IOTN.pdf

IOTN (Index of Orthodontic Treatment Need) The purpose of the index was to Help determine the likely impact of a malocclusion on an individual’s dental health and psychosocial well-being. It is compromised of two elements: 1) Dental Health Component 2) Aesthetic Compo...

IOTN (Index of Orthodontic Treatment Need) The purpose of the index was to Help determine the likely impact of a malocclusion on an individual’s dental health and psychosocial well-being. It is compromised of two elements: 1) Dental Health Component 2) Aesthetic Component Components of the IOTN 1) Dental Health Component (DHC) The single worst feature of a malocclusion is noted (the index is not cumulative) and categorized into one of ve grades re ecting need for treatment: - Grade 1 — no need - Grade 4 — great need - Grade 2 — little need - Grade 5 — very great need - Grade 3 — moderate need 2) Aesthetic Component (AC) This aspect of the index was developed in an attempt to assess the aesthetic handicap posed by a malocclusion and thus the likely psychosocial impact upon the patient – a di cult task! - Score 1 or 2 — none - Score 5, 6, or 7 — moderate/borderline - Score 3 or 4 — slight - Score 8, 9, or 10 — de nite For treatment in the UK the IOTN score that is needed to be eligible for orthodontic treatment is: - DHC = 5 - DHC = 4 - DHC = 3 AND AC > 6 An acronym that’s used to ease the assessment of the DHC is: MOCDO M - Missing Hypodontia - the developmental absence of one or more teeth excluding the third molars. 4h - Less extensive hypodontia requiring pre-restorative orthodontic space closure to obviate the need for a prosthesis. 5h - Extensive hypodontia with restorative implications (more than one tooth missing in any quadrant) requiring pre- restorative orthodontics. Impaction – A tooth that fails to erupt into the dental arch due to the reasons below. 5i - Impeded eruption of teeth (with the exception of third molars) due to Crowding, Retained deciduous teeth Displacement, Pathological cause. Presence of supernumerary teeth, **Watch out for retained Cs and palpate at 8-10 years 1 of 4 fi fi fl ffi O - Overjet – the horizontal distance between the most prominent upper and lower incisor. 3a - Increased overjet 3.6–6 mm with incompetent lips. 4a - Increased overjet 6.1–9 mm. 5a - Increased overjet > 9 mm. 3b - Reverse overjet 1.1–3.5 mm 4b - Reversed overjet > 3.5 mm with no masticatory or speech di culties 4m - Reverse overjet 1.1–3.5 mm with recorded masticatory and speech di culties 5m - Reverse overjet >3.5 mm with reported masticatory and speech di culties C - Crossbite is a discrepancy in the buccolingual relationship of the upper and lower teeth. 3c - Anterior or posterior crossbites with 1.1–2 mm discrepancy 4c - Anterior or posterior crossbites with greater than 2 mm discrepancy between retruded contact position and intercuspal position 4l - Posterior lingual crossbite with no functional occlusal contact in one or both buccal segments D - Displacement refers to crowding and the distance between the contact points. 3d - Displacement of teeth 2.1–4 mm 4d - Severe displacement of teeth, greater than 4 mm O - Overbite how much the maxillary incisors overlap the mandibular incisors vertically. 3f - Increased and complete overbite without gingival trauma 4f - Increased and complete overbite with gingival or palatal trauma Anterior Open Bite no vertical overlap of the incisors when the buccal segment teeth are in occlusion. 3e - Lateral or anterior open bite 2.1–4 mm 4e - Extreme lateral or anterior open bites, greater than 4 mm Others – IOTN 4 4x - Supplemental teeth 4t - Partially erupted teeth, tipped and impacted against adjacent teeth Others IOTN 5 5p - Defects of cleft lip and palate 5s - Submerged deciduous teeth Aesthetic Component The aesthetic component comprises a set of ten standard photographs, which are also graded from score 1, the most aesthetically pleasing, to score 10, the least aesthetically pleasing. The scores are categorized according to need for treatment as follows: - score 1or 2—none - score 3 or 4 — slight - score 5, 6, or 7— moderate/borderline - score 8, 9, or 10 — de nite Many disadvantages associated with the aesthetic component and is not to be used alone! Only in association with the DHC of the IOTN. 2 of 4 fi ffi ffi ffi 3 of 4 4 of 4