0000000000063946
AUTHOR
Andrej Zentner
showing 26 related works from this author
Efficacy of protection by latex gloves during orthodontic therapy.
2000
The wearing of gloves during orthodontic or dental treatment is generally indicated for reasons of hygiene and protection against infection. This study was aimed at determining the extent and localization of perforations caused by the various orthodontic treatment techniques and interrupting the infection barrier. The impermeability was tested by means of a water retention test according to European standard EN 455, Part 1, performed on 1600 Centramed (Centramed, Koblenz), Tekmedic and SafeEx non-sterile disposable latex gloves (both by Safe Med, Switzerland) and Safe Gan latex gloves with an additional acrylate coating (also by Safe Med). The perforation rate in unused gloves was between 0…
Proliferative response of cells of the dentogingival junction to mechanical stimulation
2001
SUMMARY The aim of this research was to study the proliferative response of junctional epithelium (JE) and gingival connective tissue (GCT) to mechanical stimulation in vivo with regard to the potential occurrence of apical migration of JE and loss of GCT attachment during orthodontic tooth movement. Elastic bands were inserted between the maxillary first and second molars of male rats aged 8 weeks, which were pulse-labelled with 3 H-thymidine and subsequently killed in groups, together with labelled control animals (a total of 98 rats) after periods of 1‐168 hours. Autoradiographs were prepared from plastic mesiodistal sections, and parameters of cell proliferation for JE and GCT of the pa…
Predictive value of morphologic parameters for successful correction of Class II Division 2 malocclusion
2003
Abstract The aim of this study was to assess the predictive value of pretreatment cephalometric parameters and apical base size for successful correction of Angle Class II Division 2 malocclusion. Pretreatment lateral cephalograms and pretreatment and posttreatment study casts of 96 subjects with Class II Division 2 malocclusions were examined to obtain 23 cephalometric parameters and to measure the size of the apical bases. Success of occlusal correction was evaluated as the percentage of change of peer assessment rating scores during treatment; percentage of change was the dependent variable in multivariate statistical analyses used to test the predictive value of the assessed parameters.…
Perception of Occlusion, Psychological Impact of Dental Esthetics, History of Orthodontic Treatment and Their Relation to Oral Health in Naval Recrui…
2007
Abstract Objective: To investigate whether the oral health of young male adults was related to (1) the degree of self-perceived malocclusion, (2) the degree of experienced negative psychosocial impact of dental esthetics, and (3) the history of orthodontic treatment and its duration. Materials and Methods: The study subjects were 470 male naval recruits undergoing a routine dental health checkup. They answered the Perception of Occlusion Scale (POS) and Negative Impact of Dental Aesthetics Scale (NIDAS). The Approximal Plaque Index (API), the Sulcus Bleeding Index (SBI), and the number of decayed teeth (DT) and missing teeth (MT) were examined by a staff dentist. Statistical procedures were…
Size discrepancy of apical bases and treatment success in angle Class III malocclusion.
2001
The aim of this retrospective clinical study was to measure the apical bases and determine their size relationship in Class III malocclusion cases before and after orthodontic treatment, in order to evaluate their significance for the treatment success. Maxillary and mandibular apical bases were measured on study models of 104 Class III cases treated by conventional orthodontics, using a specifically constructed conveyance apparatus, and related to each other as an index. Treatment success was quantitatively assessed as the percentage change of PAR scores obtained from the pretreatment and posttreatment study models. Statistically significant relationships were disclosed between the measure…
Absence of binding of human salivary glycoprotein to human gingival fibroblast-like cells in vitro.
1996
The aim of this study was to determine whether human high molecular weight salivary glycoprotein binds in vitro to human gingival fibroblast-like cells. Primary monolayer cultures of 2 human gingival fibroblast-like cell lines were incubated with a high molecular weight fraction of salivary glycoprotein which expressed blood group A activity and glycoprotein-cell binding probed using an FITC-conjugated mouse monoclonal antibody to human blood group A antigen. Surface fluorescence of protein-treated cells was found to be no greater than that of untreated or serum-treated control cultures. As significant binding of salivary glycoprotein to gingival fibroblast-like cells does not occur in vitr…
Predicting patient compliance in orthodontic treatment
2000
Abstract This article reviews the current knowledge regarding prediction of patientcompliance during orthodontic treatment. Relevant literature dealing with this and other related aspects of patient compliance is discussed, and an attempt is made to structure and summarize available information. The multifacetted nature of this issue is emphasized, existing controversies highlighted, and where appropriate, practical suggestions are made.
