Vasiliki Koretsi - Academia.edu (original) (raw)
Papers by Vasiliki Koretsi
Orthodontics deals with the correction of skeletal anomalies of the face occurring in the form of... more Orthodontics deals with the correction of skeletal anomalies of the face occurring in the form of jaw discrepancies. There is an abundance of findings in the literature that the development and growth of the cranial base influence facial shape and jaw discrepancies. Cranial base develops by the mechanism of endochondral ossification taking place at its midline axis, where all the synchondroses are located. Chondrogenesis is the initial and indispensable part of endochondral bone formation. In the light of evidence underlying the need of reactive oxygen species in the regulation of chondrogenesis, this study aimed to investigate the ubiquitously present antioxidant enzyme Gpx1 and its contribution to redox regulation in chondrogenesis. Provided that the levels of oxidative stress were previously found to fluctuate according to the differentiation stage of chondrocytes, the gene expression of Gpx1 was measured with quantitative RT-PCR during chondrogenic differentiation. For this purp...
Journal of Clinical Medicine
The aim of this systematic review is to compare the effect on the upper airways of orthopedic tre... more The aim of this systematic review is to compare the effect on the upper airways of orthopedic treatment for skeletal Class III malocclusion with untreated controls. Nine databases were searched up to August 2020 for randomized or nonrandomized clinical trials comparing orthopedic Class III treatment (facemask or chin-cup) to untreated Class III patients. After duplicate study selection, data extraction, and risk of bias assessment (Risk Of Bias In Non-randomized Studies-of Interventions [ROBINS-I]), random-effects meta-analyses of Mean Differences (MDs)/Standardized Mean Differences (SMD) and 95% Confidence Intervals (CIs) were performed, followed by the Grading of Recommendations Assessment, Development and Evaluation assessment evidence-quality. A total of 10 papers (9 unique nonrandomized studies) with 466 patients (42.7% male; average age 9.1 years) were finally included. Limited evidence indicated that compared to normal growth, maxillary protraction with facemask was associate...
Progress in Orthodontics
Objectives Adults with fixed orthodontic appliances are increasing nowadays. Compared with adoles... more Objectives Adults with fixed orthodontic appliances are increasing nowadays. Compared with adolescents, adults present biological differences that might influence treatment duration. Therefore, the aim of the study was to compare duration of treatment with fixed appliances between adults and adolescents. Materials and methods Eight databases were searched up to September 2019 for randomized and non-randomized clinical studies comparing treatment duration with fixed appliances in adolescents and adult patients. After duplicate study selection, data extraction, and risk of bias assessment with the Cochrane ROBINS-I tool, random effects meta-analyses of mean differences (MD) and their 95% confidence intervals (CIs) were performed, followed by assessment of the quality of evidence with GRADE. Results A total of 11 unique studies (one prospective and 10 retrospective non-randomized) with 2969 adolescents and 1380 adult patients were finally included. Meta-analysis of 7 studies found no s...
The Angle Orthodontist
Objective: To investigate changes in dental arch configuration, relationship, and malocclusion di... more Objective: To investigate changes in dental arch configuration, relationship, and malocclusion directly after Class II malocclusion treatment with a Balters bionator modified by Ascher as well as 20 years after treatment. Materials and Methods: Orthodontic dental cast analysis of 18 patients with skeletal Class II treated with a bionator without any additional fixed therapy was performed with a digital caliper at three stages: before (T0), after (T1) and 20 years after (T2) treatment. Arch perimeter and depth, intermolar and intercanine distance, overjet, overbite, sagittal molar and canine relationship, mandibular incisor irregularity (Little's index), and malocclusion (PAR index) were assessed. Results: During treatment (T0–T1), upper arch perimeter significantly increased with a significant decrease in the upper and lower arch perimeter long-term (T1–T2), whereas corresponding arch depths changed only slightly in both periods. Transverse intermolar width increased significant...
