Terttu Pietilä

Acceptability of dental appearance in a group of Finnish 16- to 25-year-olds.

OBJECTIVE To define a grade in the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN) that would differentiate between esthetically acceptable and unacceptable occlusions and that would also be both subjectively and objectively meaningful. MATERIALS AND METHODS Dental appearance and self-perceived orthodontic treatment need were analyzed in a group of Finnish young adults (171 males, 263 females, age range 16-25 years). Subjective data were gathered using a questionnaire, and the respondents were requested to score their dental appearance on a visual analog type 10-grade scale. Professional assessment of dental appearance was performed by two orthodontists using the AC of the IOTN. The cutoff value between esthetically acceptable and unacceptable occlusions was defined using receiver operating characteristic curves. RESULTS Sixty-six percent of orthodontically treated and 74% of the untreated respondents were satisfied with their own dental appearance. Every third respondent reported one or more disturbing traits in their dentition. The most frequently expressed reason for dissatisfaction was crowding; girls expressed dissatisfaction more often than boys did (P = .005). A self-perceived treatment need was reported infrequently by 8% of orthodontically treated and 6% of untreated respondents. In the logistic regression analysis, self-perceived need for orthodontic treatment was the only significant factor explaining dissatisfaction with own dental esthetics. On the applied scales, grades 1 and 2 fulfilled the criteria for satisfactory dental esthetics. CONCLUSION The results suggest that the AC grade 3 could serve as a cutoff value between esthetically acceptable and unacceptable occlusions.

Occlusal status in orthodontically treated and untreated adolescents

In order to evaluate the outcome of orthodontic care, all available 16-year-old adolescents (n = 138) living within the catchment area of one Finnish health center were invited for a clinical examination. A total of 126 adolescents participated, corresponding to 79% of the whole age cohort. Of these, 47% had been treated orthodontically, 2% were still wearing appliances, and 51% were untreated. In 80% of cases, a non-extraction treatment was carried out. All occlusions were evaluated using a recently developed occlusal morphology and functional index (OMFI) based on assessment of 6 morphological and 4 functional traits which are classified applying an acceptable-non-acceptable dichotomy. The occlusal status in untreated individuals was used as a second reference in comparisons between the treated and untreated occlusions. The morphological criteria for an acceptable occlusion were met by 42% of the participants and the functional criteria by 64%. Although the treated occlusions failed to meet the criteria of morphological acceptability more often than the untreated ones (73% vs 40%), the proportions of non-acceptable occlusions were fairly high among untreated occlusions. The main reasons for non-acceptability were the failure of the canine relationship, overbite, and protrusion movement to fulfill the criteria of acceptability. Only 19% of the adolescents had occlusions classified as acceptable, both morphologically and functionally. In the evaluated health center, the allocation of resources resulted in a high coverage of orthodontic care. However, our results indicate that the general occlusal status in the examined age cohort did not reach an optimal level.

Selection of criteria for assessment of occlusal acceptability

There is no general agreement on criteria that could be applied to distinguish between orthodontically acceptable and non-acceptable occlusions after the completion of dental development. The aim of the present study was to analyse morphological and functional features that could be used as an index to define an acceptable occlusion in young adults. Three expert panels representing specialists in orthodontics and stomatognathic physiology participated in a modified Delphi method. Each panel responded to a questionnaire concerning the usefulness of various occlusal features, and a set of characteristics was selected on the basis of the responses; thereafter, applicability of the chosen characteristics and their cutoffs for an acceptable-non-acceptable dichotomy was tested clinically. To obtain a consensus level of 100%, the last panel session was completed with a group discussion. Assessments made using the morphological criteria were compared with those made with the dental health component of the Index of Orthodontic Treatment Need. The selected morphological characteristics consisted of overjet, overbite, canine relationship, crossbite, scissors bite and midline deviation. The functional evaluation comprised assessments of discrepancy between the centric relation and the intercuspal position, working- and non-working-side contacts and protrusion contacts. The dental health component and our morphological criteria showed different sensitivity to contact point displacements, interdigitation in buccal segments and increased overbite. This study provides a set of morphological and functional indicators reflecting the current consensus opinion of Finnish professionals. Further studies are needed to analyse the reproducibility of assessment of the characteristics included.

