The reliability and validity of the Index of Complexity, Outcome and Need for determining treatment need in Dutch orthodontic practice

The Index of Complexity, Outcome and Need (ICON), based on international opinion, has been proposed as a multipurpose occlusal index. The aim of this study was to validate the ICON for treatment need in the Netherlands by relating it to Dutch orthodontic opinion. Furthermore, the reliability of this index was explored, for both a calibrated orthodontist and non-calibrated orthodontists. A sample of 102 patients was chosen which represented the actual distribution of severity of malocclusion experienced by orthodontists in every day practice. The ICON was scored, based on complete patients records of those 102 patients, by an examiner calibrated in the use of this index. The results were compared with the opinion about treatment need of seven Dutch orthodontists - the 'gold standard'. Nine non-calibrated orthodontists also scored the ICON for 49 patients. The intra-examiner agreement of both the non-calibrated and the calibrated orthodontists was moderate to high [0.52-0.86 and 0.89, respectively, measured with the Intraclass Correlation Coefficient (ICC)]. The inter-examiner agreement of the ICON score of the nine orthodontists was moderate measured with the single estimate of the ICC (0.60), and high measured with the average estimate (0.93). Spearman's correlation coefficient between the ICON score (calibrated) and the gold standard was sufficient: 0.78. The sensitivity and specificity were 1 and 0.36, respectively. The best compromise between sensitivity and specificity was at a cut-off point of 52, instead of the international ICON cut-off point of 43. There was a significant difference in ICON score between the non-calibrated orthodontists and the calibrated orthodontist, mainly based on the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN). It can be concluded that the ICON needs to be adjusted when used to determine treatment need in the Dutch orthodontic population.     

Effectiveness of training dental students in two occlusal indices

The purpose of this study was to evaluate the ability of students in a U.S. dental school to learn and apply two indices of orthodontic need: the Index of Orthodontic Treatment Need (IOTN) and the Index of Complexity, Outcome, and Need (ICON). Dental students were randomly selected and separated into three groups: control, IOTN, and ICON. Each evaluated thirty casts that had previously been evaluated by a panel of thirteen orthodontists to develop a gold standard of orthodontic treatment need for these casts. Students re-evaluated the same thirty casts after IOTN and ICON training for their own group, while the control group did not receive any training. Logistic regression of pre- and post-training agreement with the gold standard was calculated for each group to create a clear quadratic relationship. Significant differences were not found between pre- and post-training evaluation for either the IOTN or the ICON groups as compared to the control. However, the IOTN group did show more improvement when compared with the ICON group. This study demonstrates that the use of the IOTN index improved assessment in predoctoral dental students to determine orthodontic treatment need.     

Concern for dental appearance among Norwegian young adults in region with low uptake of orthodontic treatment

Abstract – The purpose of the present study was to examine orthodontic concern among orthodontically untreated young adults living in an area where the relative number of children receiving treatment was only 15–20% and to compare orthodontic concern among these individuals with that of untreated persons from an area with a higher treatment frequency. All the subjects were clinically examined and impressions for dental study casts, radiographs and photographs were taken. The subject's occlusion was classified according to two methods: 1) allocation to one of four groups according to the national Need for Orthodontic Treatment Index (NOTI), and 2) allocation to one of three groups according to presence or absence of six Anterior Occlusal Traits (AOT). Frequencies of NOTI scores demonstrated that in the study group more individuals were in need of treatment relative to the comparison group. Reported concern was at the same level in both groups, and significantly related to NOTI and AOT scores. The individuals in the area with the low treatment frequency were generally less aware of their anterior traits compared to the individuals in the area with a higher treatment frequency. The results indicated that a long-term low uptake of orthodontic treatment among children in the particular area was not accompanied by a similar increase in concern about own dental appearance in early adulthood.     

Attitudes to malocclusion among 18- and 35-year-old Norwegians

Abstract Knowledge about age-related changes in attitudes to dental appearance and orthodontic treatment may guide the orthodontist in educating and providing advice to potential patients and their parents. The purpose of the present study was to compare attitudes to malocclusion in groups of young and middle-aged adults from populations having been exposed to similar provision of care. The material comprised samples of orthodontically untreated 18-yr-olds (n=50) and 35-yr-olds (n=73) from Oslo, Norway. From a clinical examination, radiographs, and measurements on dental study casts, the subjects were classified according to the Need for Orthodontic Treatment Index (NOTI) used by the Norwegian Health Insurance System. Satisfaction with dental appearance and desire for orthodontic treatment were investigated using questionnaires. The 35-yr-olds exhibited significantly more malocclusion compared to the 18-yr-olds (P<0.01). Among subjects classified to have obvious need for orthodontic treatment, 54% and 21% expressed dissatisfaction at ages 18 yr and 35 yr, respectively, indicating a lower level of concern for malocclusion in the older age group.     

