Search

Introduction: This aim of this paper is to describe and identify the practitioner and patient characteristics that are associated with treatment recommendations for adult anterior open bite patients across the United States., Methods: Practitioners and patients were recruited within the framework of the National Dental Practice-Based Research Network. Practitioners were asked about their demographic characteristics and their treatment recommendations for these patients. The practitioners also reported on their patients' dentofacial characteristics and provided initial cephalometric scans and intraoral photographs. Patients were asked about their demographic characteristics, previous orthodontic treatment, and goals for treatment. Four main treatment groups were evaluated: aligners, fixed appliances, temporary anchorage devices (TADs), and orthognathic surgery. Extractions were also investigated. Predictive multivariable models were created comparing various categories of treatment as well as extraction/nonextraction decisions., Results: Ninety-one practitioners (mostly orthodontists) and 347 patients were recruited from October 2015 to December 2016. Increased aligner recommendations were associated with white and Asian patients, the presence of tongue habits, and female practitioners. TADs were recommended more often in academic settings. Recommendations for orthognathic surgery were associated with demographic factors, such as availability of insurance coverage and practitioner race/ethnicity, and dentofacial characteristics, such as anteroposterior discrepancies, more severe open bites, and steeper mandibular plane angles. Extraction recommendations were largely associated with severe crowding and incisor proclination., Conclusions: Both doctor and patient demographic factors, as well as dentofacial characteristics, were significantly associated with treatment recommendations for adult anterior open bite patients., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Background: Pacifier sucking habit has been associated in the literature with alterations of dental occlusion, and it could be a predisposing factor for other poor oral habits among children. Orthodontic pacifiers have been introduced in the market aiming to reduce these disadvantages caused by the conventional type of pacifiers. The aim of this study was to evaluate the prevalence of poor oral habits and malocclusions, after usage of orthodontic pacifiers in children with primary dentition., Methods: A sample of 198 pre-school children, aged 3-5 years, (96 males and 102 females) who had exclusively used an orthodontic pacifier were included in order to assess the level of poor oral habits and the absence/presence of dental malocclusion. Firstly, children's parents/legal guardians were given a validated questionnaire, then the children were clinically examined at a dental clinic., Results: Most of the children (79.79%) had started using the orthodontic pacifier within the first 3 months of life, and the 43.49% of them continued using it over a period of 2 years. The recorded percentage for those who had used it throughout sleep was 89.39%. Mouth breathing during the night was reported for 36.04% of the children. Tongue thrust swallow affected 16.16% of the sample. The 5.56% of the data indicated the presence of fingersucking/thumbsucking habit. The noted percentages for children with lip biting, lingual interposition between teeth at rest and those with nail biting, were 5.56, 12.63 and 15.15%, respectively. The regression revealed a significant contribution between early start of using an orthodontic pacifier with the prevalence of fingersucking/thumbsucking (OR 0.13, 95% CI 0.04-0.47, p = 0.0004). This also reported a noticeable increase of the malocclusion prevalence among the female gender (OR 2.74, 95% CI 1.42-5.31), as well as those who were not exclusively breastfed (OR 2.26, 95% CI 1.17-4.37)., Conclusions: Orthodontic pacifiers does not favor the development of poor oral habits, even if it has been used for a period of 2 years in children with primary dentition. Children who begin to use orthodontic pacifier between 0 and 3 months, are less likely to acquire fingersucking/thumbsucking habit. The use of an orthodontic pacifier appears not to be correlated with the prevalence of malocclusion in primary dentition, differently from what stated in literature about the conventional type of pacifier.

Study Objectives: To evaluate the prevalence of probable sleep bruxism (SB) and its association with sleep features, orthodontic fixed appliance wearing, and extraoral and intraoral clinical signs and symptoms in a population of adolescents., Methods: Two hundred thirty-nine 12-year-old adolescents enrolled in private and public schools in Brumadinho, southeast Brazil, and their parents were invited to participate. They answered a questionnaire containing information regarding adolescents' sleep features and history of SB. Extraoral and intraoral examination was performed to identify some clinical signs (ie, absence of lip competence, presence of mouth breathing, clicks in the temporomandibular joint [TMJ], tooth wear) and symptoms (ie, pain in the masseter muscle upon palpation), and ongoing orthodontic treatment with fixed appliances. Parental report and clinical examination were used to determine probable SB. Descriptive statistics and logistic regression were performed to identify association of probable SB with independent variables., Results: Of 239 adolescents initially selected, 231 (96.6%) participated in the study. Prevalence of probable SB was 16.9%. Adolescents who snored during sleep (odds ratio [OR] = 3.14; 95% confidence interval [CI] = 1.47-6.70), adolescents who did not have clicks in the TMJ (OR = 3.37; 95% CI = 1.11-10.15), and those who wore orthodontic appliances (OR = 2.72; 95% CI = 1.04-7.14) were more likely to be in the group with probable SB., Conclusions: Snoring, absence of clicks in the TMJ, and fixed appliance wearing were associated with probable SB among adolescents. This study adds to the ongoing research on SB in adolescents and its associated factors., Commentary: A commentary on this article appears in this issue on page 1281., (© 2018 American Academy of Sleep Medicine.)

Purpose: To assess the impact of fixed appliance therapy on the quality of life of a cohort of Brazilian adolescents., Methods: The treatment group was composed of individuals who started orthodontic treatment. The control group was composed of individuals not selected for immediate treatment. Adolescents answered the Brazilian short form of the Child Perceptions Questionnaire (CPQ 11-14 ). Higher scores indicate a greater negative impact on quality of life. Adolescents in the treatment group completed four sets of interviews: prior to appliances' bonding (T1), 1 month (T2), 6 months (T3) and 12 months (T4) after appliances' placement. Adolescents in the control group were assigned to a comparable schedule. Statistics included inter-group comparisons, Friedman and Wilcoxon tests, and mixed-effects models., Results: In the treatment group, the functional limitation score was higher at T1 (p = 0.004) and T2 (p = 0.007) compared to T4. The emotional well-being score was higher at T1 compared to T2 (p < 0.001), T3 (p < 0.001) and T4 (p < 0.001). The overall CPQ 11-14 score was higher at T1 compared to T2 (p = 0.005), T3 (p < 0.001) and T4 (p < 0.001). The overall CPQ 11-14 score was also higher at T2 compared to T3 (p = 0.001). No significant change was found in the control group. In the mixed-effects models, the interaction between group (treatment) and time was significant for functional limitations (p < 0.001), emotional well-being (p < 0.001), social well-being (p = 0.004) and the overall CPQ 11-14 score (p < 0.001)., Conclusion: Quality of life improved among adolescents undergoing orthodontic treatment. Orthodontists should inform patients what they might expect regarding the physical and the psychosocial repercussions of appliance therapy.