Clinical Oral Investigations
ObjectiveTo investigate if orthodontic model analysis with a digital caliper can be interchangeab... more ObjectiveTo investigate if orthodontic model analysis with a digital caliper can be interchangeably performed between plaster and printed dental models.Materials and methodsForty-eight plaster models were digitized with orthoX®scan (DENTAURUM) and 48 counterparts were printed with Objet30 Dental Prime (Stratasys). One examiner performed five repeated orthodontic model analyses (41 outcomes) with a digital caliper in each plaster and the corresponding printed model and was externally validated by a second examiner. Inter- and intra-examiner reliability and error were evaluated with intraclass correlation coefficients (ICCs) and Dahlberg’s formula, intra-examiner agreement with Bland-Altman analyses and Lin’s correlation coefficients (CCCs), and changing bias with regression analyses.ResultsInter- and intra-examiner ICCs and Dahlberg’s error were ≥ 0.75 and ≤ 0.5 mm, respectively, for most outcomes in both plaster and printed models. Intra-examiner agreement (systematic bias) between plaster and printed models ranged from − 0.45 to 0.45 mm. Ranges of limits of agreement were wide for cumulative outcomes, such as crowding maxilla and mandible (2.69 mm and 3.07 mm around zero, respectively). Tooth widths were measured slightly larger in printed models. Lin’s CCCs were ≥ 0.87 for all the outcomes between plaster and printed models, while no changing bias was detected.ConclusionIf orthodontic model analyses are consistently performed, plaster casts and their corresponding printed models obtained with orthoX®scan and Objet30 Dental Prime can be interchangeably used for clinical purposes in orthodontics.Clinical relevanceOrthodontic model analysis is important in treatment planning and printed dental models need to be validated regarding this diagnostic procedure.
Deutsches Arzteblatt international, Jan 23, 2018
The effectiveness of intraoral appliances (IOA), maxillary expansion (ME), and maxillomandibular ... more The effectiveness of intraoral appliances (IOA), maxillary expansion (ME), and maxillomandibular advancement (MMA) in the treatment of children and adults with obstructive sleep apnea (OSA) has not yet been adequately assessed. An umbrella review was performed based on established guidelines for evidence-based medicine. Data synthesis was performed only from randomized controlled trials with Paule-Mandel random-effects meta-analyses / meta-regressions using mean differences (MDs) and 95% confidence intervals (CIs) and was followed by the qualitative evaluation of the meta-evidence. 29 systematic reviews were included, 7 of which provided quantitative data. IOA were effective in improving apnea hypopnea index (AHI) compared to both, placebo appliances (12 trials; 525 patients; MD = -11.70; 95% CI: [-15.38; -8.01]; p<0.001) and no treatment (1 trial; 24 patients; MD = -14.30; [-21.59; -7.01]; p<0.001). Only the former comparison was supported by robust meta-evidence. Effectivene...
Treatment effects of removable functional appliances in patients with Class II malocclusion: a sy... more Treatment effects of removable functional appliances in patients with Class II malocclusion: a systematic review and meta-analysis
![Research paper thumbnail of Koretsi V, Zymperdikas VF, Papageorgiou SN, Papadopoulos MA. Treatment effects of removable functional appliances in patients with Class II malocclusion: a systematic review and meta-analysis. Eur J Orthod 2014 [Epub ahead of print]](https://attachments.academia-assets.com/35574075/thumbnails/1.jpg)
](Summary Objective: To assess the treatment effects of removable functional appliances (RFAs) in t... more Summary
Objective: To assess the treatment effects of removable functional appliances (RFAs) in treated versus untreated patients with Class II malocclusion by means of lateral cephalometric radiographs.
Search methods: Unrestricted electronic search of 18 databases and manual searches up to October 2013.
Selection criteria: Prospective randomized and non-randomized controlled trials reporting on cephalometric angular measurements of Class II patients treated with RFAs and their matched controls.
