Impact of effervescent denture cleaning tablets on color and surface characteristics of additively manufactured and hand-cast splint materials.

OBJECTIVES: This study is to evaluate the color stability, surface roughness, and hardness of additively manufactured and hand-cast splint materials after a 6-month commercially available denture cleaning tablet immersion simulation. MATERIALS AND METHODS: Disc-shaped additively manufactured and hand-cast auto polymerizing acrylic resin specimens were prepared (N = 40 each). All specimens were exposed to coffee solution totally 2 days. Thereafter, all specimens were immersed into three different effervescent solutions that simulated 6 months of clinical use. The total color change (ΔE*ab), surface roughness (Ra), and Vickers hardness (Vh) were measured at baseline and after immersion protocols. A two-way ANOVA and Bonferroni's post hoc test were used for color change. The dependent t-test and ANOVA were used for roughness and hardness evaluation. RESULTS: Additively manufactured splint materials were more affected by coffee immersion. It was observed that all denture cleaning tablets induced a noticeable alteration in color of the specimens (p < 0.05). Roughness and hardness measurement changes after solution immersions were statistically significant for both splint groups (p < 0.05). On the other hand, distilled water and denture cleaning tablets created similar roughness and hardness measurements at baseline and after immersion. CONCLUSIONS: After 6 months use of tested cleaning tables, the color stability, surface roughness, and hardness of both groups were affected. The evaluation of the surface properties of splint materials could be recommended to the dentists in periodic controls during splint treatments. CLINICAL RELEVANCE: The use effervescent denture cleaning tablets altered the surface characteristics of tested splint materials over time with nonsignificant difference between each other. After 6 months, awareness should be raised about surface characteristics of splint materials.

Is wear time of Hawley retainers measured with microsensors related to mandibular arch stability?

PURPOSE: The aim of this study was to show a possible correlation between the mean wear time of Hawley retainers and long-term mandibular arch stability as assessed via wear time analysis with microsensors. METHODS: This longitudinal retrospective study comprised 47 subjects (mean age 16.30 ± 1.06 years) having been treated with a nonextraction protocol and presenting moderate crowding at pretreatment. For retention, all patients were instructed to use a mandibular Hawley retainer for 12 months, and wear time was documented every 3 months during a posttreatment period of 6 months using TheraMon software. These individuals were divided into two groups. Those who adhered to a wear time equal to or more than 12 h/day (group 1A; N = 17) and those who complied for less than 12 h/day (group 2A; N = 30) were compared with respect to changes of the mandibular arch during the first 6 months of retention. Furthermore, a subgroup of 28 patients who completed a 12-month follow-up period were again divided into two groups: the individuals in group 1B (N = 12) adhered to a wear time equal to or more than 8 h/day, while those in group 2B (N = 16) complied for less than 8 h/day. Little's Irregularity Index, intercanine and intermolar widths, arch length, overjet, and overbite were measured on mandibular models taken at pretreatment (T0) and posttreatment (T1), as well as 6 months (T2) and 12 months (T3) after debonding. Pearson correlation test, independent samples t­test, and Mann-Whitney U test were used for statistical evaluation. RESULTS: From T1 to T2, group 1A and group 2A showed a significant relapse in intermolar width with a difference in the median value of 0.38 mm (p = 0.019). At the complete 12-month follow-up, the increase in Little's irregularity score was significantly greater in group 2B (2.54 ± 1.29 mm) than in group 1B (1.32 ± 1.03 mm; p = 0.012). The established wear time measurements showed significant negative correlations with the Little's irregularity score and overjet changes between T1 and T3 (p < 0.05). CONCLUSIONS: The results emphasized that the use of a retainer should not fall below a level of at least 8 h/day.

Does different vertical position of maxillary central incisors in women with different facial vertical height affect smile esthetics perception?