A comparative assessment of acceptance of different types of functional appliances
1998
Patients' acceptance of an orthodontic appliance may influence compliance and thus contribute to a successful outcome of treatment. The aim of this study was to assess the influence of shape and design of different types of functional appliances on their acceptance by patients. For each of 10 adult volunteer subjects employed in the study eight different functional appliances were fabricated which had a varying extension of the resin base and amount of interocclusal opening. Effects of appliances on speech, initial acceptance, and acceptance after wearing were assessed by means of standardized tests. Amongst the appliances tested the bionator, functional corrector FR-I and elastic open acti…
Early Cellular Reactions in Mechanically Stimulated Gingival Connective Tissue
2001
Aim: The aim of this study was to describe early cellular reactions occuring in mechnically stimulated gingival connective tissue. Material and Method: Elastic bands were inserted between the maxillary first and second molars of male rats aged 8 weeks, which were pulse-labeled with 3H-thymidine and subsequently killed in groups together with labeled control animals after periods of 1–168 hours. Autoradiographs were prepared from plastic mesiodistal sections and parameters of cell proliferation determined in gingival connective tissue sampling areas coronal to the interdental bone crest and in the central zone of the body of the papilla between the second and third molars. The incidence of m…
Development of a questionnaire for assessment of the psychosocial impact of dental aesthetics in young adults
2006
The aim of this study was to develop a psychometric instrument for assessment of orthodontic-specific aspects of quality of life. The study subjects, 194 young adults aged 18-30 years, were interviewed using a pool of 23 items dealing with the psychosocial impact of dental aesthetics. Self- and interviewer-rating of the dental aesthetic appearance of each subject were carried out using the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN). Additionally, the Perception of Occlusion Scale and a modification of the Dental Aesthetic Index (DAI) were applied. Factorial analyses identified four measures within the item pool, namely Dental Self-Confidence, Social Impact, P…
Strukturelle Veränderungen in säuregeätztem Schmelz im konfokalen Laser-Scanning-Mikroskop
1996
The aim of the present investigation was to elucidate structural alternations in enamel subjected to acid etch technique and treatment under remineralizing conditions by means of a new microscopy technique known as confocal laser scanning microscopy (CLSM). Blocks of enamel were treated with 37% phosphoric acid and exposed for 3 weeks to an oral environment. Tomographic CLSM images were subsequently obtained and compared with controls. CLSM proved to be a reliable, highly reproducible and simple method of qualitative assessment of structural changes occurring on the surface of enamel and in areas below the surface as deep as 100 microns or more. Structural alterations associated with acid a…
Effects of mechanical stimulation on cell cycle duration in rat gingival fibroblast progenitor cells
2001
The aim of this investigation was to estimate cell cycle duration in rat gingival fibroblast progenitor cells in steady-state control and during sustained mechanical stimulation. Elastics (0.15 mm thick) were inserted between maxillary M1 and M2 of 8 wk-old male rats which were labelled with H3-TdR and killed in groups of 6-7 animals together with equal-sized groups of labelled control animals at intervals between 1-168 h. Autoradiographs of consecutive mesio-distal sections were used to determine grain counts for H3-TdR-labelled cells in the connective tissue of the gingival papilla between M2 and M3. Median cell cycle times (MCC) were estimated from plots of mean and median grain counts a…
Holographische Untersuchung zur Darstellung initialer Verformungen eines mazerierten menschlichen Schädels unter der Einwirkung einer orthopädischen …
1995
Das Phanomen der Oberkieferverformung und der resultierenden Wachstumsveranderungen unter der orthopadischen Wirkung des Headgears ist sehr komplex und wenig erforscht. Ziel der vorliegenden Arbeit war es, mit Hilfe der holographischen Interferometrie die initiale Knochenverformung des Oberkieferkomplexes nach der Einwirkung verschiedener Zugrichtungen eines Headgears zu untersuchen. Ein oberhalb, unterhalb und durch das Widerstandszentrum der ersten bleibenden Molaren gerichteter okzipitaler, zervikaler und Kombinationszug wurde mit 560 g an einem mazerierten menschlichen Schadel simuliert. Die Registrierung der dabei stattfindenden knochernen Veranderungen fand mit Hilfe der Laserholograp…
Relationship between Patient Discomfort, Appliance Acceptance and Compliance in Orthodontic Therapy
2000
Orthodontic treatment is occasionally a discomfort to patients, due to pain or functional restrictions. In this context, several retrospectively planned studies were performed in the 1980s, but correlations between different aspects of patient discomfort were not investigated. The present study aimed at examining and structuring the psychogenic dimensions of patient discomfort. Furthermore, the impact of the patient's attitude on the intensity of discomfort was to be evaluated in addition to the influences of appliance therapy. The study was performed with 67 patients aged from 9 to 32 years. Prior to insertion of a new appliance, psychogenic scales reflecting their attitude towards orthodo…
Dental aesthetics, self-awareness, and oral health-related quality of life in young adults.
