Orthodontic findings in adults with Trisomy 21.

OBJECTIVES: Objective of this study was to describe orthodontic findings in adults with Down's syndrome, a matter insufficiently regarded in literature. MATERIALS AND METHODS: A group of 104 adults (33.8 ± 15 years) with trisomy 21 had an orthodontic check-up in their accustomed environment. Anamnestic and dental findings completed the examination and descriptive analysis was performed using SPSS23. Relative frequencies with 95% confidence intervals were compared to the average population (SHIP-study, 2003; DMS IV, 2006). RESULTS: Among the participants 46.2% (36.3-56.2%) (SHIP 36.7%) had already undergone orthodontic treatment. In 87.5% (79.6-93%) of the patients, less than 25.6 properly functioning permanent teeth (DMS IV's mean) were found. Gingival bleeding and recessions, as well as periodontal disease, were increasingly found in older affected persons. Patients with Down's syndrome showed less crowding, e.g., maxillary incisors 28% (19.3-39%) versus 41.9% (SHIP). Frontal open bite (35.2% (25.3-46.1%) versus 3.6% (SHIP)) and frontal crossbite (40.9% (30.5-51.9%) versus 4.2% (SHIP)) were more often observed. No considerable differences in frequencies of orthodontic findings were detected in the comparison of the subgroups "18-28 years" versus ">28 years", "with" versus "without orthodontic treatment", "male" versus "female", "with" versus "without periodontal problems", or "with" versus "without orofacial disturbances". CONCLUSIONS: Within the bounds of this study, we gathered orthodontic findings in adults with trisomy 21 for the first time. In comparison to the average population, the subject group showed a greater number of complex orthodontic findings. CLINICAL RELEVANCE: These persisting dental and orofacial problems must be considered when treating patients with Down's syndrome.

Clinical parameters and inflammatory biomarkers among patients with multibracket appliances: a prospective clinical trial.

BACKGROUND: Aim of the presented study was to investigate changes in clinical parameters and active matrix metalloproteinase-8 (aMMP-8) levels in gingival crevicular fluid of patients before and during treatment with multibrackets appliances. METHODS: Fifty-five adolescents scheduled for the treatment were included. Clinical parameters and subgingival samples were obtained at six time points: 1 week before appliance insertion (T0), 3 (T1), 6 (T2) weeks, 3 (T3), 6 (T4) months, and 1 year (T5) after that. Gingival index and plaque index were assessed to evaluated changes on the clinical status. Subgingival samples were collected to analyze changes in aMMP-8. RESULTS: Scores for gingival and plaque index increased after bracket insertion. The gingival index increased from T2 (p < 0.05) until T5 (p < 0.0001). Plaque index also increased, reaching its maximum peak at T3 (p < 0.05). Moreover, an increase of aMMP-8 levels (p < 0.05) was noted. There was no significant between upper and lower jaws. CONCLUSIONS: Treatment with multibracket appliances in adolescents favors dental plaque accumulation and may transitionally increase gingival and plaque index and aMMP-8 levels leading to gingival inflammation, even 1 year after therapy began. TRIAL REGISTRATION: This study was approved by the Ethics Committee of the dental medical association Rheiland-Pfalz, Germany (process no. 837.340.12 (8441-F)), and followed the guidelines of Good Clinical Practices.

Effect of the antirheumatic medication methotrexate (MTX) on biomechanical compressed human periodontal ligament fibroblasts (hPDLFs).

BACKGROUND: The aim of this study was to investigate the in vitro effect of the antirheumatic drug methotrexate (MTX) on biomechanically compressed human periodontal ligament fibroblasts (hPDLFs), focusing on the expression of interleukin 6 (IL-6), as its upregulation is relevant to orthodontic tooth movement. METHODS: Human PDLFs were subjected to pressure and simultaneously treated with MTX. Cell proliferation, viability and morphology were studied, as was the gene and protein expression of IL-6. RESULTS: Compared with that in untreated fibroblasts, IL-6 mRNA expression in mechanically compressed ligament fibroblasts was increased (two to sixfold; ****p < 0.0001). Under compression, hPDLFs exhibited a significantly more expanded shape with an increase of cell extensions. MTX with and without pressure did not affect IL-6 mRNA expression or the morphology of hPDLFs. CONCLUSION: MTX has no effect on IL-6 expression in compressed ligament fibroblasts.

Orthodontists' instructions for oral hygiene in patients with removable and fixed orthodontic appliances.

