Evaluation of Implant Impression Accuracy Using Different Trays and Techniques With a 3D Superimposition Method.

PURPOSE: The purpose of this study was to evaluate the dimensional accuracy of implant impressions obtained using different tray types and techniques. MATERIALS AND METHODS: A partially dentate maxillary Kennedy Class II model was created as a reference model through three-dimensional (3D) printing. Then, 4.3-mm diameter implant analogs were placed at the first premolar, first molar, and second molar regions. Five types of trays-metal and plastic stock trays and custom trays fabricated using liquid crystal display (LCD), fused deposition modeling (FDM), and urethane dimethacrylate (UDMA) resin-were used to create impressions. Open- and closed-tray techniques were also compared. In total, 150 impressions were obtained. The reference model and impressions were scanned using a laboratory scanner. The positional and angular deviations of implants with different tray types and techniques were evaluated using the superimposition method. RESULTS: There was no statistically significant difference (P>0.05) between the impression accuracy with the different tray types and impression techniques. The angular deviations with plastic and UDMA trays were greater than those with metal, FDM, and LCD trays. Angular deviation at the second molar by using closed trays was greater than that using open plastic trays. The highest and lowest positional deviation were observed at the first molar implant with an open plastic tray impression (mean: 62.46 ± standard deviation: 28.54 µm) and a closed LCD tray impression (36.59 ± 29.93 µm). The greatest angular deviation was observed with an open FDM tray impression at the first premolar implant (0.067 ± 0.024°), and the lowest angular deviation was observed with a closed metal stock tray impression at the second molar implant (0.039 ± 0.025°). Statistical differences were detected using Mann-Whitney U tests for pair groups and the Kruskal- Wallis test for groups with more than three comparisons (P>0.05). CONCLUSION: Plastic and metal stock trays or conventional and 3D-printed custom trays can be used to obtain implant impressions for maxillary partially edentulous arches with similar dimensional accuracy. The five tray types and two techniques may be safely used to obtain impressions of partially edentulous maxillary arches with three implants.

Effect of Low-Level Laser Therapy on Peri-Miniscrew Fluid Prostaglandin E2 and Substance P Levels: A Controlled Clinical Trial.

OBJECTIVE: This study aims to evaluate the effect of low-level laser therapy on peri-miniscrew fluid prostaglandin E2 (PGE2) and substance P (SP) levels during orthodontic treatment. METHODS: A total of 15 individuals were included in this study. Miniscrews were inserted to the inter-radicular region of the maxillary right and left second premolar and the first molar teeth, and diode lasers were randomly applied to the right or left side. Irradiation was performed at 940 nm wavelength using a gallium-aluminum-arsenide diode laser with 100 mW power output, 0.125 cm2 spectral area, 8 J/cm2 energy density, and 10 seconds of exposure time. Peri-miniscrew fluid samples were collected on the 1st, 3rd, and 7th days, and PGE2 and SP levels were assessed. For statistical comparison, two-way (factors) analysis of variance with repeated measurements on one-factor levels was used at statistical significance (p) of <0.05. RESULTS: PGE2 levels on the 1st, 3rd, and 7th days were 160.64±10.05, 135.17±37.18, and 98.57±22.94, respectively, in the control group and 150.75±9.08, 87.17±40.67, and 78.10±16.50, respectively, in the laser group. SP levels on the 1st, 3rd, and 7th days were 79.90±12.05, 64.61±10.05, and 70.05±9.10, respectively, in the control group and 76.32±11.39, 60.25±9.08, and 65.71±5.59, respectively, in the laser group. The differences in PGE2 and SP levels between the laser and control groups were not statistically significant at all time intervals. CONCLUSION: Low-level laser therapy cannot be recommended as a clinical adjunct therapy to reduce inflammation and pain around the miniscrews.

Evaluation of the effects of two different indirect bonding methods on strength of the brackets in mandibular model of severe anterior crowding.