BACKGROUND: The aim of this study was to assess the esthetic perceptions of orthodontists, prosthodontists and laypersons with regard to different vertical positions of the maxillary central incisors related to lateral incisors for different facial vertical height cases. SUBJECT AND METHODS: Frontal full-face photographs showing social smiles of three adult women aged between 18 and 25 years were used. Vertical position of the maxillary central incisor was changed (intruded or extruded) with 0.5 mm increments according to the reference gingival line resulting five images for each woman in a full-face view yielding a total of 15 images. A visual analog scale was placed below each smile to allow the raters to evaluate the attractiveness of each smile independently. One-way analysis of variance was used to determine whether there was a difference between more than two independent groups in terms of quantitative variables. Comparisons of more than two dependent groups were examined with repeated measures one-way ANOVA. The significance level was taken as 0.05 for all analyses. RESULTS: For increased facial vertical height, the highest scores for orthodontists were given to the 0.5 mm extruded (64.18 ± 26.36), for prosthodontists to the control (57.28 ± 19.80), and for layperson to the 1 mm extruded (61.27 ± 25.98) central incisor position. For decreased facial vertical height, the highest scores were obtained at the 0.5 mm intrusion with an increasing pattern from orthodontists to laypersons (63.95 ± 22.08 for orthodontists, 79.87 ± 21.43 for prosthodontists, and 79.88 ± 19.17 for laypersons). All three rater groups gave the highest scores to the 0 mm (control) smile design for normal facial vertical height. When these scores were compared among the groups, laypersons gave significantly higher scores compared to orthodontists (p < 0.001) and prosthodontists (p = 0.005). CONCLUSIONS: The facial vertical height significantly affected the perception of smile esthetics. Keeping the distance between the central and lateral incisors longer than 1 mm in individuals with increased facial height may be important in terms of increasing patient satisfaction in terms of clinical aesthetics. On the contrary, keeping the distance between the central and lateral incisors shorter than 1 mm may create a more esthetically acceptable result in individuals with short facial height.

No-primer adhesive vs. self-adhesive resin: bonding strength following LED curing.

PURPOSE: The goal of this study was to compare the shear bond strength (SBS) and failure modes of three different adhesive resins following the use of two different dental curing light units. METHODS: A total of 160 human premolars were randomly divided into four groups (N = 40 for each): group 1, Transbond™ XT (3M Unitek, Monrovia, CA, USA) adhesive paste; group 2, Heliosit Orthodontic paste with no primer; group 3, Maxcem Elite (Kerr, Orange, CA, USA) self-adhesive resin with prior etching; group 4, Maxcem Elite self-adhesive resin with no etching. Each group was further divided into 2 subgroups: half (named "a") were cured with VALO LED (Ultradent Products, South Jordan, UT, USA), and the other half (named "b") with the Elipar LED unit (3M Unitek LED, Monrovia, CA, USA). The brackets were submitted to SBS testing 24 h after bonding. Adhesive Remnant Index (ARI) scores and bonding time were also measured. Two-way analysis of variance (ANOVA) and Kruskal-Wallis tests were used for statistical analysis. RESULTS: No significant differences in SBS were observed when comparing the two different LED devices within the same bonding material. The mean SBS of group 1 was significantly higher compared to groups 2, 3, and 4 (p < 0.001). Mean SBS values of groups 2 and 3 were significantly higher than that of group 4 (p < 0.001). ARI scores were significantly different in groups 4a and 4b compared to the other groups (p < 0.05). Group 4a showed significantly lower bonding time/tooth compared to the other groups except to groups 3a and 4b (p < 0.001). CONCLUSIONS: Decreasing curing time using high-power LED device did not significantly affect SBS. However, the composite type did affect SBS.

Symmetry of crown widths in subjects with unilateral maxillary lateral incisor agenesis.

PURPOSE: The aim of this study was to compare mesiodistal width and symmetry of maxillary and mandibular teeth in subjects with and without unilateral maxillary lateral incisor agenesis. PATIENTS AND METHODS: The study group consisted of 31 patients with unilateral maxillary lateral incisor agenesis (19 females, 12 males, mean age: 16.55 ± 5.24 years), and a control group of 31 patients (19 females, 12 males, mean age: 16.58 ± 4.41 years) without agenesis. Mesiodistal dimensions of all teeth except second molars were measured. Paired samples t­test and Wilcoxon signed-rank test were used for intragroup comparisons. Independent samples t­test was used for intergroup comparisons. RESULTS: In the study group, mesiodistal dimensions of maxillary canine, second premolar, first molar, mandibular second premolar and first molar teeth on the agenesis side were significantly smaller than on the contralateral side (p < 0.05). In the control group, no significant difference was seen in mesiodistal dimensions between right and left sides. In the study group, mesiodistal dimensions of all teeth on the lateral agenesis side were significantly smaller than on the control side (p < 0.05). On the side without lateral agenesis, all teeth except the maxillary and mandibular first molars and mandibular second premolar teeth were significantly smaller than on the control side (p < 0.05). Total mesiodistal dimensions of the maxillary teeth were significantly smaller on the lateral agenesis side than on the contralateral side (p = 0.001). Total tooth size of the study group was significantly smaller than for the control group (p < 0.05). CONCLUSION: Patients with unilateral maxillary lateral incisor agenesis might have asymmetries in tooth width and have smaller teeth than individuals without agenesis.

