Impact of early extraction of the deciduous canine on relief of severe crowding.

OBJECTIVES: To explore whether there were any differences in orthodontic treatment need, treatment complexity, treatment time, or the number of visits between a group of children receiving early intervention (extraction of upper and lower deciduous canines) and an age- and condition-matched control group without intervention. MATERIALS AND METHODS: Patient records and study casts in the late mixed or early permanent dentitions of 46 subjects (20 from the extraction group and 26 from the control group) of an earlier prospective longitudinal study were retrieved. Orthodontic treatment need and complexity were assessed by the index of complexity, outcome, and need (ICON). Statistical calculations were performed by t-test for parametric outcome variables (treatment time, number of visits, and orthodontic treatment need) and Fisher exact test for the categorical variable (tooth extractions). RESULTS: There were no statistically significant differences between the groups in ICON scores of orthodontic treatment need (extraction group, mean score 59.8; control group, mean score 52.8), number of visits (mean of about 15 visits for both groups), or treatment time (extraction group, mean 21.5 months; control group, mean 20.3 months). The extraction of permanent teeth was more prevalent in the deciduous canine extraction group (59%) as compared with the control group (28%); however, this was not statistically significant (P = .07) but showed a tendency toward worsening the crowding and the future need of orthodontic extractions. CONCLUSIONS: Early removal of deciduous primary canines will reduce neither the need for later orthodontic treatment nor its complexity, nor will it shorten the treatment time.

Distinguishing between global and dental self-esteem in evaluating malocclusions.

Objective: When dealing with the impact of malocclusion on self-esteem, the terms global and dental self-esteem are sometimes used. Although these terms are related to one another, they do not depict the same concept. The aims of this paper were to explore if the two forms of self-esteem are distinguishable, to find out if they represent different factors, and to investigate how they are related to malocclusion. Materials and methods: A sample consisting of 150 adolescents, aged 13 years, completed self-assessed measures of Dental and Global Self-Esteem. Orthodontic treatment need for each individual was assessed by the Dental Health Component of the Index of Orthodontic Treatment Need (IOTN-DHC). Data were analysed by factor analyses and a 5 (IOTN-DHC grades) by 2 (global vs. dental self-esteem) ANOVA, with the IOTN-DHC grades as the independent and self-esteem (repeated measure) as the dependent variables. Results: The factor analyses showed that the two forms of self-esteem, based on the measures, are distinguishable. More importantly, the results of the ANOVA revealed that Dental and Global Self-Esteem are differentially related to IOTN-DHC. Specifically, Dental Self-Esteem varied across IOTN-DHC scale while Global Self-Esteem did not. There was no effect of gender. Conclusions: Dental self-esteem is related to malocclusion while global self-esteem is not. These findings have implications in areas where the predictive power of dental self-esteem needs to be considered.

Pain relief after orthodontic archwire installation-a comparison between intervention with paracetamol and chewing gum: a randomized controlled trial.

BACKGROUND: Pain and discomfort are main concerns at the commencement of orthodontic treatment. It may have negative impact on compliance or even discourage patients from being treated. Orthodontic pain can be alleviated by paracetamol or use of chewing gum. However, studies comparing their effectiveness are scarce. OBJECTIVES: To compare the effectiveness of paracetamol versus chewing gum for pain alleviation and to investigate the frequency of bracket loss during the first day of fixed orthodontic treatment. TRAIL DESIGN: Prospective randomized multicentre clinical trial. METHODS: Sixty patients (28 boys and 32 girls), between 12 and 18 years of age were randomly allocated either to take paracetamol (31 patients) or to use chewing gum (29 patients). After one arch bonding and insertion of the initial archwire, the patients rated the sensation of pain on a visual analogue scale with the jaw at rest and when biting after 6 hours (T1), at bedtime (T2), and the next morning (T3). Paracetamol (1000 mg) was taken 1 hour and chewing gum was used 10 minutes prior to pain rating at T2 and T3. A simple method of randomization was used in this study, and blinding of subjects and the operators to the type of intervention was not possible because of the nature of the treatments. RESULTS: There was no detectable difference in pain sensation between the groups at T1. At T2 and T3 the chewing gum group displayed higher mean values than the paracetamol group but when adjusting for age, gender, and mode of pain registration, there was no significant difference between the groups. There was no bracket loss in the chewing gum group, whereas two patients in the paracetamol group lost two brackets. CONCLUSIONS: The effect of chewing gum and paracetamol for initial orthodontic pain relief seems equivalent. Short term use of chewing gum is not a risk factor for bracket loss. TRIAL REGISTRATION: This study was not registered.

