Treatment of malposed anterior teeth in adults

Treatment Ira Franklin

Milburn,

of malposed

anterior

teeth

in adults

Ross, D.D.S.

N. J.

M

alposed anterior teeth may produce many undesirable effects in adults. They may give rise to destructive occlusal forces that will cause trauma from occlusion; they may fail to deflect food adequately, causing irritation of the gingiva; they may not allow sufficient space for an adequate amount of interproximal gingiva; they may predispose to fenestration or dehiscence of the labial cortical bone; and/or they may be unesthetic. Malposition has been treated by many techniques, some simple and some quite complex. Some of the significant criteria for selecting a specific technique are that it ( 1) eliminate or markedly reduce the original problems, (2) produce minimal discomfort and pain, (3) have a minimal number of unfavorable sequelae, (4) require an amount of skill commensurate with the ability of the therapist, and (5) be completed in a reasonable period of time. Coronal reshaping, a technique for reshaping the teeth by grinding, fulfills these objectives for many people. Coronal reshaping refers to reshaping all surfaces of the teeth that are involved in both masticatory and nonmasticatory function? When indicated, coronal reshaping should be done on all teeth, both anterior and posterior. Reshaping only one tooth or one group of teeth by “spot grinding” may reduce occlusal pressures in one area but may increase them in another, thus creating new problems as \ve attempt to eliminate old ones. Because space is limited, this discussion will deal with only the anterior teeth. However, it should be understood that the posterior teeth should also be reshaped. Coronal reshaping is almost never done alone. It is usually done in conjunction with other types of therapy. INDICATIONS

FOR CORONAL

RESHAPING

Coronal reshaping should be done only when destructive occlusal forces have injured the periodontium to a significant degree. It should not be done as a prophylactic measure when there is not significant evidence of trauma from occlusion. Significant evidence of injury (trauma from occlusion) includes such changes as increased tooth mobility, migration of teeth, loss of alveolar bone, pain during chewing (not caused by pulpal pathosis), temporomandibular joint dysfunction associated

43

44

Ross

Fig. 1. Teeth of a 62-year-old woman. The space between the maxillary central incisors closed after coronal reshaping and treatment of the soft tissues. There is also improvement in the incisal edge level and labial curvature of the maxillary and mandibular incisors. Tht, II~O\I’. mcnt occurred without the use of an appliance of any type. (A) Thr teeth in the ilitcI,(li\li;i; position and (B) in the open position before treatment. The teeth in the intprcuspal po\iric:!: (C) and in the open position (D) after treatment. with

occlusal forces, and v.ertical food impaction caused by occlusal factors. When one or more of the above changes are present, the specific indications for coronal reshaping of the anterior teeth arc as follows: an uneven incisal level, an irregular labiolingual curve because of overlappin, cr and/or rotation, supraocclusion of the mandibular anterior teeth, and minimal horizontal overlap of the maxillar! over the mandibular anterior teeth. In addition. coronal reshaping has been used successfully on anterior teeth to correct spacing (Fig. I ) ~ cross-bite (Fig. 2 : ~ and pseudo-mesioocclusionz, 3 OTHER

TECHNIQUES

FOR TREATING

MALPOSlTlON

Malposition may also be treated by stripping, orthodontic therapy, rcstorativc. care, extraction, or a combination of two or more of these techniques. I’he technique selected will depend upon se\-era1 factors. Some of the more significant are: 1. What type of malposition is present? How extensive is it? 2. Is periodontal disease present? If so, what type? How extensive is it.’ 3. How old is the patient? 4. What is his general health? 5. What result does the patient want ? How much therapy is he prepared to accept?

Volume Number

Treatment

30 1

of malposed

teeth in adults

45

Fig. 2. The teeth of a woman, age 52, have a cross-bite between the maxillary and mandibular cuspids. Note the improvement in the position of the maxillary cuspid after coronal reshaping: A, the intercuspal position; and B, the open position before treatment. The teeth in the intercuspal position (C) and in the open position (D) after treatment.

6. What teeth?

is the training

By lvhat

of the therapist ? Is he motivated

toward

retaining

the

methods?

