Can a Self-etching Primer be Effective in Bonding Aligner Attachments to Different Types of Ceramics?

Objective: This in vitro study aimed to evaluate the effectiveness of pretreatment with a self-etching primer for bonding aligner attachments to lithium disilicate (LD) and monolithic zirconia (MZ) ceramics. Methods: Forty ceramics, including LD (n=20) and MZ (n=20), were divided into four study groups according to the surface pretreatments: LD specimens pretreated with universal primer (Monobond Plus, MP) after hydrofluoric acid etching (Group 1); MZ ceramics pretreated with MP after sandblasting (Group 2); LD ceramics pretreated with self-etching ceramic primer (Monobond etch & prime, MEP) (Group 3); and MZ ceramics pretreated with MEP after sandblasting (Group 4). The aligner composite (GC Aligner Connect) and universal adhesive (GPremio Bond) were used to prepare the resin attachments. The bond strength was evaluated by micro-shear bond strength (SBS) testing (0.1 mm/min) after thermocycling, and the remnant adhesive was scored according to the resin attachment remnant index (RARI). The SBS data were analyzed using ANOVA and Tukey tests, and the RARI scores were analyzed using the chi-square test. Results: Group 1 had the lowest SBS, and group 2 had the highest SBS. There were significant differences between the groups in terms of bond strength (p<0.05). The RARI scores showed no significant differences, regardless of the pretreatment and ceramic type. Conclusion: The use of a self-etching primer increased the bond strength of resin attachments on LD ceramics. For zirconia ceramics, both ceramic primers are recommended for aligner attachment bonding.

Effects of Different Combinations of Er:YAG Laser-Adhesives on Enamel Demineralization and Bracket Bond Strength.

OBJECTIVE: The purpose of this study was to investigate the demineralization around brackets and shear bond strength (SBS) of brackets bonded to Er:YAG laser-irradiated enamel at different power settings with various adhesive systems combinations. METHODS: A total of 108 premolar teeth were used in this study. Teeth were assigned into three groups according to the etching procedure, then each group divided into three subgroups based on the application of different adhesive systems. There were a total of nine groups as follows. Group 1: Acid + Transbond XT Primer; group 2: Er:YAG (100 mJ, 10 Hz) etching + Transbond XT Primer; group 3: Er:YAG (200 mJ, 10 Hz) etching + Transbond XT Primer; group 4: Transbond Plus self-etching primer (SEP); group 5: Er:YAG (100 mJ, 10 Hz) etching + Transbond Plus SEP; group 6: Er:YAG (200 mJ, 10 Hz) etching + Transbond Plus SEP; group 7: Clearfil Protect Bond; group 8: Er:YAG (100 mJ, 10 Hz) etching + Clearfil Protect Bond; group 9: Er:YAG (200 mJ, 10 Hz) etching + Clearfil Protect Bond. Brackets were bonded with Transbond XT Adhesive Paste in all groups. Teeth to be evaluated for demineralization and SBS were exposed to pH and thermal cyclings, respectively. Then, demineralization samples were scanned with micro-CT to determine lesion depth values. For SBS test, a universal testing machine was used and adhesive remnant was index scored after debonding. Data were analyzed statistically. RESULTS: No significant differences were found among the lesion depth values of the various groups, except for G7 and G8, in which the lowest values were recorded. The lowest SBS values were in G7, whereas the highest were in G9. The differences between the other groups were not significant. CONCLUSIONS: Er:YAG laser did not have a positive effect on prevention of enamel demineralization. When two step self-etch adhesive is preferred for bonding brackets, laser etching at 1 W (100 mJ, 10 Hz) is suggested to improve SBS of brackets.

Do Different Orthodontic Malocclusions Affect Patients' Self-Concept and Psychosocial Status?

OBJECTIVE: The aim of this study was to evaluate the self-concept and psychosocial status measured by the levels of social phobia and loneliness in a sample of adolescent patients with different malocclusions and to explain the relationships, if any, between malocclusions. METHODS: This study was performed on 90 (41 females and 49 males) orthodontic patients with a mean age of 13.52±1.81 years. The patients were divided into three groups (Class I, Class II, and Class III) according to the different types of malocclusions. Piers-Harris Children's Self-Concept Scale (PHCSCS) was used to determine the self-concepts of patients. In addition, the levels of social phobia and loneliness were measured by Capa Social Phobia Scale for Children and Adolescents (CSPSCA) and University of California Los Angeles (UCLA) Loneliness Inventory, respectively. Data were analyzed statistically. The self-concept, social phobia, and loneliness scores of each group were compared using two-way analysis of variance (ANOVA) and Tukey's post hoc test. RESULTS: Self-concept scores did not significantly differ between the groups, except for the popularity subscale. Patients with Class II malocclusion had the lowest popularity scores. No significant differences were found between the levels of social phobia and loneliness among groups (p>0.05). CONCLUSION: Our findings demonstrated that different malocclusions do not affect patients' self-concept and psychosocial well-being.