Data collection and analysis: Skeletal, dental, and soft tissue changes were annualized and stratified to short- and long-term effects. Methodological limitations were evaluated with the Cochrane Risk of Bias tool and the Downs and Black checklist. Mean differences (MDs) with their 95% confidence intervals (CIs) were calculated from random-effects meta-analyses. Patient- or appliance-related subgroup analyses and sensitivity analyses were performed with mixed-effects models.
Results: Seventeen studies were included (1031 patients; mean age: 10.6 years), with most of them originating from university clinics and reporting short-term effects (directly after the removal of RFAs). Treatment was associated with minimal reduction of SNA angle (11 studies, MD = −0.28 degree/year, 95% CI: −0.44 to −0.12 degree/year), minimal increase of SNB angle (11 studies, MD = 0.62 degree/year, 95% CI: 0.36–0.88 degree/year), and small decrease of ANB angle (10 studies, MD = −1.14 degree/year, 95% CI: −1.52 to −0.77 degree/year) compared to untreated Class II patients. RFAs caused significant dentoalveolar changes (predominantly retroclination of the upper incisors) and significant soft tissue changes. Skeletal changes were more pronounced with the Twin Block appliance. Various patient- or appliance-related factors influenced the results of the subgroup analyses, while the sensitivity analyses indicated robustness. Existing evidence was inadequate to assess the long-term effectiveness of RFAs.
Conclusions: The short-term evidence indicates that RFAs are effective in improving Class II malocclusion, although their effects are mainly dentoalveolar, rather than skeletal.
European journal of orthodontics, Jan 13, 2014
Summary BACKGROUND/OBJECTIVE : Chondrogenesis is an integral part of endochondral bone formation,... more Summary BACKGROUND/OBJECTIVE : Chondrogenesis is an integral part of endochondral bone formation, by which the midline cranial base is developed. Reactive oxygen species (ROS) are required in chondrogenic differentiation and antioxidant enzymes regulate their levels. The aim of this study was to localize the antioxidant enzyme glutathione peroxidase 1 (Gpx1) at the spheno-occipital synchondrosis, as well as its effect on ROS challenge and its expression pattern in the course of differentiation. Gpx1 was semiquantified in immunohistochemically stained sections of spheno-occipital synchondroses of rats. The effect of Gpx1 on ROS-induced apoptosis was investigated by manipulating the expression of Gpx1 in ATDC5 cells. The temporal pattern of Gpx1 expression was determined during chondrocyte differentiation for 21 days in vitro. Proliferating chondrocytes exhibited the greatest Gpx1 immunoreactivity and hypertrophic ones the lowest (P = 0.02). Cells transfected with Gpx1-siRNA had the h...
The European Journal of Orthodontics, 2015
European journal of orthodontics, Jan 13, 2014
Summary OBJECTIVE : To assess the treatment effects of removable functional appliances (RFAs) in ... more Summary OBJECTIVE : To assess the treatment effects of removable functional appliances (RFAs) in treated versus untreated patients with Class II malocclusion by means of lateral cephalometric radiographs. Unrestricted electronic search of 18 databases and manual searches up to October 2013. Prospective randomized and non-randomized controlled trials reporting on cephalometric angular measurements of Class II patients treated with RFAs and their matched controls. Skeletal, dental, and soft tissue changes were annualized and stratified to short- and long-term effects. Methodological limitations were evaluated with the Cochrane Risk of Bias tool and the Downs and Black checklist. Mean differences (MDs) with their 95% confidence intervals (CIs) were calculated from random-effects meta-analyses. Patient- or appliance-related subgroup analyses and sensitivity analyses were performed with mixed-effects models. Seventeen studies were included (1031 patients; mean age: 10.6 years), with most...
