The goal of this observational study is to to evaluate the periodontal condition around metal-ceramic crown. The main question to be answered is: whether the metal-ceramic crown is the cause of gum changes? The study offers to involve patients who have received single metal-ceramic crown and have kept the same tooth intact on the other side of the mouth.The condition of the gums around the crown will be compared with the corresponding natural teeth on the oposite side of the mouth. Clinical parameters such as plaque accumulation, bleeding on probing, periodontal pocket depth and gingival recession will be evaluated. All procedures are part of routine dental examination. Participants: patients who have previously received treatment with metal-ceramic crowns and agree to undergo a gingival examination.