Does MIH Affects Preoperative and Intraoperative Hypersensitivity?

OBJECTIVE: Hypersensitivity is an important problem that is encountered during the treatment of hypomineralized teeth. The aim of this prospective study was to compare responses to electrical pulp tests (EPTs) and cold tests among carious teeth with and without molar incisor hypomineralization (MIH) before and after the administration of local anesthesia for caries removal Results: The EPT results of anesthetized carious teeth without MIH were significantly higher than those of carious teeth with MIH (p = 0.011). The cold test results were significantly higher for anesthetized carious teeth with MIH than for those without MIH (p = 0.0001). Intraoperative pain was significantly higher for carious teeth with MIH (p = 0.003). CONCLUSIONS: The results of this study suggest that even after achieving sufficient anesthesia, hypersensitivity remains a clinical problem in MIH-affected carious molars. The results presented in this study indicate that this phenomenon is not related to achieving effective local anesthesia; therefore, behavior management in such cases is of the utmost importance compared to relying on adjacent anesthetic methods.

Age estimation in Turkish children and young adolescents using fourth cervical vertebra.

This study aimed to test radiographic projections of the posterior and anterior sides of the C4 vertebral body for age estimation in a cross-sectional sample of Turkish children and adolescents from the Baskent University Faculty of Dentistry. A sample of 232 x-rays from individuals aged between 5 and 15 years (101 boys and 131 girls) was analysed to investigate the correlation of age and changes in the projection ratio of the anterior and posterior sides of the body of the fourth cervical vertebra (Vba) in lateral cephalograms. The Normal Bayesian Calibration (NBC) model for age estimation was used to assess the relationship between Vba and age. The intra-observer repeatability and inter-observer agreement were 0.95 and 0.94, respectively. Age distribution gradually increased as Vba increased up to 14 years in both sexes. The difference between chronological and estimated ages did not increase with the increase in age. Calibration distributions of the dataset by the evaluation of Vba suggested mean absolute errors (MAEs) of 0.879 years and 0.906 years (mean interquartile ranges (MIQRs) 1.290 and 1.435 years)) in boys and girls, respectively. The biases of the estimates (ßERR) were 0.013 and 0.027 for boys and girls, respectively. In conclusion, the NBC method on Vba variable appears to be suitable for age estimation in Turkish children and adolescents.

Evaluation of Possible Associated Factors for Early Childhood Caries and Severe Early Childhood Caries: A Multicenter Cross-Sectional Survey.

OBJECTIVES: The present study evaluated associated factors for developing early childhood caries (ECC) and Severe-ECC (S-ECC) in a group of children aged 24-71 months. Potential positive effects of early dental visit on formation of ECC is investigated as well. STUDY DESIGN: This was a multicenter, cross-sectional study conducted at three governmental and university pediatric dentistry clinics in 408 preschool children who were randomly selected from a total of 4116 children. The questionnaires administered to the mothers by interview and intraoral examination performed by calibrated pediatric dentists. The children were evaluated in three groups according to their caries experience as who had caries free, ECC and S-ECC. RESULTS: The following factors were significantly associated with caries formation: 1. Prolonged (i.e., >18 months) breastfeeding in preterm babies (OR=2.4) 2. Prolonged breastfeeding in children who started tooth brushing after 1.5 years of age (OR=3.7), 3. Sugar (p<0.001) and fruit-juice consumption (p<0.0001), and 4. Lack of periodic dental examination (p<0.05). Parental smoking habit does not significantly affect ECC development. Nocturnal bottle feeding and nocturnal feeding also affected S-ECC formation significantly (p=0.043 and p=0.005, respectively). CONCLUSIONS: There is a significant difference between the children with caries and caries-free associated with the brushing initiation age started before or after 18 months. If a child is under the risk of multiple caries factors, it is very difficult to evaluate which habits affect the caries formation or increase the severity of the caries lesions.

Antimicrobial efficacy of octenidine hydrochloride, MTAD and chlorhexidine gluconate mixed with calcium hydroxide.

