This article is a reprint by permission from Ormco. It appeared in "Clinical Impressions" Vol. 5, No. 4, 1996.  Reprinted here with color images, we felt that it was worth revisiting.

The Resin-Bonded Pontic
by Richard E. Boyd, D.M.D., M.S. Columbia, South Carolina

en francais

he treatment of congenitally missing teeth is a common problem

facing the orthodontist. Approximately 7 percent of the population has some pattern of missing teeth. Mandibular second premolars are the most frequently missing teeth while maxillary lateral incisors are second-most. Obviously, any anterior tooth presents an esthetic challenge, but a maxillary anterior tooth is especially critical. It is the missing maxillary lateral incisor(s) that I would like to discuss.

The etiology of missing teeth is unclear. Genetics appears to play a major role, even though only 10 percent of all patients studied have a family history of missing teeth.

Treatment
Treatment of congenitally missing maxillary lateral incisors varies greatly. The occlusion, facial profile, patient desires and the treating doctor's preference determine the final mechanotherapy. Missing teeth present both a functional and cosmetic concern. As a result, any treatment decision should be reached by the team of patient, parent, orthodontist and restorative dentist.

In the past there have been several approaches to treatment. The first is to substitute maxillary cuspids for the missing laterals, followed by enameloplasty combined with bonding, to eliminate bridges (Figure 1). Second are traditional bridges (Figure 2). Third is to make Maryland bridges with acid-etched metal wings (Figure 3), and fourth, implants to replace the missing laterals (Figure 4).

Traditional Cuspid Substitution


Fig. 1A. Cuspid substitution after
enameloplasty and bonding.


Fig.1B. Final facial photo.



Traditional Three-Unit Bridges


Fig. 2A. Preparation for three-unit
bridges.


Fig.2B. Traditional three-unit bridges.



Maryland Bridges


Fig. 3A. Missing laterals prior to
Maryland bridges.


Fig. 3B. After cementation of
Maryland bridges.


Fig.3C. Facial view.


Fig. 3D. Palatal view.



Implants with Crowns


Fig. 4A. Panoramic X-ray with implants in place.


Fig. 4B. Implants prepped for crowns.


Fig. 4C. Final cementation of crowns over implants.

Resin-Bonded Pontic
A recent innovation in restorative treatment of missing lateral incisors is the resin-bonded pontic. This method provides a very conservative approach by creating minimal dimpling of the contiguous teeth, barely breaking the enamel-dentin junction. The surface area is equivalent to that of a BB** (Figure 5). In addition to the conservative nature of this restoration, the all-porcelain pontic and wings provide for an exceptional esthetic result (Figure 6). Lastly, to add a more natural look, the tissue is "scooped out" upon placement of the final restoration so that the pontic appears to come right out of the tissue (Figure 7). It is important to do this on the model in the lab prior to construction of the pontic - not in the mouth - before insertion. The healing gingiva recontours nicely around the final restoration (Figure 8)


Resin-Bonded Pontic


Fig. 5A. Lingual view of BB-size preps
prior to electrosurgery to remove tissue
and before bonding of pontic.


Fig. 5B. Pontic bonded in place.


Fig. 6A. Facial view of pontic



Fig. 6B. Lingual view of pontic on model.
Note wing extensions.
(outline enhanced for clarity)


Fig. 6C. Facial view of ceramo-glass pontic.


Fig. 7. Model preparation of tissue area
in lab, an important step for aesthetics.


Fig. 8A. Resin-bonded pontic a few weeks
following placement.


Fig. 8B. Close-up of pontic.
Note appearance of pontic at gingival margin.

An even newer option is belleGlass HP,™*** a conservative, strong (polymer glass) and esthetic resin-bonded pontic. It is the latest esthetic restorative and provides high flexural strength, affording the best of both porcelain and composite restorations. The superior color depth, light absorption and enamel-like luster make the belleGlass HP restoration virtually disappear in the mouth. The material is cured under high-pressure nitrogen at 280°F and wears at a rate of only 1.2 micrometers per year, but it will not destroy natural opposing teeth.

Conclusion
While there are many options for the practitioner today, dental materials continue to improve and provide even more options for our patients. These conservative, strong, esthetic options offer an alternative to prepping for full porcelain-fused-to-metal three-unit bridges or the use of implants on an adolescent teen. This advancement in dental materials, coupled with good restorative work and a team approach to management of this problem, provides the best option available for our patients.

* IPS Empress is a ceramo-glass material from Ivoclar Williams, Amherst, New York. ** Special thanks to Dr. Malcolm Gordon, Columbia, South Carolina, for providing some of the clinical slides of the restorative process. *** belleGlass HP is a polymer-glass material from belle de st. claire, Orange, California.

Dr. Richard Boyd is in private practice in Columbia, South Carolina. He has authored many articles and has been a featured speaker at the AAO.