The planning, contracting and monitoring of orthodontic services, and the use of the IOTN index: a survey of consultants in dental public health in the United Kingdom

OBJECTIVES: To establish which factors are used in planning, contracting and monitoring orthodontic services in the United Kingdom. In addition, the study investigated the value of the Index of Orthodontic Treatment Need (IOTN) as an instrument for planning orthodontic provision. METHODS: A structured questionnaire was sent to all consultants in dental public health in the United Kingdom. RESULTS: Over 80% of the respondents used the Index of Orthodontic Treatment Need (IOTN) as an instrument for planning, contracting and monitoring orthodontic services. Seventy per cent of these consultants regarded the IOTN index as a useful or very useful instrument. The main strength reported was that the IOTN index allows prioritisation (25.0%). The main weakness reported was that the index does not assess complexity (70.5%). CONCLUSIONS: Consultants in dental public health perceived the IOTN as a useful tool for planning orthodontic provision despite some shortcomings.     

An insight into four orthodontic treatment need indices

Occlusal indices have been introduced and used to rank or categorize the occlusion. According to Dr. William Shaw and colleagues (1995), there are five types of occlusal indices, diagnostic, epidemiologic, orthodontic treatment need, orthodontic treatment outcome, and treatment complexity indices. Orthodontic treatment need indices are used to rank the malocclusion. They were devised to minimize the subjectivity associated with the diagnosis, referral and complexity assessment of malocclusion. Some are also multifunctional and used to assess the outcome of orthodontic treatment. The overall aim of the present article is to provide an overview on four commonly used American and European orthodontic treatment need indices, review their modifications, advantages, and limitations. These indices are the Index of Orthodontic Treatment Need (IOTN), the Dental Aesthetic Index (DAI), the Handicapping Labio-Lingual Deviation index (HLD), and the Index of Complexity, Outcome and Need (ICON).     

A validation study of three indexes of orthodontic treatment need in the United States

Abstract The purpose of this study was to compare the reliability and validity of three occlusal indexes of orthodontic treatment need in predicting the opinion of treatment need of a panel of 18 orthodontists. A set of 160 study casts representing all types of malocclusion was used. The casts were scored with the following occlusal indexes: the Index of Orthodontic Treatment Need (IOTN), the Handicapping Labio-Lingual Deviations index (HLD), and the Handicapping Malocclusion Assessment Record (HMAR modified). The diagnostic accuracy or validity of each index was calculated using the mean opinion of the orthodontic raters as a “gold standard”. Receiver Operating Characteristic curves were plotted for each index. The overall diagnostic accuracy, as determined by percent area under the curve, was similar for each index: IOTN 98.6%; HLD 96.1%; HMAR 96.6%. The score optimizing the sensitivity and specificity relationship for each index was as follows: IOTN (dental health component) 4; HLD 13; HMAR 12. These results indicate that the three occlusal indexes provided valuable information for determining orthodontic treatment need.     

Morphological, functional and aesthetic criteria of acceptable mature occlusion.

At present, there are no generally accepted criteria that could easily be applied to the evaluation of occlusal acceptability in clinical examinations at population level. The present study analyses the opinions of Finnish orthodontists and general practitioners on the characteristics required for acceptable occlusion in the full permanent dentition. A questionnaire was sent to all 37 health centres where at least one orthodontist was employed, 31 regionally comparable health centres without an orthodontist, 12 private orthodontists, and 13 orthodontists working at university dental clinics. Seventy-four orthodontists returned the questionnaire giving a response rate of 80 per cent. They were asked to give their views on the importance of morphology, function, long-term stability, and dental appearance as elements of acceptable occlusion. They were also encouraged to indicate other significant characteristics and requested to assess the relative significance of these features. In general, the respondents expressed the need to assess morphological, functional and aesthetic aspects of occlusion as a whole. Good function, rather than morphology, was considered to be the most important feature of an acceptable occlusion, with a relative significance of 40 per cent (range 20-90 per cent). According to the respondents, the acceptability of occlusion is determined not only by morphological features, but also by the functional status and long-term stability, as well as by the patient's opinion of the dental appearance.     