OBJECTIVE: The aim of this in vitro study was to investigate whether mixing with calcium hydroxide [Ca(OH)2] affects the antimicrobial action of Octenidine hydrochloride (Octenisept), MTAD and chlorhexidine against Enterococcus faecalis and Candida albicans. MATERIALS AND METHODS: Freshly grown cultures of Enterococcus faecalis, Candida albicans and a mixture of both strains were incubated in agar plates containing brain-heart infusion broth (BHIB). Zones of inhibition were measured at 24 and 48 hours. Statistical analysis was performed using Mann-Whitney U test and Kruskal-Wallis one-way analysis of variance (ANOVA, both p=0.05). RESULTS: Mixing with Ca(OH)2 significantly increased the antibacterial effect of Octenisept (p<0.05), but did not alter its antifungal activity. Only chlorhexidine showed more antibacterial and antifungal efficiency compared to its Ca(OH)2-mixed version (both p<0.05). Mixing with Ca(OH)2 decreased the antibacterial efficacy of MTAD, but increased its antifungal effect (both p<0.05). CONCLUSION: These results demonstrate the differential effects of Ca(OH)2 addition on the antimicrobial action of the tested endodontic medicaments in vitro. Ca(OH)2 was as effective as its combination with all of the tested medicaments.

Effects of a fluoride-containing casein phosphopeptide-amorphous calcium phosphate complex on the shear bond strength of orthodontic brackets.

The purpose of this study was to investigate the effects of enamel pre-treatment with a new fluoride-containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) complex on the shear bond strength (SBS) of brackets bonded with etch-and-rinse or self-etching adhesive systems. The material comprised 66 extracted human premolars randomly divided into six equal groups with respect to the enamel pre-treatment and adhesive system employed: 1. No pre-treatment and brackets bonded with the etch-and-rinse adhesive system (Transbond XT). 2. Pre-treatment with fluoride-containing CPP-ACP paste (MI Paste Plus) and Transbond XT. 3. Pre-treatment with non-fluoride CPP-ACP paste (MI Paste) and Transbond XT.4. No pre-treatment and brackets bonded with the self-etching adhesive system (Transbond Plus). 5 and 6. Enamel pre-treated as for groups 2 and 3, respectively, and the Transbond Plus. Bonded specimens were subjected to thermal cycling (×1000) before SBS testing. The residual adhesive on the enamel surface was evaluated after debonding with the adhesive remnant index (ARI). Data evaluation was made using one-way analysis of variance and Tukey test for SBS results, and Kruskal-Wallis test for ARI results. The results showed that enamel pre-treatment with either fluoride or non-fluoride CPP-ACP paste had no significant effect on the SBS of the self-etching adhesive system (P > 0.05). Enamel pre-treatment with non-fluoride CPP-ACP in group 3 significantly reduced the SBS of the etch-and-rinse adhesive (P < 0.001), while pre-treatment with fluoride-containing CPP-ACP paste (groups 2 and 5) did not affect debonding values (P > 0.05). The fluoride-containing CPP-ACP did not compromise the SBS of brackets bonded with the tested etch-and-rinse and self-etching systems, but its non-fluoride version significantly decreased the SBS of the etch-and-rinse adhesive system.

Amalgam repair: quantitative evaluation of amalgam-resin and resin-tooth interfaces with different surface treatments.

AIM: The successful addition of new restorative materials to an existing restoration may be the most conservative course of treatment. Repairing amalgam restorations with resin materials remains a viable clinical alternative to amalgam replacement. This in vitro study evaluated the effect of different adhesive systems and surface treatments on the integrity of amalgam-resin and resin-tooth interface after partial removal of pre-existing amalgam. MATERIALS AND METHODS: Fifty defect-free human molars were restored with amalgam occlusally. The teeth were thermocycled (1,000x) between 5 degrees C and 55 degrees C, with a dwell time of 30 seconds. The mesial and distal parts of the amalgam fillings were removed, leaving only the middle part of amalgam. One side of the cavity was finished with a coarse diamond bur, while the other part of the amalgam was finished with a fine diamond bur. The samples were then randomly divided into five groups (n = 10/group) and received the following adhesive systems: Group 1: All Bond 3 (BISCO, Inc); Group 2: Clearfil SE Bond+Alloy Primer (Kuraray); Group 3: Kuraray DC Bond (Kuraray); Group 4: Xeno V (Dentsply); Group 5: XP Bond (Dentsply). All the cavities were restored with resin composite (TPH Spectrum, Dentsply). All the materials were used according to the manufacturer's directions. The specimens were re-thermocycled (1,000x), sealed with nail varnish, stained with 0.5% basic fuchsin for 24 hours, sectioned mesiodistally and photographed digitally. The extent of dye penetration on the tooth-sealant interface was measured by image analysis software (ImageJ, Scion Image, Frederick, Maryland, USA) for both coarse-finished and fine-finished surfaces at the resin-tooth and resin-amalgam interface. The data were analyzed statistically with one-way ANOVA and post hoc Tukey tests (alpha = 0.05). RESULTS: All Bond 3 and XP bond (etch & rinse) produced the best results at each section. All the materials exhibited more microleakage at the amalgam interface than the tooth interface. Surface finishing with different burs did not statistically affect microleakage. CONCLUSION: In terms of microleakage reduction, etch & rinse adhesives may be preferred over self-etch adhesives for amalgam repair.