An indirect bonding method was developed to solve the problems likely to be encountered during proper positioning of the brackets. The aim of this study is to compare two different indirect bonding methods on the bond strength of the brackets. A 160 extracted human lower incisors were assigned into two groups. Transparent silicone material and bioplast material were used in transfer tray preparation in groups 1 and 2, respectively. Transbond XT adhesive system was used to bond brackets to teeth in both groups. A high intensity LED light source was used for 3 s for adhesive polymerization. Brackets were subjected to shear forces with universal test machine under 0.5 mm/min crosshead speed until failure. Adhesive Remnant Index was used to assess the amount of adhesive remnant on enamel surface after shear test under 10× magnification. Two subjects from both groups were evaluated for enamel surface characteristics with scanning electron microscope (SEM). Mean shear bond strengths were found to be 5.13 ± 1.8 MPa and 5.93 ± 2.19 MPa for silicone and bioplast groups, respectively. Bioplast group showed significantly greater shear bond strength than that of the silicone group. Maximum ARI score, assessed under ×10 magnification was 3 in both groups. A score of 3 was significantly more frequent in bioplast group. Differences were seen between the groups in terms of enamel surface characteristics under SEM evaluation. It was determined that bioplast material, which is considered to be the gold standard for the indirect bonding method, has greater shear bond strength than silicone material.

Changes in the gingival thickness and keratinized gingival width of maxillary and mandibular anterior teeth after orthodontic treatment.

OBJECTIVES: To evaluate changes in the gingival thickness (GT) and keratinized gingival width (KGW) of the maxillary and mandibular central and lateral incisors and canines after fixed orthodontic treatment and their association with sagittal tooth movement (STM). MATERIALS AND METHODS: In this study of both arches, 60 periodontally healthy subjects who had completed fixed orthodontic treatment were included. Using pretreatment and posttreatment lateral cephalograms, STM of the maxillary (1-NA angle and distance, and 1-SN angle) and mandibular (1-NB angle and distance, and IMPA angle) incisors were evaluated to divide the subjects into protrusion and retrusion groups. Pretreatment and posttreatment GT was identified via transgingival probing, and KGW was calculated from the free gingival margin to the mucogingival junction. RESULTS: The intragroup pretreatment and posttreatment comparison results showed a significant decrease in the GT of the maxillary and mandibular anterior teeth in the protrusion and retrusion groups and a decrease in the KGW of the maxillary lateral incisors in the protrusion group. Pearson correlation coefficient analyses for maxillary and mandibular anterior teeth revealed that the GT changes were not significantly associated with STM. However, a positive correlation existed between the KGW of tooth numbers 13 and 41 and STM. CONCLUSIONS: STM was not significantly associated with decreased GT of the maxillary and mandibular anterior teeth, but it was positively correlated with the KGW of tooth numbers 13 and 41.

Effects of ibuprofen and low-level laser therapy on orthodontic pain by means of the analysis of interleukin 1-beta and substance P levels in the gingival crevicular fluid.

OBJECTIVE: The goal of this study was to compare the effects of ibuprofen and low-level laser therapy in alleviating orthodontic pain observed after elastomeric separator placement (ESP) by means of the analysis of interleukin 1­beta (IL-1ß) and substance P (SP) levels in gingival crevicular fluid (GCF) and visual analog scale (VAS). MATERIALS AND METHODS: A total of 60 subjects requiring ESP for the banding of maxillary first molars were randomly assigned to the ibuprofen, laser, and control groups. The ibuprofen and control groups received, respectively, 400 mg ibuprofen and placebo lactose tablets orally 1 h before ESP; the laser group received a single low-level laser irradiation session immediately after ESP. GCF samples were collected immediately after ESP (day 0) and on days 1, 3, and 7. Pain intensity was evaluated using the VAS immediately after ESP (baseline) and at hours 2 and 6, as well as on days 1, 3, and 7. RESULTS: Although IL-1ß levels increased significantly on days 1, 3, and 7 compared to day 0, intergroup comparison results revealed insignificant differences. SP levels indicated insignificant within-group differences. Only the SP levels of the ibuprofen group showed a significant decrease on days 0 and 1 compared to the laser and control groups. In all groups, VAS scores increased from baseline to a peak level on day 1, followed by a significant decrease on days 3 and 7. Intergroup comparison results of VAS scores indicated less pain intensity in the ibuprofen group compared to the control group at baseline. CONCLUSIONS: Only the ibuprofen group exhibited significant decreases in SP levels on days 0 and 1, as well as in VAS scores at baseline.

