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5 Clinical Recommendations and Case Scenarios

5 Clinical Recommendations and Case Scenarios

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226



P. Papaspyridakos and T. R. Schoenbaum



1 . Single implant in the aesthetic zone

2. Two adjacent implants in the aesthetic zone

3. Multiple implants in the aesthetic zone



10.5.1 Single Implant in the Aesthetic Zone

For single implant impression in the aesthetic zone, the customized impression coping technique is recommended, with either a closed-tray or an open-tray approach.

The reason is that the shape of the teeth in the CEJ level is triangular and wider

compared to the circular impression coping. Capturing the transmucosal part of the

provisional implant crown is a crucial step prior to the implant impression and can

be done either with a pickup of the provisional or with customized impression copings [65, 66]. In regard to the provisional crown, it has to be highlighted that even

though the retention type can be either screw or cement and both yields similar

survival rates, screw retention is preferred for the provisionalization phase of the

implant treatment in the aesthetic zone [67].

The implant impression after customizing the impression coping is poured either

with only in stone without any soft tissue moulage when bone-level type implants

have been placed or with stone and soft tissue moulage when bone-level or tissue

level implants have been placed. The stone cast without the soft tissue moulage

features the customized transmucosal design captured with the customized impression technique and will force the laboratory technician to duplicate this transmucosal part in the final prosthesis without room for error. When the soft tissue moulage

technique is used, which is a commonly used technique, attention must be given, so

that the laboratory technician will not alter the customized transmucosal part due to

the resiliency of the soft tissue moulage. A case is illustrated (Fig. 10.1a–h).



10.5.2 Two Adjacent Implants in the Aesthetic Zone

For impression of two adjacent implants in the aesthetic zone, only the customized

impression coping technique is recommended [51, 52, 65]. Pickup impression of the

two-unit screw-retained provisional prosthesis may not be possible due to the nonengaging components. If a pickup of the screw-retained prosthesis is done, then the

rotation (timing) of the engaging part of the implants will not be captured, rendering the

impression erroneous if a cement retained prosthesis or individual units are envisioned.

The aforementioned procedures are used again to fabricate the customized

impression copings. Prior to the open-tray impression, the customized impression

copings are connected to the implant platforms, and seating is confirmed radiographically. Prefabricated resin bars can be fabricated prior to the impression taking with a previously described technique. Drinking straws are filled with visible

light-­cured resin (Triad gel) and then light cured, thus creating resin bars of standardized thickness and shape. The resin bars are subsequently removed from the

straws and recured. The resin bars are stored for 24  h prior to being used. The

prefabricated resin bars are used to splint the impression copings together with the

aid of additional light-cured resin (Triad gel). If prefabricated bars are not



10  Enhanced Implant Impression Techniques to Maximize Accuracy



a



227



b



c

d



e

f



g

h



Fig. 10.1 (a) Missing maxillary left lateral incisor (#10) was replaced with a dental implant. Peri-­implant

soft tissue conditioning was done for a period of 3 months with a provisional screw-­retained implant

single crown, after successful osseointegration. The natural lateral incisor crown is triangular at the CEJ

cross section, while the dental implant prosthetic neck is circular. The provisional implant single crown

was used to condition the peri-implant soft tissue into the desired shape and emergence profile. (b)

Customized impression coping duplicating the transmucosal part of the provisional implant single

crown. The transmucosal part of the impression coping is fabricated with autopolymerizing acrylic resin

with the indirect technique. Note that the buccal aspect is highlighted with black tip pen. Alternatively,

the customized impression coping can be fabricated intraorally with light polymerizing resin with the

direct technique. (c) Customized impression coping duplicating the transmucosal part of the provisional

implant single crown. (d) Customized impression coping placed intraorally, after removal of the provisional implant single crown. (e) Definitive open-tray implant impression with customized impression

coping. The implant analog will be screwed into the coping prior to pouring of the impression. (f)

Working cast poured in low expansion stone without soft tissue moulage. The customized impression

coping has captured the transmucosal part of the provisional implant single crown, guiding the laboratory

technician to precisely duplicate the transmucosal part into the emergence profile of the final implant

single crown. (g) Occlusal view of definitive screw-retained implant single crown prior to final insertion.

(h) Frontal view of definitive screw-retained implant single crown after final insertion



228



a



P. Papaspyridakos and T. R. Schoenbaum



b



Fig. 10.2 (a) Missing right and left central incisors (#8 and 9) were replaced with two dental

implants. After successful osseointegration and fixed provisionalization for a 3-month soft tissue

conditioning period, the definitive implant impression was taken. Customized impression copings

duplicating the transmucosal part of the provisional implant single crowns were used for the definitive implant impression. The customization was done with the indirect technique. (b) Working cast

poured in stone with soft tissue moulage. The customized impression copings have captured the

transmucosal part of the provisional implant single crowns, guiding the laboratory technician to

precisely duplicate the transmucosal part into the emergence profile of the final crowns



available and the splinting is done directly intraorally, then the splinting is sectioned with a disk bur to compensate for polymerization thickness and reconnected with minimal amount of light-cured resin (Triad gel). The splint is left

untouched for 5 min.

