , Temperature , Time Factors , Tooth/drug effects , Tooth Discoloration/pathology
19.
J Dent ; 37(8): 638-42, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19477571

ABSTRACT

OBJECTIVES: To compare, by means of the push-out test, the interfacial strength of two dual resin cements and one light-curing cement when used in translucent fiber post cementation. METHODS: Thirty-nine, endodontically treated, single canal, extracted human bicuspids were selected. Translucent fiber posts (RelyX Fiber Post) were luted into the root canal using three resinous luting systems (n=13). Dual-curing technique (DC): the specimens were treated with Excite DSC and RelyX ARC, which were light-cured simultaneously through the post for 60s. Self-adhesive dual-curing technique (SADC): the specimens were treated with RelyX Unicem, which was light-cured through the post for 60s. Light-curing technique (LC): the specimens were treated with Excite DSC and Tetric Flow, which were simultaneously light-cured through the post for 60s. The specimens were transversally sectioned into six slices in order to perform the push-out test. Data were analyzed by two-way ANOVA followed by the Tukey-Kramer test for post-hoc comparisons at alpha=0.05. RESULTS: At every region, results did not show any statistical difference between the DC and LC techniques. With the LC technique bond strength values were lower at the apical region than those recorded at the coronal and middle regions. At the coronal and middle regions, bond strength values for the SADC technique were lower than those resulting when using the other two techniques. At the apical region, there was not significant difference in bond strength between the luting techniques tested. CONCLUSIONS: The interfacial strength between light-curing cement and root canal is equivalent to the interfacial strength between dual-curing cement and root canal.


Subject(s)
Dental Bonding/methods , Dental Materials/chemistry , Dental Pulp Cavity/drug effects , Post and Core Technique/instrumentation , Resin Cements/chemistry , Analysis of Variance , Curing Lights, Dental , Dental Stress Analysis , Humans , Materials Testing , Resin Cements/radiation effects , Statistics, Nonparametric
20.
Eur J Oral Sci ; 117(2): 204-7, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19320732

ABSTRACT

The aim of the present study was to compare the technique currently used for carrying out the microtensile bond strength (muTBS) test with an alternative method. Six human molars were sectioned transversally to obtain two specimens from each tooth: a 0.75-mm-thick slab of mid-coronal dentin, which presented an occlusal and a cervical surface (DS specimen); and the remaining section of the tooth with an exposed dentin surface (SS specimen). A self-etch adhesive system and four layers (2 mm each) of resin composite were applied to the sectioned surfaces by means of a custom-made special device, in order to obtain a cylindrical build-up. Each specimen was sectioned lengthwise to obtain multiple sticks. The end sections of sticks obtained from DS specimens were resin composite, whereas the middle section was dentin. The sticks obtained from SS specimens were half resin composite and half dentin. The specimens were fractured under tension. Data were subjected to a multilevel statistical model. The maximum load at break of SS specimens was higher than that of DS specimens. This modified methodology offers two main advantages over the traditional procedure: easier manipulation of the sticks; and the possibility of testing deep dentin.


Subject(s)
Composite Resins/chemistry , Dental Bonding/methods , Dental Stress Analysis/methods , Dentin-Bonding Agents/chemistry , Dentin/chemistry , Tensile Strength , Humans
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