Anterior Tooth Replacement for a Periodontally Compromised Patient

There are multiple, well-established options for the replacement of a single missing anterior tooth in a patient with a healthy dentition, including delivery of a removable partial denture, a fixed partial denture, a resin-bonded fixed partial denture (ie, Maryland bridge), or an implant-supported restoration-all of which all have advantages and disadvantages to their use. However, when the proposed abutment teeth have periodontal disease, as well as demonstrate excessive bone loss and mobility, options for replacement become more limited. Additional challenges present themselves when there is severe crowding and an immediate replacement option is desired.

This case report reviews the use of a CAD/CAM-fabricated single-wing composite bridge with a fiber reinforcement ribbon splint for the immediate replacement of a mandibular anterior tooth in a periodontally compromised patient. An immediate esthetic result was achieved that also aided in the stabilization of the remaining anterior teeth. This solution addressed several of the challenges presented by the case, including the need to immediately replace a single tooth in a patient with periodontal disease, to splint teeth with mobility due to clinical attachment loss, and to work with limited restorative space. Moreover, there was also the challenge of a time constraint because that was a chief concern for the patient. Treatment options for the replacement of a missing anterior tooth should include immediate replacement that fulfills the cosmetic and functional needs of the patient.¹

Replacement With Stabilization

When mandibular anterior teeth present with mobility due to attachment loss, splinting has been shown to be an effective means of stabilizing them and prolonging their survivability without increasing the risk of tooth loss.² Periodontal splinting is a technique that joins mobile teeth to neighboring stable teeth in order to reduce their mobility and risk of secondary occlusal trauma.³ Because the patient in this case was not a good candidate for other replacement options, replacing the missing anterior tooth with a CAD/CAM-fabricated single-wing composite bridge in combination with a fiber-reinforced composite splint material provided an excellent alternative.⁴ In addition to addressing the chief complaint of replacing the missing anterior tooth, it also served to stabilize the remaining mandibular anterior teeth.

The use of fiber reinforcement ribbon to create a bridge with a natural tooth as a pontic following extraction has been described in the past with clinical success.⁵ Using the natural tooth as the pontic offers the benefit of preserving the original contours, size, and color of the tooth, which can be challenging to duplicate.⁶ However, if the tooth was previously extracted and is no longer available, the traditional options are to do a diagnostic wax-up of the tooth, create a clear matrix, and fabricate the pontic with composite resin or to use a prefabricated denture tooth, which can require extensive reshaping. With the use of CAD/CAM technology, this can be accomplished digitally and without all of the time and materials required by the traditional methods. For this case, an accurate recreation of the patient's original esthetic presentation was able to be achieved through digital design.

Case Report

A 64-year-old male patient presented to the University of Maryland School of Dentistry clinic seeking comprehensive care. Upon initial presentation, the clinical and radiographic findings indicated generalized horizontal bone loss with a vertical bone defect at the mesial aspect of tooth No. 25 and class II mobility, resulting in a periodontal diagnosis of Stage III Grade C periodontitis. The patient underwent scaling and root planing; however, approximately 1 year after its completion, the prognosis of tooth No. 25 was determined to be periodontally hopeless due to the severity of the vertical bony defect, probing depths of 10 mm or more, and ongoing class II mobility (Figure 1 through Figure 3).

The decision was made to extract tooth No. 25, and all clinical options for restoration were discussed with the patient. The patient indicated that he wanted a fixed restoration to replace the edentulous space. In addition, he wanted the restoration to be completed prior to a planned vacation to Brazil that he was leaving for approximately 1 month later. Given the patient's periodontal status and time restrictions, it was decided that the best option to restore the space would be with a single-wing bridge fabricated from a composite CAD/CAM block accompanied by a fiber-composite splint.

Pontic Design and Fabrication

Following the extraction of tooth No. 25 (Figure 4 through Figure 6), an intraoral scanner was not initially available when the patient presented for records; therefore, stone models were made. To reduce chair time, prior to the patient's appointment to restore the tooth No. 25 space, the models were scanned (Omnicam, Dentsply Sirona) (Figure 7) to facilitate the design of a pontic with one facial wing on the distal aspect (Figure 8 through Figure 10). The pontic was subsequently milled (CEREC^® MC XL mill, Dentsply Sirona) from a composite block (Tetric^® CAD, Ivoclar Vivadent). This material was selected for the case for several reasons. Composed of cross-linked dimethacrylate with inorganic fillers, this composite block is available in multiple shades and translucencies to achieve favorable esthetics, and when compared with direct composite materials, it exhibits superior strength.⁷ Furthermore, the milling times are much shorter than those of ceramic block alternatives, and composite blocks do not require crystallization through a firing procedure like ceramics do.

Delivery of the Single-Wing Bridge and Splint

At the restorative appointment, a lip and cheek retractor (OptraGate^®, Ivoclar Vivadent) was placed to achieve proper retraction and isolation during the procedure. The milled pontic was then tried in intraorally to ensure a reliable fit and to confirm that the esthetics met the patient's expectations. In order to create ideal seating of the restoration, modifications were made to the pontic.

Once the modifications were completed, the facial surface of tooth No. 26 was etched with phosphoric acid for 15 seconds, rinsed thoroughly, and air-dried. An adhesive (Adhese^® Universal, Ivoclar Vivadent) was then scrubbed onto the surface for 20 seconds, air thinned, and light cured for 10 seconds. Next, the adhesive was applied to the lingual surface of the pontic wing and air thinned. A dual-cure luting composite (Variolink^® Esthetic, Ivoclar Vivadent) was then placed onto the facial surface of tooth No. 26, as well as the lingual surface of the wing of the pontic, and the bridge was seated and light cured.