Orthodontic treatment practices in Finnish municipal health centres with differing timing of treatment

The aim of this study was to compare orthodontic practices in eight Finnish municipal health centres selected on the basis of an earlier survey to represent early and late timing of treatment. The health centres were grouped according to the mean age of starting treatment; earlier versus later than 9 years of age. A random sample of 16 and 18 year olds (n = 2325) living in these municipalities were invited for a clinical examination, and 1109 adolescents participated. The participants reported on their previous or ongoing orthodontic treatment by means of a questionnaire. Data on orthodontic treatment received were collected from the dental files of the adolescents who reported a treatment history and for those who did not recall exactly whether or not they had received orthodontic treatment. Analysis of the non-respondents was made on the basis of their dental files. Differences between the features of orthodontic treatment in the early and late starting health centres were analysed using a two-tailed t-test. In the early group, 70 per cent, and in the late group 42 per cent, of adolescents had a history of orthodontic treatment. General dentists carried out 90 per cent of the treatment in the early group and specialists every third treatment in the late group. An early start resulted in more frequent visits (P = 0.004) and a longer treatment duration (P < 0.001), while later timing resulted in an increase in the number of appliances (P < 0.001).

Reproducibility of Characteristics Assessing the Occlusion of Young Adults

The aim of the present investigation was to analyze the reproducibility in the assessment of six morphological and three functional characteristics included in a new method evaluating the occlusion in young adults. These characteristics comprised coincidence of midlines, overjet, overbite, canine relationship, crossbite, scissors bite, recurrent deviation on opening, guided lateral excursions, and discrepancy between the centric relation and the intercuspal position. The study was conducted in three stages: (1) five observers assessed the occlusions of five volunteers, (2) seven observers assessed nine volunteers, and (3) five observers assessed nine volunteers. Two calibrated orthodontists were used as references. For numerical variables, the nonparametric method for repeated measurements (Friedmans test) was used to test the significance of differences, while the proportion of agreement was calculated for categorical assessments. The results were analyzed using two precision levels: within a measurement unit/the same category and an acceptable/nonacceptable dichotomy. The magnitude of systematic differences was small and of minor clinical importance except in measurements of recurrent deviation on opening. The proportional agreement for acceptance was good in the assessment of overjet, coincidence of midlines, crossbite, scissors bite, open bite, and discrepancy between the centric relation and the intercuspal position. Moderate agreement was achieved in the assessment of overbite, canine relationship, recurrent deviation on opening, and guided lateral excursions. Among the nonacceptable cases, the agreement ranged from poor to good. The results indicated that noncalibrated observers assess categorical characteristics inconsistently.

Trends in Finnish Public Orthodontic Care from the Professionals' Perspective

The study maps out orthodontic care in Finnish municipal health centres in 2001, describes changes during the previous ten years reported by chief dental officers, and assesses the views of orthodontists on current public orthodontic services. The data were collected by questionnaires sent to all health centres and all orthodontists in Finland. Of all 0–18-year-olds, 11% were receiving orthodontic treatment with an appliance (range 2–43% among the health centres). The most frequently used appliances were headgear, quadhelix, and fixed appliances. Limited economic resources and the lack of orthodontic expertise were mentioned by the chief dental officers as factors decreasing the volume of services. The orthodontists mentioned the large regional variation and the lack of national guidelines as the most important aspects that should be improved on a national basis. To bring about improvement, they suggested increasing the number of specialist orthodontists and the delegation of orthodontic tasks to auxiliaries.

Malocclusion traits and oral health-related quality of life in Finnish adults

AIM The aim of this study was to examine the association of increased overjet, cross-bite/scissor-bite and increased overbite/open bite with oral health-related quality of life (OHRQoL) among Finnish adults using nationally representative data. METHODS Part of the data from the Health 2000 Survey, Finland, was used in this study. A total of 4711 people were included, representing adults aged ≥30 years. The outcome variable was OHRQoL severity which was measured using the 14-item Oral Health Impact Profile (OHIP-14). Three malocclusion traits (increased overjet, cross-bite/scissor-bite and increased overbite/open bite) were used as explanatory variables. Age group, marital status, education level, income, employment status, having at least one decayed tooth or periodontal pocket ≥6 mm, the number of contacting pairs of teeth, denture status and self-reported general health status were controlled for. A series of multivariable zero-Inflated Poisson (ZIP) models were used to calculate incidence rate ratios (IRR) for the nonzero scores and odds ratios (OR) of having no event. RESULTS The weighted prevalence of increased overjet was 8.4%, while it was 23.6% for cross-bite/scissor-bite and 6.7% for increased overbite/open bite. The mean (SE) OHIP-14 (OHRQoL severity) was 2.8 (0.92); the mean score was highest in the pain domain and lowest in the physical and social disability domains. The mean OHIP-14 score was higher in people with increased overjet but not significantly different in people with cross-bite/scissor-bite or with increased overbite/open bite. In multivariate ZIP models, people with increased overjet had a 10% higher OHIP-14 score than people with normal overjet. Increased overjet was associated only with the physical disability domain. Cross-bite/scissor-bite was associated only with the social disability domain, and psychological disability was associated with increased overbite/open bite. CONCLUSION People with increased overjet had significantly poorer OHRQoL than people with normal overjet in a nationally representative population of Finnish adults ≥30 years. Other malocclusion traits were not associated with OHRQoL. However, all three malocclusion traits were associated with either physical or psychological or social disability domains of the OHRQoL.