A reliable method for evaluating upper molar distalization: Superimposition of three-dimensional digital models.

OBJECTIVE: The aim of this study was to evaluate the reliability of measurements obtained after the superimposition of three-dimensional (3D) digital models by comparing them with those obtained from lateral cephalometric radiographs and photocopies of plaster models for the evaluation of upper molar distalization. METHODS: Data were collected from plaster models and lateral cephalometric radiographs of 20 Class II patients whose maxillary first molars were distalized with an intraoral distalizer. The posterior movements of the maxillary first molars were evaluated using lateral cephalometric radiographs (group CP), photocopies of plaster models (group PH), and digitized 3D models (group TD). Additionally, distalization and expansion of the other teeth and the degrees of molar rotation were measured in group PH and group TD and compared between the two groups. RESULTS: No significant difference was observed regarding the amount of molar distalization among the three groups. A comparison of the aforementioned parameters between group PH and group TD did not reveal any significant difference. CONCLUSIONS: 3D digital models are reliable to assess the results of upper molar distalization and can be considered a valid alternative to conventional measurement methods.

Effect of bracket type on halitosis, periodontal status, and microbial colonization.

OBJECTIVE: To determine the effect of bracket type on halitosis, periodontal status, and microbial colonization. MATERIALS AND METHODS: Forty-six patients scheduled for fixed orthodontic treatment (age 11-16 years) were selected from the orthodontic department of Suleyman Demirel University. Patients were divided into two groups with random distribution of brackets; 23 patients were treated with self-ligating brackets (group SLBs), the others with conventional brackets (group CBs). Halitosis measurements and periodontal and microbial records were obtained before the placement of brackets (T0), 1 week later (T1), and 5 weeks after bonding (T2). Periodontal parameters, including plaque index (PI), gingival index (GI), and bleeding on probing index (BOP), were obtained from all the bonded teeth. Halitosis measurements were performed at the same time. Microbial samples were obtained from the buccal surfaces of all the bonded teeth. Data were analyzed by using a repeated-measurement analysis of variance test for the comparison of parameters between groups and times. RESULTS: Periodontal parameters and halitosis results were higher in the CBs group than in the SLBs group (P<.05). In the SLBs group, halitosis and BOP values revealed no pronounced changes between T1 and T2 (P>.05). Intra- and intergroup comparisons showed that there were no statistically significant differences for microbial colonization between all the time intervals (P>.05). CONCLUSION: Bracket type has an effect on halitosis and periodontal status. Therefore, self-ligating brackets may be advised in order to prevent patients from developing halitosis and to increase the likelihood of good oral hygiene during orthodontic treatment.

Systemic propolis stimulates new bone formation at the expanded suture: a histomorphometric study.

OBJECTIVE: To investigate the effects of systemically given propolis on the expanded premaxillary suture in a rat study model. MATERIALS AND METHODS: The 24 rats were randomly divided into three groups-only expansion (OE), expansion plus propolis (PRO), and nonexpansion (control) groups. After the 5-day expansion period was completed, the OE and PRO groups underwent 12 days of mechanical retention. At the end of this period, the animals were euthanatized and their pre-maxillae were dissected and fixed. Histomorphometric examination was performed to determine the number of osteoclasts, osteoblasts, and capillaries as well as the intensity of inflammatory cells and amount of new bone formation. RESULTS: Statistical analysis showed that the intensities of inflammatory cells, number of osteoblasts, and amount of new bone formation were greater in the PRO group than in the other groups. The PRO group also had more osteoclasts and new capillaries. CONCLUSION: Systemic use of propolis may hasten new bone formation at the expanded suture in rats.

Lasers in orthodontics.

Many types of dental lasers are currently available that can be efficiently used for soft and hard tissue applications in the field of orthodontics. For achieving the desired effects in the target tissue, knowledge of laser characteristics such as power, wavelength and timing, is necessary. Laser therapy is advantageous because it often avoids bleeding, can be pain free, is non-invasive and is relatively quick. The high cost is its primary disadvantage. It is very important to take the necessary precautions to prevent possible tissue damage when using laser dental systems. Here, we reviewed the main types and characteristics of laser systems used in dental practice and discuss the applications of lasers in orthodontics, harmful effects and laser system safety.

Comparison of Bolton analysis and tooth size measurements obtained using conventional and three-dimensional orthodontic models.

