Teen · Narrow Arches
The arch too narrow for the teeth to fit
The upper arch was so narrow that the teeth simply did not have room. The back teeth met in crossbite on both sides, two teeth were stuck below the gum with nowhere to erupt, and one was trying to come through in the wrong place. For a teenager who was unhappy with their smile and could not bite properly, the first job was to make space.
Before treatment — in their own words
The teen’s description: they could not bite properly, one tooth seemed to be growing in the wrong spot on the upper, the teeth were not straight, and they were unhappy with their smile. The “tooth in the wrong place” was an impacted tooth trying to find room in an arch that did not have any.
The clinical picture
Examination showed a severely constricted upper arch with a crossbite on both sides and the upper midline shifted to the left. An upper canine and a lower premolar were impacted, and a couple of back teeth were absent. The crowding and impactions traced back to the same root cause: not enough arch width. Healthy growth and a cooperative teen made this a good candidate for expansion-led treatment.
The plan
A non-extraction Invisalign plan to expand the upper arch, correct the bilateral crossbite, and re-centre the midline — creating the room the impacted teeth needed to come through on their own. The impacted teeth would be monitored as space opened; surgical exposure was held in reserve only if they did not erupt once there was room for them.
The outcome
Over thirteen months the upper arch was widened, the crossbites on both sides were corrected, and the midline came back to centre. With space created, the previously impacted teeth had a path to erupt into. The teen ended treatment able to bite properly, with a straight, fuller smile — and happy with it.
Clinical notes (for dental professionals)
- Diagnosis: Severely constricted maxillary arch; bilateral posterior crossbite; upper midline shift (left); impacted upper canine (23) and lower second premolar (35); missing 37 and 48
- Treatment: Invisalign Comprehensive, non-extraction; maxillary expansion; bilateral crossbite correction; space creation for impacted teeth
- Auxiliaries: Monitor eruption of 23/35; surgical exposure held in reserve if no spontaneous eruption once space established
- Extractions: None
- Duration: 13 months
- Retention: Vivera upper and lower; monitor eruption and arch-width stability