Patients who are willing to participate in the study and attend follow-up appointments
bruxism
RECRUITMENT, CARIES
The criteria for exclusion were:
Patient with lack of compliance (Grade 1 and 2 patients according to Frankl behavior rating scale).Patients with partially-erupted permanent first molars, or fully-erupted ones without an antagonist.Patients whose teeth have root canal treatment or deep dentin caries with the risk of iatrogenic pulp exposure.Patient with nickel allergy, bruxism and/or deep bite.The recruitment and flow diagram of patients is presented in Fig. 
The recruitment and flow diagram of patients