INTRODUCTION: The aim of this questionnaire-based survey was to evaluate information on frequencies, instructions and products relating to oral hygiene (OH) in orthodontic practices. METHODS: Using a computer-generated randomization list, 1000 orthodontists were selected and sent a questionnaire. The size and number of inhabitants of the federal states of Germany were considered. The federal states with the highest return rate (Baden-Wuerttemberg [BW], Bavaria [B], Hesse [H], Lower Saxony [LS], Nordrhein-Westphalia [NRW]) were considered and differences between the 16 federal states were divided into North, South, East and Central Germany. RESULTS: The response rate of the questionnaires was 52.4%. The majority (53.8%) worked in one practice alone. Most (59.1%) have been orthodontists for 5-25 years. For vestibular multibracket appliances (MBA) in BW, B, H and LS over 90% recommended interdental brushes (IDB). In NRW 91.4% recommend fluoride gel. In B and H more than 80% chose electric toothbrush (ETB), in BW, LS and NRW more than 80% manual toothbrush (MTB). For lingual MBA (LMBA) in BW, H, LS and NRW with approximately 50% each fluoride gel, IDB and MTB were chosen. In B fluoride gel, IDB and ETB. For removable apparatus (RA), five federal states recommended MTB (>80%) and ETB (BW, B, H > 80%; NRW > 70%; LS > 60%). CONCLUSION: Electric toothbrushes are recommended for the use with all appliances, only with removable appliances manual toothbrushes are favoured. For vestibular MBA it is strongly advised to use IDB additionally.

Orthodontic treatment in periodontally compromised patients: a systematic review.

OBJECTIVES: The aim of this systematic review was to examine the literature on aggressive and chronic periodontitis and orthodontics to clarify the therapy-relevant aspects of orthodontic treatment with altered biomechanics in periodontally compromised dentition. MATERIALS AND METHODS: Literature searches were conducted in the electronic databases "PubMed" and "DIMDI" using the keywords "aggressive periodontitis AND ortho*," "aggressive periodontitis AND orthodontics," "chronic periodontitis AND ortho*," and "chronic periodontitis AND orthodontics" for the publication period from January 1990 to July 2022. In addition, a manual search was carried out in the selected trade journals "Community Dental Health," "European Journal of Oral Sciences," and "Parodontologie." Human clinical trials were included, whereas animal experimental studies, case reports, and reviews were generally excluded. The appropriate studies were selected, and the relevant data was tabulated according to different parameters, regarding the study design, the study structure, and the conduct of the study. RESULTS: A total of 1067 articles were found in the preliminary electronic search. The manual search and review of all related bibliographies resulted in an additional 1591 hits. After the first screening, 43 articles were classified as potentially relevant and reviewed in their original form. After the suitability test, 5 studies with a total of 366 participants were included in the final evaluation. These included one randomized controlled trial and four low-evidence intervention studies. The studies were conducted in two university hospitals and three private practices. All participants underwent scaling and root plaining and periodontal surgery before the orthodontic treatment started. Mean probing pocket depth reduction before and after the interdisciplinary treatment was analyzed in all the included studies; mean difference in clinical attachment level in four of the studies was also included. All participants were enrolled in a continuous recall system. In all studies, orthodontic therapy in periodontally compromised patients improved function and esthetics, resulting in lower probing depths and clinical attachment gains. CONCLUSIONS: Orthodontic treatment can be used for patients with reduced periodontal support to stabilize clinical findings and improve function and esthetics. The prerequisite for this is a profound knowledge of altered biomechanics and an adapted interdisciplinary treatment approach. Due to the large heterogeneity of the included studies and their limited methodological quality, the results obtained in this review must be considered critically. Further randomized controlled long-term studies with comparable study designs are necessary to obtain reliable and reproducible treatment results. CLINICAL RELEVANCE: Patients with periodontal impairment can be successfully treated with orthodontics as part of interdisciplinary therapy. Orthodontic treatment has no negative impact on the periodontium; if minimal, controlled forces are used under non-inflammatory conditions.

Aligner therapy in adolescents: first-year results on the impact of therapy on oral health-related quality of life and oral hygiene.

