this study is aimed to evaluate and compare the pulp response to ACTIVA BioACTIVE Base/Liner and MTA as pulpotomy medication in primary teeth.

Pulpotomy is an endodontic technique that involves amputating the coronal pulp and covering the residual root pulp with a clinically effective pulp medicament that is bactericidal, capable of forming a biological barrier and allows the physiological root resorption until primary tooth exfoliation. In primary dentition, pulpotomy therapy is divided into three types based on the treatment goals: devitalization (mummification), preservation, and regeneration. Formocresol is the benchmark for pulpotomy treatment in primary teeth. Buckley first used it to treat nonvital permanent teeth in 1904, and it later became a common pulpotomy medication for primary teeth primarily because of its superior clinical success and simplicity of use . However, toxicity, mutagenicity, and carcinogenicity issues posed by the possible systemic spreading of FC molecules via the root canals raised concerns on its use ; as a result, a more biocompatible, nontoxic medication was required.

Biocompatible and bioactive materials containing calcium silicate have become increasingly common in paediatric dentistry in recent years because of their properties, which include stimulation of pulp cell regeneration, re - routing of the inflammatory response, and improving the healing ability of the remaining vital pulp . Mineral trioxide aggregate (MTA) was developed and implemented as a root-end filling at Loma Linda University in California, USA, in 1993; its physical and chemical properties were identified by Torabinejad et al ., in 1995. MTA is a chemical compound composed of tricalcium silicate, dicalcium silicate, tricalcium aluminate, calcium sulphate dehydrate, gypsum, and bismuth oxide . It hydrates to form a colloidal gel with a pH of 12.5, equivalent to that of calcium hydroxide . Moreover, it takes 3 to 4 hours to set with a compressive strength of 70 Mpa after setting, which is comparable to Intermediate Restorative Material (IRM) . MTA is a biocompatible substance that seals better than amalgam or zinc oxide eugenol (ZOE) [30-32] also, it retains pulp vitality and induces repair as it comes into contact with dental pulp or peri-radicular tissues. MTA has been thoroughly examined clinically and radiologically, as well as compared to other pulpotomy medicaments, and it has been reported that MTA should be considered the new gold standard for pulp-capping therapy. On the other hand, MTA has some drawbacks, including difficulty in manipulation, a long setting duration, a high cost, poor mechanical properties, poor adhesion to dental tissue and tooth staining .

Several recent calcium silicate-based materials have been developed in order to alleviate MTA's drawbacks. ACTIVA BioACTIVE Base/Liner, a BioACTIVE glass-incorporated light-curable pulp capping material, was recently introduced in 2014 as a "light-cured resin-modified calcium silicate" (RMCS) claiming composite's resilience, aesthetics, and physical properties, as well as improved calcium, phosphate, and fluoride release when compared to glass ionomer . It comprised of a diurethane and methacrylate-based monomer with a modified polyacrylic acid and polybutadiene-modified diurethane dimethacrylate as well as BioACTIVE glass as a filler . ACTIVA has three setting reactions: it cures with low intensity light for 20 seconds per layer and has both glass-ionomer (acid-base reaction) and composite self-cure setting reactions. The bioactivity of ACTIVA BioACTIVE products is dependent on a process in which the material reacts to pH cycles and actively participates in the release and recharging of considerable amounts of calcium, phosphate, and fluoride . Theses mineral components are concerned with promoting the development of mineralized hard tissue also, they promote the creation of a connective apatite layer and the development of a seal at the material-tooth interface .

Inclusion Criteria:

• Healthy & cooperative child
• No history of spontaneous pain
• No pathologic tooth mobility
• Normal gingival and periodontal condition
• Absence of furcal/periapical radiolucency

Exclusion Criteria:

• Uncooperativeness of child and/or parents
• Unrestorable tooth
• history of spontaneous pain
• Percussion sensitivity

protocol & conclusion

for 1 month