To explain:
Round Trip to Stage — round tripping, temporary proclination of the upper or lower incisors is a useful technique to improve access for IPR. In many cases, it is not necessary to procline the anterior teeth so far forward to perfectly align the interproximal contacts before performing IPR. I will “read” my ClinCheck plan and determine the stage at which the contacts are sufficiently aligned to gain safe access to perform IPR. “Round trip to Stage” indicates at which ClinCheck stage the proclina- tion ends and the IPR begins. This can both significantly shorten treat- ment time by reducing the number of stages, as well as prevent exces- sive proclination, which may lead to gingival recession and/or bone loss.
Amount: U Ant/L Ant/U Post/L Post — fill in the amount and location of the IPR you would like to perform in these fields.
JESSICA’S CLINCHECK LIST
To explain, in Jessica’s lower arch, 0.3mm of IPR will be performed after the lower anterior teeth have been round tripped to stage 13. The lower incisors are not perfectly aligned at stage 13, however the contacts are comfortably accessible.
CLINCHECK TREATMENT PLAN
The patient’s ClinCheck plan (see Image 9-2) indicates the use of 0.3mm of IPR from lower canine to lower canine to create room to re- solve the lower incisor crowding. At the end of treatment, the lower arch is well aligned (see Image 9-3).
Instructions to the technician: Round-trip to improve access for IPR.
THE SECOND USE OF IPR — BOLTON DISCREPANCY
The second indication for IPR is to adjust for a Bolton Discrepancy, also known as a tooth-size discrepancy. When a patient has a tooth-size discrepancy as a result of narrow maxillary lateral incisors, the choices for managing a Bolton Discrepancy are:
- IPR in the lower arch
- Leave space for esthetic build-ups of the narrow maxillary laterals
- Leave space somewhere else in the maxillary arch
In cases where the maxillary lateral incisors are not esthetically too narrow, lower arch IPR is an effective way to normalize the Bolton ratio and help finish with a normal occlusion.
THE THIRD USE OF IPR — REDUCTION OF OVERJET (OR UNDER BITE)
The third use of IPR is to reduce overjet in Class II cases or under bite if the patient is Class III. For example, in a case like the one depicted in image 9-4, the patient presents with a Class III malocclusion. In this case, IPR has been added in the lower arch to create additional space to aid in the retraction of the lower canines and couple them into Class I. This case in particular also has the use of Class III elastics to enhance the correction of the Class III malocclusion. Posterior IPR is being ap- plied to both sides to help couple the canines.
This ClinCheck view (see Image 9-5) is of the patient set up for Class III elastics and lower posterior IPR to retract the lower interior teeth to improve the coupling of the incisors and canines. The final result can be seen in image 9-6.
FOURTH USE OF IPR — REDUCE HEAVY ANTERIOR OCCLUSAL CONTACT
The fourth use of IPR is to reduce the heavy anterior occlusal contact. If you have treated enough patients with Invisalign clear aligners this image (see image 9-7) probably doesn’t look all that unfamiliar. There are cases where we have to manage posterior open bites. In my expe- rience the vast majority of post-anterior open bites are due to heavy anterior contact. In this case IPR was added to the lower arch in order to retract the lower incisors to relieve the heavy anterior occlusal contacts and settle the posterior open bite (image 9-8).