Robust scanner shipments and an increase in Invisalign volumes within the teen segment are expected to have contributed to Align Technology's (ALGN) Q4 performance.
### Instruction: What is the sentiment of this news? Please choose an answer from {negative/neutral/positive}
### Input: Robust scanner shipments and an increase in Invisalign volumes within the teen segment are expected to have contributed to Align Technology's (ALGN) Q4 performance.
### Response: mildly positive