Acceptability of adolescents' occlusion in Finnish municipal health centres with differing timing of orthodontic treatment

The objective of the study was to compare the acceptability of occlusion among orthodontically treated and untreated adolescents in eight Finnish municipal health centres applying different timing of treatment. A random sample of 16- and 18-year olds (n = 2325) living in these municipalities was invited for a clinical examination, and 1109 adolescents participated. Two calibrated orthodontists blindly examined the participants for the acceptability of occlusion with the Occlusal Morphology and Function Index. The history of orthodontic treatment was elicited by questionnaire. The impact of the history and timing of treatment on the acceptability of occlusion was analysed with logistic regression analysis. The history of orthodontic treatment decreased the odds for acceptability of morphology [odds ratio (OR) = 0.719, 95 per cent confidence limit (CL), P = 0.016] and acceptability of function (OR = 0.724, 95 per cent CL, P = 0.018). The early timing of treatment increased the odds for acceptability of morphology (OR = 1.370, 95 per cent CL, P = 0.042) and of function (OR = 1.420, 95 per cent CL, P = 0.023). No substantial differences were observed in the acceptability of occlusion between the early and late timing health centres. However, the proportion of subjects with acceptable occlusion was slightly higher in the early than in the late timing group. These findings suggest that when examining the effect of timing on treatment outcome, factors other than acceptability of occlusion should be concomitantly evaluated. Consequently, in this context, the duration and cost of treatment need to be investigated.

An analysis of residual orthodontic treatment need in municipal health centres

OBJECTIVE The aim of this study was to analyse residual orthodontic treatment need in Finnish municipal health centres. SUBJECTS AND METHODS A random sample of two age groups, 16- and 18-year-olds (n = 2212), from seven municipalities was invited for a clinical examination, and 1041 adolescents participated. Two calibrated orthodontists blindly examined the participants for residual treatment need, applying the Dental Health Component (DHC) and Aesthetic Component (AC) of the Index of Orthodontic Treatment Need. Self-perceived treatment need, satisfaction with occlusal function, and dental appearance were evaluated with a questionnaire. Differences between objective and self-perceived treatment need and between treated and untreated adolescents were analysed using the chi-square test. RESULTS A total of 18.8 per cent of all adolescents had DHC grade 4 or 5 and/or AC category 8-10, indicating a definite need for treatment. In the analysis between treated and untreated adolescents, orthodontic treatment history or gender had no statistically significant association with the objectively defined need (P > 0.05). Self-perceived treatment need was reported by 9.6 per cent of adolescents. This need was more common among treated (13.9 per cent) than untreated (4.6 per cent) adolescents (P < 0.001). Among all adolescents, satisfaction with occlusal function was high, 91.3 per cent; 78.9 per cent of adolescents were satisfied with their dental appearance. The main reasons for dissatisfaction and self-perceived need were visible contact point displacements. CONCLUSIONS The observed proportion of residual orthodontic treatment need is in line with earlier findings. The high satisfaction with occlusal function reflects the applied selection criteria; orthodontic treatment of displacements causing only aesthetic concern is not prioritized.

Comparison of treatment costs and outcome in public orthodontic services in Finland

The objectives of the study were to compare the costs and outcome of orthodontic treatment in eight municipal health centres in Finland. A random sample of the age groups of 16- and 18-year-olds (n = 1109) living in these municipalities was clinically examined by two calibrated orthodontists. The acceptability of the morphology and function of the occlusion were assessed with the Occlusal Morphology and Function Index (OMFI). The data concerning previous orthodontic treatment were collected from the patient records of all subjects (n = 608) who reported previous or ongoing orthodontic treatment or who could not recall if they had received orthodontic treatment. The health centres were grouped into an early and a late timing group according to the mean age of starting the treatment. The mean age for starting orthodontic treatment was 8.0 years (SD 1.9) in the early group and 10.7 years (SD 2.3) in the late group. The visit costs and the costs of orthodontic appliances without overheads comprised the operating costs. The cost-effectiveness of orthodontic services was measured by estimating how much each health centre had to have paid for one per cent unit of acceptable morphology and acceptable function of occlusion. The mean appliance costs were higher in the late timing group and the mean visit costs higher in the early timing group. The mean operating costs per case were €720 in the early and €649 in the late timing group. However, there was a great variation within both groups. The cost of one per cent unit of acceptable morphology was the same in the two timing groups, while the cost of one per cent unit of acceptable function was lower in the early timing group. The low operating costs as such did not totally explain the better cost-effectiveness of orthodontic care. Furthermore, the cost-effectiveness was not directly connected with the timing of treatment.