The impression material (polyether or addition PVS) is loaded on the custom

tray and is also syringed around the impression copings, followed by placement of

the loaded tray on the master cast and appropriate positioning intraorally. After

material polymerization, the impression copings are unscrewed, and the impression is removed from the mouth. After connection of the implant analogs to the

impression copings and application of soft tissue moulage, low expansion (0.09%)

type IV die stone is mixed prior to pouring the impression with stone. All of the

stone mixes were vibrated before and during the pouring. The stone casts are

allowed to set for 1 h, as per manufacturer’s recommendation, before separation

from the impressions. Subsequently they are trimmed and finished. A case is illustrated (Fig. 10.2a, b).



10.5.3 Multiple Implants in the Aesthetic Zone

For impression of multiple implants in the aesthetic zone, the customized coping

technique is recommended for definitive implant impressions [51, 52, 65]. The

aforementioned procedures are used again to fabricate the customized impression

copings. Prior to the open-tray impression, the customized impression copings are

connected to the implant platforms, and seating is confirmed radiographically.

Prefabricated resin bars can be fabricated prior to the impression taking with a



10  Enhanced Implant Impression Techniques to Maximize Accuracy



229



previously described technique. Drinking straws are filled with visible light-cured

resin (Triad gel) and then light cured, thus creating resin bars of standardized thickness and shape. The resin bars are subsequently removed from the straws and

recured. The resin bars are stored for 24 h prior to being used. The prefabricated

resin bars are used to splint the impression copings together with the aid of additional light-­cured resin (Triad gel). The splint is left untouched for 5  min. The

impression material (polyether or addition PVS) is loaded on the custom tray and is

also syringed around the impression copings, followed by placement of the loaded

tray on the master cast and appropriate positioning intraorally. After material polymerization, the impression copings are unscrewed, and the impression is removed

from the mouth. After connection of the implant analogs to the impression copings

and application of soft tissue moulage, low expansion (0.09%) type IV die stone is

mixed prior to pouring the impression with stone. The use of stone without soft tissue moulage can also be done alternatively, only if bone-level type implants have

been placed and small amount of wax is added on the impression coping-analog

interface.

First, the stone is mixed manually with distilled water for 15 s to aid the incorporation of the water and then under vacuum, and an initial pour of stone up to the

middle of the analogs is carried out. All of the stone mixes are vibrated before and

during the pouring. After 30 min, the second pour of vacuum-mixed die stone is

done. This double pouring technique minimizes the volumetric expansion of the

stone and has been shown to lead in more accurate working casts. A case is illustrated (Fig. 10.3a–f).



10.6 C

 hecklist and Step-by-Step Protocol to Maximize

Impression Accuracy

For implant impressions in the aesthetic zone, the customized impression coping

technique is recommended. Regarding implant impressions in the anterior aesthetic

zone, there are various scenarios.

Clinical

scenario

Single implant

in the aesthetic

zone

Two adjacent

single implants

in the aesthetic

zone



Impression

technique

Either open

or closed

tray

Either open

or closed

tray



Open tray

Multiple

implants in the

aesthetic zone



Customized

impression

coping

Yes

Yes



Yes



Cast

verification

No



Pouring

technique

Stone, with or

without soft

tissue moulage

Yes if splinted Yes if splinted Stone, with or

without soft

restorations

restorations

tissue moulage

No if

No if

individual

individual

restorations

restorations

Yes

Yes

Stone, with or

without soft

tissue moulage



Splint or not

No



230



a



P. Papaspyridakos and T. R. Schoenbaum



b



c

d



e

f



Fig. 10.3 (a) Missing right lateral and central incisors and left central incisor (#7, 8, and 9) were

replaced with two dental implants for a three-unit implant-supported fixed dental prosthesis (FDP).

After successful osseointegration, peri-implant soft tissue conditioning was done for a period of

3 months with a provisional screw-retained FDP. (b) Partially edentulous area after peri-implant

soft tissue conditioning. (c) Customized impression copings duplicating the transmucosal part of

the provisional implant FDP. The indirect technique was used for fabrication of the customized

copings. (d) Customized impression copings placed intraorally, after removal of the provisional

implant FDP. Copings are splinted together with prefabricated light polymerized resin bar, in order

to enhance the accuracy of the implant impression. Minimal amount of light polymerizing resin

was used to lute the prefabricated resin bars to the copings. (e) Working cast poured only in stone

without soft tissue moulage. The customized impression copings have captured the transmucosal

part of the provisional implant FDP, guiding the laboratory technician to precisely duplicate the

transmucosal part into the emergence profile of the final FDP. (f) Screw-retained final FDP seated

on the working cast. The emergence profile and transmucosal contours of the final FDP are a duplicate of the provisional FDP, captured with the customized implant impression. Note the palatal

windows to confirm accurate seating of the FDP to the implant prosthetic platforms



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