OBJECTIVES: The aim of this multicenter clinical study was to examine the oral health-related quality of life and oral hygiene in adolescents before and during aligner therapy. MATERIALS AND METHODS: Forty subjects (18 ♀, 22 ♂; mean age: 13.6 years) scheduled for aligner therapy (Invisalign® Teen) were given oral health-related quality of life questionnaires, Oral Health Impact Profile (OHIP-G14) and Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ), to complete within their treatment (visit 1: 0 start of therapy; visit 2: 0 + 4 weeks; visit 3: 0 + 10 weeks; visit 4: 0 + 6 months; visit 5: 0 + 1 year). To assess oral hygiene, a questionnaire to take home was used, and plaque level was evaluated with the Quigley-Hein Plaque Index (TMQH) modified by Turesky et al. RESULTS: The OHIP-G14 mean score before aligner therapy was 3.3 ± 3.2, and 4.9 ± 5.4 after 1 year. The PIDAQ showed a positive psychological change in the well-being, as well as a more effective at-home oral hygiene regime. On average, the TMQH remained at a low level (grade 2 of 0-5). The initial insertion of the aligners caused the most significant changes in all parameters (except TMQH). CONCLUSION: Oral health-related quality of life is only slightly affected during the first year of aligner therapy in adolescents. Oral hygiene at home is intensified and there is no increased dental plaque accumulation. CLINICAL RELEVANCE: Dentofacial esthetics is a subset of the so-called Oral H-Related Quality of Life (OHRQoL) which should be considered more during orthodontic therapy.

Ergonomic Risk Assessment of Oral and Maxillofacial Surgeons - RULA Applied to Objective Kinematic Data.

BACKGROUND: The prevalence of musculoskeletal disorders is high in oral and maxillofacial surgeons (OS) due to their static and contorted working positions. Hence, the aim of this study was to conduct posture analyses in this specific group of dental professionals using the Rapid Upper Limb Assessment (RULA). METHODS: In total, 15 (12 m/3 f) OS participated in this study. An inertial motion capture system (Xsens) was used to collect kinematic data during a simulated workflow. Computer-based routines calculated the RULA score for the extracted joint angles at each defined time point. Then, an analysis of the time-dependent RULA scores by body regions was conducted. Key variables were the relative occurrence of specific RULA scores during the complete workflow, individual subtasks, and for treatment of each of the four different dental quadrants. The subtasks and dental quadrants were compared using the Friedman test. RESULTS: The total median RULA score represented a high risk for OS during their work (7), including the temporal component (OS spent 77.54% of their working time with a RULA score of 7). The wrists and hands, elbows, lower arms, and the neck were exposed to postures with the highest risk for musculoskeletal strain. DISCUSSION: For OS, both the right and the left assisting hand were heavily strained while working on the first dental quadrant caused the most unfavorable postures for OS.

Randomized multicenter study on the plaque removal efficacy of 2 interdental brushes around the base of orthodontic brackets.

INTRODUCTION: The objective of this multicenter study was to analyze the efficacy of cleaning 2 interdental brushes (IDBs) around brackets in patients with fixed orthodontic appliances. METHODS: The study design was a multicenter, randomized, examiner-blinded crossover study with 3 interventions, the first of which was a baseline intervention. This study included 20 patients (12 females, 8 males) aged 12-18 years with fixed orthodontic devices examined at the Department of Orthodontics, University Medical Center of the Johannes Gutenberg University Mainz, and the Children's Dental Clinic St. Gallen. The outcome was a conventional, cylindrically shaped IDB (IDBG-S [IB]; Top Caredent GmbH, Schönau, Germany) was examined in comparison with an innovative waist-shaped IDB (Circum, CDB-8 [CB]; Top Caredent GmbH). The participants did not use the IDB themselves. The brushing procedure was performed professionally by 1 operator (C.E.). Each buccal tooth surface with a bracket was split into 8 areas, the main areas being 1 and 8. These main areas, which were difficult for toothbrushes to reach, were mesial (area 1) and distal (area 8) of the bracket edges in the gingival direction. Plaque index (PI) scores were assessed at 2 examinations before and after the cleaning procedure on 8 tooth surfaces in the area with orthodontic brackets. A computer-generated program randomly allocated the IDB sequence to the participants. Examiners (L.Z.-G. and Y.W.) assessing the outcomes were blinded to the intervention and the randomized allocation of participants to the different IDBs. RESULTS: Both IDBs showed a plaque removal effect (CB, 0.68 [interquartile range, 0.63-0.77]; IB, 0.43 [interquartile range, 0.33-0.55]). The difference between the 2 IDB was statistically significant (P = 0.002). In particular, the CB yielded a higher plaque removal efficacy (CB effect, 0.68; IB effect, 0.21) at the main areas 1 and 8, which were difficult to reach. Ten participants were randomized to each sequence, and all 20 completed the study. No side effects or adverse events were reported or observed. CONCLUSION: The waist-shaped brush head of the CB significantly enhanced plaque reduction in total and particularly in problem areas. REGISTRATION: This trial was registered at the German Clinical Trials Registry (no. DRKS00014088; https://www.drks.de/drks_web/navigate.xxdo?navigationId=trial.HTML&TRIAL_ID=DRKS00014088) PROTOCOL: The protocol was not published before trial commencement. FUNDING: This study was supported by the manufacturer Top Caredent GmbH, Schönau, Germany, which provided all interdental brushes used in this study.