2004
The aim of the present study was to explore the putative relationship between dental aesthetics and oral health-related quality of life (OHRQoL), taking into consideration the potential direct and moderating influence of private and public self-consciousness. The subjects of this cross-sectional survey were 148 university students. Dental aesthetics were assessed by means of the aesthetic component (AC) of the Index of Orthodontic Treatment Need (IOTN). OHRQoL was estimated using a modification of the scales 'social appearance concern' and 'appearance disapproval', and a novel dental self-confidence scale. In addition, the private and public self-consciousness scales were used. Two-factor a…
Surgically Assisted Rapid Palatal Expansion An Acoustic Rhinometric, Morphometric and Sonographic Investigation
2001
This study aimed to evaluate the effect of surgically assisted rapid palatal expansion on the skeletal structures of the midface. Ten patients (mean age 28.5 years) were investigated by means of acoustic rhinometry, study model analysis and sonography before and after the procedure of surgically assisted rapid palatal expansion. The measurements revealed that surgically assisted rapid palatal expansion not only resulted in transverse expansion of the maxilla, providing dental arch space for lining up the teeth; the procedure also caused a substantial enlargement of the maxillary apical base and of the palatal vault, providing space for the tongue for correct swallowing and thus preventing r…
Eine In-vitro-Untersuchung zweier in der Kieferorthopädie verwendeter Kunststoffe auf Zelltoxizität
1994
Ziel der vorliegenden In-vitro-Untersuchung war eine Uberprufung der in der Kieferorthopadie verwendeten Kunststoffe Orthocryl® (Dentaurum) und Wil-o-dont® (Wilde) auf Zellvertraglichkeit mit Hilfe des vonHeidemann u. Lampert [2] beschriebenen Verfahrens. Die akute lokale unspezifische Zelltoxizitat dieser Materialien und ihrer Einzelkomponenten wurde durch eine qualitative mikroskopische Begutachtung eintretender zytopathologischer Veranderungen in den neben den Prufkorpern kultivierten menschlichen Gingivafibroblasten sowie durch eine semiquantitative Beurteilung der Grose der um die getesteten Materialien entstandenen Hemmzonen des Zellwachstums evaluiert. Wahrend Orthocryl® und seine ge…
Pain and discomfort during orthodontic treatment: causative factors and effects on compliance.
