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Awell-finished orthodontic case has the properalignment of crowns and roots and level mar-ginal ridges. With preadjusted brackets

(straight-wire appliances), the position of the bracket onthe crown determines the tooth’s final tip, torque,height, and rotation.1,2 Poorly positioned brackets resultin poorly positioned teeth and necessitate many morearchwire adjustments. This can lead to an increase intreatment time or a final occlusion that is less than ideal.

Poor bracket positioning can render even the mostcustomized prescription ineffective. Consider the end-less number of bracket prescriptions on the market.Most differ by only a few degrees. Now, consider howmuch one can change the prescription by misplacingthe bracket on the tooth.3

Orthodontists go to great lengths to ensure that eachbracket is positioned as ideally as possible. Unfortu-nately, even under the best of circumstances, idealbracket placement during initial bonding is oftenimpossible because of limitations brought on by theexisting malocclusion or operator error.4-6 Initial level-ing often reveals bracket-positioning errors. The ortho-dontist should first recognize and then correct theseerrors early in the treatment process so that wire adjust-ments can be minimized later.

The protocol below describes 5 steps for achievingcrown and root alignment. We recommended thateach step be performed on every patient undergoingfully banded therapy. Once integrated into the treat-

ment protocol, it can decrease treatment time andimprove final results.

STEP 1: INITIAL BRACKET POSITIONING

Ideally positioning brackets during initial bondingis challenging. Journal articles have described manydirect and indirect bonding techniques in an effort toimprove initial placement accuracy.7-14 Most of thesebonding techniques have in common 4 elements thatdemand attention when positioning brackets: (1) baseadaptation, (2) rotational position, (3) vertical position,and (4) slot angulation. Regardless of the bonding tech-nique used, one should strive to optimize each bracketplacement relative to these 4 categories.

First, check to see that the contour of the bracketbase follows the contour of the tooth’s surface. Thebracket base may need to be modified to fit some teetheither by flattening the base or by increasing its con-cavity. An ideal base contour helps to ensure an evenflow of adhesive during bracket seating. However,even when the contour of the bracket base is ideal,incomplete bracket seating can lead to unwanted rota-tions (Fig 1).

Second, evaluate the rotational position of eachbracket from the occlusal (Figs 2-5). Center the bracketmesiodistally for incisors and in line with the labialcusp tips for canines and premolars. Center the bracketin the buccal groove for molars.

Third, determine the vertical position of each bracketby using well-fitted molar bands as benchmarks for thevertical position of the rest of the appliance. Position allthe posterior brackets so the distance from the archwireslot to the marginal ridge is equal for all neighboringteeth (Fig 6). This will result in even marginal ridgeswhen a straight wire is used. The distances from the slotsto the cusp tips may vary. The anterior brackets shouldbe positioned on the basis of the heights of the posterior

aAssistant Professor of Orthodontics, University of the Pacific; and in privatepractice.bAssociate Clinical Professor of Orthodontics, University of California, SanFrancisco; and in private practice.Reprint requests to: Sean K. Carlson, 163 Miller Ave, Mill Valley, CA 94941.Submitted and accepted, March 2000.Copyright © 2001 by the American Association of Orthodontists.0889-5406/2001/$35.00 + 0 8/1/111220doi:10.1067/mod.2001.111220

CLINICIAN’S CORNER

Bracket positioning and resets: Five steps toalign crowns and roots consistently

Sean K. Carlson, DMD, MS,a and Earl Johnson, DDSb

Mill Valley, Calif

Orthodontists strive for accurate bracket positioning because it makes achieving a superior occlusion easier.Whether one uses a direct or an indirect bonding technique, the initial appliance placement typically includessome bracket-positioning errors. The clinician either corrects these errors during treatment or tediouslyrepeats archwire bends to compensate for the misplaced brackets. The clinician should assess bracketpositioning early in treatment by clinical and radiographic evaluations and then correct all positioning errorsduring a single dedicated reset appointment. This article describes a 5-step protocol for assessing andcorrecting bracket-positioning errors. (Am J Orthod Dentofacial Orthop 2001;119:76-80)

American Journal of Orthodontics and Dentofacial Orthopedics Carlson and Johnson 77Volume 119, Number 1

brackets. The canine and adjacent premolar bracketsshould be positioned equidistant from the cusp tip, orwith the canine cusp tip just slightly further from thebracket slot. Upper incisor brackets should be positioned

in such a way that they can establish proper gingival andincisal edge relationships (Fig 7).15 Position the lowerincisor brackets at equal distances from the incisal edgesand slightly more incisally than the neighboring canines(Fig 8). Do not use fractured or worn incisal edges asguides for bracket positioning.