A RULA-Based Comparison of the Ergonomic Risk of Typical Working Procedures for Dentists and Dental Assistants of General Dentistry, Endodontology, Oral and Maxillofacial Surgery, and Orthodontics.

BACKGROUND: In general, the prevalence of work-related musculoskeletal disorders (WMSD) in dentistry is high, and dental assistants (DA) are even more affected than dentists (D). Furthermore, differentiations between the fields of dental specialization (e.g., general dentistry, endodontology, oral and maxillofacial surgery, or orthodontics) are rare. Therefore, this study aims to investigate the ergonomic risk of the aforementioned four fields of dental specialization for D and DA on the one hand, and to compare the ergonomic risk of D and DA within each individual field of dental specialization. METHODS: In total, 60 dentists (33 male/27 female) and 60 dental assistants (11 male/49 female) volunteered in this study. The sample was composed of 15 dentists and 15 dental assistants from each of the dental field, in order to represent the fields of dental specialization. In a laboratory setting, all tasks were recorded using an inertial motion capture system. The kinematic data were applied to an automated version of the Rapid Upper Limb Assessment (RULA). RESULTS: The results revealed significantly reduced ergonomic risks in endodontology and orthodontics compared to oral and maxillofacial surgery and general dentistry in DAs, while orthodontics showed a significantly reduced ergonomic risk compared to general dentistry in Ds. Further differences between the fields of dental specialization were found in the right wrist, right lower arm, and left lower arm in DAs and in the neck, right wrist, right lower arm, and left wrist in Ds. The differences between Ds and DAs within a specialist discipline were rather small. DISCUSSION: Independent of whether one works as a D or DA, the percentage of time spent working in higher risk scores is reduced in endodontologists, and especially in orthodontics, compared to general dentists or oral and maxillofacial surgeons. In order to counteract the development of WMSD, early intervention should be made. Consequently, ergonomic training or strength training is recommended.

Effects of Resistance Training as a Behavioural Preventive Measure on Musculoskeletal Complaints, Maximum Strength and Ergonomic Risk in Dentists and Dental Assistants.

INTRODUCTION: For dental professionals, musculoskeletal disorders (MSD) are common health hazards and resistance training programmes have been promising approaches in the quest for a reduction in the pain intensity of these professionals. Therefore, the aim of the current study was to investigate the effect of a trunk-oriented 10-week resistance training programme. METHOD: In total, the study was conducted with 17 dentists and dental assistants (3 m/14 f) over a course of 10 weeks, with workouts being performed 2 times a week using a 60 min intervention programme consisting of 11 resistance training exercises. The outcome values that were collected were the pain intensity (visual analogue scale (VAS) combined with a modified version of the Nordic Questionnaire), the MVIC and the rapid upper limb assessment (RULA) score (based on data from inertial motion units) during a standardised dental treatment protocol. RESULTS: A significant reduction in pain intensity was found for each queried body region: the neck, upper back, lower back and the right and left shoulders. The maximum voluntary isometric contraction (MVIC) improved significantly in all outcome measures: flexion, extension, right and left lateral flexion and right and left rotation. CONCLUSIONS: A 10-week resistance training programme for dentists and dental assistants had significant effects on pain intensity reduction and the MVIC of the musculature of the trunk and is, therefore, suitable as a behavioural preventive measure against MSD in dental professionals.

Combining Ergonomic Risk Assessment (RULA) with Inertial Motion Capture Technology in Dentistry-Using the Benefits from Two Worlds.