1998
Orthodontic patients experience pain and discomfort to a varying degree during the course of treatment. The aims of the present investigation were to follow the progress of adaptation after insertion of new appliances and to study the relationships between the type of appliance worn and pain or discomfort experienced, between pain sensations and attitude toward the treatment and their effects on patients' compliance. Pain and discomfort experienced by 84 patients undergoing orthodontic treatment, their attitude toward the treatment, and compliance were assessed 7 days, 14 days, 6 weeks, 3 months, and 6 months after appliance insertion, using specially designed protocols, questionnaires, and…
Covalent RGD modification of the inner pore surface of polycaprolactone scaffolds
2011
Scaffold production for tissue engineering was demonstrated by means of a hot compression molding technique and subsequent particulate leaching. The utilization of spherical salt particles as the pore-forming agent ensured complete interconnectivity of the porous structure. This method obviated the use of potentially toxic organic solvents. To overcome the inherent non-cell-adhesive properties of the hydrophobic polymer polycaprolactone (PCL) surface activation with a diamine was performed, followed by the covalent immobilization of the adhesion-promoting RGD-peptide. The wet-chemical approach was performed to guarantee modification throughout the entire scaffold structure. The treatment wa…
Morphological parameters as predictors of successful correction of Class III malocclusion
2001
The aim of the study was to assess pre-treatment cephalometric parameters and measurements of the size of the apical bases as predictors of successful orthodontic correction of Class III malocclusions. Pre- and post-treatment lateral cephalograms and study models of 80 completed Class III subjects were examined to obtain 23 cephalometric parameters taken mainly from the analyses of McNamara and Schwarz, and to measure the size of the apical bases. Success of occlusal correction was evaluated as the percentage change of peer assessment rating score during treatment, which was used as the dependent variable in multivariate statistical analyses testing the predictive value of the parameters as…
An experimental study of the esthetic effect of facial profiles
1998
In this study good-looking "male" and "female" as well as ugly facial profiles were shaped by 104 lay persons using an especially constructed device according to specific instructions. These profiles were photographed and subsequently evaluated using a series of parameters from soft tissue profile analyses. Although some significant mean value differences were found between the good-looking and ugly profile variants, they were not substantial. In contrast, markedly significant differences were revealed between the variances of all variables. In some instances the variance of the ugly profiles was more than 3 to 4 times higher than that of the good-looking profiles. These findings were convi…
Dentofacial aesthetics and quality of life
2007
This article reviews, from the socio-psychological perspective on physical attractiveness, recent research on the psychosocial impacts of dental aesthetics. Research on personal impression forming suggests that visual perceptions of detrimental dental conditions might lead to conclusions about social impairments of the target person. Consumers conform considerably with professional assessment of dental aesthetics. Psychosocial impacts of dental appearance in childhood include teasing by peers. Existing research suggests that dental aesthetics contributes to psychosocial well-being of both children and adults. The concept of public self-consciousness is introduced for explaining differences …
Reliability and validity of the Digigraph 100 in orthodontic diagnosis.
2001
Cephalometric analyses of lateral cephalograms allow important statements to be made on diagnosis and treatment planning. Such radiographs should, however, be taken with a considerable reduction in radiation exposure. With the Digigraph 100 (Dolphin Imaging Systems Inc., USA) a cephalometric technique based on distance measurements of emitted sonic signals is now available. This study was aimed at determining the degree to which this procedure can cope with the requirements of reliability and validity in the field of orthodontics. For this purpose 50 volunteers were examined by conventional cephalometry with manual tracing of lateral cephalograms as well as by sonic cephalometry, with Jarab…
Ein zahngrößen- und gesichtsbreitenbezogener Zahnbogenindex
1994
Taking as its starting point the often postulated criticism of Pont's Index, the intent of the study was to develop a diagnostic procedure which took into consideration the objection that the Pont Index doesn't take the shape of the patient's skull into consideration. On the basis of the data obtained from the models and anthropological measurements of 50 adult subjects with fairly eugnathic dentition, the first step was to follow Pont and study which skull size exhibited the highest correlation to the posterior dental arch. Of all the relevant sizes the zygomatic arch width exhibited the highest correlation. Reference values for the posterior dental arch width, which were obtained with the…
Functional and social discomfort during orthodontic treatment--effects on compliance and prediction of patients' adaptation by personality variables.
2000
During the course of treatment orthodontic patients frequently endure a number of functional complaints and are anxious about their appearance. The aims of this longitudinal study were to follow the progress of patients' adaptation to discomfort, to elucidate the putative relationship between the type of appliance worn and functional and social discomfort experienced, to study potential predictability by their attitude to treatment and to evaluate the effects of discomfort as predictors of patients' compliance. Eighty-four patients undergoing either removable, functional, or fixed appliance treatment monitored their complaints during the first 7 days of treatment and rated them retrospectiv…
Dental esthetics, orthodontic treatment, and oral-health attitudes in young adults.
2005
Introduction: The aim of this study was to investigate whether young adults with varying dental esthetics and histories of orthodontic treatment also differ in oral-health attitudes, preventive behaviors, and self-perceived oral health. Methods: The sample comprised 298 young adults, 18 to 30 years old, with at least 13 years of primary and secondary school education. The subjects were asked to complete questionnaires dealing with various measures related to oral-health attitudes, preventive behaviors, and perceptions of oral health. Dental esthetics were assessed by means of the aesthetic component of the index of orthodontic treatment need. Dental plaque accumulation was assessed in a sub…