Effect of acidulated phosphate fluoride and casein phosphopeptide-amorphous calcium phosphate application on shear bond strength of orthodontic brackets.

OBJECTIVE: To evaluate the effect of a recently introduced prophylactic agent, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), on shear bond strength of brackets and compare it with the effect of acidulated phosphate fluoride (APF). MATERIALS AND METHODS: Forty-eight freshly extracted mandibular bovine incisors were used. Teeth were randomly divided into four groups (n = 12) as follows: group 1 served as control, and no pretreatment was performed on the enamel; group 2, enamel was treated with 1.23% APF and CPP-ACP, respectively; group 3, enamel was treated with CPP-ACP; and group 4, enamel was treated with 1.23% APF for 4 minutes. In all groups, brackets were bonded using a conventional acid-etch and bond system (Transbond XT, 3M Unitek, Monrovia, Calif). Bonded specimens were first stored in deionized water at 37 degrees C for 24 hours, subjected to thermal cycling for 1000 cycles, and further stored in distilled water for 6 weeks before debonding procedures. After debonding, teeth and brackets were examined under a stereomicroscope at 10x magnification for any adhesive remaining, in accordance with the modified adhesive remnant index. RESULTS: The shear bond strengths of all experimental groups were significantly higher than that of the control group (P < .01). There was no significant difference between the shear bond strengths of the experimental groups (P > .05). CONCLUSION: The use of CPP-ACP either alone or combined with APF could be considered as an alternative prophylactic application in orthodontic practice since it did not compromise bracket bond strength.

Evaluation of Antibacterial Efficiency of Different Root Canal Disinfection Techniques in Primary Teeth.

BACKGROUND: A successful primary root canal treatment depends on effective shaping and cleaning the root canal system and finally filling it with a hermetic sealer. Clinically, roots of primary teeth are difficult to shape and the irrigation/disinfection protocol has great importance on prognosis. OBJECTIVE: The present study evaluated the antibacterial efficiency of Endosafe (Orangedental GmbH & Co. KG), photo-activated disinfection (PAD; Orangedental GmbH & Co. KG), diode laser (Epic 10; Biolase, Inc.), ozone (O3, Ozonytron; Biozonix, München, Germany), and sodium hypochloride applications in primary root canals that were infected with Enterococcus faecalis after standard mechanical instrumentation. METHODS: The study was conducted on roots of 100 human primary molar teeth, which were extracted due to excessive caries. The roots were divided in 5 groups with 15 roots in each root disinfection protocol. In addition, 15 samples and 10 samples served as positive and negative controls, respectively. The Shapiro-Wilk test, the Kruskal-Wallis test and then by post hoc group comparisons with the Bonferroni-adjusted Mann-Whitney U test (unpaired observations) was used. RESULTS: Sodium hypochlorite (NaOCl) exhibited the highest antibacterial effect (0 colony-forming units per mL). Diode laser irradiation was statistically more effective than the ozone, PAD, and Endosafe groups (p < 0.001). Endosafe, PAD, and ozone groups showed similar antibacterial effect (p > 0.05). Although not statistically significant, the Endosafe was more effective in reducing the bacterial count when compared with ozone and PAD. CONCLUSIONS: The five tested irrigation systems were shown to be effective in disinfection of the E. faecalis-contaminated primary root canals and best results were obtained with 2.5% NaOCl and diode laser.

Age of majority assessment in Dutch individuals based on Cameriere's third molar maturity index.