Traditional ergonomic risk assessment tools such as the Rapid Upper Limb Assessment (RULA) are often not sensitive enough to evaluate well-optimized work routines. An implementation of kinematic data captured by inertial sensors is applied to compare two work routines in dentistry. The surgical dental treatment was performed in two different conditions, which were recorded by means of inertial sensors (Xsens MVN Link). For this purpose, 15 (12 males/3 females) oral and maxillofacial surgeons took part in the study. Data were post processed with costume written MATLAB® routines, including a full implementation of RULA (slightly adjusted to dentistry). For an in-depth comparison, five newly introduced levels of complexity of the RULA analysis were applied, i.e., from lowest complexity to highest: (1) RULA score, (2) relative RULA score distribution, (3) RULA steps score, (4) relative RULA steps score occurrence, and (5) relative angle distribution. With increasing complexity, the number of variables times (the number of resolvable units per variable) increased. In our example, only significant differences between the treatment concepts were observed at levels that are more complex: the relative RULA step score occurrence and the relative angle distribution (level 4 + 5). With the presented approach, an objective and detailed ergonomic analysis is possible. The data-driven approach adds significant additional context to the RULA score evaluation. The presented method captures data, evaluates the full task cycle, and allows different levels of analysis. These points are a clear benefit to a standard, manual assessment of one main body position during a working task.

Development of a novel histological and histomorphometric evaluation protocol for a standardized description of the mid-palatal suture - An ex vivo study.

The hard palate and mid-palatal suture are highly important for orthodontic treatment. In cases of transverse maxillary deficiency, palatal expansion is the treatment of choice. As nowadays a growing number of adult patients receive orthodontic treatment, an understanding of suture development throughout life is important to derive tailored orthodontic treatment techniques for each age group. Histological, histochemical and immunohistochemical stains (haematoxylin & eosin, Azan, Movat pentachrome, Masson-Goldner trichrome, Sirius Red, CD 31, osteopontin and TRAP) and histomorphometric analyses were re-established to detect the structural conditions of the mid-palatal suture in human cadavers of three different age groups (20-39, 40-59 and 60-80 years). The mid-palatal suture of the selected age groups (total of n = 12; n = 4 in every group m = f) exhibited marked differences in sutural morphology and metabolism. A wide, interdigitated and well-vascularized suture was observed in younger specimens compared with straighter and smaller sutures with fewer vessels and lower bone density in the 60-80 year group. The fibre composition within the sutural gap differed between the three age groups. Delicate fibres were found in the 20-39 year group, and a tightly interwoven 3D fibre-network was observed in the 40-59 year group. Atrophy primarily characterized the fibres in the 60-80 year group. This evidence demonstrates differences between the evaluated groups. These results suggest that the staining methods used are suitable for the description and evaluation of the morphology and metabolism of mid-palatal sutures. Further investigation is necessary to provide an in-depth description of sutural maturation over a lifetime.

Comparative assessment of plaque removal and motivation between a manual toothbrush and an interactive power toothbrush in adolescents with fixed orthodontic appliances: A single-center, examiner-blind randomized controlled trial.

INTRODUCTION: The objective of this 2-arm parallel trial was to determine the plaque removal efficacy (main outcome) and the motivation assessment (secondary outcome) comparing a manual versus an interactive power toothbrush in orthodontic patients. METHODS: Sixty adolescents with fixed orthodontic appliances in both arches were randomized in a 1:1 ratio in this parallel, randomized, examiner-blind controlled clinical trial. Eligibility criteria included at least 16 natural teeth, 1-6 "focus care areas," plaque score of ≥1.75, no severe caries, gingivitis and periodontitis, no dental prophylaxis, no smoking, no antibiotics, and no chlorhexidine mouth rinse. Subjects were to brush unsupervised with either an interactive power toothbrush (Oral-B Professional Care 6000, D36/EB20) with Bluetooth technology or a regular manual toothbrush (Oral-B Indicator 35 soft). Focus care areas were each brushed for 10 additional seconds. Plaque removal was assessed with the use of the Turesky Modification of the Quigley-Hein Plaque Index (TMQHPI) to determine change from baseline at 2 and 6 weeks. Supervised brushing at screening and post-treatment visits recorded actual brushing times. Subject-reported motivational aspects were recorded at screening and week 6. RESULTS: Fifty-nine subjects aged 13-17 years completed the study. The interactive power toothbrush provided significantly (P <0.001) greater plaque reduction versus the manual toothbrush at 2 and 6 weeks according to the whole-mouth TMQHPI. The treatment difference in adjusted mean plaque change from baseline was 0.777 (95% CI 0.614-0.940) at week 2 and 0.834 (0.686-0.981) at week 6. Mean reductions in the number of focus care areas were also significantly greater (P <0.001) in the power brush group at weeks 2 and 6. Brushing times increased significantly at weeks 2 and 6 (P ≤0.013) versus baseline in the interactive power brush group only. Subject-reported motivation was significantly increased in the interactive power brush group at week 6 versus screening (P ≤0.005). CONCLUSIONS: An interactive power toothbrush generated increased brushing times and significantly greater plaque removal versus a manual brush.

