Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie最新文献

Purpose: To explore the impact of oral hygiene practices, as well as beliefs and attitudes toward orthodontic treatment on white spot lesion (WSL) development and plaque accumulation in orthodontic patients.

Materials and methods: A total of 106 individuals (61 female, 45 male) patients aged 10-49 years who were treated with fixed appliances treatment completed a 14-question survey regarding aspects of their oral hygiene (OH) and orthodontic visits. The number of teeth with WSL and the plaque indexes were recorded for each patient. Poisson regression and linear regression models were used to analyze the association of survey responses with the observed WSLs and plaque accumulation, respectively.

Results: Participants of both sexes reported similar beliefs about OH (66% agreed to the importance of OH statements), practiced proper OH (69% good practices), and reported a similar perception regarding the quality of their OH routine and of their orthodontic treatment. However, in total, none of the findings was significantly related to the development of WSLs or plaque accumulation. Significantly fewer WSLs were observed in male patients who perceived themselves as having good control over OH. Female participants reported significantly higher expectations regarding posttreatment smile improvement compared to males. Overall, responses by male participants were deemed to be more accurate than those by female participants when related to WSL development and plaque accumulation.

Conclusion: Our survey hints at a possible relationship between WSL formation and patients' sense of control over OH routine in males. Future studies should further explore the effect of sex on the attitude toward and perception of OH in orthodontic patients. This survey highlights the multifactorial nature of WSL development in orthodontic patients and the complexity of predicting patient compliance.

Purpose: This study evaluated adhesive and cohesive failures and the surface wear of attachments employed in clear aligner treatment (CAT) using three-dimensional (3D) superimposition.

Methods: In all, 3D models of 150 teeth were obtained from intraoral scans from patients undergoing CAT with at least 4 months between each scan. Of the initial sample, 25 teeth were discarded, and 125 teeth were included in the study. Superimpositions of each individual tooth at the first and second time points were made using computer-aided design (CAD) software (Meshmixer; Autodesk, Mill Valley, CA, USA). Analyses were performed to compare surface wear and failures related to type of attachment (optimized/conventional), dental group (molars/premolars/anterior teeth), and arch (mandibular/maxillary). Mann-Whitney and Kruskal-Wallis statistical tests were applied with significance set at 5%.

Results: More surface wear was observed in conventional attachments, mandibular and anterior teeth with statistical significance for surface wear on the distal surface of conventional attachments (p < 0.05). Cohesive failure was observed in 10% of attachments, occurring most frequently on optimized attachments and molar teeth. Adhesive failure was observed in 10% of the samples, more frequently on conventional attachments and posterior teeth.

Conclusion: Attachment type (conventional vs. optimized) was significantly correlated with surface wear on the distal surface of the attachment. Arch (mandibular or maxillary) and group of teeth (anterior or posterior) showed no correlation with surface wear. Failure, both adhesive and cohesive, correlated with attachment type and group of teeth, but not with the arch in which they were located.

Background: The aim for this research was to evaluate and compare the impact, bond strength, and residual adhesive on the enamel surface after debonding of different orthodontic molar tubes. The tested materials were metal, composite, and newly introduced ceramic orthodontic molar tubes.

Materials and methods: In all, 66 first molar teeth were randomly divided into three groups. Metal, glass-fiber composite and ceramic orthodontic molar tubes were bonded and shear bond strength (SBS) tests were performed. The adhesive remnant index (ARI) scores after debonding were recorded and the enamel surfaces were investigated using scanning electron microscopy (SEM) after the adhesives were cleaned.

Results: The mean SBS values of the metal and ceramic tube groups were significantly higher than that of the glass-fiber composite tube group. The highest SBS values were recorded for the ceramic tube group (11.09 ± 2.51 MPa). Failure typically occurred at the adhesive-enamel interface in the ceramic group, whereas the majority of the samples in the glass-fiber composite group showed failure at the adhesive-tube base interface according to ARI and SEM investigations. ARI 1 and ARI 2 scores were commonly observed for the metal tube group.

Conclusions: All the molar tubes tested had generated clinically acceptable SBS values; however, the values for glass-fiber composite molar tubes were significantly lower than those for the ceramic and metal molar tubes. If the debonding procedure is performed carefully, the ceramic molar tubes may be an enamel-safe product for patients seeking fully esthetic orthodontic treatment.

Objectives: To evaluate and compare pharyngeal airway and tongue space changes after treatment with fixed functional appliances-Herbst and AdvanSync™ (Ormco, Orange, CA, USA) appliances-in skeletal class II patients in pre- and posttreatment lateral cephalograms.