Orthodontics & Craniofacial Research, 2014
The aim of this study was to investigate the effect of interproximal enamel reduction (IER) on to... more The aim of this study was to investigate the effect of interproximal enamel reduction (IER) on tooth surfaces regarding the level of enamel roughness after applying different IER methods and the caries risk of treated teeth. Seven electronic databases were systematically searched. Two independent reviewers rated the articles at every step according to predetermined eligibility criteria. Data on enamel roughness were pooled if the same IER method was used and arithmetic values were available. Data on occurrence of caries were suitable for the analysis if the same units for caries development were used. From 2396 citations initially identified, 18 articles met the inclusion criteria and were further considered (14 studying enamel roughness and four studying the risk of caries after IER). A meta-analysis of quantitative data regarding enamel roughness was not possible due to statistical heterogeneity; instead, the enamel roughness findings are only described. The meta-analysis of studies focusing on the incidence of caries revealed no statistical difference between treated and untreated enamel surfaces (p = NS) from 1 to 7 years after IER. Drawing reliable conclusions on enamel roughness after IER is difficult owing to the diversity of the available studies. Statistically, the occurrence of caries on surfaces previously treated with IER was the same as that on intact surfaces, indicating that IER does not increase the risk of caries on treated teeth.
Clinical Oral Investigations, 2013
This study aims to demonstrate in vitro the synergistic effect of orthodontic forces and periodon... more This study aims to demonstrate in vitro the synergistic effect of orthodontic forces and periodontal pathogens on cyclooxygenase-2 regulation and the subsequent receptor activator of nuclear factor kappa-B ligand (RANKL) production from periodontal ligament (PDL) cells. In comparison to a control group, three experimental groups were formed from human primary PDL cells stressed with compressive forces, bacterial endotoxins, or a combination of both. Gene expression of cyclooxygenase-2 and RANKL was analysed with RT real-time PCR. The prostaglandin E2 production was determined with ELISA. A co-culture of PDL cells and an osteoclast-progenitor cell line was used in order to demonstrate the osteoclast formation effect caused by the simultaneous combined stress. The simultaneous combined stress resulted in a 56-fold up-regulation of cyclooxygenase-2 gene expression with a subsequent noticeable rise in the prostaglandin E2 in the culture medium. The RANKL/osteoprotegerin gene expression ratio was 50-fold up-regulated and the osteoclast formation assay revealed 153.5 ± 15.7 tartrate-resistant acid phosphatase (TRAP)-positive cells per well compared with 42.3 ± 3.8 TRAP-positive cells per well of the control group. The synergistic action of periodontal pathogens and orthodontic forces leads to an increased expression of cyclooxygenase-2 from PDL cells that intensify the RANKL production which in turn induces osteoclast differentiation and subsequent osteoclastogenesis. The present study puts an emphasis on the detrimental effect of orthodontic forces on patients with an active periodontal disease by underlining the significance of cyclooxygenase-2 activity and RANKL binding on the osteoclastogenesis process.
Aim: The validity of meta-analysis is dependent upon the quality of included studies. Here, we in... more Aim: The validity of meta-analysis is dependent upon the quality of included studies. Here, we investigated whether the design of untreated control groups (i.e. source and timing of data collection) influences the results of clinical trials in orthodontic research. Materials and methods: This meta-epidemiological study used unrestricted literature searching for meta-analyses in orthodontics including clinical trials with untreated control groups. Differences in standardized mean differences (ΔSMD) and their 95% confidence intervals (CIs) were calculated according to the untreated control group through multivariable random-effects meta-regression controlling for nature of the interventional group and study sample size. Effects were pooled with random-effects synthesis, followed by mixed-effect subgroup and sensitivity analyses. Results: Studies with historical control groups reported deflated treatment effects compared to studies with concurrent control groups (13 meta-analyses; ΔSMD = −0.31; 95% CI = −0.53, −0.10; P = 0.004). Significant differences were found according to the type of historical control group (based either on growth study or clinical archive; 11 meta-analyses; ΔSMD = 0.40; 95% CI = 0.21, 0.59; P < 0.001). Conclusions: The use of historical control groups in orthodontic clinical research was associated with deflation of treatment effects, which was independent from whether the interventional group was prospective or retrospective and from the study's sample size. Caution is warranted when interpreting clinical studies with historical untreated control groups or when interpreting systematic reviews that include such studies.
