The Effect of Enamel Etching with Different Acids on the Bond Strength of Brackets

The purpose of this study was to compare the bond strengths of metallic brackets on human enamel etched with different acid solutions including (1) 37% phosphoric acid, (2) 10% maleic acid, (3) 37% phosphoric acid with i.23% NaF addition, (4) 10% maleic acid with 1.23% NaF addition to reveal if this caries prevention modalities adversely affect the clinical success of bonding procedure. All the groups had stainless steel brackets bonded to the buccal surface of each tooth with no-mix adhesive. An Instron testine machine was used to determine tensile bond strengths. The mean bond strength values of the groups were as follows: phosphoric acid group 9.17 ± 4.59 MPa; maleic acid group 8.46 ± 3.89 MPa; NaF added phosphoric acid group 2.33 ±2.19 MPa; NaF added maleic acid group 2.02 ± 1.43 MPa. The statistical analysis was done by an analysis of variance and Duncan multiple range tests. Bond strengths that the two “only acid” groups yie fded were significantly higher than NaF added groups (P0.05). The current findings indicate that 10% maleic acid alone may produce similar bond strengths to 37% phosphoric acid however, 1.23% NaF addition to either phosphoric or maleic acids to increase caries resistance results in significantly lower bond strengths and should not be advocated for clinical use as an enamel conditioner

Long-Term Follow-Up of Two-Phase Orthodontic Treatment of Class II Malocclusions

Aim:The aim of the study was to investigate the stability of dentoskeletal changes 8 years after treatment with the activator appliance, followed by an edgewise appliance.Subjects and Methods:The study comprised 18 children (10 boys and 8 girls at 12.2±1.4 years of age) with a skeletal Class II pattern and a Class II molar relationship. Pre-treatment (T1) their ANB angles were greater than 4 degrees and overjets greater than 7 mm. Standardized lateral cephalograms were taken in centric occlusion at the start of treatment (T1), at the end of activator treatment (T2), at the end of fixed appliance therapy (T3) and 6.2 years after the removal of the fixed appliances (T4). Ten angular and nine linear cephalometric measurements were determined. A paired-sample t-test was used to evaluate the treatment changes.Results:At the end of active treatment period (T3) the skeletal relationship was improved and there were significant (p=0.000) increases in maxillary and mandibular length (Co-A and Co-Gn) and SNB. The upper incisors were significantly (p=0.023) uprighted and retruded (U1-NA). SNA and ANB angles were significantly (p=0.012, p=0.000 respectively) decreased whereas IMPA and mandibular plane angle (Go-Gn-SN) remained stable. At (T4) the changes were generally in agreement with those T3 at except for a slight return to the original values for SNA and A to N -I FH (mm) measurements.Conclusion:The anteroposterior dentoskeletal changes obtained with the activator appliance followed by fixed edgewise appliances were demonstrated to be stable over 6.2 years

Temperature Changes of Pulp Chamber during In Vitro

The use of lasers has been suggested for orthodontists to fabricate or repair orthodontic appliances by welding metals directly in the mouth. This work aimed to evaluate the temperature changes in the pulp chamber during welding of an orthodontic wire to an orthodontic molar band using Nd : YAG laser in vitro. A freshly extracted human third molar with eliminated pulpal tissues was used. J-type thermocouple wire was positioned in the pulp chamber. A conductor gel was used in the transferring of outside temperature changes to the thermocouple wire. An orthodontic band was applied to the molar tooth and bonded using light cured orthodontic cement. Twenty five mm length of 0.6 mm diameter orthodontic stainless steel wires was welded to the orthodontic band using Nd : YAG laser operated at 9.4 watt. Temperature variation was determined as the change from baseline temperature to the highest temperature was recorded during welding. The recorded temperature changes were between 1.8 and 6.8°C (mean: 3.3 ± 1.1°C). The reported critical 5.5°C level was exceeded in only one sample. The results of this study suggest that intraoral use of lasers holds great potential for the future of orthodontics and does not present a thermal risk. Further studies with larger samples and structural analysis are required

Natural head position and lower incisor irregularity

Objective The aim of this study was to assess the relationship between dynamic measurements of natural head position (NHP) and lower incisor irregularity to identify potential gender differences