Background: At present, many scholars have studied the periodontal health status of patients undergoing orthodontic treatment with fixed appliances and invisalign. However, those results are inconsistent. Therefore, we conducted this meta-analysis, and then provide reference for clinical treatment., Methods: Most databases, such as the Cochrane Library, EMBASE, PubMed, Medline, Chinese Biomedical Literature Database, CNKI, and Wan Fang Data were retrieved for related articles from the establishment of the database to October 2017. Meanwhile, we also searched the references of the related literatures manually, in order to increase the included literatures. Two researchers screened the related literatures according to the inclusion criteria and exclusion criteria. Stata 12.0 software was used for data analysis, and results are estimated by odds ratio (OR) and 95% confidence interval (CI)., Results: Finally, 7 articles, including 368 patients, were included into our meta-analysis. Meta-analysis results showed that there was no statistically significant difference of gingival index (GI) and sulcus probing depth (SPD) status between the invisalign group and the control group, including at 1, 3, and 6 months (all P > .05). When compared with the control group, the invisalign group presented a lower plaque index (PLI) and sulcus bleeding index (SBI) status at 1 month (OR = -0.53, 95% CI: -0.89 to -0.18; OR = -0.44, 95% CI: -0.70 to -0.19, respectively), 3 months (OR = -0.69, 95% CI: -1.12 to -0.27; OR = -0.49, 95% CI: -0.93 to -0.05, respectively), and 6 months (OR = -0.91, 95% CI: -1.47 to -0.35; OR = -0.40, 95% CI: -0.63 to -0.07, respectively). Subgroup analysis showed that the SPD status was lower in the invisalign group at 6 months when measured the teeth using Ramfjord index (OR = -0.74, 95% CI: -1.35 to -0.12). However, there was no statistically significant difference between the 2 groups when using other measure methods (OR = 0.12, 95% CI: -0.26 to 0.17)., Conclusion: Our meta-analysis suggests that comparing with the traditional fixed appliances, patients treated with invisalign have a better periodontal health. However, more studies are needed to confirm this conclusion in the future.

Keratocystic odontogenic tumour (KCOT) is considered one of the most aggressive odontogenic lesions presenting high recurrence rate which varies according to treatment modalities employed for management. The treatment rendered should have a lowest possible risk of recurrence and least morbidity while still eradicating the lesion. Although the radical treatment options like enucleation and en bloc resection are associated with lesser recurrences, these can lead to greater morbidity, especially in children with developing teeth and jaw bones, thus, emphasising need to consider more conservative treatment options like decompression and marsupialisation. The purpose of this article was to report the case of an 11-year-old male child with KCOT in the mandibular region associated with impacted premolar treated successfully with decompression and intraoral appliance. After 24 months of follow-up, the spontaneous eruption of premolar was noted with complete resolution of periapical radiolucency. No recurrence was noted even after 5-year follow-up., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background: The role of marketing and industry in the treatment decisions of orthodontists has received increasing attention in recent years with clinical research typically undertaken subsequent to established use of these devices and often failing to confirm the promise of manufacturers' claims. This meta-epidemiological study was undertaken to assess the proportion of clinical trials in orthodontics evaluating commercially marketed products and to evaluate the direction of the results of these studies., Methods: Electronic searching was undertaken to identify randomized controlled trials (RCTs) published over a 5-year period (1 January 2012 to 31 December 2016). Data obtained included the type of marketed intervention, direction of effect and declaration of both industry sponsorship and conflict of interest., Results: Eighty-four RCTs published in 23 scientific journals were included with the highest percentage in the American Journal of Dentofacial Orthopedics (AJO-DO) (23.8%), followed by the European Journal of Orthodontics (EJO) (14.3%), Journal of Orthodontics (JO) (10.7%) and Angle Orthodontist (AO) (10.7%). Overall, 45% (38/84) of clinical trials assessed involved analysis of marketed products after their introduction. Interventions to improve oral health or circumvent the risk of iatrogenic damage, such as white spot lesions, were most commonly assessed (15.8%), with the relative merits of non-surgical adjuncts (14.1%) and other orthodontic auxiliaries (13.1%) also frequently evaluated. In 44% of RCTs, a positive effect of the marketed intervention was not reported. Industry sponsorship of the research was declared in 9.5% RCTs. No significant associations between the direction of the effect and both declaration of industry sponsorship (p = 0.56) and conflict of interest (p = 0.96) were detected. Moreover, for marketed and non-marketed products, no significant associations for both declaration of industry sponsorship (p = 0.44) and conflict of interest (p = 0.28) were found., Conclusions: Almost half of orthodontic clinical trials over the past 5 years involve analysis of marketed products after their introduction. The results highlight a potential source of waste in orthodontic research emanating from existing approaches to licensing and marketing of orthodontic products.

Objective: The main purpose of the present systematic review was to evaluate the quantitative effects of the pendulum appliance and modified pendulum appliances for maxillary molar distalization in Class II malocclusion., Materials and Methods: Our systematic search included MEDLINE, EMBASE, CINAHL, PsychINFO, Scopus and key journals and review articles; the date of the last search was 30 January 2017. We graded the methodological quality of the studies by means of the Quality Assessment Tool for Quantitative Studies, developed for the Effective Public Health Practice Project (EPHPP)., Results: In total, 203 studies were identified for screening, and 25 studies were eligible. The quality assessment rated four (16%) of the study as being of strong quality and 21 (84%) of these studies as being of moderate quality. The pendulum appliances showed mean molar distalization of 2-6.4 mm, distal tipping of molars from 6.67° to 14.50° and anchorage loss with mean premolar and incisor mesial movement of 1.63-3.6 mm and 0.9-6.5 mm, respectively. The bone anchored pendulum appliances (BAPAs) showed mean molar distalization of 4.8-6.4 mm, distal tipping of molars from 9° to 11.3° and mean premolar distalization of 2.7-5.4 mm., Conclusions: Pendulum and modified pendulum appliances are effective in molar distalization. Pendulum appliance with K-loop modification, implant supported pendulum appliance and BAPA significantly reduced anchorage loss of the anterior teeth and distal tipping of the molar teeth.