A comparison of self-esteem and social appearance anxiety levels of individuals with different types of malocclusions.

OBJECTIVE: The aim was to compare Rosenberg self-esteem scale (RSES), sensitivity to criticism scale (STCS) and social appearance anxiety scale (SAAS) scores of individuals with different types of malocclusions, and investigate the correlation between these scores and the index of complexity, outcome and need (ICON) score. MATERIALS AND METHODS: One hundred and twenty individuals, who did not have any previous orthodontic treatment, were included. Group 1 included 40 patients with Class I malocclusion (median age of 14 years), Group 2 included 40 patients with Class II malocclusion (median age of 14.25 years) and Group 3 included 40 patients with Class III malocclusion (median age of 15.15 years). ICON scores were 46, 53 and 56 for Groups 1, 2 and 3, respectively. RSES, STCS and SAAS questionnaires were performed to the patients. Student's t-test, one-way analysis of variance (ANOVA), Mann-Whitney's U and Kruskal-Wallis's tests were used for the statistical analysis. RESULTS: Group 1 showed significantly higher level of RSES scores compared to Groups 2 and 3 (p<.05). STCS scores were found to be significantly higher in Group 2, compared to other groups (p<.05). Group 1 (32.53 ± 8.94) showed significantly lower level of SAAS scores compared to Group 2 (39.63 ± 9.28) and Group 3 (39.42 ± 10.54) (p<.05). A significant positive correlation was found between the ICON and SAAS scores (r = 0.247, p=.007). CONCLUSIONS: Adolescents with Class II and III malocclusions reported higher levels of social appearance anxiety scores, and lower levels of self-esteem scores compared to Class I. Complexity of orthodontic treatment need showed a significant impact on social appearance anxiety.

Vertical Facial Skeletal Asymmetry and Occlusal Cant Relationship in Patients With Unilateral Cleft Lip and Palate.

OBJECTIVE: To evaluate the maxillary and mandibular vertical skeletal asymmetries, and the correlation between these asymmetries and occlusal cant in patients with unilateral cleft lip-palate (UCLP). METHODS: Anteroposterior radiographs of 25 patients with UCLP (UCLP group, mean age: 20.98 ± 4.88 years) and 25 subjects without cleft (control group, mean age: 19 ± 2.86 years) were included. Independent samples t test, Mann-Whitney U test and Pearson correlation analysis were performed based on linear and angular measurements. RESULTS: Lower facial horizontal asymmetry did not show statistically significant difference between the UCLP and control groups. However, vertical asymmetry of (a) the lateral cranial base (P = .014), (b) the nasomaxillary region (P < .001), (c) the maxillary dentoalveolus (P = .001), and (d) the lower face (P = .038) were all found to be significantly greater in UCLP group. The occlusal cant angle was also significantly greater in patients with UCLP compared to the controls (P = .016). While the occlusal cant angle was found to be correlated with the vertical asymmetry of the occlusal cant (r = 0.931, P < .001), maxillary cant angle was found to be correlated with the vertical asymmetry of the maxillary dentoalveolus (r = 0.655, P < .001). CONCLUSIONS: There was no correlation between the occlusal cant and the vertical and horizontal skeletal asymmetries. Vertical asymmetries of the lower face and the medial cranial base were negatively correlated with the horizontal lower facial asymmetry.

Comparison of Transverse Craniofacial Dimensions Between Growing Individuals With Unilateral Cleft Lip and Palate and Age-and Sex-Matched Noncleft Controls.