Stripping is contraindicated in most dentitions. The favorable contact areas between teeth are destroyed when tooth structure is removed from their proximal surfaces. Stripping usually produces straight-line contact areas. This frequently leads to inflammation of the interproximal gingiva, because this part of the gingiva is inadequately protected. Orthodontic care may be helpful but only if the malposition is extreme. Restorative care is indicated primarily to replace missing teeth. Usually, it should not be used

to stabilize

is helpful

mobile

in a few

teeth

patients

if the arch when

is intact.

the space

Extraction

in the arch

of one or more

is too small

teeth

for the number

of teeth present. TECHNIQUE

OF

Mandibular

anterior

CORONAL

RESHAPING

teeth

Treatment is begun on the mandibular anterior teeth by correcting the incisal level and the labiolingual curve. The incisal level may be regular or irregular. In addition, the teeth may be in supraocclusion, at an acceptable level, or in infraocclusion. We can determine whether when

they the

are in supraocclusion

mandibular

teeth

close

by seeing

how

in the intercuspal

the maxillary position

anterior (centric

teeth occlusion).

react If

46

Ross

Fig. 3. Correction of the incisal edges and labial curvature of the maxillary and mandibular teeth of a man, aged 49, by coronal reshaping: A, before treatment; B, after treatment. the maxillary teeth move or if they exhibit tremor during closure in intercuspal position, the mandibular teeth are in supraocclusion. This condition is the result of cithel excessive eruption of the anterior teeth or diminished posterior tooth support. Diminished posterior tooth support may be the result of occlusal wear, loss of one or more posterior teeth with shifting of the adjacent or opposing teeth, or bizarre chewing patterns. Grinding is helpful when there is supraeruption of the anterior teeth. If there is diminished posterior support, restorative care is usually needed to re-establish an acceptable occlusal level. In these situations, grinding may be needed for the anterior teeth. The labiolingual curvature may be regular. or it may be irregular, because oi overlapping of teeth. The curvature may be round: ovoid, square, or tapered. The objective in treating an irregular labiolingual curvature is to rolmd the protruding incisal edges and surfaces of teeth, so that these teeth will blend with the adjacent teeth (Fig. 3). This \\-ill increase the periodontal support of both the maxillary and mandibular anterior teeth by improving the contacts between the opposino teeth. It will also improve the health of the interproximal gingiva by reducing food impaction, assisting in deflecting food, and providing better access for brushing. It is not our objective to convert one type of labiolingual curvature (round. ovoid. or square) to another but rather to make the labiolingual curvature of the patient’s teeth as regular as possible. This will reduce the destructive effects of the irregularity. During the reshaping of the anterior teeth, the position of malposed teeth can also be improved. This is true, frequently, when spacing has developed between a few teeth, lvhen a cross-bite is present betlveen two or three teeth, or if there is ‘1 pseudo-mesioocclusion. The improvement will depend upon the amount of malposition as well as several other factors1 (Fig. 4). Maxillary

anterior

teeth

Protrusive position and excursion. The incisal teeth is corrected by grinding the incisal edges to the incisal edges of the opposing mandibular teeth in Optimum contact in protrusive position implies mandibular anterior teeth contact their maxillary undesirable changes. In many mouths, the maxillary

level of the maxillary anterior produce optimum contact with protrusive position. that the maximum number of opponents without producing central incisors are much longer

Volume Number

30 1

Fig. 4. The teeth of a labial curvature of the the mandibular teeth. open position (A) and incisal edges (D)

Treatment

of malposed

teeth in adults

47

woman, age 51. Note the marked irregularity of the incisal edges and maxillary and mandibular teeth and the crowding and malposition of Note improvement after coronal reshaping: before treatment in the in a labiolingual view (B) ; the open position (C) and as seen from the

