Clinical and Radiographic Evaluation of Injectable Composite Versus Packable Composite in Restoring of Primary Molars

This randomized clinical trial aims to compare the clinical and radiographic performance of injectable composite versus packable composite in restoring cavitated primary molars in children aged 4-8 years.

Study Purpose

To determine whether injectable composite performs as well packable composite in Class II restorations in primary molars.

Study Design

Type: Randomized clinical trial

Sample: 64 primary molars (32 per group)

Allocation: 1:1 using concealed envelopes

Group I (Experimental group): Injectable composite (Beautifil Flow Plus X F00, Shofu, Japan) Group II (Control group): Packable composite (Beautifil II LS, Shofu, Japan)

Follow-up: Clinical at 3, 6, 12 months

Radiographic at 0, 6, 12 months

Location: Pediatric Dentistry Clinic, Cairo University

Outcome Measures

Primary Outcome Clinical Performance (FDI Criteria):

Functional: marginal adaptation, fracture, proximal contact, occlusion, wear

Biological: caries at margins, hard tissue defects, sensitivity, pulp status

Esthetic: texture, staining, color match

Secondary Outcome Radiographic Performance:

Presence/absence of voids

Marginal integrity on bitewing radiographs

Rationale

Injectable composites may offer:

Better cavity adaptation

Easier handling

Shorter chair time (important in pediatric dentistry)

Packable composites offer:

Higher strength and wear resistance

The study investigates whether injectables can match or outperform packables clinically.

Hypothesis

Null hypothesis: There is no difference between injectable and packable composites in clinical and radiographic success.

Intervention The principal investigator ES will carry out all treatment procedures, and the patients will be randomly assigned to any of them.

For both groups:

1. Informed consent from participating children parents.
2. Baseline records photographs, percussion test, periapical radiograph and personal data collection (Appendix 1: Diagnostic chart).
3. Diagnostic chart with personal, medical and dental history will be filled (Appendix 1: Diagnostic chart).
4. Allocation (concealed by withdrawing a sealed opaque envelope containing Four-folded numbered papers containing the type of restorative material that will be used then writing the patient name and I.D. on it and will be opened after performing the cavity).
5. Clinical examination will be performed to assess the clinical inclusion criteria.
6. Preoperative and Postoperative photographs will be taken.
7. The radiographic examination will be performed by taking a periapical x-ray using (bitewing technique) to assess the inclusion criteria. The preoperative radiograph will serve as a reference for the follow-up radiographs.
8. Administration of local anesthesia at the side of the affected tooth.
9. Application of rubber dam for isolation, then caries removal procedure will be performed using a sterile round-end bur in a high-speed handpiece
10. After cavity preparation, conditioning of the tooth will be done using 35% phosphoric acid for 30 seconds for enamel and 15 seconds for dentin. Then, after rinsing the acid etch with water for 10 seconds, bond will be applied to the tooth using a bond brush and then cured for 5 seconds.
11. The restorative material will be placed in the cavity and will be cured for 20 seconds per increment for the intervention group and for 20 seconds for the control group (17).
12. The last step is to finish and polish the restoration material with abrasive rubber tips using the KENDA C.G.I polishing system (Coltene, Switzerland) (
13. Clinical assessment will be done after each visit using FDI criteria to assess the clinical performance of each restoration in the three domains (biological, functional and aesthetics) and radiographic assessment will be done for 0, 6, and 12 months using periapical bitewing x-ray.

Sample size calculation:

Data will be analyzed using Medcalc software, version 22 for Windows (MedCalc Software Ltd, Ostend, Belgium).

Categorical data will be described as frequency and percentage. Intergroup Comparisons between categorical variables will be performed using the chi-square test, while intragroup comparisons within each intervention will be performed using Cochran's Q test followed by pairwise multiple comparisons.

A p-value less than or equal to 0.05 will be considered statistically significant, and all tests will be two-tailed. Statistical power of the study will be set at 80% with a 95% confidence level.

The sample size was calculated based on a previous study by Inthihas et al in 2019, in which the success rate of proximal giomer restorations in primary molars was 94.1% after 12 months (17).

By implementing a two tailed Z test for the difference between two independent proportions with an alpha level of 5% and a power of 80%.

The minimum sample size needed was 28 per group in order to detect a difference of 30%.

Sample size was increased by 15% to compensate for possible dropouts to reach 32 teeth per group. Sample size was performed using G*Power version 3.1.9.2 for windows.