OBJECTIVE: The study aimed to assess the transverse craniofacial dimensions of patients (age, 7-14 years) with unilateral cleft lip and palate (UCLP), compare these dimensions with those of noncleft individuals, and identify the correlations between the nasal and maxillary transverse widths of patients with UCLP. DESIGN: A cross-sectional study. PARTICIPANTS: Eighty patients operated on for complete UCLP (UCLP group; 35 girls, 45 boys; median age: 10.7 [7.9-14] years) and 80 age- and sex-matched noncleft individuals (control group; 35 girls, 45 boys; median age: 10.7 [7.3-14] years). INTERVENTIONS: Interorbital, bizygomatic, nasal, maxillary skeletal, maxillary molar, mandibular molar, and antegonial width measurements were performed using posteroanterior cephalometric radiographs. Intergroup comparisons were conducted by using the independent samples t-test and Mann-Whitney U test. Correlation between the variables was examined using Pearson correlation analysis. RESULTS: The bizygomatic, maxillary skeletal and molar, mandibular molar, and antegonial widths in the UCLP group were significantly less than those in the control group (P < .05). A positive correlation was found between the maxillary skeletal and nasal widths (r = 0.550, P < .001) and between the maxillary molar and nasal widths (r = 0.560, P < .001). CONCLUSIONS: In individuals with UCLP, the bizygomatic, maxillary skeletal and molar, mandibular molar, and antegonial widths were significantly less than those in noncleft individuals. As the maxillary skeletal and dental widths presented a positive correlation with the nasal width, a decrease in nasal width must be considered when maxillary constriction is noted.

The Effect of Live-Video Demonstration on Dental Students' Orthodontic Bending Performance.

The aims of this study were to evaluate the effects of a live-video teaching tool on the performance of dental students in bending an orthodontic vestibular arch and to assess the students' perceptions of the technology. All 135 fourth-year dental students in the 2018 academic year at Hacettepe Dental School, Ankara, Turkey, were invited to participate in the study; after exclusions, the remaining 116 were randomly divided into two demonstration cohorts. These students had no prior experience bending an orthodontic wire. Cohort 1 (control, N=58) was shown a conventional live demonstration of the orthodontic bending of a vestibular arch, and Cohort 2 (experimental, N=58) was shown a live-video demonstration of the same procedure. Both cohorts saw the demonstration before beginning the exercise and were evaluated afterwards on their performance of the procedure. In addition, the students' perceptions of the demonstration techniques were collected with a questionnaire. The results did not show any significant differences in the students' bending scores between the control and experimental cohorts (p=0.767). The median values on the questionnaire indicated almost no statistically significant difference in responses between the cohorts. The only significant difference was that Cohort 1 had a higher percentage who answered "yes" they would like to rewatch the demonstration than did Cohort 2 (p=0.024). In this study, the live-video technique was found to be as effective as a conventional live demonstration for orthodontic practical education, suggesting that either technique could be used as an appropriate method for training in orthodontic wire bending.

Comparison of Live-Video and Video Demonstration Methods in Clinical Orthodontics Education.

The aim of this study was to compare the effectiveness of live-video and video demonstration methods in training dental students in orthodontic emergency applications. A total of 105 fifth-year dental students at a dental school in Turkey participated in the study in 2018. A pretest was given to the students to evaluate their level of knowledge about band cementing and re-bonding of brackets. Subsequently, two clinical applications were demonstrated with either live-video or video demonstration. During the live-video demonstration, the lecturer gave information about the steps of the procedure while performing the clinical application on the patient using a camera attached to the loupes. The students were able to see the process on the screens. During the video demonstration, previously recorded videos of those clinical applications were shown, and information was given to students in a classroom. On the next day, posttests were given to the students. The posttest also asked students to give their opinions about both methods. The results showed that the mean posttest scores on the video demonstration were significantly higher than on the live-video demonstration. However, no significant difference between the demonstration methods was found with regard to increase of scores from pre- to posttest. Most students preferred use of the two demonstrations together for education in the clinical orthodontics lecture. This study found that the two demonstration methods had comparable effects on increasing students' level of knowledge. However, from the students' perspective, the two should be used together to achieve the highest effect.

A comparative assessment of clinical efficiency between premium heat-activated copper nickel-titanium and superelastic nickel-titanium archwires during initial orthodontic alignment in adolescents: a randomized clinical trial.