Determinants of orthodontic treatment need and demand: a cross-sectional path model study.

OBJECTIVES: To put forward a model predicting orthodontic treatment need and demand. Furthermore, to explore how much of the variance in treatment demand could be explained by a set of self-assessed measures, and how these measures relate to professionally assessed treatment need. SUBJECTS AND METHODS: One hundred and fifty adolescents, aged 13 years, completed a questionnaire which included a set of self-assessed measures dealing with self-esteem, such as dental and global self-esteem, various aspects of malocclusion, such as perceived malocclusion and perceived functional limitation, and treatment demand. Treatment need was assessed by Dental Health Component of the Index of Orthodontic Treatment Need grading. Path analysis was used to examine the relations between the measures and if they could predict treatment need and demand. RESULTS: The measures proved to be reliable and inter-correlated. Path analysis revealed that the proposed model had good fit to the data, providing a test of the unique effect of all included measures on treatment need and demand. The model explained 33% of the variance in treatment demand and 22% of the variance in treatment need. LIMITATIONS: The specific age group could affect the generalizability of the findings. Moreover, although showing good fit to data, the final model is based on a combination of theoretical reasoning and semi-explorative approach. CONCLUSIONS: The proposed model displays the unique effect of each included measure on treatment need and demand, explaining a large proportion of the variance in perceived treatment demand and professionally assessed treatment need. The model would hopefully lead to improved and more cost-efficient predictions of treatment need and demand.

Predicting orthodontic treatment need: reliability and validity of the Demand for Orthodontic Treatment Questionnaire.

Objectives: To identify key measures in predicting orthodontic treatment need and to propose a self-assessment instrument that improves treatment need assessment. Subjects and methods: The study included 150 randomly selected 13-year-olds. A set of measures linked to a previous study on daily life impact of malocclusion was processed, resulting in an instrument, the Demand for Orthodontic Treatment Questionnaire (DOTQ), which was analysed regarding dimensionality, reliability and validity. Dental Health Component of the Index of Orthodontic Treatment Need (IOTN-DHC) grading, representing professionally assessed treatment need, were collected from dental records. The instrument's ability to predict treatment need was tested by randomly splitting the dataset into two subgroups, using multiple regression to predict DHC in one of the groups and the prediction equation to calculate predicted DHC in the other. The outcomes were then correlated to detect the predictive power of the DOTQ, and thereby the validity of the prediction. Results: The DOTQ-measures were reliable and highly inter-correlated. A high, significant correlation was found between assessed and predicted treatment need for the subgroups (r = 0.59 and 0.49), confirming the validity of the prediction. Independent variables (the measures) explained 47 per cent (R = 0.69) of the variance in treatment need. Four measures contributed significantly to the prediction, with Treatment Demand being the most powerful predictor. Limitations: The age group and response rate may raise some questions regarding the generalizability of the findings. Conclusions: The DOTQ is able to predict treatment need as assessed by orthodontic consultants. Its incorporation in the treatment need assessment process will acknowledge patients' self-perceived impact of malocclusion.

Daily life impact of malocclusion in Swedish adolescents: a grounded theory study.