Social media offers an accessible resource for gaining valuable insights into the social culture of bullying. The purpose of this study was to qualitatively analyse Twitter posts for common themes relating to dentofacial features, braces and bullying. Twitter's database was searched from 2010 to 2014 using keywords relevant to bullying, teeth and orthodontics. Two investigators assessed the Twitter posts, and selected those that conveyed the experiences or opinions of bullying victims. The posts were qualitatively analysed using thematic analysis. Of the 548 posts screened, 321 were included in the final sample. Four primary categories relating to 'dental-related bullying' were identified: (i) morphological features, (ii) psychological and psychosocial impact, (iii) coping mechanisms and (iv) the role of family. Bullied individuals reported a diverse range of psychological impacts and coping mechanisms. Secondary categories were also identified. Family members, for example, were found to play both a contributory and mediatory role in bullying. In summary, social media can provide new and valuable information about the causal factors and social issues associated with oral health-related bullying. Importantly, some coping mechanisms may mitigate the negative effects of bullying., (© 2017 John Wiley & Sons Ltd.)

Background: Infants with Robin sequence (RS) suffer from upper airway obstruction (UAO) and feeding problems. We developed an oral appliance with a velar extension in combination with functional treatment and appropriate feeding techniques, which was proven effective in isolated RS. As the above problems are particularly challenging in syndromic RS, we set out to evaluate our treatment concept also in these patients., Methods: We searched our electronic departmental database to identify all children admitted to our department between 01/01/2003 and 31/12/2009 because of syndromic RS. UAO was quantified by cardiorespiratory sleep studies performed before and during treatment with a modified palatal plate. This appliance consists of a palatal part, covering the hard palate as well as the alveolar ridges and the potential cleft, and a velar extension shifting the tongue in a more anterior position, thereby opening the pharyngeal airway. It is adjusted by fiberoptic nasopharyngoscopy and controlled by cardiorespiratory sleep studies. Obstructive sleep apnea was defined as a mixed obstructive sleep apnea index (MOAI) >3/h. Feeding modalities before and after treatment and weight gain, determined as standard deviation score, were also evaluated., Results: Of 68 children meeting inclusion criteria, 56 completed treatment (46 of these being infants). Underlying diagnoses included craniofacial dysostosis (N = 13) and synostosis syndromes (N = 5), unspecified dysmorphic syndromes (N = 23) and miscellaneous rare conditions (N = 27). Median MOAI decreased from 8.5 (range 0.3-76.0) at admission to 1.1 (0.0-5.2) at discharge (p < 0.001). 51 children received only a TPP and 5 additionally continuous positive airway pressure (CPAP) or high-flow nasal cannula during sleep for mild residual OSA. Three children ultimately required tracheostomy. The number of exclusively gavage fed infants was reduced from 23 to 7. Conversely, the number of children fed exclusively by mouth increased from 18 to 30. Median SDS for weight decreased from -1.6 (-3.5-1.7) to -1.3 (-4.1-2.5). Twelve children had their treatment prematurely discontinued, e.g. due to laryngeal collapse/laryngomalacia. No patient died during treatment., Conclusion: Treatment of UAO and feeding problems in these children with syndromic RS by a modified palatal plate with a velar extension was shown to be effective and safe. If confirmed in prospective studies, it may help to avoid more invasive interventions.

The purpose of this retrospective cohort study was to measure the salivary levels of nickel (Ni), chromium (Cr), iron (Fe) and copper (Cu) released from metal and esthetic fixed orthodontic appliances. Ninety patients were divided into three groups (n=30): control (those who had never undergone orthodontic treatment), metal appliance (stainless steel brackets and bands, and nitinol archwires) and esthetic appliance (polycarbonate brackets and tubes, and rhodium-coated nitinol archwires). Patients undergoing orthodontic treatment had used their appliances for periods between one and six months. Ni, Cr, Fe and Cu salivary concentrations were measured by the Total Reflection X-Ray Fluorescence technique. Kruskal-Wallis and Bonferroni-Dunn test showed that Ni (p=0.027) and Cr (p=0.040) concentrations were significantly higher for patients undergoing metallic orthodontic treatment than for the esthetic group. No significant difference regarding Ni and Cr (p=0.447) concentrations were observed between the metal and the control groups (p=0.464 and p=0.447, respectively) or between the esthetic and the control groups (p=0.698 and p=0.912, respectively). Ni and Cr concentrations were significantly influenced by the type of appliance used. Fe and Cu concentrations were not affected by the type or use of orthodontic appliances., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

The aim of this study was to evaluate the change in mandibular position during a two-phase orthodontic treatment of skeletal Class II malocclusion. Thirty consecutively treated Chinese male adolescents who had undergone two-phase treatment with Herbst appliance and fixed appliance and fulfilled the specific selection criteria were sampled. Cephalograms taken at T0 (before treatment), T1 (at the end of functional appliance treatment), and T2 (at the end of fixed appliance treatment) were analyzed. The change in sagittal positioning of the mandible was 6.8 ± 3.44 mm in phase I (T0-T1), 0.4 ± 2.79 mm in phase II (T1-T2), and 7.2 ± 4.61 mm in total. The mandible came forward in 100% of the patients at T1. In phase II, it came forward in one-third (positive group) remained unchanged in one-third (stable group) and went backward in one-third (negative group) of the patients. At T2, it came forward twice as much in the positive group compared to the negative group. Mandibular length was significantly increased in 100% of the patients in both phases. In conclusion, during the treatment with functional appliance, the mandibular prognathism increases in all patients, whereas during the treatment with fixed appliance there is no significant change in mandibular prognathism.

Introduction: The choice of brackets, bands and wires is a very important aspect of orthodontic treatment. Stainless steel prevailed for a long time, but new alloys and resources have emerged to diversify the orthodontic wire mechanics., Objective: This study aimed to investigate the profile and materials used by orthodontists practicing in the State of São Paulo, Brazil., Methods: A questionnaire was sent to 2,414 specialists in Orthodontics and Dentofacial Orthopedics registered with the Regional Board of Dentistry of São Paulo State (CRO-SP). To assess the association between qualitative variables, the Chi-square association test was employed at 5% significance level., Results: Five hundred and ninety-three (24.65%) questionnaires were completed and sent back. Efficiency was the key reason given by the professionals for choosing a particular material. The majority showed a preference for metal brackets (98%), followed by ceramics (32%) and polycarbonate (7.8%). The most widely used brackets had 0.022 x 0.028-in slots (73.2%). Regarding orthodontic wires, 88.2% employed round steel wires and conventional round NiTi wires, while 52.6% used round heat-activated NiTi and 46.5% rectangular TMA wires. Elastics (92.9%) were the most widely used method to tie the orthodontic archwire to the bracket., Conclusions: In this survey, the orthodontists claimed that efficiency was the major motivator for choosing orthodontic materials. Conventional brackets tied with conventional elastic ligatures are still the most used by the professionals. Among steel and conventional Nitinol wires, round wires ranked first. The use of resources recently available to Brazilian orthodontists, such as self-ligating brackets and mini-implants, was not significant.

