Sedation: insights please

Anyone here had their dog sedated? I'll have mine probably before December during his Nov deworming. My dog has a lot of calculardeposit and before it progresses to periodontal problems (gingivitis or worse, periodontitis) he needs oral prophylaxis and the vet said that he has to be sedated to remove the calculus. Any insights? Is it safe? What should I expect? Any complications? TIA *Panic mom*