Once either the Pennsylvania Superior Court or the Pennsylvania Commonwealth Court renders a ruling on the appeal, the party that lost on appeal could request that the Pennsylvania Supreme Court review the case by filing a petition for allocatur. This petition asks the Supreme Court to hear the case because it presents a novel issue of law.
However, the Supreme Court only accepts a very small number of appeals each year. They have discretion as to whether or not to take a case and the vast majority of the time the Supreme Court will decline the previous case. This means that the ruling of the appeals court is typically the final ruling.