BACKGROUND: To compare the clinical efficiency of premium heat-activated copper nickel-titanium (Tanzo Cu-NiTi) and NT3 superelastic NiTi during initial orthodontic alignment. SUBJECT AND METHODS: A total of 50 patients were randomly allocated to 1 of 2 different archwire types (group 1, Tanzo Cu-NiTi; group 2, NT3 superelastic NiTi). Eligibility criteria included Class I or Class II malocclusion, moderate maxillary anterior crowding, and healthy periodontal condition. Impressions of the upper arches were taken before archwire placement (T0) and at every 4 weeks (T1, T2, T3, and T4). For T1 and T2 stages, 0.014-in., and for T3 and T4 stages, 0.018-in. archwires were used. The primary outcome was the alignment efficiency assessed using Little's irregularity index. The secondary outcomes were arch width and incisor inclination changes. Data were analyzed using independent samples t test, repeated measures ANOVA, and Mann-Whitney U test. Marginal models were established for the estimation of coefficients. RESULTS: The anterior irregularity index reduction was mostly observed between T0 and T2 periods, which were respectively - 7.40 ± 0.50 mm (p < 0.001; 95% CI, - 8.94, - 5.85) and - 6.80 ± 0.55 mm (p < 0.001; 95% CI, - 8.49, - 5.12) for groups 1 and 2 (p < 0.001). With both wires, Little's irregularity index decreased over time, and the difference between the groups was not significant (p = 0.581; estimated effect size, 0.011). No statistically significant difference was found between the groups in terms of intercanine and intermolar width and incisor inclination changes. CONCLUSION: There were no significant between-group differences in alignment efficiency, arch width, and incisor inclination change. There was an increased alignment with 0.014-in. compared with 0.018-in. diameter archwire.

Reliability of cone-beam computed tomography for temporomandibular joint analysis.

OBJECTIVE: The aim was to assess the intraobserver and interobserver reliabilities of temporomandibular joint linear measurements and condylar shape classifications performed with cone-beam computed tomography (CBCT). METHODS: CBCT images of 30 patients were measured at two different time points by two orthodontists using the Dolphin 3D program (n = 60). Anterior, posterior, and superior joint space measurements and sagittal joint morphology classification in the sagittal view and medial and lateral joint space and mediolateral width measurements and coronal joint morphology classification in the coronal view were recorded. Intraclass-interclass correlation coefficients (ICC) and kappa statistics were used to assess intraobserver and interobserver reliability for the measurements and morphology classifications, respectively. RESULTS: The ICC values were good for measurements of the posterior joint space by observer I and for measurements of the posterior, medial, and lateral joint spaces by observer II, while the other intraobserver measurements were excellent. Only the mediolateral width measurements showed excellent interobserver ICC values, while the other measurements showed good interobserver ICC values. Intraobserver agreement for the sagittal morphology classifications was moderate (κ = 0.479) and almost perfect (κ = 0.858) for observers I and II, respectively, while the corresponding agreement for the coronal morphology classifications was substantial for both observers. The interobserver agreement values for sagittal and coronal morphology classifications were slight (κ = 0.181) and fair (κ = 0.265), respectively. CONCLUSIONS: Linear temporomandibular joint measurements were reproducible and reliable in both intraobserver and interobserver evaluations. However, interobserver agreement for assessments of condylar shape was low.

Clinical performance of precoated brackets and self-etch bonding technique: a prospective comparative study.

OBJECTIVE: The aim was to compare the clinical performance of uncoated and adhesive precoated brackets bonded with either self-etching primer (SEP) or conventional two-step etch and primer method (CEM). SUBJECTS AND METHODS: The sample consisted of 63 patients with a mean age of 15.20 ± 1.6 years. In group I (n = 15), uncoated brackets and CEM; in group II (n = 16), precoated brackets and CEM; in group III (n = 16), uncoated brackets and SEP; in group IV (n = 16), precoated brackets and SEP were used for bonding. Bonding time, bracket failure rate, and adhesive remnant index (ARI) scores were measured. The mean orthodontic treatment time was 1.13 ± 0.18 years. One-way variance ANOVA was used to determine bonding time differences and the chi-square test was used to determine differences in bracket failure rates and ARI scores. RESULTS: The bonding time was significantly lower for Groups III and IV, when compared to Groups I and II (p < 0.001). The bond failure rates were not different between the groups. Significant difference was observed between the procedures in relation to ARI scores (p < 0.001), which were higher in group IV. CONCLUSIONS: Precoated brackets with SEP application significantly reduced chair time without compromising bracket failure rate. CLINICAL RELEVANCE: Precoated brackets with SEP application can be safely used for bonding. Regarding the mode of failure, this group can be thought as favorable with a reduced risk of enamel tear.

Evaluation of changes in the maxillary alveolar bone after incisor intrusion.