Radiological examination of the third molar is done in living individuals for estimation of chronological age, especially in the late adolescence. The aim of this study was to assess the application of Cameriere's third molar maturity index (I3M) to determine whether an individual is 18 years or older (adult) or younger than 18 years (minor) in a sample of Dutch individuals. The sample consisted of panoramic images of 360 individuals aged between 14 and 22 years old. Three observers performed the measurements. Gender was not statistically significant in discriminating adults and minors. The highest value of the Youden index of the receiver operating curve analysis was for the value of I3M<0.08 in discriminating individuals as minor or adult. The specificity (Sp) and sensitivity (Se) results for females were 96.3% and 72.7% respectively. The Sp and Se for males were 95.0% and 84.0% respectively. The probabilities of correctly classified individuals were 83.3% and 88.9%, and Bayes post-test probability was 96.3% and 95.7% in females and males respectively. Obtained results showed that the specific cut-off point of I3M<0.08 may be a useful and reliable method for adult age assessment in a Dutch population.

Microleakage beneath ceramic and metal brackets photopolymerized with LED or conventional light curing units.

OBJECTIVE: To test the null hypotheses that (1) the type of light curing unit used (quartz-tungsten-halogen [QTH] or light-emitting diode [LED]) would not affect the amount of microleakage observed beneath brackets, and (2) the bracket type used (ceramic or metal) would not influence the amount of microleakage observed beneath brackets. MATERIALS AND METHODS: 40 freshly-extracted human premolars were randomly assigned into 4 bonding groups (n = 10/group): group 1, metal bracket + LED-cured Transbond XT; group 2, ceramic bracket + LED-cured Transbond XT; group 3, metal bracket + QTH-cured Transbond XT; and group 4, ceramic bracket + QTH-cured Transbond XT. The teeth were kept in distilled water for 1 month, and thereafter subjected to 500 thermal cycles. Then, specimens were sealed with nail varnish, stained with 0.5% basic fuchsin for 24 hours, sectioned, and photographed under a stereomicroscope. Microleakage was scored with regard to the adhesive-tooth interface and the bracket-adhesive interface at both incisal and gingival margins. Statistical analysis was accomplished by Kruskal-Wallis and Mann-Whitney U-tests with Bonferroni correction. RESULTS: Microleakage was observed in all groups. When an LED curing unit was used for adhesive polymerization, ceramic brackets displayed significantly less microleakage than metal brackets in both tooth-adhesive and bracket-adhesive interfaces. When a QTH curing unit was used, ceramic brackets displayed significantly less microleakage than metal brackets in the bracket-adhesive interface in both gingival and incisal margins. CONCLUSIONS: Ceramic brackets cured with LED units were the best combination, demonstrating the lowest microleakage scores.

Microleakage beneath ceramic and metal brackets bonded with a conventional and an antibacterial adhesive system.

OBJECTIVE: To assess microleakage of a tooth-adhesive-bracket complex when metal or ceramic brackets were bonded with a conventional and an antibacterial self-etching adhesive. MATERIALS AND METHODS: Forty freshly extracted human premolars were randomly assigned to four equal groups and received the following treatments: group 1 = Transbond XT + metal bracket, group 2 = Transbond XT + ceramic bracket, group 3 = Clearfil Protect Bond + ceramic bracket, and group 4 = Clearfil Protect Bond + metal bracket. After photopolymerization, the teeth were kept in distilled water for 1 month and thereafter subjected to thermal cycling (500 cycles). Specimens were further sealed with nail varnish, stained with 0.5% basic fuchsin for 24 hours, sectioned and examined under a stereomicroscope, and scored for marginal microleakage for the adhesive-tooth and bracket-adhesive interfaces from incisal and gingival margins. Statistical analysis was accomplished by Kruskal-Wallis test and Mann-Whitney U-test with Bonferroni correction. RESULTS: All groups demonstrated microleakage between the adhesive-enamel and bracket-adhesive interfaces. A significant difference was observed among all groups (P < .05) for the microleakage between the bracket-adhesive interface. Metal brackets exhibited significantly more microleakage than did ceramic brackets between the bracket-adhesive interface with either of the adhesives. Clearfil Protect Bond exhibited results similar to Transbond XT. Clearfil Protect Bond may be a choice of adhesive in bracket bonding because of its antibacterial activity and similar microleakage results with the orthodontic adhesive. CONCLUSIONS: Metal brackets cause more leakage between an adhesive-bracket interface, which may lead to lower clinical shear bond strength and white-spot lesions.