Orthodontics deals with the correction of skeletal anomalies of the face occurring in the form of... more Orthodontics deals with the correction of skeletal anomalies of the face occurring in the form of jaw discrepancies. There is an abundance of findings in the literature that the development and growth of the cranial base influence facial shape and jaw discrepancies. Cranial base develops by the mechanism of endochondral ossification taking place at its midline axis, where all the synchondroses are located. Chondrogenesis is the initial and indispensable part of endochondral bone formation. In the light of evidence underlying the need of reactive oxygen species in the regulation of chondrogenesis, this study aimed to investigate the ubiquitously present antioxidant enzyme Gpx1 and its contribution to redox regulation in chondrogenesis. Provided that the levels of oxidative stress were previously found to fluctuate according to the differentiation stage of chondrocytes, the gene expression of Gpx1 was measured with quantitative RT-PCR during chondrogenic differentiation. For this purp...
Journal of Clinical Medicine
The aim of this systematic review is to compare the effect on the upper airways of orthopedic tre... more The aim of this systematic review is to compare the effect on the upper airways of orthopedic treatment for skeletal Class III malocclusion with untreated controls. Nine databases were searched up to August 2020 for randomized or nonrandomized clinical trials comparing orthopedic Class III treatment (facemask or chin-cup) to untreated Class III patients. After duplicate study selection, data extraction, and risk of bias assessment (Risk Of Bias In Non-randomized Studies-of Interventions [ROBINS-I]), random-effects meta-analyses of Mean Differences (MDs)/Standardized Mean Differences (SMD) and 95% Confidence Intervals (CIs) were performed, followed by the Grading of Recommendations Assessment, Development and Evaluation assessment evidence-quality. A total of 10 papers (9 unique nonrandomized studies) with 466 patients (42.7% male; average age 9.1 years) were finally included. Limited evidence indicated that compared to normal growth, maxillary protraction with facemask was associate...
Progress in Orthodontics
Objectives Adults with fixed orthodontic appliances are increasing nowadays. Compared with adoles... more Objectives Adults with fixed orthodontic appliances are increasing nowadays. Compared with adolescents, adults present biological differences that might influence treatment duration. Therefore, the aim of the study was to compare duration of treatment with fixed appliances between adults and adolescents. Materials and methods Eight databases were searched up to September 2019 for randomized and non-randomized clinical studies comparing treatment duration with fixed appliances in adolescents and adult patients. After duplicate study selection, data extraction, and risk of bias assessment with the Cochrane ROBINS-I tool, random effects meta-analyses of mean differences (MD) and their 95% confidence intervals (CIs) were performed, followed by assessment of the quality of evidence with GRADE. Results A total of 11 unique studies (one prospective and 10 retrospective non-randomized) with 2969 adolescents and 1380 adult patients were finally included. Meta-analysis of 7 studies found no s...
The Angle Orthodontist
Objective: To investigate changes in dental arch configuration, relationship, and malocclusion di... more Objective: To investigate changes in dental arch configuration, relationship, and malocclusion directly after Class II malocclusion treatment with a Balters bionator modified by Ascher as well as 20 years after treatment. Materials and Methods: Orthodontic dental cast analysis of 18 patients with skeletal Class II treated with a bionator without any additional fixed therapy was performed with a digital caliper at three stages: before (T0), after (T1) and 20 years after (T2) treatment. Arch perimeter and depth, intermolar and intercanine distance, overjet, overbite, sagittal molar and canine relationship, mandibular incisor irregularity (Little's index), and malocclusion (PAR index) were assessed. Results: During treatment (T0–T1), upper arch perimeter significantly increased with a significant decrease in the upper and lower arch perimeter long-term (T1–T2), whereas corresponding arch depths changed only slightly in both periods. Transverse intermolar width increased significant...