OBJECTIVES: The aim of this study was to compare the accuracy, reproducibility, efficacy and effectiveness of measurements obtained using digital models with those obtained using plaster models. MATERIALS AND METHODS: A total of 20 digital models were produced by the Ortho Three-dimensional Models (O3DM) Laboratory and their software (O3DM version 2) was used to obtain measurements. Identical plaster models were used to obtain measurements of teeth with a vernier caliper. The maximum mesiodistal width of each study model, from first molar to first molar, was measured. All measurements were repeated at least 1 month later by the same operator for both digital and manual methods. The data were analyzed using Cronbach α, Wilcoxon signed rank test and the McNemar test. RESULTS: Cronbach α value of the data at T1 and T2 for 6 anterior and 12 overall teeth measured using the two methods was very close to the ideal value of 1, indicating high intra-observer reliability. The Wilcoxon signed rank test showed statistically significant differences between the two methods (P = 0.000, P < 0.001). The measurements obtained using the digital models were lower than those obtained using the plaster models. No statistically significant differences were found between the two methods for anterior Bolton discrepancies (P = 0.375) or overall Bolton discrepancies (P = 0.00). Paired comparisons of repeated measurements for Bolton ratios showed no statistically significant differences for anterior or overall Bolton discrepancies (P = 0.688 and P = 0.375, respectively). CONCLUSIONS: Use of O3DM software is an acceptable alternative to the traditional vernier caliper method in orthodontic practice.

The relationship of orthodontic treatment need with periodontal status, dental caries, and sociodemographic factors.

The aim of this study was to determine the relationship of orthodontic malocclusion with periodontal status, dental caries, and sociodemographic status. Our study population consisted of a sample of 836 school children (384 male and 452 female, aged 11-14 years). Four experienced orthodontists and two experienced periodontists performed the clinical examinations. The Treatment Priority Index (TPI), Community Periodontal Index of Treatment Needs (CPITN), decayed, missing, filled teeth (DMFT) scores, and a questionnaire that surveyed socio-demographic status of students were used. Spearman's rank correlation coefficients were used to measure the association between variables. TPI scores showed that 36.4% of the students had normal occlusion, while 41.2% had slight, 15.7% had definite, 4% had severe, and 2.7% had very severe malocclusion. TPI values did not show any significant differences between pupils in different age, gender, socioeconomic status groups, and CPITN scores, whereas there was a significant relationship between TPI and DMFT scores. The orthodontic treatment need was not significantly correlated with CPITN or socio-demographic status; however, the correlation coefficient showed a significant relationship between TPI and DMFT scores.

Comparison of retention characteristics of Essix and Hawley retainers.

OBJECTIVE: We aimed to compare the retention characteristics of Essix and Hawley retainers. METHODS: Adolescents undergoing fixed appliance treatment at 2 centers were recruited for this study. Twenty-two patients (16 women and 6 men) wore Essix retainers (Essix group) while 20 (14 women and 6 men) wore Hawley retainers (Hawley group). The mean retention time was 1 year, and the mean follow-up recall time for both groups was 2 years. Two qualified dental examiners evaluated the blind patient data. Maxillary and mandibular dental casts and lateral cephalograms were analyzed at 4 stages: pretreatment (T1), post-treatment (T2), post-retention (T3), and follow-up (T4). RESULTS: The results revealed that Essix appliances were more efficient in retaining the anterior teeth in the mandible during a 1-year retention period. The irregularity index increased in both arches in both groups after a 2-year post-retention period. The mandibular arch lengths increased during treatment and tended to return to their original value after retention in both groups; however, these changes were statistically significant only in the Hawley group. Cephalometric variables did not show any significant differences. CONCLUSIONS: The retention characteristics of both Essix and Hawley retainers are similar.

Oxidative imbalance and anxiety in patients with sleep bruxism.

OBJECTIVE: We evaluated the relationship among sleep bruxism (SB), antioxidant/oxidant status, and anxiety level to determine whether antioxidant/oxidant status may be used as a biological marker of SB. STUDY DESIGN: Thirty-three SB and 32 healthy patients of similar age, sex, and body mass index were enrolled, venous blood was collected, and anxiety scores were determined. Plasma samples were analyzed for total oxidant status, antioxidant status, and oxidative stress index. RESULTS: In 2 of the 3 assays performed, SB patients exhibited an oxidative imbalance. A higher anxiety score was observed with SB (P < 0.05). CONCLUSIONS: These results show that oxidant/antioxidant imbalance may be related to SB, either pathophysiologically or as an outcome of the condition. Further biochemical studies could prove useful in determining the importance of antioxidant drugs in the treatment of SB.

