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7 Clinical Techniques for Occlusal Adjustments During Implant Restoration Delivery

7 Clinical Techniques for Occlusal Adjustments During Implant Restoration Delivery

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309



15  Implants in the Aesthetic Zone: Occlusal Considerations

Table 15.4  The five-step occlusal check

Step

Name of

check

Jaw

movement



1

MIP



Posterior

contacts



Even, bilateral

posterior

contacts (cusp

tips, marginal

ridges, and

fossae)



Anterior

contacts



Close teeth

together



2

Lateral

excursives

Move jaw left

and right



No contacts on

posterior teeth

unless group

function is

designed to

lessen load on

canine implant

Anterior teeth No contacts in

touch lightly in anterior teeth

MIP



Implant

restoration

contacts



Implant

restorations

only touch

when patient

squeezes teeth

together



Articulating

paper used



8–12 μm

BLUE paper



3

Protrusive



4

Crossover



5

Chew test



Move jaw

forward



Position teeth

edge to edge,

and move

side to side

No contacts

on posterior

teeth



Chew on wax

for 30 s, then

insert paper,

and chew 30 s

No contacts

on posterior

inclines in

group function

design



No contacts

on posterior

teeth



Even bilateral Even,

smooth

anterior

dis-occlusion surfaces, no

catches,

broad

contact areas

Light

No contacts on No contacts

contacts,

anterior implant on anterior

smooth

implant

restorations if

restorations if surfaces, no

possible

catches,

possible

broad

contact areas

8–12 μm RED

8–12 μm

8–12 μm

paper

RED paper

RED paper



No contacts

on anterior

teeth with

200 μm paper

No contacts

on anterior

implant

restorations

with 200 μm

paper

200 μm paper



The Five-Step Occlusion Check: This system has been developed to respect all

aspects of occlusal theory and provides a practical, repeatable, and reliable method

of insuring predictable results with implant-retained restorations. It has been shown

to provide restorations that are comfortable, more durable, and more successful.

During the following steps, the implant restoration is firmly seated and cemented or

screwed into place, and in the case of a screw access, the final composite cover has

been placed (Table 15.4).

1. MIP Check: With the patient seated upright, thin (8 or 12 μm, Arti-Fol (Bausch) or

Troll Foil (Troll Dental)) articulating paper is positioned between the teeth, and the

patient is instructed to close several times, tapping on their posterior teeth. Contacts

are recorded and analyzed, and the only anterior contact should be the distal of the

maxillary canine. The maxillary incisor lingual surfaces should be free of contacts

at this stage. Then, shim stock is placed between the anterior teeth and the patient

instructed to squeeze. With the teeth held together tightly, the shim stock should be

held by the anterior teeth; however, when the patient bites with normal force, the

shim stock releases. Contacts are then analyzed for their size. The paper is reinserted, the teeth squeezed together, and the contacts analyzed. The contact sizes



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R. G. Stevenson III and A. Agnihotry



should be “slenderized” to be approximately 0.5 mm in diameter on all anterior

teeth, both implant crowns or natural teeth (see Fig. 15.2). It is important that the

implant crowns achieve a positive MIP contact at the squeeze step (shim stock

barely holds), as this will prevent the over-eruption of the opposing tooth and the

lack of occlusal stability. Simply taking the implant crowns “out of occlusion” will

destabilize the occlusion. The teeth will eventually erupt into this space, and this

uncontrolled event may result in other interferences developing. A “light contact”

means that the surfaces do in fact contact, but later and with less force than the

adjacent teeth. With anterior teeth, the desired occlusion for natural teeth is lighter

than posterior teeth, and the occlusion for implant restorations should be slightly

lighter than the natural teeth to allow for the compression of the PDL on the natural

teeth, which may be as much as 0.1 mm or more (Figs. 15.3 and 15.4).

2. Lateral Excursive Check: With the patient seated upright, insert thin red articulating paper between the anterior teeth, and instruct the patient to grind in circles,

and slide side to side. It may be helpful to demonstrate the movement that is

desired with your own jaws. Then insert a thin blue articulating paper, and

instruct the patient to tap, and squeeze as in the MIP check step.

(a) For Canine Guidance: Use when the canine is a natural tooth. Leave the red on

the canine; however, adjust the pattern of the mark in a manner which replicates

the steepness desired and the width of the pathway taken, as it will provide the

proper canine guidance required. When the anterior teeth are not critical to the

protection of the implant crown (the canine is a natural tooth), then adjust the

red marks away from all of the natural incisors and restored implant surfaces.

(b) For Anterior Group Function: Use when the canine is an implant, and it is

desirable to have the natural anterior teeth assist with the guidance. Analyze

and adjust the marks as follows: remove all red contacts from the lingual

surface of the canine implant restored tooth, and leave the blue marks. With

the anterior teeth, adjust the pattern of the marks in a manner which replicates the steepness desired and the width of the pathway taken, as it will

provide the proper anterior group function required.



a



b



c



d



e



Blue and Red

8-micron paper



Metallic 12-micron paper



Blue 8-micron paper



Blue 200-micron paper



200-micron paper



Fig. 15.3  Articulating paper: (a) BLUE and RED 8 μm paper (Bausch Arti-Fol, BK23 and BK21).

