Introduction

The knowledge about the envelope of function and its influence on the TMJ and lifelong incisal tooth wear is essential when treating your patients holistically. It is furthermore very easily corrected with aligners.

Initial Situation

The patient presented with the following symptoms: He expressed the feeling of not having enough space for his mandible in the sagittal and was always pushing his lower arch against his upper incisors. This was making him feel

uncomfortable. On palpitation of his M. masseter, hypertrophy and hardness could be detected. The mouth opening was down to 38 mm actively and 42mm passively. There were static contacts in the anteriors in CR. The inclination of the upper incisors was more than 90° to the occlusal plane. There was slight incisal wear on the upper middle incisors. Additionally, the lower incisors were protruded and rotated due to tertiary crowding.

Procedure/Treatment planning

We began by scanning our patient with the TRIOS 4 intraoral scanner. We furthermore took 8 orthodontic photos. These were analyzed under orthodontic, functional and aesthetic aspects [1-4] and were uploaded into the ClearCorrect Portal where a treatment plan was suggested a few days later.

The main aim was to upright the upper incisors – especially to procline the upper right middle incisor, creating space for the lower arch to autorotate into a more comfortable position. At the same time giving the upper premolars some buccal root torque to expand the upper arch and to create an esthetic buccal corridor, simultaneously giving the lower arch more space in the transversal dimension [4] (Figure 1).

Figure 1: Photo status before treatment.

Orthodontic Procedure

The first aligners were fitted. There were altogether 19 aligner sets for the first phase of the treatment. Extensive IPR of 2.4 mm was needed in the lower arch to ensure enough overjet by retrusion and intrusion of the lower anteriors at the end of treatment. The upper arch needed no more than 0.5 mm to prevent black triangles. Vertical engagers were placed in the upper and lower arch to enable the rotation of 14,13,21,24,35,33,31,32 and to enable buccal torque of the incisors and premolars to upright the upper and lower arch. Only one horizontal engager was needed to aid in intrusion of 31 (Figure 2).

Figure 2: Application of IPR and engagers.

After 19 aligners, we scanned for a revision to create some overcorrection. A further 11 aligners were planned and applied by the patient. To create some more bodily movement, a horizontal 3mm x 1mm engager was placed on 11. A further 0.9mm of IPR was applied to the lower anteriors to create more overjet and 0.3mm was applied between the upper middle incisors to reduce a residing black triangle. The revision of an aligner case should not be perceived as failure but as a great chance to get the 100% orthodontic outcome for you and your patient.

Furthermore, a bleaching was applied to create a more aesthetic result [5,6].

Treatment Outcome

During treatment the patient already remarked on how much better his bite felt. By lifting the posterior bite by 1.52 mm due to the thickness of the aligner material, the patient immediately felt relief. After revision the patient had a perfect envelope of function and all 3 golden rules of occlusion as described by J.L.Ruiz [7,8].

1. Even static contacts in CR

2. Immediate disocclusion of posteriors in protrusion

3. Free Envelope of Function

were implemented, giving him the full function whilst relieving his TMJ and the M. masseter [9]. At the same time the upper incisors were protected from excessive tooth wear [7]. The active mouth opening went up to 42mm. Passively the patient could achieve 50mm (Figures 3-5).

Figure 3: Photo status after treatment.

Figure 4: Treatment plan before and after of the Envelope of Function.

Figure 5: Treatment plans before and after of the incisal inclination and the resulting restricted envelope of function and its correction.

Findings/Discussion and Conclusion

As Tif Quereshi and J.L. Ruiz [7,8] have quite explicitly described, the envelope of function cannot be ignored. When adhering to this principle, the TMJ and the masticators can be spared. The understanding of it also helps us, when applying composite to incisors when doing edge bonding, but also when doing extensive prosthodontic treatment. An aligner therapy before incisal restoration can help these very same to last a life time, whereas in a younger patient, it can prevent the tooth wear leading to the need for such treatments.

References

1. Rufernacht CR (1990) Fundamentals of esthetics. Chicago: Quintessence.
2. Tjan AH, Miller GD, The JG (1984) Some esthetic factors in a smile. J Prosthet Dent 51: 24-28. [Ref.]
3. Vig RG, Brundo GC (1978) The kinetics of anterior tooth display. J Prosthet Dent 39: 502-504. [Ref.]
4. Nascimento DC, Santos ER, Machado AW, Bittencourt MAV (2012) Influence of buccal corridor dimension on smile esthetics. Dental Press J Orthod 17: 145-150. [Ref.]
5. Basting RT, Rodrigues AL jr, Serra MC (2003) The effects of seven carbamide peroxide bleaching agents on enamel microhardness over time. J Am Dent Assoc 134: 1335-1342. [Ref.]
6. Al-Qunaian TA (2005) The effect of whitening agents on caries susceptibility of human enamel. Oper Dent 30: 265-270. [Ref.]
7. Qureshi T (2013) The concept of Progressive Smile Design. Int J Cos Dent 4: 1-10.
8. Ruiz JL (2010) The three golden rules of occlusion. Dent Today 29: 92-93. [Ref.]
9. Williamson EH, Lundquist DO (1983) Anterior guidance: its effect on electromyographic activity of the temporal and masseter muscles. J Prosthet Dent 49: 816-823. [Ref.]

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Article Information

Article Type: SHORT COMMUNICATION

Citation: Komischke R (2025) Correcting the Envelope of Function with Clear Correct Aligners. Int J Dent Oral Health 11(2): dx.doi.org/10.16966/2378- 7090.431

Copyright: ©2025 Komischke R. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Publication history: 

Received date: 17 Mar, 2025

Accepted date: 24 Mar, 2025

Published date: 28 Mar, 2025