Effect of active pretreatment of self-etching primers on the ultramorphology of intact primary and permanent tooth enamel.

PURPOSE: The objective of this study was to evaluate the ultramorphological changes after agitated and nonagitated application of self-etching primer systems on unground primary and permanent enamel. METHODS: Five self-etching primer systems were used: (1) Clearfil SE Bond; (2) Clearfil Protect Bond; (3) Adper Prompt; (4) Xeno III; and (5) nonrinse conditioner (NRC). Noncarious human primary and permanent incisors were collected and stored frozen until used. Intact labial surfaces were divided into 2 halves, applying the self-etching primers with (active application) and without (inactive agitation) using a microbrush within the times recommended by the manufacturers. Treated surfaces were further processed for ultramorphological evaluation under scanning electron microscope (SEM). RESULTS: All tested self-etching systems produced weaker etch patterns and less dissolution of enamel surface compared with acid-etched samples in both primary and permanent teeth. Except for NRC and Adper Prompt, agitation of the surface did not increase the etching efficacy. Clearfil SE Bond and Clearfil Protect Bond resulted in similar morphological features following application in either mode. CONCLUSION: While agitation of self-etching primers may improve etching efficacy, this effect appears to be dependent on the material used. Phosphoric acid produces well-defined etching patterns on intact primary and permanent enamel.

Effects of music on sedation depth and sedative use during pediatric dental procedures.

STUDY OBJECTIVE: The study aimed to investigate the effects of listening to music or providing sound isolation on the depth of sedation and need for sedatives in pediatric dental patients. DESIGN: Prospective, randomized, and controlled study. SETTING: Tertiary, university hospital. PATIENTS: In total, 180 pediatric patients, American Society of Anesthesiologists physical status I and II, who were scheduled for dental procedures of tooth extraction, filling, amputation, and root treatment. INTERVENTIONS: Patients were categorized into 3 groups: music, isolation, and control. During the procedures, the patients in the music group listened to Vivaldi's The Four Seasons violin concertos by sound-isolating headphones, whereas the patients in the isolation group wore the headphones but did not listen to music. All patients were sedated by 0.1 mg/kg midazolam and 1 mg/kg propofol. During the procedure, an additional 0.5 mg/kg propofol was administered as required. MEASUREMENTS AND MAIN RESULTS: Bispectral index was used for quantifying the depth of sedation, and total dosage of the propofol was used for sedative requirements. The patients' heart rates, oxygen saturations, and Observer's Assessment of Alertness and Sedation Scale and bispectral index scores, which were monitored during the operation, were similar among the groups. In terms of the amount of propofol used, the groups were similar. Prolonged postoperative recovery cases were found to be significantly frequent in the control group, according to the recovery duration measurements (P = .004). CONCLUSIONS: Listening to music or providing sound isolation during pediatric dental interventions did not alter the sedation level, amount of medication, and hemodynamic variables significantly. This result might be due to the deep sedation levels reached during the procedures. However, listening to music and providing sound isolation might have contributed in shortening the postoperative recovery duration of the patients.

Dental and dentofacial problems in a female child with Toriello-Carey -syndrome: changes in 3 years.

Toriello-Carey syndrome is a rare disease whose clinical manifestations are midline facial defects, laryngeal and pharyngeal hypoplasia, cardiac defect, and corpus callosum hypoplasia. Literature states that clinical manifestations are more evident in males. This is the second report in the literature which describes the dental and dentofacial -features in an 8-year-old female patient with Toriello-Carey syndrome.

Resin composite repair: Quantitative microleakage evaluation of resin-resin and resin-tooth interfaces with different surface treatments.