OBJECTIVE: This study was performed to investigate the changes in alveolar bone after maxillary incisor intrusion and to determine the related factors in deep-bite patients. METHODS: Fifty maxillary central incisors of 25 patients were evaluated retrospectively. The maxillary incisors in Group I (12 patients; mean age, 16.51 ± 1.32 years) were intruded with a base-arch, while those in Group II (13 patients; mean age, 17.47 ± 2.71 years) were intruded with miniscrews. Changes in the alveolar envelope were assessed using pre-intrusion and post-intrusion cone-beam computed tomography images. Labial, palatal, and total bone thicknesses were evaluated at the crestal (3 mm), midroot (6 mm), and apical (9 mm) levels. Buccal and palatal alveolar crestal height, buccal bone height, and the prevalence of dehiscence were evaluated. Two-way repeated measure ANOVA was used to determine the significance of the changes. Pearson's correlation coefficient analysis was performed to assess the relationship between dental and alveolar bone measurement changes. RESULTS: Upper incisor inclination and intrusion changes were significantly greater in Group II than in Group I. With treatment, the alveolar bone thickness at the labial bone thickness (LBT, 3 and 6 mm) decreased significantly in Group II (p < 0.001) as compared to Group I. The LBT change at 3 mm was strongly and positively correlated with the amount of upper incisor intrusion (r = 0.539; p = 0.005). CONCLUSIONS: Change in the labial inclination and the amount of intrusion should be considered during upper incisor intrusion, as these factors increase the risk of alveolar bone loss.

Tooth color change due to different etching and debonding procedures.

OBJECTIVES:: To compare the effects of different etching techniques, 12-, 24-bladed tungsten carbide burs, and polishing discs on tooth color changes during orthodontic treatment. MATERIALS AND METHODS:: 59 individuals (mean age: 15.20 ± 1.59 years) were divided into four groups: 37% phosphoric acid and adhesive primer was used in Groups I and II whereas self-etch primer was used in Groups III and IV for enamel preparation. After orthodontic treatment, residual adhesives were cleaned with 12-bladed tungsten carbide burs in Groups I and III, while 24-bladed tungsten carbide burs were used in Groups II and IV. All teeth were polished with medium and fine Sof-Lex XT discs (3M ESPE, St Paul, Minnesota). Color measurements were taken from upper incisors and canines at pretreatment (T0), after cleaning with tungsten carbide burs (T1) and polishing with discs (T2). Wilcoxon test was used for evaluation of L*, a*, b* changes and Kruskal-Wallis for intergroup comparison of color changes. RESULTS:: L*, a*, b* values, except a* at Groups I, II, IV, and b* at Group III, changed significantly ( P < .05). Groups III and IV showed significantly different color alterations from T0 to T1 ( P < .05). After polishing, tooth color alterations were not significantly different among the groups. CONCLUSIONS:: In self-etch bonding groups, a 12-bladed tungsten carbide bur caused less color change than the 24-bladed tungsten carbide bur. Orthodontic treatment resulted with visible and clinically unacceptable tooth color alterations regardless of the enamel preparation and clean-up techniques. Polishing reduced the effect of tungsten carbide burs, but did not affect the total influence of orthodontic treatment on the tooth color.

Stability comparison of two different dentoalveolar expansion treatment protocols.

OBJECTIVE: The aim of this study was to compare the longitudinal stability of the conventional straight-wire system after the use of a quad-helix appliance with Damon self-ligating system in patients with Class I malocclusion. METHODS: 27 adolescent patients were evaluated at three different periods: pre-treatment (T1), post-treatment (T2) and three years post-treatment (T3). Group 1 included 12 patients (with a mean age of 14.65 year) treated with Damon 3MX bracket system; and Group 2 included 15 patients (with a mean age of 14.8 year) who underwent orthodontic treatment with Roth prescribed brackets after expansion with Quad-Helix appliance. Relapse was evaluated with dental cast examination and cephalometric radiograph tracings. Statistical analysis was performed with IBM-SPSS for Windows software, version 21 (SPSS Inc., Chicago, IL). A p-value smaller than 0.05 was considered statistically significant. RESULTS: There were significant increases in all transverse dental and postero-anterior measurements (except for UL6-ML mm in Group 1) with active treatment. There was some significant relapse in the long-term in inter-canine width in both groups and in the inter-first premolar width in Group 2 (p< 0.05). Significant decrease in all frontal measurements from T2 to T3 was seen for both groups. Upper and lower incisors significantly proclined in T1-T2 (p< 0.05), however no relapse was found for both groups. When two systems were compared, there was no significant difference for the long-term follow-up period. CONCLUSION: Conventional (quad-helix appliance with conventional brackets) and Damon systems were found similar with regard to the long-term incisor positions and transverse dimension changes of maxillary arch.