Finally, determine the desired slot angulation ofeach bracket by evaluating the position of the roots.Use periapical radiographs as a guide during initialbracket placement (Fig 9). If the root is well aligned onthe initial radiograph, be sure that the slot angulation isneutral. If the root alignment needs correction, incor-porate the needed adjustment into the slot angulationduring initial bracket placement (Fig 10).

STEP 2: PRIMARY EXPRESSION OF BRACKETPRESCRIPTION AND POSITION

After initial bracket placement, the goal is to com-pletely express the bracket’s prescription and positionthrough complete leveling and aligning. For example,

Fig 1. Excess adhesive under mesial of left bracket willlead to undesired rotation.

Fig 2. Ideal rotational bracket positioning for maxillaryincisors as viewed from the occlusal.

Fig 3. Ideal rotational bracket positioning for mandibularincisors and canines as viewed from the occlusal angle.

Fig 4. Ideal rotational bracket positioning for maxillaryposterior teeth as viewed from the occlusal.

Fig 5. Ideal rotational bracket positioning for mandibularposterior teeth as viewed from the occlusal.

78 Carlson and Johnson American Journal of Orthodontics and Dentofacial OrthopedicsJanuary 2001

only that the orthodontist level the bracket slots, finish-ing with a full-sized wire. The resulting tooth-to-toothrelationships should be ideal without wire adjustments.We do not encounter this situation often, but the lessonit provides is an important one—filling the bracket slotprovides complete expression of bracket prescriptionand position.

If, during the initial alignment stage, you find asevere bracket-positioning error, reset the bracketwhile still in the light initial wire (.014 or .016-innickel-titanium). This reduces the need to drop downin wire size at the reset appointment. Minor bracket-positioning errors, on the other hand, are most effi-ciently corrected at the reset appointment after thereset evaluation.

Completely seat a full-sized wire in each bracketslot before moving on to the reset evaluation. Asmaller wire will only partially express the bracketprescription and position. We recommend a .018 ×.018-in Sentalloy wire (GAC International, Islandia,NY) for a 0.018 slot appliance. Allow sufficient time for

consider a patient who has a set of perfectly positionedbrackets with a bracket prescription that is ideal for theshape of the teeth. In theory, treatment would require

Fig 10. Tip adjustment in bracket positioning for secondpremolar with mesial root inclination.

Fig 7. Ideal vertical positions of maxillary anterior brackets.Note differences in incisal edges and gingival margins.

Fig 8. Ideal vertical positions of mandibular anteriorbrackets. Incisor brackets positioned slightly moreincisally than canines.

Fig 9. Periapical radiograph of maxillary posterior teeth.Note mesial root inclination of second premolar.

Fig 6. Ideal vertical positions of posterior brackets. Mar-ginal ridges equidistant from wire slot.

American Journal of Orthodontics and Dentofacial Orthopedics Carlson and Johnson 79Volume 119, Number 1

this wire to completely express the bracket prescrip-tion and position (4-8 weeks).

STEP 3: RESET EVALUATION

The reset evaluation involves both a clinical exam-ination and a radiographic evaluation. For mostpatients, the reset evaluation can take place within thefirst 6 months of active treatment. Perform the clinicalexamination at the appointment before the resetappointment and prescribe a root-paralleling radio-graphic series (Fig 11).

Examine each tooth individually for bracket-positioning errors, paying close attention to base adap-tation, marginal ridge height discrepancies, crown rota-tions, and nonparallel roots. We note the deficiencies in

each category in a specially designated area on thepatient’s chart (Fig 12).

Use abbreviations to specify the necessary resetinstructions for each bracket. Our recommended abbre-viations are as follows: a check mark indicates pooradaptation of the bracket base to the tooth. This mightbe a bracket that was not fully seated or a band with adistorted margin. An “MO” or “DO” indicates a rota-tional deficiency. An “MO” indicates that the mesial ofthat tooth needs to be rotated out toward the labial, and“DO” indicates that the distal needs to be rotated out.“I” for intrude and “X” for extrude indicate the neces-sary vertical adjustments. Finally, a “D” indicates thatthe root apex needs to be moved distally and an “M”indicates that the apex needs to be moved mesially.

Fig 11. Root-paralleling radiographic series. Note the mesial root inclination of the mandibular leftfirst premolar and maxillary left lateral incisor.

Fig 12. Bracket-positioning errors noted in a designated area of the patient’s chart. Abbreviations foreach tooth specify necessary reset instructions.

