file optimizationdigital dentistry library creationkey switch maintenancescanhead failuremachine upgrade optionsintermittent failurescanner downtime reductionhigh speed handpiece servicingoptical window repairForm 4 alternativeexocad crash fixPropex Pixi battery replacementtroubleshoot Owandy intraoral X-rayGENDEX sensor servicescanner maintenance urgency