A comparative assessment of plaque removal and toothbrushing compliance between a manual and an interactive power toothbrush among adolescents: a single-center, single-blind randomized controlled trial.

BACKGROUND: Many adolescents have poor plaque control and sub-optimal toothbrushing behavior. Therefore, we compared the efficacy of an interactive power toothbrush (IPT) to a manual toothbrush (MT) for reducing dental plaque and improving toothbrushing compliance. METHODS: In this randomized, parallel single-blind clinical study, adolescents brushed twice daily with either a MT (Oral-B® Indicator soft manual toothbrush) or an IPT (Oral-B® ProfessionalCare 6000 with Bluetooth). Subjects brushed for 2 min, plus an additional 10 s for each 'Focus Care Area'. At screening and Week 2, afternoon pre-brushing plaque was assessed via the Turesky Modification of the Quigley-Hein Plaque Index (TMQHPI), and supervised brushing duration was measured. RESULTS: Sixty subjects were randomized; 98% completed. At Week 2, the mean reduction in whole mouth plaque relative to baseline was 34% (p < 0.001) for the IPT versus 1.7% (p = 0.231) for the MT. For Focus Care Areas, the IPT yielded a 38.1% mean TMQHPI reduction (p < 0.001) versus 6.2% for the MT (p < 0.001). Mean brushing time versus baseline increased 34 s in the IPT group (p < 0.001) while remaining flat in the MT group (p = 1.0). CONCLUSIONS: Over 2 weeks, adolescents using an IPT experienced superior plaque reduction and increased overall brushing time versus those using a MT. TRIAL REGISTRATION: This trial was retrospectively registered ( ISRCTN10112852 ) on the 18th, June 2018.

Is there a Genotoxic Potential of Endodontic Root Materials?

BACKGROUND: Leakage of components from endodontic materials (EM) can occur in case of apical extrusion into the periapical tissue. Therefore, an important prerequisite, besides the mechanical properties of the EM, is a high biocompatibility. In the present study, we elucidated the genotoxic potential of EMs of different base composition by utilizing the -H2AX assay. METHODS: For investigation of the genotoxic potential of EM, supernatants of commercially available EM were prepared and dilutions were applied to human gingival fibroblasts. Non-toxic doses of EM were determined by cell viability assay. For the -H2AX assay, human gingival fibroblasts were incubated with predefined concentrations of the supernatants, which were found not to reduce cell viability. Hydrogen peroxide was utilized as positive control. Cells were fixed 1, 6 and 24 hours after addition of the supernatant to the medium, followed by immunostaining for -H2AX. For scoring of -H2AX foci, automated foci counting was performed in at least 80 cells per experiment and time point. The experiments were repeated at least twice. RESULTS: In contrast to hydrogen peroxide treated cells, no elevated -H2AX levels were detected in cells incubated with the EM supernatants. CONCLUSIONS: Samples treated with EM supernatants showed no elevated levels of -H2AX foci, e.g., no genotoxicity. Therefore, all types of EM seem to meet the standard to be called a biocompatible dental material in terms of genotoxicity, and, therefore, the application seems safe.

Constrained posture in dentistry - a kinematic analysis of dentists.

BACKGROUND: How a dentist works, such as the patterns of movements performed daily, is also largely affected by the workstation Dental tasks are often executed in awkward body positions, thereby causing a very high degree of strain on the corresponding muscles. The objective of this study is to detect those dental tasks, during which awkward postures occur most frequently. The isolated analysis of static postures will examine the duration for which these postures are maintained during the corresponding dental, respectively non-dental, activities. METHODS: 21 (11f/10 m) dentists (age: 40.1 ± 10.4 years) participated in this study. An average dental workday was collected for every subject. To collect kinematic data of all activities, the CUELA system was used. Parallel to the kinematic examination, a detailed computer-based task analysis was conducted. Afterwards, both data sets were synchronized based on the chronological order of the postures assumed in the trunk and the head region. All tasks performed were assigned to the categories "treatment" (I), "office" (II) and "other activities" (III). The angle values of each body region (evaluation parameter) were examined and assessed corresponding to ergonomic standards. Moreover, this study placed a particular focus on static positions, which are held statically for 4 s and longer. RESULTS: For "treatment" (I), the entire head and trunk area is anteriorly tilted while the back is twisted to the right, in (II) and (III) the back is anteriorly tilted and twisted to the right (non-neutral position). Static positions in (I) last for 4-10s, static postures (approx. 60%) can be observed while in (II) and (III) in the back area static positions for more than 30 s are most common. Moreover, in (II) the back is twisted to the right for more than 60 s in 26.8%. CONCLUSION: Awkward positions are a major part of a dentists' work. This mainly pertains to static positions of the trunk and head in contrast to "office work." These insights facilitate the quantitative description of the dentist profession with regard to the related physical load along with the health hazards to the musculoskeletal system. Moreover, the results allow for a selective extraction of the most unfavorable static body positions that dentists assume for each of the activities performed.