Following bonding of the single-wing composite bridge, the lingual surfaces of teeth Nos. 22 through 27 were etched with phosphoric acid for 10 seconds, rinsed, and air-dried in preparation for splinting. The required length of bondable fiber reinforcement ribbon (Ribbond^®, Ribbond, Inc.) was previously determined using floss and cut with the supplied scissors. Using pliers to handle it, the reinforcement ribbon was then soaked in a bonding agent (Clearfil^™ SE BOND, Kuraray Noritake). To create the splint, a single bead of a flowable light-cure composite (Virtuoso^®, DenMat) was placed along the lingual surfaces of the etched teeth, followed immediately by the fiber reinforcement ribbon, which was carefully tucked interproximally and light cured to secure its position. A final layer of universal composite (TPH Spectra^® ST, Dentsply Sirona) was then placed over the fiber reinforcement ribbon to ensure that no fibers were left exposed and light cured. To complete the splint, any excess fiber reinforcement ribbon was removed, and all areas of composite were smoothed using finishing burs.

The patient verified that the surface of the splint was smooth and comfortable. The facial surface of the pontic was then finished and polished, and teeth Nos. 24 and 26 were slightly recontoured to ensure an esthetically acceptable result as well as to help reduce the risk of secondary occlusal trauma (Figure 11 and Figure 12).

Discussion

Traditionally, the options for creating an anterior pontic when the extracted tooth is not available are to create one with composite resin or to modify a prefabricated denture tooth. The first of these processes requires the use of multiple materials, and both are time-consuming. When immediate tooth replacement is needed, the use of CAD/CAM technology can enable fabrication of a durable and esthetic pontic without many of the challenges of traditional approaches.

Periodontal splinting is a well-established and accepted treatment for the maintenance of compromised teeth in patients with periodontitis. Although splinting does not address the cause of tooth mobility, it can reduce or eliminate mobility and delay or prevent the need for extraction in periodontally compromised teeth. In this case, teeth Nos. 24 and 26 presented with class II mobility and approximately 75% bone loss; however, teeth Nos. 22, 23, and 27 presented with no mobility and approximately 15% bone loss, making the patient an excellent candidate for a periodontal splint to decrease mobility and increase the longevity of teeth Nos. 24 and 26. Studies have shown that splinting improves the retention of mobile teeth while placing them at no greater risk of being lost than non-splinted teeth.⁸ The use of fiber reinforcement ribbon in splinting mobile teeth has been shown to provide great patient comfort, durability, and resistance to fracture as well as the highest flexural strength when compared with other splinting materials, which is an important parameter when splinting teeth.⁹

Conclusion

Managing edentulous spaces in patients with periodontitis can pose many challenges. Periodontally compromised teeth that may be used as abutments in other treatment options can have improved prognoses if stabilized using the splinting technique described in this case. It has been shown that a composite pontic with fiber reinforcement ribbon can act as a provisional or more durable solution, depending on the needs of the case and the patient's desires. With the use of CAD/CAM technology, a strong and esthetic immediate indirect option can be fabricated outside of the patient's mouth in order to minimize chair time. And if the pontic ever debonds and is lost or damaged, a new one can be easily milled from the saved imaging files without requiring any additional chair time.

About the Authors

Lisa D'Affronte, DDS
Clinical Assistant Professor
General Practice Director
Department of Comprehensive Dentistry
University of Maryland
School of Dentistry
Baltimore, Maryland

Zachary T. Palas, DDS
AEGD-1 Program
Fort Sill, Oklahoma

Robert Tigani, DDS
Tigani Dentistry
Washington, DC

Howard Strassler, DMD
Professor Emeritus
Department of Comprehensive Dentistry
University of Maryland
School of Dentistry
Baltimore, Maryland

Figures and Images

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Lisa D’Affronte, DDS

Zachary T. Palas, DDS

Robert Tigani, DDS

Howard Strassler, DMD

Fig. 1

Pre-extraction radiograph showing the periodontal involvement of tooth No. 25, which demonstrated class II mobility and was ultimately deemed hopeless. Note the severity of the vertical bony defect at the mesial aspect.

Fig. 2

Pre-extraction retracted frontal photograph showing the facially positioned tooth No. 25.

Fig. 3

Pre-extraction mandibular occlusal view.

Fig. 4

Post-extraction radiograph of the tooth No. 25 site exhibiting the severe periodontal involvement of teeth Nos. 24 and 26.

Fig. 5

Post-extraction smile photograph showing the tooth No. 25 space.

Fig. 6

Post-extraction occlusal view highlighting the limited restorative space at the tooth No. 25 site due to crowding. Note that the failing restorations on teeth Nos. 18, 20, and 21 that were visible in the pre-extraction occlusal view have been removed and replaced as a part of the patient’s overall comprehensive treatment plan.

Fig. 7

Digital scan of the mandibular stone model that was created after the extraction of tooth No. 25.

Fig. 8

View of the digital design of the single-wing composite bridge on the model.

Fig. 9

View of the digital design of the single-wing composite bridge on the model in occlusion with the maxillary arch.

Fig. 10

Milling preview of the single-wing pontic oriented in the selected composite block.

Fig. 11

Posttreatment smile photograph with the single-wing bridge and fiber-reinforced composite splint in place duplicating the original esthetics of tooth No. 25.

Fig. 12

Posttreatment occlusal view.

Lisa D’Affronte, DDS

Lisa D’Affronte, DDS

Zachary T. Palas, DDS

Zachary T. Palas, DDS

Robert Tigani, DDS

Robert Tigani, DDS

Howard Strassler, DMD

Howard Strassler, DMD