Background: Studies have shown conflicting results on the association between nickel exposure from orthodontic appliances and nickel sensitization. OBJECTIVES & METHOD: In a cross-sectional study, we investigated the association between nickel sensitization and exposure to orthodontic appliances and piercings. 4376 adolescents were patch tested following a questionnaire asking for earlier piercing and orthodontic treatment. Exposure to orthodontic appliances was verified in dental records., Results: Questionnaire data demonstrated a reduced risk of nickel sensitization when orthodontic treatment preceded piercing (OR 0.46; CI 0.27-0.78). Data from dental records demonstrated similar results (OR 0.61, CI 0.36-1.02), but statistical significance was lost when adjusting for background factors. Exposure to full, fixed appliances with NiTi-containing alloys (OR 0.31, CI 0.10-0.98) as well as a pooled 'high nickel-releasing' appliance group (OR 0.56, CI 0.32-0.97) prior to piercing was associated with a significantly reduced risk of nickel sensitization., Conclusion: High nickel-containing orthodontic appliances preceding piercing reduces the risk of nickel sensitization by a factor 1.5-2. The risk reduction is associated with estimated nickel release of the appliance and length of treatment. Sex, age at piercing and number of piercings are also important risk indicators. Research on the role of dental materials in the development of immunological tolerance is needed., (© 2012 John Wiley & Sons A/S.)

The purpose was to define the impact of orthodontic appliances on the density of the underlying dental bone tissue. Radiographic images of teeth were made in 27 study subjects before and twelve months after fixed orthodontic appliances were carried. The radiographs were digitalized and the levels of gray at sites where the greatest bone resorption was expected were transformed into optic density. In the standardization and comparison of values from the first and the second measurements the copper calibration wedge--a stepwedge--was used. Optic densities in the observed sites were compared with optic densities of the calibration wedge and expressed as their thickness equivalent. The study results showed no statistically significant difference in bone densities, indicating that the orthodontic therapy was properly planned and carried out and that excessive forces were not used in the applied correctional procedures.

Objective: To investigate the use of bonded molar tubes (BMTs) by specialist orthodontists., Design: Prospective postal questionnaire., Setting: Ireland., Participants: Registered members of the Orthodontic Society of Ireland., Methods: A questionnaire was posted to registered members of the Orthodontic Society of Ireland. It investigated demographics, pattern of use, reasons for use and techniques for placement of BMTs., Results: A 74% response rate was obtained. In more than 80% of cases, BMTs were used on first and second permanent molars by 52% and 33% of orthodontists respectively. BMT usage was adopted by 97% of respondents in the previous decade. Direct bonding was used by all for BMT placement. Etch times for molars, compared to other teeth, increased from 15 to 30 seconds by 51% of orthodontists. Of the respondents, 97% used light-cured adhesives and 17% used self-etching primers. Molar tube holders were preferred by 54% for placement. Only with a history of epilepsy, were bands preferred to BMTs. BMTs were regarded as more cost-effective than molar bands by 66% of responding clinicians., Conclusions: Specialist orthodontists preferred BMTs to bands on first permenent molars. Direct bonding was favoured using a 30-second etch, a light-cured primer and adhesive with specialized molar tube holders. BMTs were perceived to be more cost-effective than molar bands.

Background: The importance of the nickel exposure from fixed orthodontic appliances is under continuous discussion., Objectives: Our aim was to investigate nickel allergy and the risk of nickel sensitization among female adolescents during orthodontic treatment with fixed appliances as compared with non-treated female adolescents., Subjects and Methods: Female patients starting or with ongoing orthodontic treatment (n = 30) and young females without a history of orthodontic treatment (n = 140) were studied. Patch testing with 5% nickel sulfate was carried out twice on each participant with an approximately 1-year interval. The subjects completed a questionnaire before the first testing., Results: None of the 7 orthodontic patients with a positive patch test reaction to nickel had any clinically visible intraoral allergic symptoms during their treatment. No significant difference was seen in the occurrence of positive nickel reactions in regard to orthodontic treatment, or between the first and second tests. In the treatment group, 2 patients changed from nickel-positive to nickel-negative during the observation period, and one patient showed an opposite change. The quantity and course of changes in the repeated nickel patch test reactions did not differ significantly between the subjects with and without orthodontic treatment experience., Conclusions: Nickel sensitization from orthodontic appliances is improbable, but nickel sensitization may develop also during orthodontic treatment., (© 2011 John Wiley & Sons A/S.)

Objectives: To estimate the number of adults currently being treated by specialist orthodontists in the UK, both within the National Health Service (NHS) and privately, together with the factors relating to adults undergoing orthodontic treatment, their malocclusions and details of treatment undertaken., Design: Self-administered postal questionnaire., Participants and Setting: All individuals entered on the General Dental Council's Specialist List in Orthodontics, registered within the UK., Methods: A questionnaire was sent to all those on the General Dental Council's Specialist List in Orthodontics to ascertain the numbers of adult patients being treated by specialist orthodontists and factors relating to their treatment. This included age and gender of adults being treated, sources of referral, type of orthodontic treatment carried out, disciplines involved in multidisciplinary treatment, appliance types used and issues which practitioners felt affected adult treatment. Adults undergoing orthognathic treatment were excluded from this study., Results: The questionnaire yielded a response rate of 70%. Those respondents working in combined hospital/university posts treated the largest proportion of adults within the NHS and those working in specialist orthodontic practice treated the largest number privately. Within 1 year, the estimated mean number of adult cases started by specialist orthodontists within the NHS was 20.9 and privately was 28.2. The majority of adults treated were reported to be within the 26-35 year age group. Most adult patients were referred for orthodontic treatment by their general dental practitioners and over 70% of treatment provided was orthodontic-only. Adults' concerns regarding the appearance of orthodontic appliances was quoted by orthodontists as being the most commonly occurring potentially complicating factor with regards to both NHS and private treatment., Conclusions: Although there are reports in the literature that the number of adult orthodontic patients is increasing, there are no comprehensive figures regarding the number of adults previously treated within the NHS and privately in the UK to compare our data with. This paper presents initial data relating to practitioners' estimates of the numbers of adults being treated in the UK.

