Factors affecting the outcome of orthodontic treatment within the general dental service

The Scottish Orthodontic Peer Review project: the outcome of treatment and standard of record keeping by orthodontic specialist practitioners in Scotland

OBJECTIVES

Assess occlusal outcomes of treatment and clinical record keeping in specialist practice in Scotland.

DESIGN

A retrospective cohort study.

SETTING

Specialist practices in Scotland.

PARTICIPANTS

Specialist orthodontists in Scotland.

METHODS

Every specialist practitioner in Scotland (51) was invited to take part in the peer review project with 38 (76%) enrolled. Scotland was split into four geographical areas, and each practitioner matched with a colleague from the same area. Practitioners took one day to visit their colleague and score 30 consecutively treated NHS cases using the Peer Assessment Rating (PAR) index. They also assessed the quality of the records taken. Practitioners then swapped roles and assessed their partner's occlusal outcomes and records.

RESULTS

The mean pretreatment PAR score was 28.6 (SD 3.5). Mean posttreatment PAR score was 3.5 (SD 1.2). Mean reduction in PAR score was 25.1 (SD 3.8). Mean percentage PAR score reduction was 87.7% (SD 3.7%). Overall record keeping scores were written records 100%, study models 99.5%, Orthopantomogram radiograph 99.2%, photographs 86.3%, medical history 75% and consent 40.8%.

CONCLUSIONS

Occlusal outcomes achieved by specialist practitioners in Scotland were of a high standard. They maintained a good standard of clinical record collection in most areas examined.

Socioeconomic disparities in orthodontic treatment outcomes and expenditure on orthodontics in England's state-funded National Health Service: a retrospective observational study

Background

This study aimed to assess whether there are potential areas for efficiency improvements in the National Health Service (NHS) orthodontic service in North West England and to assess the socioeconomic status (SES)-related equity of the outcomes achieved by the NHS.

Methods

The study involved a retrospective analysis of 2008–2012 administrative data, and the study population comprised patients aged ≥10 who started NHS primary care orthodontic treatment in North West England in 2008. The proportions of treatments that were discontinued early and ended with residual need (based on post-treatment Index of Orthodontic Treatment Need [IOTN] scores that met or exceeded the NHS eligibility threshold of 3.6) and the associated NHS expenditure were calculated. In addition, the associations with SES were investigated using linear probability models.

Results

We found that 7.6% of treatments resulted in discontinuation (which was associated with an NHS annual expenditure of £2.3 m), and a further 19.4% (£5.9 m) had a missing outcome record. Furthermore, 5.2% of treatments resulted in residual need (£1.6 m), and a further 38.3% (£11.6 m) had missing IOTN data (due to either a missing outcome record or an incomplete IOTN outcome field in the record), which led to an annual NHS expenditure of £13.2 m (44% of the total expenditure) on treatments that are a potential source of inefficiency. Compared to the patients in the highest SES group, those in the lower SES groups were more likely both to discontinue treatment and to have residual need on treatment completion.

Conclusions

Substantial inefficiencies were evident in the NHS orthodontic service, with 7.6% of treatments ending in discontinuation (£2.3 m) and 5.2% ending with residual need (£1.6 m). Over a third of cases had unreported IOTN outcome scores, which highlights the need to improve the outcome monitoring systems. In addition, the SES gradients indicate inequity in the orthodontic outcomes, with children from disadvantaged communities having poorer outcomes compared to their more affluent peers.

Electronic supplementary material

The online version of this article (10.1186/s12903-017-0414-1) contains supplementary material, which is available to authorized users.

Judging orthodontic treatment complexity

Objective:

The aim of the present study was to investigate possible relations between anticipated overall treatment complexity (AOTC) of an orthodontic case and malocclusion characteristics.

Methods:

Two groups of orthodontists (groups A and B) were asked to define perceived treatment complexity (PTC) of orthodontic cases based on 16 characteristics of malocclusion by means of a questionnaire. Each question was answered on a six-point ordinal scale, with one "not applicable" option (score 0). Group A was also asked to give the AOTC of the specific case on a five-point ordinal scale. The index of orthodontic treatment need (IOTN) score of the specific cases as well as the malocclusion characteristics were assessed by one author.

Results:

There is a significant relationship between IOTN and AOTC (p< 0.0001), 22% of variability is explained by differences in IOTN. Adding objective characteristics of malocclusion to explain AOTC does not significantly increase the explained variability (p = 0.086). In judging interobserver agreement, a weighted Kappa of 0.60 for group A and 0.56 for group B was found. The weighted Kappa for agreement in AOTC equals 0.06.

