With the advent of accurate imaging technologies and CAD/CAM technologies, general dentistry has seen great advances in our treatment options and recommendations for our patients. This is not more evident than in the ability to include orthodontic treatments in the development of treatment plans.
Many times the dentist is seeking to create a restoration of the patient’s upper anterior dentition with modern ceramic materials. The underlying problem of malposition, wear, overload or limited envelope of function cannot always be managed without addressing the opposing dentition. Failure to take into account the lower anterior dentition can result in reduced life expectancy of the new restorations, perpetuation of wear or collapse of the anterior segment, and/or poor guidance with resultant overload or imbalance of posterior forces.
By including orthodontic options such as Invisalign, the general dentist can effectively deal with many of the underlying issues that might possibly contribute to early failure, ongoing wear, or overloaded envelope of function.
As the anterior segment is restored, several principles are able to be considered in addition to the aesthetic arrangement of the upper anterior teeth if Invisalign treatment is added to the plan.
- Overbite and overjet
- After the upper anterior incisal edge position is designed for aesthetics, then the lower incisor position can be designed with specific overbite and overjet.
- This can establish a more normal anterior envelope of function.
- Overerupted anterior segments can be intruded to reduce a deep overbite.
- Anterior coupling
- The anteriors can be coupled to provide incisal guidance and if the lower anteriors are aligned correctly, protrusive forces can be distributed evenly.
- Cuspid guidance can be established or enhanced.
- By establishing excellent guidance, working and balancing interferences are reduced or eliminated
- This will minimize the amount of posterior force overload
- This will minimize the amount of posterior equilibration needed
- Arch form development
- Arch forms can be widened somewhat to create a more normal broad smile.
- Widening the arch form can also provide much needed space in a crowded dentition.
- Lower aesthetic enhancement
- Many patients show their lower anterior teeth especially when speaking
- Provides a more complete smile enhancement
All of these principles are easily developed in the Invisalign plan and prescription.
Case example
A female patient in her early forties presents with a history of regular dental care and a chief complaint of an unattractive smile.
Examination revealed a narrow upper and lower arch with multiple areas of recession and abfraction lesions. There was a history of class V lesions some of which had been restored with composite. Posterior teeth had been restored and were nicely interdigitated. She had a reverse smile line with upper anterior teeth flared and crowded. The lower anterior segment was also crowded and overerupted due to a slight class II occlusion. The upper anterior teeth were chipped, worn, and discolored. The lower anterior teeth also showed signs of wear and discoloration. The lower arch demonstrated steep curves of Spee and Wilson with weak cuspid position and poor cuspid guidance.
The treatment planning included several options including restoring upper and lower 10 anterior teeth, or restoration of the upper 10 anterior teeth with no change to the lower arch. The first option would have allowed for correction of the chief complaint and most of the conditions listed above, however, the cost was prohibitive for the patient and was not conservative in the management of the patient’s teeth. The second option was also somewhat of a stretch financially for the patient, but perhaps doable. It did not include stabilizing the lower anterior crowding, which was destined to get worse. It did not allow for control of the overbite, overjet, curves of Spee and Wilson, or the narrow arches. It also would not ideally create the guidance necessary for control of functional interferences.
The third treatment option included Invisalign orthodontic treatment to be followed with four upper anterior ceramic restorations. This treatment was more affordable and allowed for more complete control of the malpositioned teeth, arch form, guidance, and decent smile enhancement. In addition, this option was much more conservative with respect to tooth preparation and number of teeth to be restored.
The patient accepted this plan and treatment was accomplished as planned. The patient was placed in clear removable retatiners during the restorative phase of treatment and new retainers were fabricated after the anteriors were restored. The patient then received minor occlusal adjustment to finalize the force balance and guidance.
In summary, by incorporating the Invisalign process into case planning, often the patient can experience a more comprehensive plan and approach to treatment. Also the dentist can expand the scope of esthetic treatment to include the lower anterior teeth in order to enhance function, aesthetics and maximize the longevity of the restoration.