Objective: To report the prevalence and clinical features of angular cheilitis occurring in patients undergoing orthodontic treatment., Design: Cross-sectional, observational study., Setting: Three centres were involved; Glasgow Dental Hospital and two specialist orthodontic practices, one in Scotland and one in Greece., Subjects and Methods: Six hundred and sixty consecutive patients undergoing orthodontic treatment were examined over a 9 month period., Main Outcome Measures: The presence and absence of angular cheilitis was recorded. A six-point clinical scale was used to describe the clinical features of angular cheilitis when present. Chi-squared tests were used to investigate the association between the presence of angular cheilitis and oral hygiene level/appliance type., Results: Eleven per cent of orthodontic patients in this Western European population, showed signs of angular cheilitis. No correlation was found between the presence of angular cheilitis and gender. Good oral hygiene was associated with a reduced prevalence (P<0.01)., Conclusion: Angular cheilitis is a multifactorial condition that can occur in a small percentage of patients during orthodontic treatment. Good oral hygiene may be associated with a reduced risk. A new clinical grade of angular cheilitis is suggested that may help future research. Further studies are required to investigate the microbiological features associated with angular cheilitis occurring in orthodontic patients, as well as associations with medical conditions, such as asthma.

Unlabelled: The present study, which focused on Lithuanian 11-15-year-old schoolchildren, was aimed to describe the frequency of orthodontic anomalies in terms of self-reported complaints about malposed teeth and malocclusion and self-reported use of orthodontic appliances (removable or braces) across different sociodemographic strata., Material and Methods: The study population comprised 5632 schoolchildren surveyed in the 2005-2006 school year according to the WHO collaborative cross-national HBSC study in Lithuania., Results: Almost half (47.5%) of schoolchildren reported orthodontic complaints. Therefore, only 15.8% of total population or 27.0% of schoolchildren who had orthodontic complaints reported wearing orthodontic appliances. Several municipalities of Lithuania with a high prevalence of orthodontic problems among schoolchildren were identified. Orthodontic problems were more prevalent among girls than boys. The prevalence of orthodontic complaints was not associated with social factors, while the use of orthodontic appliances was significantly related to social determinants. Children from rural areas were 2.44 times less likely of wearing orthodontic appliances than those living in cities, and children from families with low affluence were 2.33 times less likely of wearing orthodontic appliances than children from high-affluence families., Conclusion: There is a considerable variation and high social inequalities in need of orthodontic treatment among schoolchildren across different municipalities in Lithuania.

Aims: To evaluate the prevalence of pain associated with temporomandibular disorders (TMD) in obstructive sleep apnea syndrome (OSAS) patients referred for oral appliance therapy., Methods: Eighty-seven patients (46 men and 41 women), between 18 and 65 years of age, with an apnea-hypopnea index (AHI) of > 5 and < 30 (events by sleep hour), and body mass index (BMI) of =or< 30 Kg/m(2) were evaluated according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) to determine the presence of signs and symptoms of TMD. Statistical analyses included correlations assessed by Pearson's test., Results: Fifty-two percent of patients presented symptoms of TMD. Thirty-two patients (average age 47 +/- 11 years, AHI 17.3 +/- 8.7, BMI 25.9 +/- 3.8 kg/m(2)) completed the study. According to the Scoring Protocol for Graded Chronic Pain (Axis II-RDC/TMD), 75% of the patients presented chronic pain related to TMD, categorized as low disability grade I (< 50 points for pain intensity, and < 3 disability points). The most common TMD diagnosis was myofascial pain with and without limited mouth opening and arthralgia (50%)., Conclusion: The high prevalence of TMD in the current study indicates that patients with OSAS referred for oral appliance therapy require specific evaluation related to TMD.

Objective: Phenotypical Down syndrome includes pharyngeal and maxillary hypoplasia and, frequently, constricted maxillary arch with nasal obstruction., Study Design: This clinical trial assessed the effects of rapid maxillary expansion on ENT disorders in 24 children with Down syndrome randomly allocated to receive either rapid maxillary expansion or not. Each group received ENT and speech therapy assessments before expansion and after the device had been removed., Results: In the rapid maxillary expansion group, the yearly ENT infection rate was reduced when assessed after device removal (p < 0.01). The parents of rapid maxillary expansion children reported a reduction in respiratory obstruction symptoms. Audiological assessment revealed improvements in the rapid maxillary expansion group (p < 0.01). Cephalometry showed increased maxillary width in the rapid maxillary expansion group., Conclusions: Rapid maxillary expansion resulted in a reduction in hearing loss, yearly rate of ENT infections and parentally assessed symptoms of upper airway obstruction, compared with no treatment. These findings are probably related to expanded oronasal space, due to rapid maxillary expansion.

Unlabelled: The objective of the present study was to assess the public accessibility of orthodontic care in Lithuania., Material and Methods: In 2008, a request for the information about various aspects of public orthodontic care during 2000-2007 in Lithuania was submitted to the State Patients' Fund at the Ministry of Health. The data on the demographic distribution of orthodontists in Lithuania were received from the Lithuanian Dental Chamber. The authors of the paper also analyzed the national legislation regulating the State Patients' Fund expenditure on orthodontic care and treatment., Results: In 2007, there were 73 orthodontists-practitioners in Lithuania, most of them highly concentrated in major cities and towns: most of them were practicing in Vilnius (22) and Kaunas (20), while there were only 5 orthodontists in Klaipeda, 4 in Siauliai, 3 in each of Panevezys and Marijampole. The public orthodontic treatment is rendered only to patients suffering from most severe pathologies. With the constantly increasing expenditure of the State Patients' Fund, the national public orthodontic care system definitely undergoes significant development: the number of patients who received the treatment with removable and with fixed orthodontic appliances was gradually increasing during 2002-2007, with however, a very small number of new facilities for ambulatory treatment facilities of orthodontists (consultations included). The number of patients who received treatment with removable orthodontic appliances was specifically higher in Siauliai and Telsiai, Panevezys and Utena districts, with fixed orthodontic appliances - in Vilnius and Alytus, Kaunas and Marijampole, Panevezys and Utena regions. The analysis of the availability of public orthodontic treatment showed a marked increase in the number highly-specialized ambulatory facilities in Vilnius and Alytus district in 2002-2007., Conclusions: Specialists providing orthodontic treatment in the country are highly concentrated, while in general public orthodontic treatment undergoes development at the moment. The accessibility of orthodontic treatment in Lithuania, especially in the regions distant from Vilnius and Kaunas, remains inadequate.

The purpose of this study was to evaluate the changes in orthodontic care patterns over a sixteen-year period in a university clinical setting. The average numbers of students, clinical procedures, and orthodontic appliances were examined from the time period 1988-2003. Appliance number and type were evaluated as a function of increased predoctoral and postdoctoral class sizes, student to faculty ratios, and decreased operating budgets for faculty recruitment. For the period 1988-98, the insertion of orthodontic appliances by dental students remained constant. A permanent increase in the predoctoral class size occurred in 1996 without an increase in faculty support, contributing to a decline in appliance insertions by students from 1999 to 2003. This time period also saw major increases in the postdoctoral class size and a reorganization of the clinical facility that then began to require the pairing of dental students to provide comprehensive care, thus decreasing their clinical exposure to the care of children. The overall clinical experience at the predoctoral level in orthodontic procedures declined, which resulted in a change in clinical requirements and new methods to ensure clinical competency.

