Out of curiosity, are you only using a stick-on thermometer, and not a digital probe thermometer or a temperature gun? The reason I'm asking is that you only gave 2 temperatures, so my guess is that you are only using a stick-on thermometer, and the temperature you gave of 110 (which is the highest temperature that he should have in his enclosure anywhere) is not actually his Basking Surface Temperature at all, but is rather the Hot Side Ambient (air) Temperature. This is most likely the reason he is hiding in his hide or under his cave all the time.
Those stick-on thermometers are extremely inaccurate, and when tested are usually off by between 10-20 degrees. So if his Hot Side Ambient Temperature is reading at 110 degrees on a stick-on thermometer (the Hot Side Ambient (air) Temperature for a dragon should only be between 88-93 degrees maximum), not only is the Hot Side Ambient Temperature WAY TOO HIGH, but the actual Basking Spot Surface Temperature is going to be even hotter than 110 degrees (which may actually be closer to 120 degrees since those stick-on thermometers are usually consistently off by quite a bit). You cannot measure his actual Basking Spot Surface Temperature with a stick-on thermometer anyway, even if they were accurate, which they aren't, and this is dangerous for a couple of reasons, one being you can't know what his Basking Spot Surface Temperature is at all, and also because any temperature over 110 can be very harmful to lethal.
A baby or juvenile bearded dragon should have a Basking Spot Surface Temperature between 105-110 degrees, and usually at around a year old they like it a bit cooler, between 100-105. The Hot Side Ambient Temperature should be between 88-93 degrees maximum, and the Cool Side Ambient (air) Temperature should be between 75-80 degrees maximum, so he always has a place considerably cooler than the Hot Side or the Basking Spot to go.
So my guess is that his entire enclosure is far too hot, as if the Hot Side Ambient is 110, his Basking Spot is going to be higher than 110, and his Cool Side Ambient is going to be much higher than 80. This is why he's hiding and not wanting to do anything, temps that are that high can cause extreme lethargy, no appetite, dehydration, excess sleeping, etc.
You need to go to Petco or PetSmart and buy a $10 Digital Thermometer that has a Probe on a wire, or a Temperature Gun. Those are the two thermometer choices that are both extremely accurate, and will allow you to actually find out what the Surface Temperature of his Basking Spot is by placing the probe directly on the Basking Spot where he sits to bask, BE SURE TO ALLOW THE PROBE TO SIT FOR AT LEAST 20-30 MINUTES BEFORE READING THE TEMPERATURE, and after 20-30 minutes look at the temperature reading, and if it has stopped going up then that's your Basking Spot Surface Temperature. Depending on how much higher it is than the correct range of 105-110 degrees you'll need to either raise your basking light up or go to a lower wattage basking bulb all together (REMEMBER THAT YOU CANNOT MOVE HIS BASKING SPOT AWAY FROM HIS UVB TUBE, SO THE ONLY ADJUSTMENT YOU CAN MAKE TO LOWER THE TEMPERATURE IS TO MOVE ONLY THE BASKING LIGHT UP AND AWAY FROM THE BASKING SPOT). Once you figure out what you need to do to get his Basking Spot Surface Temperature between 105-110 degrees, then move the probe of the digital thermometer off of the Basking Spot and down into the Hot Side of the tank by attaching the Suction Cup that comes attached to the wire just below the probe, and attach the Suction Cup to the Glass on the Hot Side, about 1-2" above the floor. Let the probe sit there for 20-30 minutes and read the temp again, and if it has stopped going down, then that's you Hot Side Ambient Temperature. Then move the probe to the opposite side of the tank, to the Cool Side, attach the Suction Cup to the glass of the Cool Side about 1-2" above the floor, allow the probe to sit for 20-30 minutes, and read the temp, and make sure that it has gone down enough with the changes you have made to the Basking Bulb height or wattage to get the Cool Side Ambient Temperature between 75-80 degrees maximum...