OBJECTIVE: The aim was to evaluate the effect of different adhesive systems and surface treatments on the integrity of resin-resin and resin-tooth interfaces after partial removal of preexisting resin composites using quantitative image analysis for microleakage testing protocol. MATERIALS AND METHODS: A total of 80 human molar teeth were restored with either of the resin composites (Filtek Z250/GrandioSO) occlusally. The teeth were thermocycled (1000×). Mesial and distal 1/3 parts of the restorations were removed out leaving only middle part. One side of the cavity was finished with course diamond bur and the other was air-abraded with 50 µm Al2O3. They were randomly divided into four groups (n = 10) to receive: Group 1: Adper Single Bond 2; Group 2: All Bond 3; Group 3: ClearfilSE; Group 4: BeautiBond, before being repaired with the same resin composite (Filtek Z250). The specimens were re-thermocycled (1000×), sealed with nail varnish, stained with 0.5% basic fuchsin, sectioned mesiodistally and photographed digitally. The extent of dye penetration was measured by image analysis software (ImageJ) for both bur-finished and air-abraded surfaces at resin-tooth and resin-resin interfaces. The data were analyzed statistically. RESULTS: BeautiBond exhibited the most microleakage at every site. Irrespective of adhesive and initial composite type, air-abrasion showed less microleakage except for BeautiBond. The type of initial repaired restorative material did not affect the microleakage. BeautiBond adhesive may not be preferred in resin composite repair in terms of microleakage prevention. CONCLUSIONS: Surface treatment with air-abrasion produced the lowest microleakage scores, independent of the adhesive systems and the pre-existing resin composite type. Pre-existing composite type does not affect the microleakage issue. All-in-one adhesive resin (BeautiBond) may not be preferred in resin composite repair in terms of microleakage prevention.

Do adhesive systems leave resin coats on the surfaces of the metal matrix bands? An adhesive remnant characterization.

Reestablishing proximal contacts with composite resins may prove challenging since the applied adhesives may lead to resin coating that produces additional thickness. The aim of this study was to investigate the surface of metal matrix bands after application of adhesive systems and blowing or wiping off the adhesive before polymerization. Seventeen groups of matrix bands were prepared. The remnant particles were characterized by energy dispersive spectrum and scanning electron microscopy. Total etch and two-step self-etch adhesives did not leave any resin residues by wiping and blowing off. All-in-one adhesive revealed resin residues despite wiping off. Prime and Bond NT did not leave any remnant with compomer. Clinicians must be made aware of the consequences of possible adhesive remnants on matrix bands that may lead to a defective definitive restoration. The adhesive resin used for Class II restorations may leave resin coats on metal matrix bands after polymerization, resulting in additional thickness on the metal matrix bands and poor quality of the proximal surface of the definitive restoration when the adhesive system is incorporated in the restoration.

Microleakage of newly developed glass carbomer cement in primary teeth.

OBJECTIVE: Glass carbomer cement represents a new generation of dental material, which mineralizes gradually into fluorapatite. The aim of this study was to evaluate the microleakage and marginal integrity of newly developed glass carbomer cement with and without protective surface coating (SC) in primary molars. METHODS: Standardized cavities were prepared on extracted human primary molars, and the teeth were randomly assigned into the following groups (n = 10/each): (1) conventional glass ionomer cement (GIC) without SC; (2) GIC with SC; (3) glass carbomer cement without SC; (4) glass carbomer cement with SC; and (5) compomer without SC. Following thermocycling (5 ± 2°C-55 ± 2°C, dwell time 15 s, 2000×), the specimens were immersed in 0.5% basic fuchsin solution, sectioned, and digitally photographed. Microleakage was evaluated quantitatively by using open-source image analysis toolkit (ImageJ), and the data were analyzed statistically by using Kruskal-Wallis and Conover's Multiple Comparison tests (P=.05). RESULTS: The greatest amount of dye leakage was observed in the uncoated glass carbomer specimens, followed by the uncoated glass ionomer group (P<.05). There was no significant difference between the microleakage values of coated glass ionomer, coated glass carbomer, and the compomer (P>.05). The following statistical ranking was observed among microleakage of the test materials: uncoated glass carbomer > uncoated glass ionomer > coated glass ionomer ≈ coated glass carbomer ≈ compomer. Uncoated glass carbomer exhibited severe internal ice crack-like lines. CONCLUSION: The use of the new glass carbomer cement without SC results in severe microleakage and catastrophic internal cracks.

The effects of prophylactic ozone pretreatment of enamel on shear bond strength of orthodontic brackets bonded with total or self-etch adhesive systems.

