Peer Assessment Rating (PAR) index outcomes for orthodontic and orthognathic surgery patients

doi:10.1016/j.bjoms.2010.03.009

British Journal of Oral and Maxillofacial Surgery

Volume 49, Issue 3, April 2011, Pages 217-220

https://doi.org/10.1016/j.bjoms.2010.03.009 Get rights and content

Abstract

The Peer Assessment Rating (PAR) index is commonly used to evaluate occlusal outcomes after orthodontic treatment. We compared the PAR outcomes of 40 consecutively treated orthodontic patients and 40 orthognathic patients to evaluate the standard of care given. A patient-centred questionnaire was used to examine patients’ perceptions of the benefits of orthognathic treatment. PAR scores of orthodontic and orthognathic patients improved by a mean of 77% and 74%, respectively, after treatment indicating that excellent to good occlusal results were achieved for both groups. A high quality occlusal outcome is important for all patients as good intercuspation at the end of treatment is thought to improve stability. Most orthognathic patients reported improvements in their dental and facial appearance and thought that the treatment had been beneficial.

Introduction

Clinicians have a duty to ensure that systems are in place to produce acceptable treatment outcomes. Clinical outcomes after orthodontic treatment are often measured using occlusal indices to establish the overall standard of care. Occlusal indices are measured from study models taken before and after completion of treatment.

The Peer Assessment Rating (PAR) index is commonly used and has validity and reproducibility.1, 2, 3 It is a useful tool that can be used to audit the outcomes of orthodontic treatment objectively, and has been used extensively in Europe.4, 5, 6, 7, 8 It is a suitable index for the assessment of outcome and improvement in patients treated with a combined orthodontic and orthognathic approach.⁹

PAR scores are measured from plaster study models taken before and after treatment to establish a mean reduction in the score; a mean improvement of more than 70% represents a very high standard of treatment. Ideally the number of patients in the “worse, or no improvement” category should be less than 5%.¹

Patient-centred questionnaires can also be used to assess the patient's experience of treatment. Travess et al.¹⁰ developed a validated questionnaire to examine patients’ perceptions of the process, and the outcome of combined orthodontic and orthognathic treatment. This questionnaire was used in 13 hospitals in the south west region of the UK.11, 12

The primary aim of this prospective service evaluation was to assess occlusal outcomes using the PAR index in 40 consecutively treated orthodontic and 40 orthognathic patients. The secondary aim was to assess the patients’ perceptions of the benefits of orthognathic treatment.

Section snippets

Methods

Forty consecutive patients who had had orthodontic treatment to correct their malocclusion, and 40 consecutively treated patients with dentofacial deformities who had had a combination of orthodontic and surgical treatment were identified within our local maxillofacial unit. Selection commenced in January 2007. All patients in the orthognathic group had rigid internal fixation. Orthodontic treatment was carried out by five clinicians within the department, and the operations by one of three

Results

All 40 sets of study models (before and after treatment) were available for the orthodontic group, and they were PAR scored. One set of models from the orthognathic group (before treatment) was not available, so only 39 full sets were PAR scored.

A sample of 40 sets of study models (20 orthodontic, 20 orthognathic) were re-examined and reproducibility was calculated with the kappa statistic. Reliability within and between examiners was 0.84 (95% CI, 0.70–0.97), which indicated good reliability.

Discussion

The mean percentage improvement in PAR scores for orthodontic and orthognathic treatment were 77% and 74%, respectively, which indicates excellent to good occlusal results for both groups. The better improvement in the orthodontic group does not agree with Richmond et al.¹ who reported a higher reduction in orthognathic surgical cases than in orthodontic cases. Although the overall mean percentage reduction in the PAR scores was similar for both groups, the mean scores before treatment were

Acknowledgements

We thank John Endean, laboratory technician, and Mr. Stephen Robinson, consultant orthodontist for their input into this study.

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Cited by (19)