The reliability of the Index of Orthodontic Treatment Need over time

The aim of this investigation was to establish whether the Index of Orthodontic Treatment Need is reliable over time between the ages of 11 and 19 years. It consisted of a longitudinal sample of 314 11- and 15-year-old and 142 19-year-old subjects who had not received orthodontic treatment or extractions. The changes in the aesthetic component (AC) and the dental health component (DHC) of the Index of Orthodontic Treatment Need (IOTN) were measured between the ages of 11 and 19 years. The results suggested that the dental health component of IOTN was reliable over time between the ages of 11-19 years despite temporal changes in the separate occlusal traits that comprise the index. The aesthetic component of IOTN tended to show an improvement over time. The Index of Orthodontic Treatment Need is a reliable index over time when taking into account occlusal changes that are occurring during the 11-19-year age range. The study provides some reassurance to clinicians that an IOTN grading at age 11 years is unlikely to change by the time the patient is 19 years. Refereed Scientific Paper     

Orthodontic treatment need in a 12-year-old population in the Western Sahara

The aim of this study was to establish orthodontic treatment need according to the Dental Aesthetic Index (DAI) and Aesthetic Component (AC) and Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN) and to determine its association with gender among Saharan schoolchildren. The study was carried out in accordance with World Health Organization (WHO) recommendations for oral health surveys at 12 years of age. The sample comprised 248 Sahrawi children (135 girls and 113 boys) living in refugee camps in Tindouf, Algeria. None of the children had previously received any orthodontic treatment. A chi-square test was used to analyse the IOTN results by gender, and a Student's t-test was employed for the DAI results. The mean DAI was 23.32 with a standard deviation of 6.05, 4 percent with a very severe and 9.2 per cent with severe malocclusion. Orthodontic treatment need was 16.1 and 2.0 percent, respectively, according to grades 4 and 5 of the IOTN DHC, 13.7 percent according to the IOTN AC, and 28.6 percent according to the modified IOTN (IOTN DHC grades 4-5 and/or IOTN AC grades 8-10). There were no statistically significant differences by gender. The orthodontic treatment need of Western Saharan schoolchildren is similar to that reported by many recent studies in European and in Sub-Saharan countries.     

上海地区青少年正畸治疗需要的调查研究

目的:调查上海地区青少年人群的正畸治疗需要及自身美学评价。方法:随机抽取上海地区11～13岁青少年686例(男355例,女331例),由正畸专科医师采用正畸治疗需要指数(index of orthodontic treatment need,IOTN)评定受试者正畸治疗需要。IOTN包括学(dental health component,DHC)及美学(aesthetic component,AC)2部分。同时采用IOTN的美学部分让受试者对自身美观程度进行评价(self-perceived aesthetic component,SAC)。采用描述性统计及卡方检验对调查结果进行统计分析。结果:DHC评分显示26.0%的受试者明确需要正畸治疗,19.8%的受试者为临界病例;AC评分显示5.5%的受试者明确需要正畸治疗,31.7%为临界病例;SAC评分显示1.7%的受试者明确需要正畸治疗,6.4%为临界病例。在明确需要正畸治疗的受试者中,最常见的特征是严重接触点异常(>4 mm)。DHC与AC在评价治疗需要时77.8%结果一致,AC与SAC在评价治疗需要时65.0%结果一致。结论:将近一半的青少年人群明确需要正畸治疗或为临界病例,受试者在进行自身美观程度评价有从轻的倾向。     

Modified IOTN: an orthodontic treatment need index for use in oral health surveys

This paper reports the results of a study of the reliability of a modified version of the Index of Orthodontic Treatment Need (IOTN) for use in oral health surveys. Twelve non-specialist dental examiners were trained in the use of the Modified IOTN using a standardised teaching protocol lasting approximately 1.5 hours. Following a school-based calibration exercise it was found that nearly all the examiners achieved either good or excellent agreement (mean Kappa=0.74). The average sensitivity and specificity scores were 0.90 and 0.84, respectively. The Modified IOTN appears to overcome the training and reliability problems that often accompany the use of orthodontic indices by non-specialists in oral health surveys.     

Efficacy of training dental students in the index of orthodontic treatment need.

Orthodontic studies over several decades have found generally inconsistent opinions among dentists when evaluating orthodontic treatment need. There has also been recent concern that dental school education does not sufficiently prepare dentists to diagnose malocclusion and make appropriate referrals of potential orthodontic patients. The purpose of this study was to investigate the efficacy of using the index of orthodontic treatment need (IOTN) as a tool to improve dental students' ability to assess orthodontic treatment need. Fourth-year dental students were randomly divided into control, sham-control, and experimental groups stratified for mean grade point average. On 2 occasions, the subjects evaluated 30 orthodontic study models with a gold standard previously established by an expert panel of 15 orthodontists for orthodontic treatment need. The experimental group reevaluated the models after IOTN instruction. Kappa statistics, sensitivity, and specificity were calculated for each subject. Analysis of covariance (ANCOVA) showed that the experimental group had significantly higher agreement with the expert panel after IOTN training than did either control group. IOTN is a promising teaching aid for improving educational outcomes for orthodontic referral.     