Computerized occlusal analysis of Essix and Hawley retainers used during the retention phase: a controlled clinical trial.

AIM: The aim of this study was to evaluate the occlusal force distribution (OFD), individual tooth force (ITF), and occlusal surface area (OSA) of Essix and Hawley retainers, using T­Scan III (Tekscan Inc., South Boston, MA, USA) analysis. MATERIALS AND METHODS: A total of 35 subjects were randomly assigned to one of the retention groups following fixed orthodontic treatment. While 18 of these subjects were provided with Essix retainers, 17 were given Hawley retainers. Computerized occlusal analysis of the patients' dentitions was performed using T­Scan III. The evaluations were made after debonding (T0) and at month 3 (T1), month 6 (T2) and 1 year (T3) after the retention phase. RESULTS: The changes in OFD were significant only in the Hawley group for the left/right half jaws and the right posterior quadrants when comparing the T2-T3 time interval. Also, the differences between the groups were significant only for the left half jaw for the T0-T2 time interval and for the right half jaw when comparing the T0-T2 and the T2-T3 time intervals. The changes in ITF were insignificant within groups, but significant between the groups for tooth 11 and 22. Although there was an increase observed in OSA for both groups, the difference between the groups was insignificant. However, the OSA increase in the Essix group for the left/right anterior quadrants was significant only for the T0-T2 and the T0-T3 time intervals, while in both groups, for the posterior left quadrant, the OSA was insignificant only for the T0-T1 time interval. CONCLUSIONS: Although OSA increased when using both retention appliances, OFD did not change.

Changes in occlusal surface area and occlusal force distribution following the wear of vacuum-formed, hawley and bonded retainers: A controlled clinical trial.

To evaluate the changes in occlusal surface area (OSA) and occlusal force distribution (OFD) following the wear of Vacuum-formed (VFR), Hawley (HR) and Bonded (BR) retainers, using T-Scan III. A total of 60 subjects using three different maxillary and mandibular orthodontic retainers, VFR (n:20), HR (n:20) and BR (n:20), were included in this study. The changes in OSA and OFD were evaluated using the T-Scan III. The evaluations were made 2 hours after debonding orthodontic appliances (T0) and in the 3rd (T1) and 6th (T2) months of the retention phase. For left (LDA), right (RDA) and posterior dental arches (PDA), intragroup comparison of OSA showed significant increase in the VFR and HR groups at T1-T2 and T0-T2 time intervals and in the BR group at T0-T1 and T0-T2 time intervals. For the anterior dental arch (ADA), only the increase in the HR group at T0-T1 and T0-T2 time intervals was found significant. When compared between the groups, the changes between HR and BR groups detected at T1-T2 time interval for the RDA and at T0-T1 and T0-T2 time intervals for the ADA were found significant. Intragroup comparison of OFD displayed significant changes only in the BR group. At T0-T1 time interval, the decrease in the ADA and the increase in the PDA were found significant. Also, intergroup OFD comparison exhibited significant differences between HR and BR groups at T0-T1 time interval for ADA and PDA. Although no significant differences were found between the VFR group, the increase in OSA occurred faster in the PDA in the BR group, whereas in the ADA it was significant only in the HR group.

The thickness of posterior buccal attached gingiva at common miniscrew insertion sites in subjects with different facial types.

