This study is a randomized, 12-month follow up clinical trial. According to sample size calculation, ten patients will be selected in conjunction with departments of Pedodontics and Crowns & Bridges. The study will be conducted in accordance with the principles of the Research Ethics Committee, Faculty of Dental Medicine for Girls, Al-Azhar University, Egypt.~The purpose of the investigation and the clinical procedures of this study will be explained to the parents and children. A written informed consent form will be signed from patient guardians and obtained prior to study initiation. The inclusion and exclusion criteria are established as the following;~Inclusion criteria~Children of 5-9 years old.~The children have at least 2 pulpotomized primary molars with no clinical signs & symptoms or periapical pathosis.~Presence of an intact contralateral primary molar as a control.~Willingness to participate and to continue with the follow up appointments.~Clinical and radiographically confirmed dental caries extending to the middle third of dentin.~Presence of teeth in opposite arch with normal occlusion.~Exclusion criteria~Children with systemic health problem.~Children with periodontal disease.~Children with unilateral chewing habit or allergic to local anesthesia.~Presence of parafunctional habit.~Clinical procedure;~Patient selection and education; The participating children will continue with their routine dental appointments in the undergraduate training clinic. Before beginning, children, along with their parents will receive a standard oral hygiene education by an undergraduate student through brushing demonstration on a model. Parents will be warned when signs of gingival inflammation are present, or plaque control is inadequate.~Samples grouping and teeth preparation:~Forty primary molars will be included in the study. Twenty decayed teeth will be restored with crowns (10 with custom-made ZrCs and 10 with prefabricated ZrCs), and the other twenty intact contralateral teeth will be evaluated as the controls (10 molars will be the controls for custom-made ZrCs and 10 molars will be the controls for prefabricated ZrCs). Preparation of the crowns will be performed under local anesthesia, according to manufacturers' instructions with the following guidelines; 1-2mm occlusal reduction, 0.5-1mm axial reduction, and a chamfer finish line will be established 0.5-1mm subgingivally.~Impression taking and temporization:~After preparation, rubber-base impressions will be taken for the teeth specific for custom-made ZrCs. Then SSCs will be temporarily cemented over the prepared teeth till the next appointment.~Try-in and cementation of ZrCs:~SSCs will be removed and the custom-made and prefabricated ZrCs will be tried in and permanently cemented.~Follow-up visits:~The participants will be recalled for evaluation after a baseline and at 1, 3, 6 and 12 months.~• Evaluation methods:~The periodontal health will be assessed using the plaque index (PI) and the gingival index (GI).~The clinical success of the crowns will be assessed in terms of crown retention, marginal adaptation, crown contour, fracture, stain resistance, opposing tooth wear and tooth exfoliation.
Background: Do construction methods of pediatric zirconia crowns affect the periodontal health and clinical performance of badly decayed primary molars? The question asked by many practitioners.~Purpose: to compare the periodontal health and clinical performance of primary molars restored with custom-made and prefabricated zirconia crowns. Hypothesis is the performance of primary molars restored with custom-made zirconia crowns will be equivalent to those restored with prefabricated zirconia crowns.