Background: The use of lingual orthodontic appliances and the training background of orthodontists in Australia using the lingual orthodontic technique are largely unknown. The aim of this study was to investigate the profile of lingual orthodontic users in Australia., Methods: Four hundred and fifty questionnaires consisting of 15 questions were sent out to orthodontists in Australia. We obtained a 62 per cent return rate (278) with a 58 per cent rate of completed questionnaires. Statistical analysis using SPSS was performed and various outputs were obtained., Results: Of the completed returns, 23 per cent were current lingual users; 69 per cent were not and 8 per cent were previous users but have stopped using the appliance. The majority (90 per cent) of the current lingual users were males. The highest percentage of users (35 per cent) was in New South Wales while the smallest percentage was in Tasmania (2 per cent). Around 40 per cent of respondents attended lingual courses as part of their specialist training programme, while 73 per cent had attended lingual courses since graduation and 82 per cent would consider attending a lingual course in the future. Of the 60 per cent current users who did not have a lingual component in their specialist training programme, almost nine-tenths had attended lingual courses since graduation. Of the non-lingual users, 14 per cent attended lingual courses as part of their specialist training programme, 28 per cent attended lingual courses since graduation and 38 per cent would consider attending a lingual course in the future. The main reason cited for being a non-lingual user was that lingual orthodontics could not be an integral part of the practice., Conclusions: Most of the orthodontists who graduated more than 16 years ago from their postgraduate training were non-users of the lingual appliance. It seems that around one in four orthodontists currently use the lingual technique, of which NSW orthodontists make up the largest group. Only one-fifth of users had some lingual component in their formal orthodontic training and about half of them have attended lingual courses after graduation. Almost half of orthodontists in Australia would consider attending a lingual course in the future. This survey provides a sound basis for course co-ordinators to plan for continuing lingual orthodontics in the future.

Objective: To test the hypothesis that a new orthodontic appliance with a velar extension that shifts the tongue anteriorly would reduce upper airway obstruction in infants with Pierre Robin sequence (PRS)., Study Design: Eleven infants with PRS (median age, 3 days) and an apnea index (AI) >3 were studied. The effect of the new appliance on the AI was compared with that of a conventional appliance without a velar extension by using a crossover study design with random allocation., Results: Compared with baseline (mean AI, 13.8), there was a significant decrease in the AI with the new appliance (3.9; P value <.001), but no change with the conventional appliance (14.8; P = .842). Thus, the relative change in AI was -71% (95% CI, -84--49) for the new appliance and +8% (95% CI, -52-142) for the conventional appliance, which was significantly different (P = .004). No severe adverse effects were observed., Conclusion: This new orthodontic appliance appears to be safe and effective in reducing upper airway obstruction in infants with PRS.

Introduction: The purposes of this study were to document orthodontic treatment currently provided by general dentists for comparison with past and future studies and to ascertain variables that influence practitioners' orthodontic treatment patterns., Methods: A 21-item survey was mailed to 750 master's level members of the Academy of General Dentistry. Surveys returned within 8 weeks were included for statistical analysis., Results: The response rate was 62%. Most practitioners spent less than 10% of their practice time providing orthodontic treatment and reported that this would not change in the future. Many provided orthodontic treatment in the permanent dentition, and the most common conditions or malocclusions treated were space maintenance, anterior crossbite, rotation, habits, molar uprighting, and posterior crossbite. The most common orthodontic appliances used were removable Hawley appliances with finger springs, straight wire orthodontic therapy, rapid palatal expanders, and functional appliances., Conclusions: The number of general dentists providing comprehensive orthodontic treatment has not changed since previous surveys; practitioners also do not expect a change in the next 5 years. Factors that influenced the orthodontic treatment provided included the primary source of orthodontic training, the number of orthodontic continuing education hours earned per year, the practitioner's location, and the proximity to the nearest orthodontist.

Objective: Compare 5-year-old dental arch relationships of patients from three centers with differing primary protocols., Design: Retrospective study of treatment outcomes using blinded evaluation of dental study casts., Setting: Three major cleft-craniofacial centers; one (center A) is a free-standing institution, and two (centers B and C) are university hospitals., Patients: 118 (A = 41; B = 33; C = 44) consecutively treated 5-year-old patients with complete, nonsyndromic unilateral cleft lip and palate., Interventions: Centers A and C completed primary repair without presurgical orthopedics by 18 months (center A in three surgeries and center C in two surgeries). Center B used passive presurgical orthopedics with lip/soft palate repair at 6 months and gingivo-alveoloplasty/hard palate repair at 18 to 36 months., Main Outcome Measure: Averaged ratings of dental casts using the 5-year yardstick were computed for each patient. The Wilcoxon two-sample test was used to compare means; a chi-square test was used to compare distributions., Results: Intra- and interexaminer reliability tests showed excellent reliability (>.90). Mean scores were not significantly different. Distribution of scores differed significantly. Center A had the highest percentage of good scores and the lowest percentage of poor scores (72% versus 6.5%), followed by center B (63% versus 6.6%) and center C (59% versus 16.3%)., Conclusions: Centers A and B had comparable scores and completely different protocols in surgical technique, timing, sequencing, and nonuse/use of appliances. Center C's results were slightly lower than those of 1 and 3, but the center had the protocol with the least burden of treatment (only two surgeries, without use of appliances).

Aim: A questionnaire was sent to orthodontists with private practices in the German State of Hesse to obtain information about the frequency of rapid palatal expansion and complications during treatment with rapid palatal expansion appliances (RPE-A)., Material and Method: A series of questions therein inquired as to the types of RPE-As used, their activation rhythm, the extent and the duration of the active expansion and retention; what their age limit was, starting from when surgical assistance was deemed necessary. Another series of queries concerned any technical and medical complications observed., Results: The most frequently used type was the Hyrax screw (75%) soldered to bands. Technical problems arose with all applied indicated types. Although the answers to the first series of questions showed great variance, the majority of the orthodontists activated the screw twice a day (range 1-6 times a day) by a quarter turn for 2-3 (range 1-12) weeks. The retention phase amounted to 12 (range 4-26) weeks and the age limit for the indication of a surgical intervention was on average 17 years, with a range of 10-35 years. Medical complications such as pain and decubitae were reported by a third of the inquired offices, a non-opening suture was observed in one of every five practices. This meant that 1.7% of the sutures failed to open, and tooth tilting and rarely, extreme root resorptions and/or bone dehiscences were observed. Solid carious lesions were observed in one case after removal of an adhesive RPE. Extraoral changes such as those in the nose were reported by one in every ten practices., Conclusions: The RPE represents a common treatment means during which side effects are often temporary and permanent damages rather rare. It is important to inform the patient about both positive effects and possible complications, in particular pain and extraoral changes.

