Quality Resource Guide

Managing the Patient with a Worn Dentition 3rd Edition

www.metdental.com

case must first be evaluated using a diagnostic

mounting and initial occlusal stability must be

achieved by removing all interferences in CR.

This can be achieved through equilibration of the

mounted casts; the goal being to develop stable

occlusal stops on the posterior teeth. Any contacts

on sloping surfaces that might force the mandible

anteriorly or laterally during closure should be

eliminated.

Once adjustments are shown to be

appropriate on the casts, they may be duplicated in

the patient’s mouth.

Once equilibrated, CR should coincide with MI.

Figure 23

shows the anterior teeth in maximum

intercuspation. Following equilibration and the

changing of mesial slope contacts to a stable flat

contact (creating a stable posterior occlusion), the

anterior teeth are no longer the stopping force

for the closure of the mandible. Equilibration of a

patient with a significant posterior-anterior shift,

and contact on the functional cusps may not lend

itself to an easy equilibration.

The diagnostic

mounting will aid in the analysis of the ability

to equilibrate and the possible prognosis of the

equilibrated case.

A diagnostic wax-up is completed on the mounting

to reestablish a stable occlusal scheme (

i.e.

guidance and cusp-fossa, or cusp-marginal

ridge, occlusal contacts on the posterior teeth)

(

Figure 24

). This enables the posterior teeth

to bear the forces of mandibular closure and

restores the class III lever advantage to the

anterior teeth. An occlusal scheme separating

the posterior occlusion by 1mm when the cuspids

are in lateral contact is the preferred relationship.

Keeping the incisal guidance shallow for patients

with a bruxism habit will aid in reducing the force

on the anterior teeth during lateral movements of

the mandible.

Duplicating the diagnostic wax-up can assist the

clinician in fabricating provisional restorations.

Placing these provisional restorations allows the

patient and the clinician to assess the proposed

occlusion and view the esthetics prior to the

fabrication of final restorations.

The provisional

restorations should reflect the desired esthetic

result, the change in the occlusal scheme, and

should be individualized to allow normal tissue

contacts allowing normal home care, including

flossing. Care should be taken to ensure that the

mandible is able to move throughout its entire

envelope of function without interferences.

The occlusal vertical dimension, or Vertical

Dimension of Occlusion (VDO), may be opened at

this time, if necessary. A change in the VDO must

be undertaken with care. A change can be tested

with the use of an orthotic appliance (removable

overlay splint) at the new VDO, followed by

building provisional restorations at that position

(

Figures 25 and 26

). This allows the patient to

evaluate the new VDO for function and comfort.

The length of time for the patient to use the orthotic

appliance is a clinical decision by the restoring

dentist. Spear recommends evaluation of the

appliance in 4-8 weeks.

The main criteria is the

comfort of the patient. Some clinicians prefer to

move directly to provisional restorations, and do

not feel there is a need for the orthotic or testing

an increased VDO.

Because the orthotic is a

conservative and reversible procedure, the authors

recommend its use.

If the patient is able to function normally with

the provisional restorations, replacement with

definitive restorations will predictably result in a

favorable outcome. The provisionals will provide

the clinician with information regarding optimal

occlusal contacts. The dentist and the patient

can observe esthetic form for the anterior teeth.

Are they too long? Are they too wide? Is there

a need for diastemas? The disocclusion of the

posterior teeth can be observed and worked out

in the provisional restoration. Once the esthetic

and functional desires of the patient and restoring

dentist are satisfied, restoration can begin.

The clinician may need to consider endodontics

and post/cores in order to have sufficient tooth

substructure to retain an artificial crown. Crown

lengthening may also be an option if there is

sufficient bone to support the teeth after the

procedure is completed. If crown lengthening is

indicated, the authors will normally wait three

months prior to beginning final restorations.

Attempting to complete all final restorations

at the same time can be overwhelming. The

authors feel a reasonable alternative is to divide

the treatment into segments. First, fabricate

permanent restorations for the anterior teeth to

restore anterior guidance. Then complete the

posterior restorations, doing both upper and lower

teeth on one side of the mouth at one time. If

desired, all teeth can be restored at once, but a

clinical remount will be required to insure stable

contacts and excursive movements.

Since the VDO and all excursive movements have

been worked out using provisional restorations,

there is no need to lute the final restorations with

temporary cement. Provisional restorations are

easy to remove with an instrument pressed into

the resin. The provisional restorations flex under

stress, breaking the cement seal and allowing

removal. Well-done final restorations will have

smooth margins making it difficult to use an

instrument to remove them. Final restorations will

not flex, and will resist removal. It has been the

authors’ experience that temporarily cemented

final restorations often cannot be removed.

Since the provisionals have already been tested,

there is no reason to temporally cement the final

restorations.

Despite achieving perfect cuspid guided disclusion

with a full-mouth rehabilitation, parafunctional

behavior will probably persist for the bruxism

patient, making the use of a nighttime protective

appliance mandatory. The continued parafunctional

activity can destroy even the most meticulously

restored dentition.

Knowledge of materials used for the reconstruction

is important. The use of strong materials will aid in

preventing the loss of restorations over time due to