OBJECTIVE: To explore how malocclusions affect daily life in adolescents and how adolescents cope with malocclusion-related distress. MATERIALS AND METHODS: Twelve strategically selected teenagers, seven girls and five boys aged 13-14 years, participated in this study. Open, tape-recorded in-depth interviews based on Focus Group Discussions (FGD) were performed using a theme guide and analyzed according to the qualitative method of classic grounded theory (GT). RESULTS: A core category was identified and named 'Repeatedly reminded of the malocclusion'. Associated to the core category, five categories were generated and labeled 'Being directed by the media's ideal image', 'Monitoring others' teeth', 'Struggling with low self-esteem', 'Hiding one's teeth' and 'Striving for cure'. Low self-esteem appeared to be frequently reinforced through the concerns for the malocclusion and handled via different coping strategies, such as hiding the teeth and striving to receive orthodontic treatment. Such processes were further enforced through the influence of media. Low self-esteem could be associated to a visible malposition of teeth, according to the informants. Having to wait for orthodontic treatment was frustrating the adolescents. CONCLUSIONS: Adolescents with malocclusion are often reminded of their condition, which can lead to avoiding strategies to minimize the negative feelings associated with the teeth and low self-esteem. Clinicians may therefore need to be aware of potential irrational behaviors when interacting with adolescents with malocclusions. The findings also suggest that there might be a discrepancy of attitudes between professionals focusing on oral health aspects of malocclusions and the adolescents focusing on esthetic aspects.

Mandibular incisor alignment and dental arch changes 1 year after extraction of deciduous canines.

This study investigated the early effects on mandibular incisor irregularity and rotation together with dental arch dimensions of the extraction of four deciduous canines. Children, during early mixed dentition, were randomized into one extraction (n = 32) and one control (n = 41) group. Dental casts from baseline (T0) and 1 year follow-up (T1) were used to evaluate changes in the irregularity index and in mandibular incisor rotation, dental arch dimensions, overjet, and overbite. Median mandibular incisor irregularity decreased over time, significantly more in the extraction than the control group (1.2 versus 0.7 mm; P < 0.01), with wide ranges in both groups. Rotational changes greater than 10 degrees for lateral incisors were twice as common in the extraction group (42 versus 20 per cent; P < 0.01). Central incisors displayed only minor changes in both groups. The correlation between changes in irregularity index and changes in incisor rotation was weak in both groups (r(s) < 0.3 not significant). According to professional assessment of overall alignment, 84 per cent in the extraction group versus 34 per cent in the control group (P < 0.001) improved from T0 to T1. A significant decrease in maxillary and mandibular arch length and circumference from T0 to T1 was recorded in the extraction group (1.3, 1.1 mm and 2.4, 2.0 mm, respectively; P < 0.001), while arch dimensions were preserved in the control group. To conclude, 1 year after extraction of the deciduous canines, small improvements in mandibular incisor alignment were seen, together with reduced arch dimensions. Little's index underestimated malalignment related to tooth rotation.

Pain and fear in connection to orthodontic extractions of deciduous canines.

BACKGROUND: Interceptive extractions of deciduous canines are, from a patient perspective, poorly investigated. AIMS: To describe pain, discomfort, and dental fear in connection to extractions of the deciduous canines, indicated as an orthodontic treatment procedure. DESIGN: Thirty-two Swedish children aged 7-9 years had all four deciduous canines extracted over three occasions. The children rated procedural and postoperative pain on visual analogue scales. Acceptance of injections and extractions was assessed by the treating dentists. Analgesic consumption and recovery time for drinking and eating was reported by parents. Dental fear was assessed using the Children's Fear Survey Schedule questionnaire. RESULTS: Procedural pain showed low median levels, although some individuals reported high values. Boys reported significantly more pain at appointments when two (as opposed to one) canines were extracted. Postoperative pain levels were low and use of analgesics sparse. Dental fear paralleled norm values and did not increase from pre- to post-extraction. CONCLUSIONS: Pain management routines during extractions of this kind should be revised. Single tooth extractions seem to be preferable to extractions of two canines at the same appointment. Extraction of four deciduous canines should not cause major postoperative inconvenience; these extractions neither triggered nor increased dental fear.

Orthodontic study cast analysis--reproducibility of recordings and agreement between conventional and 3D virtual measurements.