Methods: For this randomized, controlled trial, 40 patients (21 male, 19 female) were divided into two groups-a Herbst group (mean age 12.6 ± 0.67 years) and an AdvanSync group (mean age 12.8 ± 0.66 years). Pre- and posttreatment (appliance therapy duration-8 months) lateral cephalograms were traced using a software program to evaluate pharyngeal airway and tongue space changes.

Results: Nasopharyngeal airway, velopharyngeal airway, glossopharyngeal airway, and hypopharyngeal airway increased in the Herbst group by 2.12 mm (p ≤ 0.001), 2.33 mm (p ≤ 0.001), 2.40 mm (p ≤ 0.01), and 1.57 mm (p ≤ 0.05), while in the AdvanSync group the increases were 1.89 mm (p ≤ 0.001), 1.21 mm (p ≤ 0.001), 1.18 mm (p ≤ 0.001), and 1.53 mm (p ≤ 0.001), respectively. In the Herbst group, tongue length and height increases were 2.04 mm (p ≤ 0.01) and 3.74 mm (p ≤ 0.001), while the values in the AdvanSync group were 2.41 mm (p ≤ 0.05) and 2.69 mm (p ≤ 0.001). The change of the tongue tip from the lower occlusal plane was 0.69 mm (p ≤ 0.001) in the Herbst group and 0.77 mm (p ≤ 0.001) in the AdvanSync group. The velopharyngeal airway dimension was correlated positively with that of the retroglossal oropharyngeal airway, which in-turn positively correlated with the laryngopharyngeal airway which correlated well with the distance of the tongue tip from the lower occlusal plane.

Conclusions: The airway dimensions and tongue parameters increased significantly in both treatment groups in the present study. These changes were higher in the Herbst appliance than in the AdvanSync group, except for the distance of the tongue tip from the lower occlusal plane. A significant difference between the pharyngeal airways was found only for the retropalatal oropharyngeal airway.

Purpose: Correction of a gummy smile by orthodontic treatment alone has recently become feasible with the use of miniscrews. However, the optimal treatment mechanics remain unclear. Here we cephalometrically evaluated jaw and tooth displacement in cases where a gummy smile was improved using a level anchorage system (LAS).

Methods: Sixteen patients underwent orthodontic treatment using an LAS consisting of a modified transpalatal arch and midpalatal miniscrews. Cephalometric pretreatment and posttreatment measurements were compared using the paired t‑test to determine significant skeletal and dental changes. The Mann-Whitney U test was used for nonparametric data. Spearman's rank correlation coefficient was used to evaluate correlations between different variables and the vertical change in prosthion position which was used to indicate the amount of gingival exposure.

Results: The changes noted after treatment were intrusion of the maxillary first molars (P < 0.001) combined with only minor extrusion of the mandibular first molars. Suppressed extrusion of the mandibular first molars was significantly correlated with greater upward movement of the prosthion (r = 0.676, P < 0.01). Upward movement of the prosthion was also significantly correlated with intrusion of the maxillary and mandibular incisors, anterior upward movement of the maxillary occlusal plane, and an increase of the SNP angle.

Conclusions: Treatment involving the combined use of miniscrews and a modified transpalatal arch resulted in intrusion of the maxillary first molars and maxillary incisors and consequently elevated the maxillary occlusal plane. The results of this study suggest that intruding the maxillary occlusal plane and minimizing mandibular molar extrusion were effective to induce autorotation of the mandible and to improve a gummy smile.

Purpose: The purposes of this study were to compare and evaluate the surface texture of different restorative computer-aided design and computer-aided manufacturing (CAD/CAM) materials before bonding and after debonding of metal orthodontic brackets.

Materials and methods: A total of 60 rectangular ceramic test specimens (n = 20 in each group) were prepared using feldspathic ceramic blocks (FLD; served as control), hybrid ceramic blocks (HC), and lithium disilicate ceramic blocks (LDC). Surface roughness (Ra) analysis was conducted using a profilometer before bonding the metal brackets. After the debonding and polishing procedures, a second surface roughness analysis was conducted on each specimen. The shear bond strength (SBS) test was applied to each specimen using a universal test machine for debonding the metal brackets. The debonded specimens were examined under a stereomicroscope and scored using a 4-step adhesive remnant index (ARI). The Ra and SBS values and the ARI scores were saved, and the data were analyzed statistically at a significance level of 0.05. One specimen from each group was examined under atomic force microscopy to visualize surface roughness. Furthermore, one specimen from each group was additionally prepared for scanning electron microscopy analysis.

Results: Statistically significant differences in SBS measurements were observed between all three groups. The highest SBS values were obtained from the FLD group, the lowest from the LDC group. The HC group showed significantly (P = 0.001) lower Ra values than the LDC and FLD groups after debonding and polishing. No significant differences were observed in the ARI scores between the groups.

Conclusions: Hybrid ceramics could be a suitable alternative for fixed restorations in adult patients receiving subsequent treatments with fixed orthodontic appliances.