Conclusion:

The relation between IOTN and AOTC was found to be significant. Moderate agreement on PTC among observers and a low level agreement regarding AOTC were found in the present study.

Patients' perceptions, treatment need, and complexity of orthodontic re-treatment

The aim of the present study was to investigate the subjective perception and objective treatment need and complexity of patients seeking orthodontic re-treatment. One hundred subjects (66 females, 34 males, age 26.7+/-8.2 years) seeking re-treatment were asked to complete a questionnaire which was constructed based on pilot interviews with 15 patients. The questions focussed on treatment experiences, retention procedures following the first course of treatment, and expectations of and motivations for re-treatment. A visual analogue scale (VAS 0-10) was used. The 're-treatment' group was matched with an untreated control group by age, gender, and the first consultation date. The study models of both groups were scored with the Index of Complexity, Outcome, and Need (ICON). Analysis of variance was used for across-time comparisons of VAS scores of patient's perception of their dental appearance, paired t-test for comparisons of the motivation VAS scores between the first treatment and re-treatment, and Mann-Whitney test for comparisons between the re-treatment and control groups. Eighty-eight patients (26.3+/-8.4 years) completed the questionnaire. After the initial treatment, 36 per cent of the patients did not have any retention measures. The mean VAS scores for dental aesthetics at the start and end of the initial treatment were 2.3+/-2.1 and 6.6+/-2.7, respectively. The scores for the present situation and expected results of re-treatment were 4.1+/-2.7 and 8.8+/-1, respectively. These scores differed significantly from each other. Seventy-nine pairs of models were matched for evaluation of treatment need and complexity. The mean ICON scores of the re-treatment group were significantly lower than the controls (45+/-21 versus 57+/-24), the aesthetic component being the main contributing factor to this difference (25+/-16 versus 36+/-18). Both groups showed a treatment need (ICON>43), with the untreated controls having a relatively higher complexity. These results indicate that patients seeking re-treatment had a good perception of dental aesthetics, strong motivation, and an objective treatment need.

The seven-year outcome of an early orthodontic treatment strategy

The benefits of early orthodontic treatment are continuously discussed, but studies are few. We examined whether definite need for orthodontic treatment could be eliminated in public health care by systematically focusing on early intervention. One age cohort living in a rural Finnish municipality (N = 85) was regularly followed from ages 8 to 15 years, and persons with malocclusions were treated according to a pre-planned protocol. Treatment need was assessed according to the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need, and treatment outcome by the Peer Assessment Rating Index (PAR). Fifty-two percent of the cohort received treatment, and definite treatment need decreased from 33% to 9%. In the treated group, the mean PAR score reduction was 63%, and 51% showed more than 70% improvement. The results suggest that an early treatment strategy may considerably reduce the need for orthodontic treatment in public health care with limited specialist resources.

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.

A comparison of the index of complexity outcome and need (ICON) with the peer assessment rating (PAR) and the index of orthodontic treatment need (IOTN)

AIM

To evaluate any relationship between ICON, IOTN and PAR. To establish whether or not ICON could replace these indices as a measure of orthodontic treatment complexity, outcome and need.

METHOD

The study models of 55 consecutively treated cases were examined and PAR, IOTN and ICON recorded.

RESULTS

The study showed significant correlations between IOTN and ICON with respect to need and PAR and ICON with respect to outcome.

CONCLUSION

It appears that ICON does reflect UK opinion and the current study provides some evidence that ICON may effectively replace PAR and IOTN as a means of determining need and outcome.

Orthodontic treatment with fixed appliances in the General Dental Service in Scotland

The records of 128 subjects treated by orthodontic specialists with fixed appliances in the General Dental Service in Scotland were randomly selected from the Scottish Dental Practice Board for analysis. The results of the study revealed that: (1) Mean post-treatment Peer Assessment Rating was 7.8 +/- 4.6 PAR points. (2) Mean reduction in PAR score was 14.9 +/- 10.6 PAR points. (3) Mean percentage reduction in PAR was 59 per cent. (4) Twenty-eight per cent of the cases were 'greatly improved', 15 per cent of the cases were made 'worse or no different'. (5) Median duration of treatment was 15 months, with a range of 2-41 months. (6) Multiple regression analysis showed that 82 per cent of the variability of PAR change could be predicted by the pretreatment PAR scores and the number of arches treated. Post-treatment PAR scores and duration of treatment could not be predicted with adequate reliability. It was concluded that although about 75 per cent of the cases were treated to at least acceptable alignment and occlusion, the modest average percentage reduction in PAR score could be explained by the low average initial PAR score and the borderline need for treatment in many cases.