Effects of Three Different Orthodontic Treatment Methods on the Stability of Mandibular Incisor Alignment.

OBJECTIVE: To compare the effects of extraction, non-extraction and air-rotor stripping treatments on mandibular dental arch dimensions, lower incisor positions and evaluate their effects on the stability of the treatment. STUDY DESIGN: The sample consisted of 44 patients with Class I malocclusion and moderate crowding including 15 patients treated with extraction, 13 with air-rotor stripping (ARS), and 16 with non-extraction treatment. The records were taken at pretreatment (T0), end of active orthodontic treatment (T1), minimum 3 years post-treatment (T2). The model and cephalometric measurements were evaluated. For statistical analyses ANOVA and Welch test was applied. RESULTS: At post-retention period Little's irregularity indices were increased to 1.96 mm, 2.38 mm and 3.59 mm for extraction, ARS and non-extraction groups respectively (p<0.05). At T1-T2, intercanine widths were decreased significantly at all groups (p<0.05). The arch length and arch depth decreased significantly at extraction group (p<0.05) from T0 to T1 and remained the same at T2 (p>0.05). The lower incisors were retroclined with treatment and slightly proclined at post-retention period in extraction group. In ARS and non-extraction group, lower incisors proclined with treatment and remained the same at post-retention. CONCLUSION: At all groups the irregularity indices relapsed but did not return to pretreatment values. Although significant increase at intercanine width was only observed in non-extraction treatment, at post-retention phase, intercanine widths were significantly decreased at all groups. The changes at lower incisor inclinations relapsed slightly in extraction group but remained the same in the other groups.

Stability comparison of two different dentoalveolar expansion treatment protocols

ABSTRACT Objective: The aim of this study was to compare the longitudinal stability of the conventional straight-wire system after the use of a quad-helix appliance with Damon self-ligating system in patients with Class I malocclusion. Methods: 27 adolescent patients were evaluated at three different periods: pre-treatment (T1), post-treatment (T2) and three years post-treatment (T3). Group 1 included 12 patients (with a mean age of 14.65 year) treated with Damon 3MX bracket system; and Group 2 included 15 patients (with a mean age of 14.8 year) who underwent orthodontic treatment with Roth prescribed brackets after expansion with Quad-Helix appliance. Relapse was evaluated with dental cast examination and cephalometric radiograph tracings. Statistical analysis was performed with IBM-SPSS for Windows software, version 21 (SPSS Inc., Chicago, IL). A p-value smaller than 0.05 was considered statistically significant. Results: There were significant increases in all transverse dental and postero-anterior measurements (except for UL6-ML mm in Group 1) with active treatment. There was some significant relapse in the long-term in inter-canine width in both groups and in the inter-first premolar width in Group 2 (p< 0.05). Significant decrease in all frontal measurements from T2 to T3 was seen for both groups. Upper and lower incisors significantly proclined in T1-T2 (p<0.05), however no relapse was found for both groups. When two systems were compared, there was no significant difference for the long-term follow-up period. Conclusion: Conventional (quad-helix appliance with conventional brackets) and Damon systems were found similar with regard to the long-term incisor positions and transverse dimension changes of maxillary arch.