Assessing malocclusion--the time factor.

Abstract

Assessment of occlusal status for orthodontic purposes may be undertaken by subjective assessment or by means of an index of occlusion. The assessment method should be reproducible and should achieve the intended outcomes. This study investigated another possible modifying factor--performance over time. Photographs and dental casts of 45 subjects at 12 years of age were compared with follow-up records at 16 years of age. No orthodontic intervention had occurred during the 4 years. Subjective severity assessments and Aesthetic Component (AC) scores of the Index of Treatment Need (IOTN) for first and second series records were made by four orthodontists. Scores of the Dental Aesthetic Index (DAI) and Dental Health Component (DHC) of the IOTN were made by one of the authors. Implications for hypothetical decisions to treat were considered. There was a significant reduction in the subjective severity and DAI scores across the whole sample and in the mixed dentition subgroup. There was a non-significant reduction in the AC (IOTN) scores across the whole samples, but there was a significant reduction in the AC (IOTN) scores in the mixed dentition subgroup. The DHC (IOTN) categorisations proved to be more stable over the period of study.     

Associations between orthodontic treatment need and oral health‐related quality of life among young adults: does it depend on how you assess them?

Liu Z, McGrath C, Hägg U. Associations between orthodontic treatment need and oral health‐related quality of life among young adults: does it depend on how you assess them? Community Dent Oral Epidemiol 2011; 39: 137–144. © 2011 John Wiley & Sons A/S Abstract – Objective: To determine the association between orthodontic treatment need (OTN) and oral health‐related quality of life (OHRQoL). Methods: A cross‐sectional study involving 273 young adults seeking orthodontic care. OHRQoL was assessed by the short‐form Oral Health Impact Profile (OHIP‐14) and United Kingdom oral health‐related quality of life measure (OHQoL‐UK). Study casts were assessed for OTN by: Dental Aesthetic Index (DAI), Index of Orthodontic Treatment Need (IOTN)‐Aesthetic Component (IOTN‐AC) and Dental Health Component (IOTN‐DHC) and Index of Complexity, Outcome and Need (ICON). Variations in OHIP‐14 and OHQoL‐UK were determined with respect to OTN, and the magnitude of differences was calculated (effect size: ES). Results: There were significant but weak correlations between occlusal indices scores and OHIP‐14 scores (P < 0.05, r < 0.3) and between occlusal indices scores and OHQoL‐UK scores (P < 0.05, r < 0.4). The magnitude of the statistical difference in OHQoL‐UK scores was moderate to large with respect to OTN (ES: 0.36–0.87) and largest when DHC (ES = 0.87) and ICON (ES = 0.74) were used. The magnitude of the statistical difference in OHIP‐14 scores was relatively lower (ES: 0.21–0.69), but also greatest when DHC and ICON were used to determine OTN (ES 0.69 and 0.50, respectively). Conclusion: Orthodontic treatment need was associated with OHRQoL. The magnitude of the statistical difference between those with and without an orthodontic treatment need was larger when OHRQoL was assessed using OHQoL‐UK compared to OHIP‐14. DHC and ICON were more useful indices in identifying greater differences in OHRQoL with respect to orthodontic treatment need.     

A cultural comparison of treatment need

The aims of this study were two-fold. First to compare the perceptions of African dental aesthetics as determined by a panel of black African Senegalese and French Caucasian judges, and second to compare the sensitivity and specificity of both components of the Index of Orthodontic Treatment Need (IOTN) and the Index of Complexity, Outcome and Need (ICON) in relation to the opinions of African and Caucasian judges. Ninety-eight colour digital dental images of black adolescents and adults were scored for attractiveness on a 100 mm visual analogue scale (VAS) by 45 Caucasian and 41 black African judges. In addition the judges were asked to classify the level of treatment need. Both components of the IOTN and ICON were recorded for the 98 cases. The results indicated that Caucasian judges perceived the majority of images to be less attractive than African judges. African and Caucasian judges showed similar levels in the estimation of treatment need. The aesthetic component (AC) of the IOTN and ICON showed similar levels of sensitivity. Taking all factors into account, it would appear that the ICON is marginally better at identifying those individuals who are perceived to need orthodontic treatment.     