OBJECTIVES: The aim of this in vitro study is to determine (1) shear bond strength (SBS) of brackets bonded with self-etch and total-etch adhesive after ozone treatment (2) bond failure interface using a modified Adhesive Remnant Index (ARI). METHODS: 52 premolars were randomly assigned into four groups (n=13) and received the following treatments: Group 1: 30 s Ozone (Biozonix, Ozonytron, Vehos Medikal, Ankara, Turkey) application + Transbond Plus Self-Etching Primer (SEP) (3M) + Transbond XT (3M), Group 2: Transbond Plus SEP + Transbond XT, Group 3: 30 s Ozone application + 37% orthophosphoric acid + Transbond XT Primer (3M) + Transbond XT, Group 4: 37% orthophosphoric acid + Transbond XT Primer + Transbond XT. All samples were stored in deionised water at 37°C for 24 hours. Shear debonding test was performed by applying a vertical force to the base of the bracket at a cross-head speed of 1 mm/min. RESULTS: The mean SBS results were Group 1: 10.48 MPa; Group 2: 8.89 MPa; Group 3: 9.41 MPa; Group 4: 9.82 MPa. One-Way Variance Test revealed that the difference between the groups was not statistically significant (P=0.267). Debonded brackets were examined by an optical microscope at X16 magnification to determine the bond failure interface using a modified ARI. The results were (mean) Group 1: 2.38; Group 2: 1.31; Group 3: 3.00; Group 4: 1.92. Multiple comparisons showed that Groups 1 and 2, 2 and 3, 3 and 4 were statistically different (P=0.014, P<.001 and P=0.025). CONCLUSIONS: Ozone treatment prior to bracket bonding does not affect the shear bond strength.

Effect of LED curing on marginal integrity of an ormocer-based sealant.

PURPOSE: The purpose of this study was to investigate the microleakage of a light cured, ormocer-based fissure sealant when photopolymerized with 2 different light emitting diode (LED) curing units and a conventional quartz-tungsten halogen (QTH) light-curing unit. METHODS: Thirty freshly extracted, unerupted human third molars from 9 adolescent were randomly assigned into 3 groups (N=10/group). Pits and fissures were acid etched for 30 seconds, rinsed for 15 seconds with an air-water spray, and air-dried. An ormocer-based fissure sealant material (Admira Seal) was applied to all fissures. In group 1, the sealant was photopolymerized with a Smart Light LED curing unit (Dentsply) for 10 seconds. Another LED curing unit (Elipar II) and a conventional QTH curing unit (Hilux) were used in groups 2 and 3 for 10 and 30 seconds, respectively. Specimens were immersed in 0.5% basic fuchsin for 24 hours, sectioned and examined under a stereomicroscope, and scored for marginal microleakage. RESULTS: Statistical analysis of microleakage scores revealed no significant difference among the groups tested (P>.05, Kruskal-Wallis test). CONCLUSION: The tested LED curing units may provide reduction in total application time without comprising marginal integrity of the ormocer-based sealant.

The effects of one-step self-etch adhesives on the induction of oxidative stress and production of TGF-beta1 and BMP-2 by human gingival fibroblasts.

The aim of this study was to evaluate and compare the effects of two self-etch adhesive materials on the induction of oxidative stress and production of transforming growth factor-beta1 (TGF-beta1) and bone morphogenetic protein-2 (BMP-2) by cultured human gingival fibroblasts (HGF). Inflammation-free attached gingiva was obtained from healthy donors under informed consent. Following 24- and 72-h exposure of HGF to two different elutes of the test materials, cell viability was determined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Lipid peroxidation, a major indicator of oxidative stress, was measured by the thiobarbituric acid reactive substance (TBARS) assay. TGF-beta1 and BMP-2 levels in cell-free culture media were determined by enzyme-linked immunosorbent assay (ELISA). Cell viability of the test groups was significantly lower than those of control at 24 and 72 h (P < 0.001), but showed an increase at 72 h (P < 0.001). The TBARS levels of both test groups were significantly greater than that of control (P < 0.05), and displayed similar values at 72 h (P > 0.05). For both materials, the levels of TGF-beta1 and BMP-2 were significantly greater than that of control (P < 0.05). Both test groups showed increased TGF-beta1 levels. These results indicate that the tested self-etch adhesives might be capable of inducing production of TGF-beta1 and BMP-2 in cultured HGF, despite their cytotoxic and oxidative stress-producing potential.