Digital imaging of dental casts has become an alternative to conventional cast analysis in orthodontic treatment planning. The reproducibility of angular measurements made on virtual digital models has not as yet been evaluated. In order to study reproducibility for and agreement between a conventional analysis technique and virtual 3D imaging, 20 dental casts from subjects in the early mixed dentition, were measured twice with each technique by two orthodontists. Variables of interest were incisor rotation, angulation and irregularity, arch width, arch circumference, overjet, and overbite. Standard deviation (Dahlberg 1940) and coefficient of variation were used for evaluation of reproducibility. Mean differences between methods and examiners, correlation between mean differences and mean levels and 95% limits of agreement were used for describing systematic errors. The conventional technique showed less intraexaminer variation for angular variables than the 3D imaging method. Linear variables, with the exception of overbite, showed no clear trend as regards differences in reproducibility between the two methods. In general, examiner 1 showed less intraexaminer variation than examiner 2. The mean differences between the two methods expressed higher values for assessment of rotations with the O3DM method. Both angular and linear variables exhibited poor 95% limits of agreement. The conventional technique showed better overall reproducibility and thus appears to be more suitable for scientific work. However, the reproducibility attained by O3DM is clearly acceptable for clinical use. The two methods should not be used interchangeably.

Uniformity in selection for subsidized orthodontic care--focus on borderline treatment need.

In the county of Stockholm, subsidized orthodontic care is offered to roughly 25% of persons under the age of 19. Stockholm County Council has signed contracts with experienced orthodontists (consultants) to carry the responsibility of screening and offering subsidized treatment to those having the most urgent treatment need. For this purpose the orthodontist is free to use whatever yardstick he/she finds most useful. The Swedish Medical Board Index (SMBI) is most commonly used, and was used by the consultants in this study. It is obvious that the selection process under these conditions must be affected by a subjective opinion and consequently the inter-examiner variation would be large, especially for subjects presenting with borderline treatment need. The aim of the study was to evaluate the uniformity in selection of subjects for subsidized orthodontic care with focus on borderline treatment need. Six consultant orthodontists volunteered to participate. Each orthodontist was asked to recruit patients whom they considered to have borderline treatment need. 34 adolescents; 25 girls and 9 boys (mean age 14.5 +/- 1.68 years), were recruited. These patients were individually assessed by each orthodontist. The interexaminer agreement was tested by use of Cohen's kappa statistics (kappa = 0.324). Since all six orthodontists fully agreed in only one third of the cases the validity of the assessments with the present guidelines is insignificant, at least in subjects with borderline treatment need.

Craniofacial morphology, head posture, and nasal respiratory resistance in obstructive sleep apnoea: an inter-ethnic comparison.

The aim of this study was to measure craniofacial morphology and nasal respiratory resistance (NRR) in Malay, Indian and Chinese subjects with obstructive sleep apnoea (OSA). The sample consisted of 34 male subjects, 27-52 years of age (Malay n = 11, which included five mild and six moderate-severe OSA; Indian n = 11, which included six mild and five moderate-severe OSA; and Chinese n = 12, which included six mild and six moderate-severe OSA) diagnosed using overnight polysomnography. After use of a decongestant, NRR was recorded using anterior and posterior rhinomanometry. Standardized lateral cephalometric radiographs were used to record linear and angular dimensions. Malay subjects with moderate-severe OSA had a shorter maxillary (sp-pm) and mandibular (gn-go) length when compared with a mild OSA reference sample (P < 0.05). The hyoid bone was located more caudally in the Chinese moderate-severe subjects (hy-NL, hy-ML)(P < 0.05), and may be a useful diagnostic indicator for severity in this racial group. No pattern of differences for NRR was seen between the moderate-severe and mild OSA subjects. The consistently lower values for nasopharyngeal resistance in all the moderate-severe subjects when compared with the mild group may indicate that some compensation at this level of the airway had taken place. Strong positive correlations between craniocervical angulation (NL/OPT) and total airway resistance and the turbulent component of flow (k(2)) suggest that head posture is sensitive to fluctuations in airway resistance (P < 0.01).

Trunk asymmetry and facial symmetry in young adults.

The aim of the present study was to detect possible associations between trunk and cervical asymmetry and facial symmetry. Frontal cephalograms prepared in the natural head position, representing 79 subjects (40 males, 39 females) with mild to moderate trunk asymmetry, were analyzed separately for thoracic humps, lumbar prominences, and cervical inclination by discriminating two groups: right-sided-dominant and left-sided-dominant. The differences between the groups were analyzed using an unpaired 2-group t test. The results showed that location of the thoracic humps and inclination of the cervical spine was predominantly right-sided, while the location of lumbar prominence was predominantly left-sided. Craniofacial morphological variables of the head and face were nearly equal for right-sided and left-sided thoracic humps and lumbar prominences, showing that moderate trunk asymmetry does not affect facial symmetry. Further, it was found that frontal head position in relation to the true vertical (VER/ORB) is stable in that the angle between the supraorbital and vertical lines is constantly maintained close to 90 degrees regardless of moderate trunk asymmetry, indicating that visual perception control is most important in orienting the head in frontal plane. Maintenance of the head position takes place by cervical spine adaptation.