Objective: To assess the demand and pattern of referral for orthodontic services at University College Hospital, Ibadan, Nigeria., Design: A 21-month prospective clinic-based study of consecutive orthodontic patients., Setting and Sample Population: The orthodontic clinic of University College Hospital, Ibadan, Nigeria. One hundred and seventy-eight (178) consecutive patients, consisting of 79 (44.4%) males and 99 (55.6%) females with mean age of 16.21+/-7.81 years were studied., Results: 80% of subjects were 20 years of age or younger, while less than 2% were over 40 years of age. More females sought orthodontic care than males. Over 43% of the patients needed removable orthodontic appliances while close to 17% required treatment with fixed appliances. Extractions of retained primary teeth and other grossly malpositioned teeth accounted for 9.6% while 24.7% needed observation of occlusal developments before any treatment decisions could be made. Dentists were noted to be the main referrers of these patients, accounting for over 49% of the referrals, followed by 25.4% who were self referred, and 18.3% who attended under parental influence., Conclusion: More girls than boys demanded orthodontic care and dentists were the major referrers of orthodontic patients.

Previous studies of the morphologic changes of the maxilla after palatal expansion have used 2-dimensional methodologies. In the present study, we used a 3-dimensional surface laser scanning technique and computerized cast analysis, in addition to analysis of anteroposterior cephalograms, to assess the morphologic changes of the palate by 2 kinds of expanders: tissue borne (Haas; n = 9) and tooth borne (Hyrax; n = 10). Cast analysis demonstrated that, although all patients started treatment with similar malocclusion, treatment outcomes were different depending on the appliance used. Both appliances generated maxillary expansion (ie, improved mean surface area, mean intermolar linear distance, and mean perimeter) (P <.05). However, the appliances performed differently to achieve the final expansion. Haas appliances demonstrated a greater orthopedic movement (ie, improvement of the mean interpalatal distance) (P <.05), and Hyrax appliances demonstrated dentoalveolar expansion by increasing the mean palatal angulation of the alveolus (P <.05). Anteroposterior cephalometric analysis showed that both appliances increased mean maxillary width and mean intermolar distance significantly (P <.05). On the other hand, differences in nasal cavity width and upper incisal apex distance were not statistically significant (P >.05). This new 3-dimensional methodology proved useful for comparing treatment outcomes by evaluating the morphologic changes induced by palatal expansion and generated a better visualization of these outcomes.

The occupational stress associated with many professions, including general dentistry, has been well researched. An anonymous, self-administered, mail-out survey was distributed to Canadian orthodontists. The survey included 67 potential stressors, an overall occupational stress score, an overall job satisfaction scale, and items addressing various characteristics of the respondents. The response rate was 51.2% (335/654). Pronounced differences were found between the respondents in the evaluation of potential stressors and the overall occupational stress score. The category of stressors with the highest mean severity of stress scores was time-related stressors. The stressors with high mean severity scores and high mean frequency scores were as follows: falling behind schedule, trying to keep to a schedule, constant time pressures, patients with broken appliances, and motivating patients with poor OH and/or decalcification. Stepwise multiple regression determined a model, involving overall job satisfaction, age, participation in a study group, hours worked per week, part-time academics, days of continuing education per year, and participation in stress management, to account for 35.9% of the variation in overall occupational stress scores. The results indicate the importance of time-management skills in reducing occupational stress, but other factors seem to have more effect on reported occupational stress than do the characteristics addressed by this survey.

Background: To reduce the skin nickel exposure of the population, the Danish Ministry of Environment issued a regulation that was implemented in 1992, and the European Union countries have recently adopted an expanded regulation., Objectives: The aim of our combined patch testing and questionnaire investigation of girls in public schools and high schools/production schools was to evaluate whether the regulation has had an impact on the prevalence of nickel sensitization., Methods: To find a group of girls with ears pierced mainly after implementation of the nickel-exposure regulation in Denmark, girls were recruited from the fifth and sixth grade in 12 public schools (the public school group). After the public school level almost all girls from a public school population continue their education in high schools or other schools such as production schools or technical schools. Therefore, to find girls demographically similar to the public school girls but older, and with ears pierced before implementation of the regulation, girls from seven high schools and two production schools were recruited (the high school group). Four hundred and twenty-seven girls in the public school group (mean age 12.4 years, range 10-14) and 534 in the high school group (mean age 18.8 years, range 17-22) participated. All participants filled out a questionnaire concerning ear piercing, use of oral braces and former patch testing for nickel sensitivity. Three hundred and five girls (71.4%) in the public school group and 275 (51.5%) in the high school group were patch tested or had been tested previously and the results of these tests were included in the study. The relation between the frequency of nickel sensitization and the various factors that might influence the prevalence of nickel sensitization was evaluated by multivariate logistic regression analysis. The investigation was conducted from March 1999 to March 2000., Results: The study showed that both increasing age and having ears pierced before 1992 enhanced the prevalence of nickel sensitization. We found that 17.1% of the girls in the high school group demonstrated a positive patch test reaction to nickel. In contrast, the prevalence of nickel sensitization in the public school group was only 3.9%. Comparing girls with and without pierced ears, the prevalence of nickel sensitization was significantly higher in girls with ears pierced before, but not after, 1992 (odds ratio 3.34 and 1.20, respectively). Only in the high school group was there a tendency that wearing oral braces before ear piercing had a protective effect on nickel sensitization, but this did not reach statistical significance., Conclusions: As we found an effect of ear piercing before but not after 1992, this study strongly suggests that implementation of the nickel-exposure regulation in 1992 in Denmark has had the intended effect of protecting the female population from becoming allergic to nickel.

In Australia, the proportion, volume and type of orthodontic care provided by general practitioners and orthodontists are largely unknown. The overall objective of this study was to create a profile of orthodontic services provided by general practitioners and orthodontists for a cohort of insured patients using private practices in New South Wales, Australia, from 1st January 1992 to 31st December 1995. Data were derived from claims records submitted by members of a health insurance fund for rebates for fees paid to private practitioners for orthodontic services they received during the study period. Distribution of the volume and type of service provided by general practitioners and orthodontists was compared using the Chi-squared test. Statistical significance was taken at the 5 per cent level. Orthodontic services were provided predominantly by orthodontists (80%). Fixed orthodontic treatment was provided almost exclusively (91%) by orthodontists. The majority of removable appliance services was provided by general practitioners. Orthodontists provided more orthodontic services in the capital city and other metropolitan areas, whereas general practitioners provided more orthodontic services in rural areas. Orthodontists provided more services to members in the highest socio-economic group, whereas general practitioners provided more services to members in the lowest socio-economic group.