Effect of Orthodontic Bracket Base Structure on Shear Bond Strength

Direct bonding is the method of choice for attaching fixed orthodontic appliances. These fixed appliances are produced with various bonding bases. The present study aims to compare shear bond strengths (SBS) and fracture characteristics of the bracket adhesive interface of six different bracket base types. Standard mesh base (Ultraminitrim-Dentaurum, Germany), Supermesh base (Microarch- GAC, USA ), Integral base (Dyna-Lock, 3M Unitek, USA and Micro -loc GAC, USA), Micro-etched base (Mi -niature Twin, 3M-Unitek), and laser structured base (Discovery-Dentaurum, Germany) brackets were used. Twenty brackets of each type were bonded to specially constructed 120 bonding bases with Transbond XT (3M Unitek, USA). A testing machine (Model 500, Testometric, Lancashire, England) was used to evaluate shear bond strengths for all groups. After debonding, the amount of residual adhesive on the bracket was assessed according to the adhesive remnant index (ARI). ANOVA revealed statistically significant differences among the 6 groups tested (P<0.05). According to the results of Duncan's test highest SBS was achieved by laser treated Discovery brackets. This was followed by Micro-loc and Miniature Twin brackets. The SBS achieved by the latter two were lower but the difference with laser structured Discovery was statistically insignificant. The lowest SBS was achieved by Microarch bracket. From the results obtained in our study, we suggest that differences in bracket base design may lead to significant differences in shear bond strengths. Micro-loc, Miniature Twin or Discovery bases may be preferred to achieve higher shear bond strengths values and to reveal more accurate resin-enamel bond strength values in bond strength studies

Graduate orthodontic education in Turkey: the residents' perspective

The aim of the present study was to explore residents' perceptions of their educational and clinical treatment experiences including the number of clinical cases undertaken, patient completion rates, techniques utilised and the scientific component of Turkish graduate orthodontic programmes. Residents recorded in the list of Turkish Orthodontic Society were sent an e-mail to participate in a survey containing 46 multiple-choice questions and ten one-line answers. An e-mail with a personalised online link was sent to a total of 227 residents throughout the Turkey. Data were categorised, and basic statistics including chi-square comparative analyses were performed. A total of 136 (response rate of 59.91%) residents completed the survey. The majority of residents (58.08%) were either very satisfied' or satisfied' with their programme. Respondents said they have just the right amount of formal didactic teaching sessions or dedicated and protected academic time. Most residents (69.11%) indicated their programme offers training in numerous philosophies; whilst 97.79% said they have sufficient clinically based training and 42.64% said they have sufficient research-based training. Overall, residents in the Turkey are satisfied with their orthodontic programme. They receive comprehensive training with the opportunity to start and complete a significant number of their patients. The survey findings suggest that orthodontic programmes in Turkey are deficient in providing care to underserviced populations and disabled patients. Programmes could improve the opportunity for residents to treat patients requiring interdisciplinary treatment

Evaluation of the bond strength between aged composite cores and luting agent.

The aim of this study was to evaluate effect of different surface treatment methods on the bond strength between aged composite-resin core and luting agent

Factors Contrıbutıng To Burnout Levels Of Turkısh Orthodontısts

The aim of this study was to determine the role of gender, years of practice, academic degree, and place of employment on burnout levels of Turkish orthodontists. This study was carried out on 167 members of the Turkish Orthodontic Society who are either at private or faculty practice. Directed towards this; prepared socio-demographic information forms and "Maslach Burnout Inventory Manuals" were sent to orthodontists. Analysis of variance, Tukey HSD, Kruskal Wallis, Mann Whitney-U and t-tests were performed for statistical evaluation of received responses. Gender had no association with the burnout levels. On the other hand, place of employment, years of orthodontic practice and academic degree significantly associated one or more subscales of burnout. According to this, diminished personal accomplishment (DPA) scores were significantly higher in orthodontists at faculty practice (12.1 ±3.1) compared to private practice orthodontists (10.5+2.8). Associate Professors and orthodontists 0-15 years into the practice demonstrated more diminished personal accomplishment (DPA) scores. Depersonalization (D) scores were also higher in these groups. In general, orthodontists demonstrated less burnout in and after their early forties possibly due to increased financial satisfaction. Organizational structures such as local orthodontic societies should construct study groups in order to evaluate and eliminate causative factors of burnout in younger orthodontists. Those who are about to start a dedicated profession should be supported by local organizations in terms of guidance. New educational courses should be incorporated into curriculum of orthodontic training centers to enable the individual orthodontist to recognize self personality and to grow self-esteem