Bonding for an exquisite Finish/ Part I: Concepts of Bracket Bonding Dalia El-Bokle

orthodontics In summary

Join me for a summary of Dalia El Bokle’s lecture exploring finishing in orthodontics. Part 1 focuses on bracket positioning concepts and Dalia’s own take to achieve more predictable ideal outcomes

Current bracket positioning technique

1. Middle middle – middle vertically and horizontally (FA point)

o Challenges

§ Accuracy = measure each tooth

§ If gingival swelling / not fully erupted = inaccuracy

2. Bracket charts – use of bracket gauges

o Accurate and reproducible, introduced in 1994

§ Typical chart

· Upper incisor 4-4.5mm from invasive edge

· Lateral 0.5mm incisal than lateral

· Canine 1mm more gingival than central

o Challenges

§ Appropriate for ideal tooth sizes only, can result in uneven marginal ridge heights if tooth size discrepancy present = bone loss, food impaction, premature contact and relapse

§ Can flatten smiles

3. Smile arch protection (SAC) Tom Pitts

o Bonding for consonant arch

o Method

§ Canine gingival to the contact point

§ Lateral 0.75-1mm cervical to the canine

§ Central 1.5mm more cervical to the canine

· Side effects – oral hygiene and deep bite

Solution by Dalia

Customised approach

· Factors

§ Marginal ridge heights, Upper incisor show, tooth size and shape, Incisor inclination, Overbite

· Method of positioning

1. Mesiodistal

§ All teeth bond in centre of the teeth

§ Molars – if extra cusp = tube design = mesial position and distal in rotation

· Solution = bond centre of the tooth, even if not in Mesiobuccal grove = extra composite used or modify bracket

§ Canine = EXCEPTIONS

· Place bracket mesial to long axis

· Mesial in rotation if placed in the centre

o Requires mesial out rotation to align with the lateral incisor

o Solution

§ Place upper and lower canines mesially

2. Axial (tip)

§ Draw long axis on the model

§ Use of OPG / CBCT to draw long axis

§ Modifications

· Overcorrect 5 degrees adjacent to extractions = prevent dumping in

· Overcorrect severely tipped teeth (usually in case of early loss of 1st molar)

3. Vertical

§ Posterior bond first 7-3

· Bond relative to marginal ridges – not incisal edges Kelange technique 2007

· Draw marginal ridge height line, then slot line

· Canine same level as premolars for marginal height

§ Anterior positioning

· Lateral = bracket gauge of the canine to tooth tip, add 0.25mm (more cervical)

· Central – add 0.25-0.5mm than canine

o = subtle smile arc protection

o Subtle smile arc – less steep difference in connectors when compared to SAP by Tom Pitts

§ Modifications

· 3-3 bonded 1mm more gingival = AOB / reduced incisal show, or 1mm more incisal for deepbite / gummy smile

§ Lower arch

· Canines are bonded 0.5mm more cervical for canine guidance

· Deep bite = 1mm more incisal

Incisal recontouring

· At the beginning of treatment = visually aid final position and improve aesthetics for patient