RESUMO Objetivo: comparar a estabilidade longitudinal após o tratamento de pacientes com má oclusão de Classe I usando o sistema Straight-wire convencional - depois da expansão com aparelho quadri-hélice - e o sistema autoligável Damon. Métodos: 27 pacientes adolescentes foram avaliados em três períodos distintos: pré-tratamento (T1), pós-tratamento imediato (T2) e três anos pós-tratamento (T3). O Grupo 1 incluiu 12 pacientes (com idade média de 14,65 anos) tratados com o sistema de braquetes Damon 3MX e o Grupo 2 incluiu 15 pacientes (com idade média de 14,8 anos), submetidos a tratamento ortodôntico com braquetes prescrição Roth após expansão com aparelho quadri-hélice. A recidiva foi avaliada por meio de exame dos modelos de estudo e traçados cefalométricos. A análise estatística foi realizada com o software IBM-SPSS para Windows, versão 21 (SPSS Inc., Chicago, IL). Valores de p< 0,05 foram considerados estatisticamente significativos. Resultados: após o tratamento ativo, ocorreu aumento significativo em todas as medidas transversais dentárias e posteroanteriores (exceto para a UL6-ML mm, no Grupo 1). Em longo prazo, ocorreu recidiva significativa (p< 0,05) na distância intercaninos em ambos os grupos, e na distância interprimeiros pré-molares no Grupo 2. De T2 para T3, observou-se diminuição significativa em todas as medidas frontais, para ambos os grupos. De T1 para T2, os incisivos superiores e inferiores sofreram vestibularização significativa (p< 0,05); porém, nenhuma recidiva ocorreu em qualquer um dos dois grupos. Ao se comparar os dois sistemas, não foi encontrada qualquer diferença significativa no período de acompanhamento em longo prazo. Conclusão: o sistema convencional (aparelho quadri-hélice e braquetes convencionais) e o sistema Damon apresentaram desempenho semelhante, em longo prazo, em termos das posições dos incisivos e das mudanças ocorridas na dimensão transversal da arcada superior.

Soft tissue effects of three different Class II/1-camouflage treatment strategies.

OBJECTIVE: Aim of this retrospective study was to compare soft tissue effects of Class II treatments with the forsus fatigue resistant device (FRD), the pendulum appliance, and the extraction of two maxillary premolars, all of which were combined with pre-adjusted fixed appliances. PATIENTS AND METHODS: The sample of 54 patients with Class II malocclusions was divided in three groups: group I patients (mean age = 15.91 years) were treated with the FRD concurrently used with fixed appliances; group II patients (mean age = 16.08 years) were treated with the pendulum appliance combined with a Nance and headgear followed by fixed appliances; and group III patients (mean age = 19.04 years) were treated with the extraction of two maxillary premolars with miniscrew anchorage. Soft tissue and dentoskeletal parameters were measured on pretreatment (T1) and posttreatment (T2) lateral cephalograms. The changes from T1 to T2 were compared between the groups using Kruskal-Wallis test, and treatment differences were evaluated with the Wilcoxon test at p < 0.05. RESULT: Soft tissue measurement changes related to the upper and lower lips were significantly greater in group II than in group III (p < 0.05). Upper incisor measurement changes were significantly different between groups II and III. Lower incisor measurement changes were significantly different between groups I and III and groups II and III (p < 0.05). CONCLUSIONS: Pendulum and extraction treatment groups showed significant differences in relation with the upper and lower lip positional changes, which were significantly greater in the pendulum group. Treatment time with the extraction treatment was statistically shorter than with the nonextraction protocols.

Comparing the effects of Essix and Hawley retainers on the acoustics of speech.

OBJECTIVE: The aim of this study was to compare the effects of two retainer types (Essix and Hawley) on speech performance. SUBJECTS AND METHODS: The speech articulation of 30 patients was evaluated prospectively. Five patients did not appear during the follow-up periods. The patients were randomly divided into retention groups by treatment allocation cards as Essix and Hawley. The Essix group included 13 participants with a mean age of 15.3±2.4 years; the Hawley group included 12 participants with a mean age of 16.3±2.56 years. Speech sound assessments were performed on the first day and 1 week, 4 weeks, and 3 months later. On the first day, the assessments were conducted prior to inserting the retainers, immediately after maxillary and mandibular retainer application, individually, and with both retainers applied. The acoustic analyses were obtained using spectral and temporal parameters. RESULTS: Statistical analyses were performed with IBM SPSS for Windows, version 20. A P value less than 0.05 was considered statistically significant. The most apparent changes were found in the [a] vowel in the Hawley group, the [e] vowel in the Essix group, and the [u] vowel in both groups (P < 0.05). While the number of affected consonant-vowel couples in the Essix group was low, alterations were common in the Hawley group. There was a statistically significant difference (P < 0.05) in voice onset time of the [d] sound between the groups. LIMITATIONS: The trial had a small sample size and a short follow-up period. CONCLUSIONS: The Hawley retainer affected articulatory movements in consonant-vowel combinations more prominently than the Essix retainer did. Voice onset time of the consonant [d] in the Hawley group was shorter than normal, indicating rapid articulatory movement in the alveolar region.