Clinical Oral Investigations
ObjectiveTo investigate if orthodontic model analysis with a digital caliper can be interchangeab... more ObjectiveTo investigate if orthodontic model analysis with a digital caliper can be interchangeably performed between plaster and printed dental models.Materials and methodsForty-eight plaster models were digitized with orthoX®scan (DENTAURUM) and 48 counterparts were printed with Objet30 Dental Prime (Stratasys). One examiner performed five repeated orthodontic model analyses (41 outcomes) with a digital caliper in each plaster and the corresponding printed model and was externally validated by a second examiner. Inter- and intra-examiner reliability and error were evaluated with intraclass correlation coefficients (ICCs) and Dahlberg’s formula, intra-examiner agreement with Bland-Altman analyses and Lin’s correlation coefficients (CCCs), and changing bias with regression analyses.ResultsInter- and intra-examiner ICCs and Dahlberg’s error were ≥ 0.75 and ≤ 0.5 mm, respectively, for most outcomes in both plaster and printed models. Intra-examiner agreement (systematic bias) between plaster and printed models ranged from − 0.45 to 0.45 mm. Ranges of limits of agreement were wide for cumulative outcomes, such as crowding maxilla and mandible (2.69 mm and 3.07 mm around zero, respectively). Tooth widths were measured slightly larger in printed models. Lin’s CCCs were ≥ 0.87 for all the outcomes between plaster and printed models, while no changing bias was detected.ConclusionIf orthodontic model analyses are consistently performed, plaster casts and their corresponding printed models obtained with orthoX®scan and Objet30 Dental Prime can be interchangeably used for clinical purposes in orthodontics.Clinical relevanceOrthodontic model analysis is important in treatment planning and printed dental models need to be validated regarding this diagnostic procedure.
Deutsches Arzteblatt international, Jan 23, 2018
The effectiveness of intraoral appliances (IOA), maxillary expansion (ME), and maxillomandibular ... more The effectiveness of intraoral appliances (IOA), maxillary expansion (ME), and maxillomandibular advancement (MMA) in the treatment of children and adults with obstructive sleep apnea (OSA) has not yet been adequately assessed. An umbrella review was performed based on established guidelines for evidence-based medicine. Data synthesis was performed only from randomized controlled trials with Paule-Mandel random-effects meta-analyses / meta-regressions using mean differences (MDs) and 95% confidence intervals (CIs) and was followed by the qualitative evaluation of the meta-evidence. 29 systematic reviews were included, 7 of which provided quantitative data. IOA were effective in improving apnea hypopnea index (AHI) compared to both, placebo appliances (12 trials; 525 patients; MD = -11.70; 95% CI: [-15.38; -8.01]; p<0.001) and no treatment (1 trial; 24 patients; MD = -14.30; [-21.59; -7.01]; p<0.001). Only the former comparison was supported by robust meta-evidence. Effectivene...
Treatment effects of removable functional appliances in patients with Class II malocclusion: a sy... more Treatment effects of removable functional appliances in patients with Class II malocclusion: a systematic review and meta-analysis
Summary Objective: To assess the treatment effects of removable functional appliances (RFAs) in t... more Summary
Objective: To assess the treatment effects of removable functional appliances (RFAs) in treated versus untreated patients with Class II malocclusion by means of lateral cephalometric radiographs.
Search methods: Unrestricted electronic search of 18 databases and manual searches up to October 2013.
Selection criteria: Prospective randomized and non-randomized controlled trials reporting on cephalometric angular measurements of Class II patients treated with RFAs and their matched controls.
Data collection and analysis: Skeletal, dental, and soft tissue changes were annualized and stratified to short- and long-term effects. Methodological limitations were evaluated with the Cochrane Risk of Bias tool and the Downs and Black checklist. Mean differences (MDs) with their 95% confidence intervals (CIs) were calculated from random-effects meta-analyses. Patient- or appliance-related subgroup analyses and sensitivity analyses were performed with mixed-effects models.