Did the coronavirus disease 2019 pandemic affect orthodontic treatment outcomes? A clinical evaluation using the objective grading system and Peer Assessment Rating index
2022, American Journal of Orthodontics and Dentofacial Orthopedics
Citation Excerpt :
This study found no differences in treatment duration between the groups, measured from the time appliances were placed to the time removed (Table I). Factors that may influence the treatment duration include age, gender, the severity of malocclusion, extractions, and clinician experience.36 This study shows that PAR reduction or total OGS score were not associated with treatment duration even though group 2 had significantly fewer and irregular appointments and a significantly less total number of appointments, raising the question of whether some control intervals can be partly replaced by teleorthodontics (Table I).
This study aimed to compare the treatment outcome of patients whose orthodontic treatment was completed before or during the coronavirus disease 2019 pandemic.
Pretreatment and posttreatment models of 100 patients treated with fixed orthodontic appliances were evaluated using the peer assessment rating (PAR) index. Posttreatment models and panoramic radiographs were measured and scored with the objective grading system (OGS). All patients had their treatment plans before the coronavirus disease 2019 pandemic, but the orthodontic treatment finishing date was before (prepandemic: group 1, n = 50) or during (pandemic: group 2, n = 50) the pandemic. Intergroup comparisons were tested with an independent samples t test or Mann-Whitney U test. Chi-square test statistics and Fisher exact test were used to compare categorical variables.
Significant higher posttreatment weighted maxillary alignment score was found in group 2. However, no significant difference was found between the groups concerning the mean total weighted PAR reduction (29.8 ± 9.9 vs 25.6 ± 8.7) and posttreatment total weighted PAR scores (1 vs 2). The PAR index score improvement (%) was similar between the groups (93.7 ± 7.1 vs 89.9 ± 13.0). No statistically significant difference was found between the groups for the total OGS score (32 vs 33). A lower score for marginal ridge height (4 vs 3) and a higher score for buccolingual inclination (7 vs 11), and a lower score for occlusal relationship (3 vs 1) were found in group 2. Canceled appointments (1.1 ± 0.7 vs 4.8 ± 1.6) and the number of missed appointments (0.6 ± 0.5 vs 1.1 ± 0.8) were statistically higher in group 2, whereas the total number of appointments (27.3 ± 8.8 vs 21.8 ± 5.4) were statistically less. The treatment duration was comparable in both groups.
Reduced and irregular appointments during the pandemic resulted in significantly higher posttreatment weighted maxillary alignment and worsening of the buccolingual inclination. However, the PAR score improvement, total OGS score, and treatment duration were not affected.
Variation in UK Deanery publication rates in the British Journal of Oral and Maxillofacial Surgery: where are the current 'hot spots'?
2021, British Journal of Oral and Maxillofacial Surgery
Publication in peer-reviewed journals is often seen as a cornerstone of the academic and clinical career within medicine and surgery. As one of the largest circulations in oral and maxillofacial surgery, the British Journal of Oral and Maxillofacial Surgery (BJOMS) offers trainees and consultants the opportunity to disseminate valuable information worldwide. The aim of this paper is to investigate the variation in publication rates of U.K. authors based upon their Deanery in order to identify potential hotspots. All volumes of BJOMS between 2011 and 2019 were hand searched to identify full articles authored by authors in U.K., these were categorised by Deanery and allocated a theme within OMFS. The results demonstrate that, of the 378 full length articles, over 30% of these were from two Deaneries: London and North West (West). Oncology, OMFS training and education, and craniofacial trauma were the three most common themes of publication amounting to 51.5% of total publications. There has been an unfortunate decrease in publications from U.K. Deaneries of almost 30% from 2011 to 2019 which begs the question of whether fewer publications are being accepted or if rates of submission have reduced.
Effectiveness of lingual versus labial fixed appliances in adults according to the Peer Assessment Rating index
2019, American Journal of Orthodontics and Dentofacial Orthopedics
Citation Excerpt :
The results of the present study are consistent with those published by Luther et al.25 Another study26 concluded that age differences do not seem to play a role in the duration of the treatment, provided that patients are in the permanent dentition. As indicated by Ponduri et al,4 Dyken et al.9 reported that a high PAR score before treatment and a large percentage reduction in the score were significantly associated with long durations of treatment. However, the occlusal index scores after treatment were not associated with duration.
The purpose of this study was to compare the effectiveness of lingual treatment and labial fixed appliances in the treatment of adult orthodontic patients.
We conducted a retrospective study of 72 patients. The Peer Assessment Rating (PAR) index was measured at the start (T0) and end (T1) of treatment. Significant differences between treatment means were determined by means of analysis of variancewith the Bonferroni correction or with the use of Fisher exact test.
The lingual group had a mean pretreatment age of 28.6 ± 6.7 years, and the labial group had a pretreatment age of 26.6 ± 9.5 years. This difference was statistically not significant. The mean pre- and posttreatment PAR scores in the labial group were 22.9 ± 6.2 and 2.1 ± 2.3, respectively, and the mean pre- and posttreatment PAR scores in the lingual group were 26.5 ± 8.3 and 2.3 ± 2.5. There were no significant differences between the treatment groups.