INTRODUCTION: The purpose of this study was to assess the thicknesses of maxillary and mandibular posterior buccal approximal attached gingiva at common miniscrew insertion sites, which has critical importance in determining miniscrew length, in subjects with different facial types. METHODS: One hundred seventy-four subjects with no transversal skeletal discrepancy were included in this study. The facial types of these subjects were evaluated in the sagittal and vertical directions. In the sagittal direction, the subjects were assigned into 3 groups: skeletal Class I, II, and III. Also, each of these groups was divided into subgroups in the vertical direction: low angle, norm, and high angle. Transgingival probing was used to measure the thickness of the buccal attached gingiva. RESULTS: The thickness of the buccal attached gingiva between the second premolar-first molar ranged from 1.18 ± 0.33 to 1.46 ± 0.28 mm and from 1.28 ± 0.30 to 1.58 ± 0.37 mm in the maxilla and mandible, respectively. The thickness of the buccal attached gingiva between the first-second molars ranged from 1.31 ± 0.41 to 1.60 ± 0.62 mm and from 1.36 ± 0.43 to 1.72 ± 0.52 mm in the maxilla and mandible, respectively. In terms of the thicknesses of the buccal attached gingiva of second premolar-first molar and first-second molars, no statistically significant difference was found between subjects with different facial types. CONCLUSIONS: It was determined that the thicknesses of maxillary and mandibular posterior buccal approximal attached gingiva varied between 1.18-1.72. At this point, the insertion of miniscrews of 7-8 mm in length was recommended for maxillary and mandibular posterior buccal regions, in order to obtain adequate insertion depth.

Gingival thicknesses of maxillary and mandibular anterior regions in subjects with different craniofacial morphologies.

INTRODUCTION: The aim of this study was to evaluate the mean gingival thicknesses of the maxillary and mandibular anterior regions in subjects with different craniofacial morphologies. METHODS: For each dental arch, 128 periodontally healthy orthodontic patients with normal values of maxillary incisor position (1/NA, angle and distance; and 1/SN, angle) and mandibular incisor position (1/NB, angle and distance; and IMPA) were enrolled in the study. Craniofacial morphology of the participants was evaluated in the sagittal (ANB angle) and vertical directions (SN/GoGn angle) on lateral cephalograms. In the sagittal direction, the subjects were divided into 3 groups as Class I, Class II, and Class III. Each group was classified as low angle, normal, or high angle in the vertical direction. Mean gingival thicknesses of the maxillary and mandibular anterior regions were determined by the ratio of the sum of gingival thickness of the relevant teeth, measured by the transgingival probing technique, to the number of teeth. RESULTS: Mean gingival thicknesses of the maxillary anterior region were 1.173 ± 0.61, 1.103 ± 0.207, and 1.130 ± 0.244 mm in the Class I, Class II, and Class III groups and 1.084 ± 0.150, 1.136 ± 0.247, and 1.159 ± 0.249 mm in the low angle, normal, and high angle groups, respectively. Mean gingival thicknesses of the mandibular anterior region were 0.710 ± 0.156, 0.741 ± 0.176, and 0.691 ± 0.157 mm in the Class I, Class II, and Class III groups and 0.705 ± 0.184, 0.701 ± 0.132, and 0.735 ± 0.174 mm in the low angle, normal, and high angle groups, respectively. No significant difference was found between the groups in terms of the mean gingival thicknesses of the maxillary and mandibular anterior regions. CONCLUSIONS: There was no significant difference between the groups in terms of the mean gingival thicknesses of the maxillary and mandibular anterior regions.

Assessment of Gingival Biotype and Keratinized Gingival Width of Maxillary Anterior Region in Individuals with Different Types of Malocclusion.

OBJECTIVE: The aim of the present study is to evaluate the relationship of gingival thickness and width of keratinized gingiva with different malocclusion groups and amount of crowding. METHODS: A total of 181 periodontally healthy subjects were enrolled in the present study. The study participants were divided into three malocclusion groups: Angle Class I, Angle Class II, and Angle Class III. Each group was divided into subgroups according to the amount of dental crowding, namely mild, moderate, and severe. The width of keratinized gingiva was calculated as the distance between mucogingival junction and free gingival margin, whereas gingival thickness was determined by a transgingival probing technique. RESULTS: Tooth numbers 13 and 23 were observed to have thin gingival biotype. The width of keratinized gingiva for tooth numbers 13 and 23 was narrower in the severe crowding group than in the moderate and mild crowding groups. The relationship of gingival thickness and width of keratinized gingiva with Angle classification was not found to be significant. CONCLUSION: Although it is thought that there is a relationship between gingival thickness, width of keratinized gingiva, and Angle classification with regard to malaligned teeth, this cross-sectional evaluation of 181 patients failed to show a significant relationship.