Evaluation of the validity of tooth size and arch width measurements using conventional and three-dimensional virtual orthodontic models.

Measurements and different analyses of dental casts are essential for precise diagnosis of an orthodontic case. At present, virtual computerized models, such as OrthoCAD, are available for clinicians, supplemented by dedicated software for performing needed measurements on them. The purpose of this study was to test the accuracy of measuring casts with the aid of calipers or OrthoCAD and compare these two techniques. Twenty setups using artificial teeth corresponding to various malocclusions were created. Impressions were taken of them, providing 20 plaster and 20 virtual orthodontic models. Measurements of mesiodistal tooth dimension as well as intercanine and intermolar width were made on both. Additionally, values of tooth size were calculated from the isolated artificial teeth removed from the setups and of arch width from the existing setups. The resulting values were compared by the use of nonparametric statistics, and methods' errors were also calculated. Results showed the methods being highly valid and reproducible for both tooth size and arch width. For the tested clinically applicable methods, measurement with digital calipers on plaster models showed the highest accuracy and reproducibility, closely followed by OrthoCAD. Digital calipers seem to be a more suitable instrument for scientific work. However, OrthoCAD's accuracy is clinically acceptable, and most likely, considering its present advantages and future possibilities, the examined or an equivalent 3D virtual models' procedure would become the standard for orthodontic clinical use.

Craniofacial morphology in obese adolescents.

Overweight and obesity are growing problems in the world today. A recent survey shows that about 30% of the adolescent and adult Swedish population is overweight or obese. The etiology is a combination of many factors, the most important of which are physical inactivity and high caloric diet. Obese children have a normal to accelerated growth rate despite low growth hormone (GH) levels. The aim of our study was to investigate whether craniofacial morphology differs between obese adolescents and normal weight adolescents. Lateral cephalograms from 39 adolescents with obesity, aged 14-16 years, were analysed and compared with lateral cephalograms from an equal number of sex- and aged-matched controls. Compared to the controls, the subjects in the obesity group showed increased mandibular length, prognathic jaws and a reduced upper anterior face height. Despite low GH levels, obese children have normal levels of insulin-like growth factor (IGF-1). Since we found an advanced craniofacial growth in obese adolescents with low GH and high IGF-1 serum levels, craniofacial growth may be more dependent on free circulating LGF-1 than on the locally produced portion.

Is tooth agenesis related to brainstem anomalies in myelomeningocele patients with Chiari II malformations?

Defects in the prenatal development of the brainstem can result in cranial nerve deficiencies. As the development of tooth germ is dependent on n. trigeminus, which originates from the brainstem, the hypothesis underlying this study was that anomalies of the brainstem would lead to an increased prevalence of tooth agenesis. Twenty-three patients (13 F and 10 M, age range 6-37 years) were studied, all with myclomeningocele and brainstem anomalies (Chiari II). They were examined retrospectively from the data in journals and dental radiographs and compared to available data on the prevalence of tooth agenesis in the Swedish population. Our hypothesis was rejected, since there was insignificant difference in the frequency of agenesis in our material (8.7%) compared with that of the Swedish population (7.4%).

Maximal bite force and its associations with spinal posture and craniofacial morphology in young adults.

Maximal bite force (MBF) and its associations with craniofacial morphology and spinal posture were studied in a group of young adults (46 M and 38 F) aged 21 to 23 years. MBF was recorded in molar and incisal regions. Sagittal spinal posture was measured by spinal pantography and trunk asymmetry at thoracic and lumbar levels by a forward-bending test. Craniofacial variables and posture of the cervical spine were examined from lateral cephalograms taken in a natural head position. No statistically significant correlations existed between MBF and spinal posture, but significant correlations did exist between MBF and craniofacial variables, especially in women.