Lingual and labial appliances produced similar reductions in PAR scores. There was no difference in the posttreatment PAR scores between the lingual and labial treatment groups. Further studies involving larger sample sizes and longer follow-up periods are required to confirm the results obtained.
Patient expectations and satisfaction following orthognathic surgery
2019, International Journal of Oral and Maxillofacial Surgery
Citation Excerpt :
Ponduri et al. assessed whether treatment would improve the occlusal relationship in 40 patients who had orthodontic procedures and 40 patients who had orthognathic procedures. They found that all participants reported improvements in aesthetics or function, or both12. This is in keeping with the present study results, with 90.7% reporting improved aesthetics following treatment.
Orthognathic surgery aims to correct dentoskeletal and facial discrepancies. Treatment usually requires a minimum of 18 months, necessitating that patients are adequately satisfied with the treatment provided. This study aimed to assess the determinants of patient satisfaction following treatment. One hundred and eighteen patients who had undergone orthognathic surgery were included prospectively. All participants completed a questionnaire regarding their reasons for undergoing treatment, treatment logistics, treatment outcomes, and satisfaction throughout their journey. Most patients were ‘very satisfied’ (71.2%) or ‘satisfied’ (19.5%) with the overall treatment. The majority wished to improve their smile (78.0%); post-treatment, 89.0% of patients reported an improved smile. Almost half of the patients (46.6%) stayed in hospital for only one night, and 41.5% took over 4 weeks off work or school post-surgery. People with postoperative breathing difficulties spent more days in hospital (P = 0.021), but importantly, the duration of hospital stay did not differ between maxillary advancement, bilateral sagittal split osteotomy, and bimaxillary surgery (P = 0.78). In conclusion, patient satisfaction was high following orthognathic treatment. The results highlight areas for improvement, such as information delivery to the patient throughout the treatment journey, and show that the presence of ongoing problems is an important predictor of patient satisfaction.
Assessing the outcome of orthognathic surgery by three-dimensional soft tissue analysis
2018, International Journal of Oral and Maxillofacial Surgery
Studies of orthognathic surgery often focus on pre-surgical versus post-surgical changes in facial shape. In contrast, this study provides an innovative comparison between post-surgical and control shape. Forty orthognathic surgery patients were included, who underwent three different types of surgical correction: Le Fort I maxillary advancement, bilateral sagittal split mandibular advancement, and bimaxillary advancement surgery. Control facial images were captured from volunteers from local communities in Glasgow, with patterns of age, sex, and ethnic background that matched those of the surgical patients. Facial models were fitted and Procrustes registration and principal components analysis used to allow quantitative analysis, including the comparison of group mean shape and mean asymmetry. The primary characteristic of the difference in shape was found to be residual mandibular prognathism in the group of female patients who underwent Le Fort I maxillary advancement. Individual cases were assessed against this type of shape difference, using a quantitative scale to aid clinical audit. Analysis of the combined surgical groups provided strong evidence that surgery reduces asymmetry in some parts of the face such as the upper lip region. No evidence was found that mean asymmetry in post-surgical patients is greater than that in controls.
Review of orthognathic surgery and related paper spublished in the British Journal of Oral and Maxillofacial Surgery 2011-2012
2015, British Journal of Oral and Maxillofacial Surgery
Citation Excerpt :
Ponduri et al. used the Peer Assessment Rating (PAR) index to assess the effect of treatment to improve the occlusal relation in 40 patients who had orthodontic, and 40 who had orthognathic procedures. Outcome was reported as “excellent to good” in both groups, and all participants reported improvement in aesthetics or function, or both.16 In a study of 27 patients undergoing bimaxillary osteotomy, Edler et al. showed that standardised clinical photography and specialised graphics software can be used as a valid quantitative outcome tool to compare interalar width before and after operation, and to assess mandibular asymmetry.17
This review summarises all orthognathic and related papers published between January 2011 and December 2012 in the British Journal of Oral and Maxillofacial Surgery (BJOMS). A total of 36 articles were published, a high proportion of which (78%) were full-length papers. The remainder consisted of short communications and technical notes. The topics included operative planning and postoperative outcomes, and there was a strong focus on distraction osteogenesis. There were fewer orthognathic articles published in BJOMS than articles on other subspecialties such as trauma or head and neck oncology. Only 8 (29%) of the full-length articles were prospective studies or randomised trials, which highlights a need for well-designed clinical studies in orthognathic research.

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Peer Assessment Rating (PAR) index outcomes for orthodontic and orthognathic surgery patients

Abstract

Introduction

Section snippets

Methods

Results

Discussion

Acknowledgements

Am J Orthod Dentofacial Orthop

Am J Orthod Dentofacial Orthop

Am J Orthod Dentofacial Orthop

Br J Oral Maxillofac Surg

Br J Oral Maxillofac Surg

Br J Oral Maxillofac Surg

The development of the PAR index (Peer Assessment Rating): reliability and validity

Eur J Orthod

The use of occlusal indices in assessing the provision of orthodontic treatment by the hospital orthodontic service of England and Wales

Br J Orthod

Orthodontic treatment standards in Norway

Eur J Orthod