(b) Metallic 12 μm paper with shim stock on one surface and ink on the other (Bausch Arti-Fol

BK28). (c) BLUE 8 μm paper with built-in plastic holder (TrollDental TrollFoil). (d) BLUE 200

μm paper for the chew test (Bausch BK05). (e) 200 μm paper being used to perform the chew test



15  Implants in the Aesthetic Zone: Occlusal Considerations



a



b



c



d



311



e



Fig. 15.4 (a) Lingual surface of maxillary central incisor tooth. (b) Lingual surface of maxillary

central incisor tooth with typical MIP contacts (this would barely hold shim stock). (c) Lingual

surface of maxillary central incisor tooth with typical MIP contacts after patient clenches (this

would firmly hold shim stock). (d) Lingual surface of maxillary central incisor implant crown in

MIP (note: lack of contact marks). (e) Lingual surface of maxillary central incisor implant crown

in MIP when patient clenches (note: this would barely hold shim stock)



3. Protrusive Check: With the patient seated upright, insert thin red articulating

paper between the anterior teeth and instruct the patient to slide forward and

back. It may be helpful to demonstrate the movement that is desired with your

own jaws. Then use blue thin articulating paper, and instruct the patient to tap

and then squeeze as in the MIP check step. Analyze and adjust the marks as

follows: remove all RED contacts from the lingual surfaces of the anterior

implant restored teeth, and leave the BLUE marks. Reshape the RED marks on

the natural anterior teeth to the pattern which replicates the steepness desired

and the width of the pathway taken, as it will provide the proper anterior protrusive guidance required. Do not allow implant anterior teeth to perform protrusive guidance, when natural teeth are available to carry the load. When

nothing but implant restorations are present in the anterior segment, distribute

the forces as evenly as possible among all of the surfaces involved in the

guidance.

4. Crossover Check: With the patient sitting upright, insert the thin red paper,

and instruct the patient to move into edge-to-edge position, and move their

teeth edges against the opposing anterior teeth—side to side and from a protrusive (underbite) position backward. Look to see that the incisal edges are

broad and allowing for smooth movements, without catching the corners of

the incisal edges. The adjustments may likely require the adjustment of the

incisal edges of natural mandibular teeth. This step is best completed in the

prototypes, before final impressions are made to avoid the unpleasant situation of explaining the need to fit “their teeth” to “your restorations.” This step

rarely requires much more than a ceramic polishing abrasive with slow rpm—

in lieu of a high-speed carbide or diamond, which may mitigate patient concerns. With anterior aesthetic restorations, this step is necessary on most

patients during the prototype phase and met with little resistance from the

patient. When it is a preplanned step and is described before treatment is



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R. G. Stevenson III and A. Agnihotry



initiated, it is readily accepted by patients. The crossover check is an extremely

important step to prevent chipping of incisal edges of final restorations and,

when performed routinely, will measurably enhance patient comfort and restoration longevity.

5. Chew Test: With the patient sitting upright, instruct them to chew naturally on a

thimble-sized piece of tray periphery wax, while inserting a piece of thick red

200  μm (Bausch BK05) between the anterior teeth. It is helpful to have the

patient chew on this piece of “sterile” wax without the clinician watching,

which seems to allow the patient to chew more naturally. After 10 s, turn toward

them, and instruct them to continue chewing, and insert the paper when access

is available, and have them continue chewing, again with your back turned.

After another 10 s or so, remove the paper, and then use a blue thin articulating

paper, and instruct the patient to tap and then squeeze as in the MIP check step

to analyze the marks on the lingual surfaces of the anterior teeth. Remove all red

marks on the anterior teeth, as these are the functional pathway interferences

which may lead to untoward forces on the teeth and implant restorations. It is

best to remove all red marks during this exercise, whether they exist on teeth or

implant restorations. Repeat the test until no red marks can be made on the lingual surfaces of the anterior teeth while chewing. The 200 μm paper is thick

enough to allow for an adequate space for non-frictional dynamic occlusal functionality (Fig. 15.5).



15.8 Polishing After Adjustments

It is incumbent on the clinician to research the best available polishing systems for

achieving a highly polished and comfortable surface after making occlusal adjustments. For all currently available ceramic systems (i.e., zirconia, lithium disilicate,

leucite, feldspathic), the correct bur for adjustments is a 30  μm diamond [40].

Carbides are contraindicated on ceramics as they have been shown to cause microcracks. The surface left by the fine diamond must be polished to a high luster to

mitigate future crack propagation [40]. Numerous systems exist which provide

varying level of smoothness; however, they must be used after the occlusion has

been adjusted with the fine diamond bur (Table 15.5).



15.9 Engineering Checks at Follow-Up Appointments

After the final delivery of the aesthetic zone implant restoration, these five checks

should be employed at re-care appointments to mitigate forces and fine-tune the

occlusion over time, as natural wear and tooth movement occurs over time. True

occlusal stability is a dynamic event and hence a moving target that requires our

most conscientious attention to detail.



15  Implants in the Aesthetic Zone: Occlusal Considerations



a



b



c



d



313



e



Fig. 15.5 (a) Occlusal view of maxillary premolars and anterior teeth. (b) Occlusal view of maxillary premolars and anterior teeth with implant restored crowns at the maxillary right central incisor and maxillary left canine positions prior to occlusal analysis with articulating paper. (c)

Optimal occlusal marking with thin articulating paper of b in MIP. (d) Optimal occlusal marking

with thin articulating paper of b in MIP with the patient clenching (note: the lighter occlusion on

the implant crowns, which would barely hold shim stock). (e) Optimal occlusal marking with thin

articulating paper of b in eccentric movements with red paper showing canine guidance on the

right and optimal protrusive markings (note: no marks exist on the implant crowns in any movement, and group function is established on the left, decreasing the load on the canine)



15.10 Occlusal-Related Failures

When a patient complains that an implant crown “is loose,” or “something moved,”

or “something chipped,” it is natural for any conscientious clinician to experience

significant concern. Even with best efforts, this is a dynamic situation on a human

being and not a static machine. Humans do things with their teeth that cannot be

predicted, and their dentistry, however well planned, engineered, integrated, and

adjusted into the body, is prone to failure over time. Reentering a fractured screw-­

retained restoration is relatively simple, but “repairs” nearly always require a



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