Results: Seventeen studies were included (1031 patients; mean age: 10.6 years), with most of them originating from university clinics and reporting short-term effects (directly after the removal of RFAs). Treatment was associated with minimal reduction of SNA angle (11 studies, MD = −0.28 degree/year, 95% CI: −0.44 to −0.12 degree/year), minimal increase of SNB angle (11 studies, MD = 0.62 degree/year, 95% CI: 0.36–0.88 degree/year), and small decrease of ANB angle (10 studies, MD = −1.14 degree/year, 95% CI: −1.52 to −0.77 degree/year) compared to untreated Class II patients. RFAs caused significant dentoalveolar changes (predominantly retroclination of the upper incisors) and significant soft tissue changes. Skeletal changes were more pronounced with the Twin Block appliance. Various patient- or appliance-related factors influenced the results of the subgroup analyses, while the sensitivity analyses indicated robustness. Existing evidence was inadequate to assess the long-term effectiveness of RFAs.
Conclusions: The short-term evidence indicates that RFAs are effective in improving Class II malocclusion, although their effects are mainly dentoalveolar, rather than skeletal.
European journal of orthodontics, Jan 13, 2014
Summary BACKGROUND/OBJECTIVE : Chondrogenesis is an integral part of endochondral bone formation,... more Summary BACKGROUND/OBJECTIVE : Chondrogenesis is an integral part of endochondral bone formation, by which the midline cranial base is developed. Reactive oxygen species (ROS) are required in chondrogenic differentiation and antioxidant enzymes regulate their levels. The aim of this study was to localize the antioxidant enzyme glutathione peroxidase 1 (Gpx1) at the spheno-occipital synchondrosis, as well as its effect on ROS challenge and its expression pattern in the course of differentiation. Gpx1 was semiquantified in immunohistochemically stained sections of spheno-occipital synchondroses of rats. The effect of Gpx1 on ROS-induced apoptosis was investigated by manipulating the expression of Gpx1 in ATDC5 cells. The temporal pattern of Gpx1 expression was determined during chondrocyte differentiation for 21 days in vitro. Proliferating chondrocytes exhibited the greatest Gpx1 immunoreactivity and hypertrophic ones the lowest (P = 0.02). Cells transfected with Gpx1-siRNA had the h...
The European Journal of Orthodontics, 2015
European journal of orthodontics, Jan 13, 2014
Summary OBJECTIVE : To assess the treatment effects of removable functional appliances (RFAs) in ... more Summary OBJECTIVE : To assess the treatment effects of removable functional appliances (RFAs) in treated versus untreated patients with Class II malocclusion by means of lateral cephalometric radiographs. Unrestricted electronic search of 18 databases and manual searches up to October 2013. Prospective randomized and non-randomized controlled trials reporting on cephalometric angular measurements of Class II patients treated with RFAs and their matched controls. Skeletal, dental, and soft tissue changes were annualized and stratified to short- and long-term effects. Methodological limitations were evaluated with the Cochrane Risk of Bias tool and the Downs and Black checklist. Mean differences (MDs) with their 95% confidence intervals (CIs) were calculated from random-effects meta-analyses. Patient- or appliance-related subgroup analyses and sensitivity analyses were performed with mixed-effects models. Seventeen studies were included (1031 patients; mean age: 10.6 years), with most...
