A Review of Orthodontic Indices

British Society of Orthodontics in 1922 defined orthodontic specialty as, ‘Orthodontics includes the study of the growth and development of the jaws and face particularly, and the body generally as influencing the position of the teeth; the study of action and reaction of internal and external influences on the development and the prevention and correction of arrested and perverted development’. 1


A Review of Orthodontic Indices
the study of action and reaction of internal and external influences on the development and the prevention and correction of arrested and perverted development'. 1e evaluation of malocclusion is the essential component in establishing the diagnosis and treatment need of the orthodontic patient.One of the major problems in studying malocclusion is the availability of a suitable objective method for recording the occurrence and severity of orthodontic problem.Thus, orthodontic indices are used in clinical and epidemiological studies of malocclusion.The index comprise of numerical values describing the relative status of a population on a graduated scale with definite upper and lower limits, which is designed to permit comparison with other populations classified by the same criteria and methods. 2 However, none of the indices can be considered ideal for all purpose, accurate, valid and reliable for assessing the malocclusion for the priority of treatment need, allocating limited resources and assessing treatment outcomes. 3e objective of this article is to review the historical aspects of various orthodontic indices, provide their brief description and to classify them. 4Classification is expressed by a finite scale with definite upper and lower limits; running by progressive gradation from zero (absence of disease), to the Dr Alka Gupta, 1 Dr Rabindra Man Shrestha 2

Orthodontic treatment need indices
• Handicapping Labio-lingual Deviation index (HLD) (Draker, 1960, 1967)               The method for recording malocclusion can be classified into qualitative and quantitative methods. 25Qualitative method describes the occlusal features and provides descriptive classification of the dentition, however does not provide any information of the treatment need and outcome.Malocclusion symptoms are recorded in all or none manner as the studies on epidemiology of malocclusion do not define the method of measuring the variables. 26antitative methods quantify the complexity and severity of the problem rated in a scale or proportion.They are used to prioritize the need for treatment.Their use minimizes the subjectivity related to the diagnosis, outcome and complexity assessment of orthodontic treatment.

Qualitative methods of measuring malocclusion
Index Description Angle (1899)

DISCUSSION
The present article reviewed various orthodontic indices available in the literature.Classification of orthodontic indices proposed by Shaw et al 7 is the most comprehensive system found.Descriptions on indices and methods of the assessment of malocclusion mentioned in the present article are based on the opinion of respective authors.
Initially malocclusions used to be described as per the clinical features on qualitative basis, later there have been attempts to quantify them in scale and scores.The present article also attempts to categorize various orthodontic indices into qualitative and quantitative methods.
Most of the orthodontic indices use study model for analysis, however direct examination on patients and photographs have also been used in other systems.Study model serves as a patient awareness tool for the patients and allows three-dimensional analyses.Traditionally, the opinion and experience of the orthodontist are used to explain the discrepancy of the dental arches.In fact, no single classification is found to be ideal, accurate, valid and reliable for assessing the malocclusion and yet that is simple.There have been many disagreements among the authors and researchers about various indices, therefore many newer systems are developed to fulfill the shortcomings of the antecedents.Angles classification 8 is still the most widely used system in clinical and epidemiological purposes and IOTN 21 is perhaps the most accepted index for assessing treatment need.ABO Discrepancy Index 50,51 serves as the contemporary tool for complexity scores and academic evaluations.

INTRODUCTION
British Society of Orthodontics in 1922 defined orthodontic specialty as, 'Orthodontics includes the study of the growth and development of the jaws and face particularly, and the body generally as influencing the position of the teeth; 9 11 12 13 6 14 15 17 20 21 23 24 8 11 12 6jork, Krebs & Solow (1964)6• Objective registration of malocclusion symptoms based on detailed definitions.•Dataobtainedcouldbe analyzed by computers.•Primarilydevelopedforepidemiological purpose with little emphasis on treatment need.•Followingthree parts are considered: 1. Anomalies of dentition: Tooth anomalies, abnormal eruption, malalignment of individual teeth.2. Occlusal anomalies: Deviation in the positional relationship between upper and lower dental arches in sagittal, vertical and transverse plane.3. Deviations in space conditions: Spacing or crowding.

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Five major characteristics of malocclusion are represented through a Venn diagram.• Incorporates evaluation of crowding and asymmetry within the dental arches • Includes transverse, vertical and antero-posterior planes of space • Incorporates information about skeletal jaw proportions • Five-step procedure of assessing malocclusion: 1. Alignment: Ideal, crowding, spacing, mutilated.2. Profile: Mandibular prominence, mandibular recession, lip profile relative to nose and chin (convex, straight, concave).3. Crossbite: Relationship of dental arches in the transverse plane, as indicated by bucco-lingual relationship of posterior teeth.4. Angle classification: Relationship of the dental arches in the sagittal plane 5. Bite depth: Relationship of the dental arches in vertical plane, as indicated by the presence/absence of anterior/posterior open bite and posterior collapsed bite.

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Weighted measurements consist of following three parts: 1. Intra-arch deviation: Missing, crowding, rotations, spacing 2. Inter-arch deviation: Overjet, overbite, crossbite, open bite mesiodistal deviation 3. Six handicapping dentofacial deformities: Facial and oral clefts, lower lip palatal to maxillary incisors, occlusal interferences, functional jaw limitation, facial asymmetry, speech impairment 43 16 20 Links clinical and aesthetic components mathematically to produce a single score that combines physical and aesthetic aspects of occlusion, including patient perceptions.

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Tool to assess treatment need and validated instrument to evaluate the malocclusion risk in children with mixed dentition • Used to individuate not only orthodontic treatment need for children in growing age but also intervention time and treatment costs in the strength of severity of score.• Identifies 5 grades considering negative effects of malocclusion on both dento-skeletal apparatus and on psycho-social wellbeing. 22 24 Valid for the assessments of treatment need, complexity and outcome•Avoids the need to use different indices for different forms of assessment • Identification of the level of expertise needed to treat a specific case, allocation of health care resources, appropriate recognition of professionals undertaking complex care, and provision for better patient information regarding the likely complexity of the treatment.