A closer look at General Dental Service orthodontics in England and Wales. II: What determines appliance selection?

AIM

To elucidate factors that influence choice of appliance type in General Dental Service (GDS) orthodontics in England and Wales.

METHOD

Records were obtained for 1527 cases, representing a systematic 2 per cent sample of GDS cases completed during 1990-91. Evaluation involved Discriminant Analysis to find the most influential factors in appliance choice. Factors considered included patient and practitioner characteristics, and features of the malocclusion as assessed by Occlusal Indices.

RESULTS

Full data were available for 1217 cases. 24 per cent of treatments included use of dual- and 26 per cent single-arch fixed appliances. Appliance choice was predictable in 55 per cent of cases. Older patients, orthodontically qualified practitioners, high Peer Assessment Rating score at start, permanent dentition, lower grades of the Dental Health Component of the Index of Orthodontic Treatment Need at start, and practitioners with high gross earnings from orthodontics, all tended to be associated with more frequent use of fixed appliances.

CONCLUSIONS

Possession of a diploma or membership in orthodontics was associated with more frequent use of both dual- and single-arch fixed appliances. Better appliance selection, and thus more effective treatments in the GDS, may result from a greater availability of practitioners with formal postgraduate training in orthodontics.

A closer look at General Dental Service orthodontics in England and Wales. I: Factors influencing effectiveness

OBJECTIVE

To evaluate factors influencing effectiveness in General Dental Service (GDS) orthodontics.

DESIGN

Retrospective analysis of systematic 2% sample of GDS (England and Wales) cases.

METHOD

Records of cases were collected during 1991. Assessment involved occlusal indices and data from National Health Service forms for 1,411 cases. Multivariate analyses were used with Peer Assessment Rating Index (PAR) score at Finish as the outcome indicator.

RESULTS

Dual arch fixed appliances: achieved lower Finish PAR scores than other appliances; only 1.5% of the variance was explained, by treatment time and Dental Health Component of the Index of Orthodontic Treatment Need (DHC). Finish PAR was unaffected by Starting PAR. All other appliances: the model explained 25% of the variance for Finish PAR, which varied with Starting PAR and DHC scores. Social class had effects of little clinical significance, but the data suggested availability of orthodontic treatment was poorer in 'manual class' areas. Orthodontic qualifications, number of arches treated and mixed dentition starts had no significant effects when submitted to multivariate analysis.

CONCLUSIONS

The importance of appliance selection is reinforced: dual arch fixed appliances are generally more consistent. Lower social class areas may be poorly provided with orthodontic services.

Retrospective evaluation of the outcome of orthodontic treatment in adults

The aim of this study was the retrospective evaluation of the outcome of orthodontic treatment in consecutively treated adult patients. Of 147 adult patients, it was possible to evaluate the records of 88 patients (57 female, 31 male) before (T1) and after treatment (T2), and of 20 of these patients 3.3 years on average after completion of the retention phase (T3). During treatment planning, a nearly "ideal" result was considered attainable (ideal group) for 46 patients, and a "compromise" result (compromise group) was seen as realistic for 42. The assessment was made using the PAR (Peer Assessment Rating) index and the Aesthetic Component (AC) and Dental Health Components (DHC) of the IOTN (Index of Orthodontic Treatment Need). Average length of treatment in the ideal group was 2.4 years, i.e. nearly twice as long as in the compromise group. The PAR score was reduced by an average of 56% (T2); the reduction in the ideal group was 73%, and in the compromise group 37%. Among the 20 patients for whom at least 6 months had elapsed since completion of the retention phase, a statistically significant relapse between T2 and T3 was observed. The evaluation of overjet and overbite and, in the ideal group, of the midline and maxillary front teeth were primarily responsible for the worsening of the PAR scores between T2 and T3. According to the AC, 53 patients (60%) had moderate to definite treatment needs at the beginning of treatment. Following completion of active treatment, 69 patients (78%) no longer demonstrated treatment indications for aesthetic or psychosocial reasons. Based on the DHC, 88% of the patients were in definite or moderate need of treatment (T1); in contrast, treatment was no longer indicated in 84% at T2. In general, a marked improvement of the examined morphological parameters was observed.