Socio-economic status and orthodontic treatment need

Abstract– Objectives: This study aimed to examine the relationship between socio-economic status and both normatively assessed and self perceived need for orthodontic treatment. Methods: More than six thousand 14-year-old children were assessed for orthodontic treatment by trained and calibrated examiners. The Index of Orthodontic Treatment Need was the measuring instrument along with a questionnaire which asked: “Do you think your teeth need straightening?”Results: Normative need for orthodontic treatment (IOTN > 3) was more common amongst deprived children than among their affluent counterparts. The same was found for perceived need. However, the children who wanted treatment were not necessarily those who needed it and vice versa. Conclusions: Socio-economic status affects normatively measured orthodontic treatment need through, as yet, undefined mechanisms. It also affects a person's perception of need for orthodontic treatment, but these two associations are separate. The mismatch of need and desire for treatment is a problem for orthodontists.     

儿童错畸形对其父母生活质量的影响

目的:研究儿童的错(牙合)畸形对其父母生活质量的影响和两者间的关系.方法:从正畸科临床就诊病人中选择155名儿童患者,对其错(牙合)畸形的严重程度采用常用的正畸治疗需要指数(IOTN-AC和DHC、ICON和DAI)进行评估;另外,儿童的家长填写一份关于儿童口腔健康对父母生活质量影响的问卷(family impact scale-FIS).结果:儿童的错(牙合)畸形会影响父母的生活质量,包括日常活动和家长情绪;需要正畸治疗的儿童的FIS分数明显高于不需要正畸治疗者.统计效应最小0.07、最大0.42.多元回归结果显示FIS分数与是否需要正畸治疗、儿童性别、家长文化程度、家长性别没有关系.结论:儿童错(牙合)畸形会影响家长的生活质量,但受影响程度与儿童错(牙合)畸形的严重程度相关性不大.     

The need for treatment and satisfaction with dental appearance among young Finnish adults with and without a history of orthodontic treatment.

The aim of this investigation was to evaluate orthodontic treatment need and patient satisfaction among young adults living in a city where free-of-charge orthodontic treatment was provided. A total of 281 18- to 19-year-old subjects randomly selected from the population register of the city of Vantaa took part in the study. The drop-out rate was 30%. Treatment need was clinically assessed according to the Index of Orthodontic Treatment Need (IOTN), consisting of a Dental Health Component (DHC) and an Aesthetic Component (AC). Information on previous orthodontic treatment was based on the patient records. Satisfaction of the subjects with their dental appearance and with the orthodontic treatment received was obtained using a questionnaire. The rate of orthodontic treatment among the subjects was 46% (54% for the females and 37% for the males, p < 0.05). 4% had discontinued treatment. A definite need for treatment (DHC 4 to 5/AC 8 to 10) was assessed in 15% of the subjects, and borderline/moderate need (DHC 3/AC 5 to 7) in 36%. No difference in IOTN scores between the treated and untreated subjects was found. Females had significantly more often no treatment need (DHC 1 to 2/AC 1 to 4) compared with males (p < 0.05). The majority of subjects (89%) reported that they were very or quite satisfied with their dental appearance. The odds of being satisfied were significantly higher for the treated subjects (OR = 2.71, p < 0.05) and lower for those at the non-attractive end of the AC scale (OR = 0.14, p < 0.01). Neither gender nor DHC grade significantly affected the odds of being satisfied among the subjects. The results indicate that the majority of young adults in this study were satisfied with their dental appearance regardless of objective treatment need of various degrees. The high treatment rate in relation to unnoticed treatment need calls for reevaluation of priorities in patient selection.     

The orthodontic–periodontic interrelationship in integrated treatment challenges: a systematic review

Summary Orthodontic treatment aims at providing an acceptable functional and aesthetic occlusion with appropriate tooth movements. These movements are strongly related to interactions of teeth with their supportive periodontal tissues. In recent years, because of the increased number of adult patients seeking orthodontic treatment, orthodontists frequently face patients with periodontal problems. Aesthetic considerations, like uneven gingival margins or functional problems resulting from inflammatory periodontal diseases should be considered in orthodontic treatment planning. Furthermore, in cases with severe periodontitis, orthodontics may improve the possibilities of saving and restoring a deteriorated dentition. In modern clinical practice, the contribution of the orthodontist, the periodontist and the general dentist is essential for optimized treatment outcomes. The purpose of this systematic review is to highlight the relationship between orthodontics and periodontics in clinical practice and to improve the level of cooperation between dental practitioners. Potentials and limitations that derive from the interdisciplinary approach of complex orthodontic–periodontal clinical problems are discussed.