80 Carlson and Johnson American Journal of Orthodontics and Dentofacial OrthopedicsJanuary 2001

STEP 4: RESET APPOINTMENT

The information gathered during the reset evalua-tion are the instructions for the reset appointment.Schedule the reset appointment with adequate time fordebonding, debanding, bracket preparation, toothpreparation, rebonding, and rebanding. We recommendat least an hour for this appointment.

It is easier to position brackets at the reset appoint-ment than it is at the initial bonding. By the resetappointment, the tooth-to-tooth relationships havegreatly improved, making it much easier to assess therelative positions of brackets between neighboringteeth. Also, visibility of each tooth’s facial surface isgreatly improved.

Remove the brackets and bands from teeth withpositioning errors. Clean each tooth of excess compos-ite or cement. Remove excess composite or cementfrom the bands and brackets by using a micro-etcher.Refit each band before cementation. Refitting the bandis particularly important for rotational resets becauseinitial band fitting and burnishing creates a “rotationalmemory” in the band’s metal. This memory can beremoved by reshaping the band with bird-beak pliersbefore refitting. Reposition the bands and bracketsaccording to the principles described in step 1. Use theroot-paralleling radiographs at chairside to determinethe amount of tip correction.

After cementation and bonding, fully engage thesame .018 × .018-in Sentalloy wire (GAC Interna-tional) that was used for primary expression of bracketprescription and position. Use a lighter wire if the posi-tional change of 1 or more brackets was severe.

STEP 5: SECONDARY EXPRESSION ANDFINISHING

After the reset appointment, fully express the newbracket positions by applying the same principles used instep 2. Secondary expression is usually complete within 6to 8 weeks. The amount of time depends on the severity ofthe original positioning errors. After secondary expres-sion, an adjustable wire can be inserted for finishing.

At this stage the orthodontist can be confident thatroot alignment has been achieved and no further adjust-ments for root tip will be needed. Treatment can becompleted with your choice of finishing procedures.

SUMMARY

We have presented a protocol that addresses errorsof initial bracket positioning and facilitates consistentcrown and root alignment. By implementing this proto-col, the clinician can expect decreased treatment timesand superior results. We have found that although repo-sitioning does not completely eliminate the need forwire bends during finishing, it does significantly reducetheir number and complexity. This protocol can beadapted to fit numerous treatment philosophies and canbe applied to an appliance of any slot size.

REFERENCES

1. Swain BF. Straight wire design strategies: five-year evaluationof the Roth modification of the Andrews straight wire appliance.In: Orthodontics: state of the art, essence of the science. StLouis: CV Mosby; 1986. p. 279-98.

2. Creekmore TD, Kunik RL. Straight wire: the next generation.Am J Orthod Dentofacial Orthop 1993;104:8-20.

3. Balnut N, Klapper L, Sandrik J, Bowman N. Variations inbracket placement in the preadjusted orthodontics appliance. AmJ Orthod Dentofacial Orthop 1992;102:62-7.

4. Zachrisson BU, Brobakken BO. Clinical comparison of directversus indirect bonding with different bracket types and adhe-sives. Am J Orthod 1978;74:62-78.

5. Aguirre MJ, King JG, Waldron JM. Assessment of bracketplacement and bond strength when comparing direct bonding toindirect bonding techniques. Am J Orthod 1982;82:269-76.

6. Koo BC, Chung C-H, Vanarsdale RL. Comparison of the accuracyof bracket placement between direct and indirect bonding tech-niques. Am J Orthod Dentofacial Orthop 1999;116:346-51.

7. Silverman E, Cohen M, Gianelley AA, Dietz VS. A universaldirect bonding system for both metal and plastic brackets. Am JOrthod 1972;62:236-44.

8. Moin K, Dogon IL. Indirect bonding of orthodontic attachments.Am J Orthod 1977;72:261-75.

9. Hoffman BD. Indirect bonding with a diagnostic setup. J ClinOrthod 1988;22:509-11.

10. Hickham JH. Predictable indirect bonding. J Clin Orthod1993;27:215-17.

11. Moskowitz EM, Knight LD, Sheridan JJ, Esmay T, Tovilo K. Anew look at indirect bonding. J Clin Orthod 1996;30:277-81.

12. Kasrovi PM, Timmins H, Shen A. A new approach to indirectbonding using light-cure composites. Am J Orthod DentofacialOrthop 1997;111:652-6.

13. Simmons M. Improved laboratory procedure for indirect bond-ing of attachments. J Clin Orthod 1978;12:300-2.

14. Thomas R. Indirect bonding: simplicity in action. J Clin Orthod1979;13:93-105.

15. Garber DA, Salama MA. The aesthetic smile: diagnosis andtreatment. Periodontol 2000 1996;11:18-28