than the maxillary lateral incisors. In these situations, it is unwise to make the central and lateral incisors of equal length in an effort to produce contact on all of the maxillary incisors (Fig. 5). In some individuals, optimum contact occurs when only one maxillary incisor is in contact with the mandibular teeth; in others, two or three or more maxillary teeth are in contact. Do not overgrind the teeth! Excessive grinding in any part of the dentition may produce undesirable changes, such as pulp exposure, hypersensitivity, an unesthetic appearance, or temporomandibular joint problems. These side effects are uncommon, but they should be kept in mind during treatment. After obtaining optimum contact in the protrusive position, correct the labial curvature of the maxillary incisors and cuspids, if necessary. If teeth overlap or are rotated, the protruding portion of the labial surface may require reshaping. During this phase of grinding, several potential problems should be anticipated, and steps should be taken to avoid them. Visualize the ultimate shape of the crown before starting, and plan the grinding carefully. Incorrect or excessive grinding may produce an unesthetic result. After correcting the incisal edges, slightly round the incisoproximal corners of the incisors to improve the appearance. Other complications that may arise after the labial curvature is ground are hypersensitivity and exposure of dentin on the labial surface and incisal edge. Note whether the mandible deviates to either the left or the right during pro-

48

Ross

Fig. 5. Optimum contact of teeth is developed in the protrusive position for a woman, Note that the maxillary lateral incisors are not in contact with the opposing teeth.

age 4.:.

excursion. If the mandible deviates. it is usually because of interferenct. from a tooth--this is usually an anterior tooth, but it may be a posterior tooth Eliminate the interference, and check the movement a second time. If necessary! do Repeat this procedure until the additional grinding, and recheck the movement. deviaiton has been eliminated. After correcting the deviation, check for other aspects, and correct them if the) are present. First, determine whether any of the maxillary anterior teeth moltduring protrusive excursion. If so, grind the lingual surface of the tooth that 1’ moving until the mobility is reduced sufficiently. On the tooth to be corrected. grind from (but not including) the point of contact in intercuspal position jcentllr occlusion) to the incisal edge. If it is not possible to eliminate mobility. rcducc~ I: as much as possible. Next check to see whether contact is distributed as evenly as possible on thfi lingual surfaces of both maxillary central incisors. There should be little or no toritact on the lingual surfaces of the lateral incisors. Contact may or may not be present on the cuspids. Usually, contact on the cuspids is necessary during protrusive* excursion only if the central incisors are mobile and/or have considerable loss of alveolar support, Lateral protrusizle positiom and excu7sion.s. Check the lateral protrusive positiol! by having the patient tap his mandibular lateral incisor against the opposing ~naxillary lateral incisor. If there is contact between these two teeth, eliminate the contact by grinding until there is also contact on the adjacent cuspid or crntral incisor or on all three teeth. Repeat this procedure on the maxillary lateral incisor of thr opposite side. Next have the patient tap his mandibular cuspid against the opposing maxiliar) lateral incisor. If there is contact, repeat the procedure described abolc to climinatc or reduce the contact. On the opposite side of the mouth, check the rnandibular cuspid and maxillary lateral incisor in lateral protrusion, and cor‘rcct thr contact. if necessary. slide from tht After correcting the lateral protrusive position, have the patient intercuspal position to the various lateral protrusive positions described previously. trusive

Treatment

of malposed

teeth in adults

49

These sliding movements are lateral protrusive excursions. Check for contact on the lingual surface of the maxillary lateral incisors. If contact is present, grind the lingual surface of the maxillary lateral incisor from (but not including) the intercuspal position to the incisal edge. There should be as little contact on the lateral incisor as possible. The optimum is to have no contact on the lateral incisor in the lateral protrusive positions and during the lateral protrusive excursions. Lateral position and excursion.. The final aspects to be checked are lateral position and excursion. Eliminate all contact on the maxillary anterior teeth in lateral mandibular positions and during lateral excursions. \Yhen this contact occurs, it is usually destructive. SUMMARY

Malposed anterior teeth frequently cause difficulty in adult patients. In many in conjunction with other therapy is effective in dentitions, coronal reshaping eliminating or reducing these problems. Indications for and the technique of coronal reshaping are discussed in this article. References 1. Ross, I. F.: Occlusion. A Concept for the Clinician, St. Louis, 1970, The C. V. Mosby Company. 2. Ross, I. F.: Acquired M&o-Occlusion in the Adult; Diagnosis and Treatment, J. Periodontal. 34: 246-253, 1963. 3. Ross, I. F.: Acquired Mesio-Occlusion in the Adult, J. N. J. State Dent. Sot. 36: 298-305, 1965. MEDICAL ARTS BLDG. 116 MILLBURN AVE. MILLBURN, N. J. 07041