Restricted posture in dentistry - a kinematic analysis of orthodontists.

BACKGROUND: This study aims at identifying orthodontic activities with the highest frequency of unfavorable/awkward and static postures held over a period of more than 4 s based on kinematic analysis. Moreover, a separate analysis of static postures for orthodontic and non-orthodontic activities serves to evaluate the duration for which these particular postures are assumed. METHODS: In total, 21 (13f/8 m) orthodontists (age: 31.5 ± 3.8 years) participated in this study. CUELA, a personal measurement system, was used to collect kinematic data for all orthodontic activities in a working day. Angle values of the head and torso were evaluated in accordance with ergonomic standards. Only those postures that were held statically for 4 s and longer were selected for further analysis. Alongside the kinematic analysis, the activities performed on-site were also subject to a detailed computerized analysis. The synchronization of data collected from both measurements arranges the patterns of posture found chronologically and in conjunction with the orthodontic activities performed ((I) "treatment" (II) "office" and (III) "other activities"). RESULTS: For (I) we observed an anterior inclination of the head and torso area as well as a twist of the head and neck area to the right. We found anterior back inclination and lateral back torsion to the right for (II) and (III). If, furthermore, we differentiate the duration of static postures, there are primarily short to medium-term (4-30s) static postures identified for (I). Also, categories (II) and (III) predominantly demonstrate static back postures with a duration of up to 30 s. With regard to (II) we observed that the back is ventrally inclined for 10.1% of the total activity duration. CONCLUSIONS: During treatment static strains are observed in the entire head and torso area. On the contrary, static postures prevalent in the torso area are essential for activities of the other categories, particularly office work. These findings allow for a careful selection of unfavorable and static postures for each of the activities performed and help to develop specific preventive measures.

Kinematic analysis of work-related musculoskeletal loading of trunk among dentists in Germany.

BACKGROUND: In Germany, about 86.7 % of the dentists have stated to suffer from pain in the neck and shoulder region. These findings are predominantly based on surveys. Therefore the objective of this study is to conduct a kinematic analysis of occupational posture in dentistry. METHODS: Twenty one dentists (11 f/10 m; age: 40.1 ± 10.4 years) have participated in this examination. The CUELA-System was used to collect kinematic data of the activities on an average dental workday. A detailed, computer-based task analysis took place parallel to the kinematic examination. Through the synchronization of data collected from both measurements, patterns of posture were arranged chronologically and in conjunction with the tasks performed: (I) "treatment" (II) "office" and (III) "other activities". For the data analysis, characteristic data of joint angular distributions (percentiles P05, P25, P50, P75 and P95) of head, neck and torso at pre-defined tasks were examined and assessed corresponding to ergonomic standards. RESULTS: Forty one percent of tasks executed on an average dental workday can be categorized as the treatment of patients. These tasked are most frequently performed in "straight back" positions (78.7 %), whereas 20.1 % were carried out in a "twisted or inclined" torso posture, 1.1 % "bowed" and only 0.1 % "bowed and twisted/inclined to the side" upper body position. In particular, it can be observed that in the area of the cervical and thoracic spine the 75th and 95th percentile show worse angular values during treatment than during non-dental tasks. For the period of treatment (at a standardized dental chair construction), a seated position with a strong inclination of the thoracic spine to the right while the lumbar spine is inclined towards the left is adopted. CONCLUSION: The kinematic analysis of dentists illustrates typical patterns of postures during tasks that are essential to the dental treatment of patients. The postures in the area of the cervical and thoracic spine have higher angular values during treatment compared to other dental tasks. Consistently, appropriate ergonomic design measures to optimize the dental chair and equipment as well as integrated training in ergonomics as part of the study of dentistry to prevent musculoskeletal are recommended.