Orthodontics & Craniofacial Research, 2014
The aim of this study was to investigate the effect of interproximal enamel reduction (IER) on to... more The aim of this study was to investigate the effect of interproximal enamel reduction (IER) on tooth surfaces regarding the level of enamel roughness after applying different IER methods and the caries risk of treated teeth. Seven electronic databases were systematically searched. Two independent reviewers rated the articles at every step according to predetermined eligibility criteria. Data on enamel roughness were pooled if the same IER method was used and arithmetic values were available. Data on occurrence of caries were suitable for the analysis if the same units for caries development were used. From 2396 citations initially identified, 18 articles met the inclusion criteria and were further considered (14 studying enamel roughness and four studying the risk of caries after IER). A meta-analysis of quantitative data regarding enamel roughness was not possible due to statistical heterogeneity; instead, the enamel roughness findings are only described. The meta-analysis of studies focusing on the incidence of caries revealed no statistical difference between treated and untreated enamel surfaces (p = NS) from 1 to 7 years after IER. Drawing reliable conclusions on enamel roughness after IER is difficult owing to the diversity of the available studies. Statistically, the occurrence of caries on surfaces previously treated with IER was the same as that on intact surfaces, indicating that IER does not increase the risk of caries on treated teeth.
Clinical Oral Investigations, 2013
This study aims to demonstrate in vitro the synergistic effect of orthodontic forces and periodon... more This study aims to demonstrate in vitro the synergistic effect of orthodontic forces and periodontal pathogens on cyclooxygenase-2 regulation and the subsequent receptor activator of nuclear factor kappa-B ligand (RANKL) production from periodontal ligament (PDL) cells. In comparison to a control group, three experimental groups were formed from human primary PDL cells stressed with compressive forces, bacterial endotoxins, or a combination of both. Gene expression of cyclooxygenase-2 and RANKL was analysed with RT real-time PCR. The prostaglandin E2 production was determined with ELISA. A co-culture of PDL cells and an osteoclast-progenitor cell line was used in order to demonstrate the osteoclast formation effect caused by the simultaneous combined stress. The simultaneous combined stress resulted in a 56-fold up-regulation of cyclooxygenase-2 gene expression with a subsequent noticeable rise in the prostaglandin E2 in the culture medium. The RANKL/osteoprotegerin gene expression ratio was 50-fold up-regulated and the osteoclast formation assay revealed 153.5 ± 15.7 tartrate-resistant acid phosphatase (TRAP)-positive cells per well compared with 42.3 ± 3.8 TRAP-positive cells per well of the control group. The synergistic action of periodontal pathogens and orthodontic forces leads to an increased expression of cyclooxygenase-2 from PDL cells that intensify the RANKL production which in turn induces osteoclast differentiation and subsequent osteoclastogenesis. The present study puts an emphasis on the detrimental effect of orthodontic forces on patients with an active periodontal disease by underlining the significance of cyclooxygenase-2 activity and RANKL binding on the osteoclastogenesis process.
Aim: The validity of meta-analysis is dependent upon the quality of included studies. Here, we in... more Aim: The validity of meta-analysis is dependent upon the quality of included studies. Here, we investigated whether the design of untreated control groups (i.e. source and timing of data collection) influences the results of clinical trials in orthodontic research. Materials and methods: This meta-epidemiological study used unrestricted literature searching for meta-analyses in orthodontics including clinical trials with untreated control groups. Differences in standardized mean differences (ΔSMD) and their 95% confidence intervals (CIs) were calculated according to the untreated control group through multivariable random-effects meta-regression controlling for nature of the interventional group and study sample size. Effects were pooled with random-effects synthesis, followed by mixed-effect subgroup and sensitivity analyses. Results: Studies with historical control groups reported deflated treatment effects compared to studies with concurrent control groups (13 meta-analyses; ΔSMD = −0.31; 95% CI = −0.53, −0.10; P = 0.004). Significant differences were found according to the type of historical control group (based either on growth study or clinical archive; 11 meta-analyses; ΔSMD = 0.40; 95% CI = 0.21, 0.59; P < 0.001). Conclusions: The use of historical control groups in orthodontic clinical research was associated with deflation of treatment effects, which was independent from whether the interventional group was prospective or retrospective and from the study's sample size. Caution is warranted when interpreting clinical studies with historical untreated control groups or when interpreting systematic reviews that include such studies.