The purpose of this retrospective study was to determine the prevalence and types of dental emergencies occurring in a university-based, pediatric dentistry postgraduate outpatient clinic. All patients presenting for emergency dental care during scheduled clinic hours over a three year were identified, and their charts were retrieved. Each record was reviewed for demographic information, chief complaint and clinical diagnosis. Only those charts with both chief complaints and clinical diagnoses recorded were included in this study. A total of 816 patients received emergency care, representing 15.3 percent of all patient treated during the study period. The patient population had a slight female predilection (53 percent female, 47 percent male) and a mean age of 5.1 years (range 10 days to 15 years). Ethnicity (39 percent African-American, 36 percent Hispanic, 24 percent Caucasian <1 percent Asian-American) was similar to that for the clinic in general. Reimbursement for dental care was primarily via Medicaid (91 percent) with <10 percent covered by insurance or payment by responsible parents. For one quarter of the children, the emergency visit was their first dental visit. Reasons for seeking emergency included 1) pain or discomfort due to caries [30.1 percent] with 27 percent due to early childhood caries; 2) dental trauma [23 percent];3) eruption difficulties [18 percent] with 27 percent due to early childhood caries; 2) dental trauma [23 percent];3 eruption difficulties [18 percent];4) soft tissue pathoses [16 percent]; 5) problems with orthodontic appliances or space maintainers [10 percent]; and 6) lost restorations [2 percent]. Pain and bleeding were the most common reasons for seeking emergency dental care. Most causes for seeking outpatient emergency dental care are disease processes which may be avoided by infant oral health and preventive dentistry programs and early treatment intervention.

This article enables pediatricians to identify and understand the implications of common facial growth problems in children and adolescents. Problems with facial growth can result in aesthetic and functional concerns. Using a simple method of clinical evaluation, pediatricians can identify facial growth problems in the anteroposterior, vertical, and transverse dimensions. These problems can then be referred for evaluation and treatment by various means. Because facial growth is the result of the interaction of genetic and environmental factors (some of which are functional), growth modification may be a possibility. Some problems may be camouflaged or treated by combined surgical and orthodontic means. Continued growth in early adulthood may enhance or detract from treatment results obtained in childhood or adolescence. These dynamic properties of the face make management of facial growth challenging but generally rewarding and successful because of substantial aesthetic and functional improvements.

Class II mechanics are supposed to affect the vertical balance of the face when they are used in hyperdivergent patterns. We carried out a study about class II mechanics effects on 100 patients; 50 of them are hyperdivergent (GoGn/SN > or = 37), and 50 non-hyperdivergent. They all were treated with an Edgewise appliance without any high pull head gear. The authors showed that GoGn/SN angles and Occ/SN tend to be lessened in a skeletal open-bite population. Thus, Class II mechanics can be prescribed in any vertical facial pattern.

The aim of this study was to evaluate the long-term stability of the occlusion after correction of posterior cross-bite with either a removable expansion plate or a quad-helix appliance and to compare the transversal development of the jaws in the plate group, the quad-helix group and a control group. At the start of treatment there were 22 children in each of the treated groups. Two children in the plate group and 1 child in the quad-helix group discontinued the treatment. Two children treated with the quad-helix appliance and 1 child in the plate group could not be reached for the follow-up registration, so the collective finally consisted of 30 boys and 27 girls: 19 subjects in the plate group, 19 in the quad-helix group and 19 controls. The treatment groups were studied with the help of plaster models before treatment, immediately after treatment and at the last registration about 5.5 years after treatment. The control group was studied with the help of plaster models on 2 occasions, at the mean age of 8.8 years and 15.9 years respectively. This was about the same age as the first and the last registrations in the treatment groups. In all children, the posterior cross-bite was corrected by the end of the treatment. At the last registration, the corrected posterior cross-bite had relapsed in 1 child in the plate group and in 3 children in the quad-helix group. The degree of expansion was similar for both groups. The mean treatment time was longer in the plate group than in the quad-helix group: 12.5 months and 7.7 months respectively. Despite a transversal expansion in the treatment groups, the width of the maxillary dental arch did not reach the mean width in the control group, and even at the last registration the width of the maxillary dental arch was significantly greater in the control group than in the treated groups. The conclusions of this study are: 1. The long-term treatment effect in children with posterior cross-bite was somewhat better when they were treated with the removable expansion plate in comparison with treatment with the quad-helix appliance. 2. Both immediately after treatment and at the last registration 5.5 years later, the width of the maxillary dental arch was significantly greater in the control group than in the plate group or the quad-helix group while the width of the mandibular dental arch was equal in all 3 groups.

Whilst a patient is undergoing orthodontic treatment, dental appliances based on non-precious metals or titanium remain in the oral cavity for up to several years. Throughout this period the appliance is in either direct or indirect contact with the oral mucosa. To investigate the possibility of cell damage occurring as a result of appliance corrosion, monolayer cultures of immortalized human gingival keratinocytes were assessed for acute cyto- and genotoxicity using the hexosaminidase assay and the Comet assay respectively. The materials tested included 1. a nickel-free wire, 2. a UK-1 bond, 3. nickel-free as well as nickel-containing brackets with and without color signature and 4. a titanium expansion screw. Each of the test materials was corroded in a solution consisting of equal amounts of lactic acid and sodium chloride (0.1 M) for 1, 3, 7 and 14 days. The cell cultures were then exposed to eluates exhibiting the highest ion concentrations. None of the eluates was found to exhibit acute cytotoxicity, regardless of the type of test system used. Qualitative assessment using neutral red dye for live cells and either trypan blue or propidium iodide to disclose dead cells failed to reveal any significant increase in cell damage when exposed cells were compared to control cultures. Unrestricted cell vitality was confirmed by quantifying viable cells through measurement of hexosaminidase enzyme activity. Furthermore, assessment of genotoxicity revealed no apparent DNA damage to immortalized gingival keratinocytes following exposure to the test eluates. Because the materials tested in this study were corroded using the exacting methods normally applied to precious metals or gold-containing alloys, the lack of either acute cyto- or genotoxic effects following exposure to the test eluates indicates that the materials tested exert no adverse effects on cells similar to those of the target tissue exposed to the materials in situ.