Effects of Ginkgo biloba on experimental rapid maxillary expansion model: a histomorphometric study.

OBJECTIVE: We aimed to investigate the effect of systemic Ginkgo biloba in rapid maxillary expansion (RME). STUDY DESIGN: We randomly divided 24 rats into 3 groups: expansion only (EO), expansion plus Ginkgo biloba (GB), and no expansion (NE). Expansion appliances were affixed to the maxillary incisors. After a 5-day expansion period, there was a consolidation period of 15 days, following which the rats were killed. Histomorphometric examination was performed to determine the number of osteoclasts, osteoblasts, and capillaries, the number and intensity of inflammatory cells, and new bone formation. RESULTS: New bone formation, number of capillaries, and the ratio of inflammatory cells in maxillary sutures were higher in the GB group than in the other groups. Statistical analysis demonstrated that the GB group had more osteoblasts and osteoclasts than the other groups. CONCLUSIONS: GB may hasten new bone regeneration in RME and prevent relapse after RME.

Effect of fixed appliances on oral malodor.

INTRODUCTION: The objective of this study was to evaluate the effect of fixed appliances on oral malodor. METHODS: Forty-one patients participated in this study. They were randomized into 2 groups: treated with fixed orthodontic appliances and untreated controls. Oral malodor measurements and the gingival and plaque indexes were recorded in each group by same periodontist. Measurements were taken from the study group before bonding, 1 week after bonding, and 4 weeks after bonding. The control group's measurements were made at the same time. RESULTS: Oral malodor and the gingival and plaque indexes were significantly increased 1 week after bonding (P <0.05). Oral malodor was increased at 4 weeks after bonding (P >0.05). The comparison of the groups showed differences 1 week and 4 weeks after bonding. CONCLUSIONS: The oral malodor reached the critical level during fixed orthodontic treatment. Oral malodor could indicate a need to evaluate oral health and remind patients of the importance of maintaining ideal oral hygiene.

Shear Bond Strength of Orthodontic Brackets Cured with Different Light Sources under Thermocycling.

OBJECTIVES: The aim of this study was to compare the shear bond strength (SBS) of two different light sources under different thermal cycle frequencies. METHODS: Ninety human premolar teeth were divided into six groups, in which three groups consisted of halogen groups - Group I was cured with halogen without thermocycle, Group II cured with halogen with 500 thermocycles, and Group III cured with halogen with 10,000 thermocycles. The other three groups consisted of Plasma arc (PAC) group - Group IV was cured with PAC without thermocycle, Group V cured with PAC thermocycled 500 cycles, and Group VI cured with PAC thermocycled 10,000 cycles. Two way ANOVA was used to compare the SBS between the groups, and chi square-test was used to compare the bond failure of ARI scores among the groups. RESULTS: A significant difference was found for curing lights (P<.001) and thermocycling (P<.01). However, there was no interaction between light curing and thermocycling (P=.177). The halogen groups demonstrated higher mean SBS than the PAC groups. Both groups showed a significant reduction between no cycles and 10,000 cycles (P<.05). CONCLUSIONS: Both light sources showed favorable SBS performance without the thermocycle procedure. Thermocycling significantly decreased the SBS values of both groups.

Oral and nasal malodor in patients with and without cleft lip and palate who had undergone orthodontic therapy.

OBJECTIVE: To compare oral and nasal malodor in patients with and without cleft lip and palate (CLP) who had undergone orthodontic therapy. SETTING: University of Cumhuriyet, Sivas, Turkey. PATIENTS: The study included 33 patients. Group 1 was composed of 11 patients with CLP. Measurements were taken while they were undergoing treatment with orthodontic fixed appliances. Group 2 included 11 individuals without CLP; measurements were taken during fixed orthodontic therapy. Group 3 consisted of 11 individuals without CLP who did not receive orthodontic therapy. INTERVENTION: Oral malodor, nasal malodor, Gingival Index, Plaque Index, and probing depths were evaluated in each group. RESULTS: Plaque Index, Gingival Index, and probing depths showed no significant differences between groups 1 and 2. In contrast, oral malodor was significantly different between the two groups (p < .05). Groups 2 and 3 showed differences in gingival and plaque indices but not in probing depths and oral malodor. All healthy nostrils in Group 1, Group 2, and Group 3 were significantly different from affected nostrils in the CLP patients. There was significant malodor in affected nostrils when compared with nonaffected nostrils in group 1 (p < .05). CONCLUSION: Oral malodor was increased in patients with CLP. Nasal malodor level was also higher in affected nostrils of the CLP patients compared to nostrils of healthy subjects.