Psychosocial impact of dental aesthetics in adolescence: validity and reliability of a questionnaire across age-groups.

BACKGROUND: Dental malocclusion is a highly prevalent health condition in adolescence. Patients seek treatment primarily for aesthetic reasons. Therapy benefits are regarded, in the first place, to be psychosocial in nature. Therefore, it is mandatory to consider the perspective of the patient in treatment planning and control using a dental-aesthetics-related quality of life measure. The objective of this study was to investigate whether the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) developed in adult samples including the subscales Dental Self-Confidence, Social Impact, Psychological Impact and Aesthetic Concern is also applicable in adolescents aged 11 years and above. The psychometric properties were examined across three age-groups (11-12, 13-14, 15-17 year olds) with respect to factorial invariance, internal consistency, temporal stability, discriminant validity and gender- or age-associated scale mean differences and item response bias. METHOD: Participants were 1,112 adolescents recruited from 4 institutions: orthodontic and dental practices, schools, and youth clubs. They answered the 23 partially reformulated items of the PIDAQ. Subjective and dentist evaluations of dental occlusion were assessed using the Perception of Occlusion Scale and the Aesthetic Component of the Index of Orthodontic Treatment Need. Both indices were aggregated to one Malocclusion Index (MI-S and MI-D). RESULTS: The fit indices using confirmatory factor analyses suggested that the factor structure and factor loadings underlying the PIDAQ items were invariant across ages (comparative fit index = 0.91, root-mean-square error of approximation = 0.04). Internal consistency and temporal stability were adequate within the age-groupings (Alpha = 0.71-0.88; intra-class correlations = 0.82-0.96). Adolescents with severe compared to slight malocclusion according to both self-evaluation and dentist evaluation were found to differ in all PIDAQ subscales at a level of p < 0.001 for all ages. PIDAQ scale scores were not related to age and gender. On the item level, no evidence for gender or age bias has been found. CONCLUSION: The PIDAQ demonstrates to have good psychometric properties in adolescents, independent of their age. The instrument can be applied in making clinical decisions and in the assessment of psychosocial outcomes of orthodontic therapy.

Brush head composition, wear profile, and cleaning efficacy: an assessment of three electric brush heads using in vitro methods.

OBJECTIVE: The objective of this research was to evaluate a current store brand (SB) brush head for composition/physical characteristics, Wear Index (WI), and cleaning efficacy versus the previous SB brush head refill design (SB control) and the Oral-B Precision Clean brush head (positive control, PC). METHODS: This research consisted of three parts: 1) Analytical analysis using Fourier Transform Infrared (FT-IR) spectrometry to evaluate the chemical composition of the current SB brush head bristles relative to the SB control. In addition, physical parameters such as bristle count and diameter were determined. 2) Wear Index (WI) investigation to determine the Wear Index scores of in vitro-aged brush heads at four weeks (one month) and 13 weeks (three months) by a trained investigator. To "age" the brush heads, a robot system was used as a new alternative in vitro method to simulate aging by consumer use. 3) Robot testing to determine the cleaning performance of in vitro-aged brush heads, comparing one month-aged current SB brush heads with the SB control (one and three months-aged) and the PC brush heads (three months-aged) in a standardized fashion. RESULTS: 1) FT-IR analysis revealed that the chemical composition of the current and control SB refill brush heads is identical. In terms of physical parameters, the current SB brush head has 12% more bristles and a slightly oval brush head compared to the round brush head of the SB control. 2) Wear Index analysis showed there was no difference in the one month-aged current SB brush head versus the one month-aged SB control (1.67 vs. 1.50, p = 0.65) or versus the three months-aged PC brush head (1.67 vs. 1.50, p = 0.65). The one month-aged current SB brush head demonstrated statistically significantly less wear than the three months-aged SB control (1.67 vs. 2.67, p = 0.01). 3) Analysis of cleaning efficacy shows that the one month-aged current SB brush head had improved cleaning performance over the one month-aged SB control brush head (p < 0.05), despite no statistically significant difference in wear. Both the one month-aged current and control SB brush heads showed statistically significantly lower cleaning performance compared to the three months-aged PC brush heads (p < 0.01). CONCLUSION: While the current SB brush head showed improved cleaning over the SB control, it demonstrated significantly lower durability and cleaning in comparison to the PC brush head. Dental professionals should be aware of these differences, both in durability and in cleaning performance, when recommending brush heads to their patients.