Long-term follow-up of enamel color changes after treatment with fixed orthodontic appliances.

INTRODUCTION: The aim of this study was the long-term follow-up of enamel color changes observed in the middle third of buccal tooth surfaces after treatment with fixed orthodontic appliances. METHODS: The study included 120 maxillary central and lateral incisors and canines of 20 subjects who had fixed orthodontic treatment. The Spectro Shade Micro device (MHT, Verona, Italy) was used to evaluate the color changes of the teeth. Measurements were made from the middle third of the buccal surfaces of the teeth after fixed orthodontic treatment and in month 3, month 6, and year 1 of the retention phase. The Commission Internationale de l'Echairage L* a* b* system that expresses the color coordinates in L*, a*, and b* symbols was used to determine the tooth color, and ΔE values between the time periods were calculated. Repeated measurement analysis of variance was used in evaluating the color changes. RESULTS: The increases in ΔL values at 3 months, 6 months, and 1 year after treatment were statistically significant, whereas they were not statistically significant from months 3 to 6, month 3 to year 1, or month 6 to year 1. The decrease in Δa and the increase in Δb values were not statistically significant. ΔE values at all time periods were statistically significant within themselves, and the greatest change was observed 1 year after treatment. ΔE values were 1.52 to 3.57, and a visible but clinically acceptable color change occurred. CONCLUSIONS: In the first 3 months, there was a significant increase in the lightness of the tooth color.

An evaluation of the gingival biotype and the width of keratinized gingiva in the mandibular anterior region of individuals with different dental malocclusion groups and levels of crowding.

OBJECTIVE: To evaluate the relationship of gingival thickness (GT) and the width of keratinized gingiva (WKG) with different malocclusion groups and the level of crowding. METHODS: A total of 187 periodontally healthy subjects (121 females and 66 males) who presented at the Faculty of Dentistry in Yüzüncü Yil University for orthodontic treatment were enrolled in the study. The individuals involved in the study were divided into three groups; Angle Class I malocclusion, Angle Class II malocclusion, and Angle Class III malocclusion. Each group was classified as mild, moderate, or severe according to the level of crowding. WKG was determined as the distance between the mucogingival junction and the free gingival margin. GT was determined by the transgingival probing technique. Factorial variance analysis and the Duncan multiple comparison test were employed to identify the extent to which a difference was apparent between the groups according to these parameters. RESULTS: It was determined that teeth in the mandibular anterior region display the thin gingival biotype. WKG and GT were observed as being higher at the mandibular incisor teeth in the severe crowding group and at the mandibular canine teeth in the mild crowding group. The GT of the mandibular right central and lateral incisors was found to be thinner in the Angle Class III group. CONCLUSIONS: Within the limits of this study, the results demonstrate that, there is no significant relationship of WKG and the mean GT in the mandibular anterior region according to the Angle classification.

Effects of Ozone and Prophylactic Antimicrobial Applications on Shear Bond Strength of Orthodontic Brackets.

