Aims: to assess the different histologic reactions in dentin-pulp organs in the pulp of mongrel dogs after stimulation with Low-Level Laser (LLL), mineral trioxide aggregate (MTA), and TheraCal light-cured (LC) as capping therapies and compare it with the conventional calcium hydroxide (Ca(OH)) cement material. Subjects and Methods: Eight male mongrel dogs weighing 10-15 kg and 12-18 months old were chosen for this study. The pulp exposure was done via the preparation of a class V cavity on the buccal surface of the premolar teeth. In each doge, the premolar teeth were involved and assigned to four different groups based on the treatment procedure (group 1: LLL; group 2: MTA; group 3: TheraCal LC; and group 4; Ca(OH). The histological reactions at the site of exposure and the mid-region (including odontogenic zones, pulp cores, and supposed tertiary dentin formation) were recorded at 3 different follow-up periods (7, 14, and 42 days). Results: The histological finding showed different histological reactions in the dentin-pulp organs at the site of exposure and the mid-region in response to the different capping materials at different follow-up periods with a higher positive effect with Laser, and MTA followed by TheraCal LC, and Ca(OH) at different follow-up periods.Conclusion: The use of Laser, and MTA as pulp-capping therapies has a considerable positive histological reaction on the dentin-Pulp organs when compared with TheraCal and Ca(OH).

Objectives: This immunohistochemical study was performed to assess the different immunohistochemical activities in dentin-pulp organs in the pulp of mongrel dogs after stimulation with low-level laser (LLL), mineral trioxide aggregate (MTA), and TheraCal light-cured (LC) as pulp therapy and compare their effect with the conventional calcium hydroxide (Ca(OH)) cement material. Materials and Methods: A total of 8 male mongrel dogs 12-18 months old and weighing 10-15 kg were selected to be enrolled in this study. Animal choice, administration, surgical protocol, and provision were completed according to regular techniques standards by the Faculty of Veterinary, Cairo University, Egypt. All surgical techniques were accomplished under general anesthesia (GA) in a sterile operating room under aseptic circumstances with restricted isolation. The pulp exposure procedure was carried out through the preparation of a Class V cavity on the buccal surfaces of the animal premolar teeth. In each animal four premolar teeth were involved and allocated to four different groups grounded on the pulp therapy procedure (group I: LLL; group II: MTA; group III: TheraCal LC; and group IV; Ca(OH). The final cavity restoration was glass ionomer cement (GIC). The immunohistochemical analysis was completed following the established methods.