Introduction: The purpose of this study was to compare efficacy of a manual and an interactive power toothbrush in orthodontic patients by assessing periodontal indexes and bacterial content of saliva samples.

Methods: Forty patients (20 females, 20 males; age range 12-18 years) with fixed orthodontic appliances were included in the study. The patients were randomly divided into two groups in a 1:1 ratio using sealed envelopes: group 1: manual toothbrush (Oral‑B Ortho Brush, Procter&Gamble Company, Dublin, Ireland), group 2: interactive power toothbrush (Oral‑B Genius 8900, Procter&Gamble Company, Marktheidenfeld, Germany). All participants were given the same toothpaste (Colgate Triple Action, Colgate-Palmolive, New York, NY, USA). The brushing procedure for each patient was described in detail, both orally and visually, utilizing a video demonstration. Plaque and bleeding index scores were recorded for both the lower and upper arches at the beginning of the study (T0) and at weeks 6 (T1) and 12 (T2). In addition, the numbers of Streptococcus (S.) mutans, Lactobacillus (L.) casei, and Porphyromonas (P.) gingivalis bacteria were determined using a real-time polymerase chain reaction (PCR) analysis in saliva samples collected at T0, T1, and T2 times. Mann-Whitney U test and Student's t test were used to compare data between the groups, and one-way analysis of variance (ANOVA) and Friedman tests were used to compare data from different time intervals for each group.

Results: Plaque index values were greater in group 1 at T1 and T2, although there was no difference between the groups at T0. The gingival index scores of both groups were similar at T0, T1, and T2. While group 2 had a larger number of salivary S. mutans at T0 and T2, there was no significant difference between the groups at T1. At all three time points, there was no significant difference in salivary L. casei levels between the groups.

Conclusions: Although the interactive power toothbrush was more effective at removing plaque than the manual toothbrush, the results of the gingival index did not reflect the plaque scores. The number of certain salivary bacteria and brush type did not appear to have a clear relationship.

Purpose: Chronological age often differs from dental and skeletal age. With orthopantomograms and lateral cephalograms, dental and skeletal development can be determined according to the methods published by Demirjian et al. and Baccetti et al. However, gender and skeletal class as possible confounders were frequently not considered and available norm values are not up-to-date. This retrospective cross-sectional study thus aimed to evaluate effects of skeletal class and gender on dental and skeletal age of growing patients and to generate updated norm values for contemporary Central-European patients.

Methods: A total of 551 patients were included in the dental and 733 in the skeletal age assessment, respectively. Dental analysis was based on tooth mineralisation stages in orthopantomograms (Demirjian) and skeletal age was defined by cervical vertebrae maturation stages (CVMS) in lateral cephalograms (Baccetti). Skeletal class was determined by the individualised ANB angle of Panagiotidis/Witt. With nonlinear regression analysis a formula for determining dental age was established. Effects of gender and skeletal class were evaluated and updated norm values generated.

Results: Inter- and intrarater reliability tests revealed at least substantial measurement concordance for tooth mineralisation and CVMS. Demirjian stages and CVMS significantly depended on gender with girls developing earlier. Skeletal class significantly affected skeletal age only, but without clinical relevance. Updated norm values for dental age differed significantly from the original values of Demirjian and the values for skeletal age differed from those published by Baccetti.

Conclusion: Optimised norms, separated by gender, increase precision in determining individual dental and skeletal age during orthodontic treatment planning. Further studies analysing the effect of skeletal class on dental and skeletal development are needed.

Background: This study aimed to evaluate the prevalence of retained primary teeth (RPT) associated with delayed permanent tooth eruption and the factors associated with this condition in German children.

Methods: This is a cross-sectional retrospective study that evaluated panoramic radiographs from orthodontic patients. The diagnosis of RPT was established according to Nolla developmental stage. The primary tooth was considered retained when its successor permanent tooth was in Nolla stage 8, 9, or 10. Statistical analysis was performed with an α of 5% (p < 0.05).

Results: A total of 102 children (48 girls and 54 boys), and 574 primary teeth and their respective permanent successor teeth were evaluated. We classified 192 teeth as RPT. Sixty-one (59.8%) children presented one or more RPT. Gender was not significantly different between RPT and control teeth (p = 0.838; odds ratio 0.95, confidence interval 95% 0.44-2.16). In the majority of the RPT cases (68.7%), no clear cause to explain the prolonged retention was identified. The pathological problems most commonly observed with RPT were dental fillings (19.3%), followed by dental caries (4.6%), and ectopic tooth eruption (2.1%).

Conclusions: The incidence of RPT associated with delayed permanent tooth eruption in German children was high and the most common pathological condition associated with RPT was dental caries.