OBJECTIVE: The present study aimed to evaluate the effects of ozone and prophylactic antimicrobial applications on the shear bond strengths and bond failure interfaces of orthodontic brackets. METHODS: Sixty human canine teeth were randomly divided into three groups (n=20), receiving the following treatments: Group I-pumice prophylaxis (Isler Dental, Ankara, Turkey)+37% orthophosphoric acid (Dentsply, Rio de Janeiro, Brazil)+Transbond XT primer and adhesive (3M Unitek, Monrovia, USA); Group II-prophylaxis paste (Topex, NJ, USA)+37% orthophosphoric acid (Dentsply, Rio de Janeiro, Brazil)+ Transbond XT primer and adhesive paste (3M Unitek, Monrovia, USA); and Group III-ozone application (Biozonix GmbH, Munich, Germany)+37% orthophosphoric acid (Dentsply, Rio de Janeiro, Brazil)+Transbond XT primer and adhesive (3M Unitek, Monrovia, USA). All specimens were stored at 37°C water for 24 h. Shear bond strength was assessed using a universal testing device (Autograph AGS-X; Shimadzu, Japan). Adhesive remnant index (ARI) scores were obtained through examination of teeth under stereomicroscope at 10× magnification after debonding. RESULTS: Shear bond strengths of orthodontic brackets were 16.10, 18.01, and 19.23 MPa for Groups I, II, and III, respectively. No statistically significant difference in shear bond strength of orthodontic brackets was found among the groups (p=0.273), based on Kruskal-Wallis analysis. Additionally, no significant difference was found in the ARI scores of each group using chi-square analysis (p=0.992). CONCLUSION: Shear bond strength of orthodontic brackets and ARI scores was not found to be negatively impacted by ozone application.

Morphological comparison of cervical vertebrae in adult females with different sagittal craniofacial patterns: A cross-sectional study.

INTRODUCTION: Cervical vertebral maturation (CVM) methods have gained popularity to assess growth and development status for orthodontic patients. Although craniofacial and craniocervical structures are known to be associated, there is no evidence in the literature if this relation might negatively affect the accuracy of CVM assessments. Therefore, this study aimed to comparatively investigate the sizes of the 2(nd), 3(rd), and 4(th) cervical vertebrae in adult females (radius union stage of skeletal maturity) who have different sagittal skeletal patterns. MATERIALS AND METHODS: A cross-sectional study was conducted, and 151 lateral cephalometric radiographs of adult female patients were assessed in the study. Patients were assigned to three groups according to ANB angle. Parameters including concavity depth at the lower border of the 2(nd), 3(rd), and 4(th) cervical vertebrae and base length, upper border length, body length, posterior height, anterior height, and body height of the 3(rd) and 4(th) cervical vertebrae bodies were measured. One-way analysis of variance was used for between-group comparisons. RESULTS: No statistically significant differences were found between groups in terms of concavity depth at the lower borders of the 2(nd), 3(rd), and 4(th) cervical vertebrae (P > 0.05). Base length, upper border length, body length, posterior height, anterior height, and body height of the 3(rd) and 4(th) cervical vertebrae were also similar between groups (P > 0.05). CONCLUSIONS: The results of this study supports that sagittal craniofacial pattern has no effect on the accuracy of using the methods assessing CVM and calculating cervical vertebral age.

Patients' and parents' concerns and decisions about orthodontic treatment.

OBJECTIVE: Patients' and parents' expectations are important in orthodontic treatment decision making. The literature generally demonstrates the perceived benefits of orthodontic treatment, but patients' and their parents' concerns about orthodontic treatment have not been investigated comprehensively. The aim of this study was to identify patients' and parents' concerns about orthodontic treatment and compare them according to sex, age, and treatment demand level. METHODS: One hundred and eighty-nine children and their parents were interviewed about concerns related to orthodontic treatment. Patients and parents were asked about orthodontic treatment decisions. Answers were recorded as "yes," "no," or "don't know." Chi-squared and Fisher's exact tests were used to compare concerns between age groups, sexes, and treatment demand levels. Kappa statistics were used to assess agreement between patients and their parents. RESULTS: Concerns about orthodontic treatment were gathered under 10 items as follows: "feeling pain," "the appearance of braces," "being teased," "avoiding smiling," "speech problems," "dietary changes," "problems with transportation," "economic problems," "long treatment duration," and "missing school." There was no statistically significant difference in concerns between the sexes or age groups. Some concern items and treatment demand were inversely related in patients. CONCLUSIONS: The results of this study demonstrate patients' and parents' concerns about orthodontic treatment. Differences between the concerns of patients with different treatment demands imply that children might reject orthodontic treatment because of their concerns. Appropriate consultation of patients addressing their concerns may help reduce anxiety and improve the acceptance of treatment.