Clinical Performance of a Novel Self-cured Resin Composite Compared to a Light-cured Bioactive Resin Composite Restoration in Proximal Cavities of Posterior Teeth: A 2-year Randomized Controlled Clinical Trial
Phase: EARLY_PHASE1
Conditions: Proximal Cavities of Posterior Teeth
Sponsor: British University In Egypt

 
 
 
 
 
 
 
Clinical Performance of a Novel Self-cured Resin Composite 
Compared to a Light-cured Bioactive Resin Composite 
Restoration in Proximal Cavities of Posterior Teeth: 
A 2-year Randomized Controlled Clinical Trial 
 
األداء السريري لمركب راتنج جديد ذاتي
 
التصلب
 
مقارنة بمركب الراتنج ال
نشط حيويا  
  و 
المُصلّب
 
ضوئيا في التجاويف 
البينية
 
لألسنان الخلفية 
: 
دراسة سريرية عشوائية
 
منضبطة
 
لمدة عامين
 
 
 
Protocol submitted to the Operative Dentistry Department 
Faculty of Dentistry, The British University in Egypt 
for partial fulfillment of the requirements for the Master’s Degree in Operative 
Dentistry 
 
By: 
 
Sarah Wael Moustafa Kamel ElSawaf 
Bachelor’s Degree of Oral and Dental Medicine and Surgery 
Faculty of Dentistry, The British University in Egypt 
2021 
Supervised by: 
Main Supervisor: Prof. Dr. Mohamed Fouad Haridy 
Professor of Conservative Dentistry, Faculty of Dentistry, Cairo University 
Head of Conservative Dentistry Department, Faculty of Dentistry, The British 
University in Egypt 
Co-Supervisor: Dr. Ahmed Gamal Saad  
Lecturer of Conservative Dentistry, Faculty of Dentistry, The British University in 
Egypt 
 
Faculty of Dentistry 
The British University in Egypt 
(2025) 
Faculty of Dentistry 
The British University in Egypt 

1 
 
I. Administrative information: 
1. Title:  
Clinical Performance of a Novel Self-cured Resin Composite Compared to a Light-
cured Bioactive Resin Composite Restoration in Proximal Cavities of Posterior 
Teeth: A 2-year Randomized Controlled Clinical Trial 
 
2. Protocol Registration:  
Trial will be registered in www.clinicaltrials.gov  
3. Protocol version:  
Original scientific research (Clinical Trial) 
4. Funding:  
Self- funded. 
5. Roles and responsibilities: 
Name: Sarah Wael Moustafa Kamel ElSawaf 
Email address: Sarah.elsawaf@bue.edu.eg 
Affiliation:  
Demonstrator at the Conservative Department, Faculty of Dentistry, The British 
University in Egypt 
Contacts: 01005505167 
Role: Principal Investigator 
Name: Prof. Dr. Mohamed Fouad Haridy 
Email address: Mohamed.haridy@bue.edu.eg 
Affiliation: Professor of Conservative Dentistry, Cairo University & Head of 
Conservative Dentistry Department, Faculty of Dentistry, The British University in 
Egypt 
Role: Main Supervisor 
Name: Dr. Ahmed Gamal Saad 
Email address: Ahmed.gamal@bue.edu.eg  
Affiliation: Lecturer of Conservative Dentistry, Faculty of Dentistry, The British 
University in Egypt 
Role: Co-Supervisor 

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II. Introduction: 
 
     Dental caries is a complex multifactorial disease characterized by cycles of 
demineralization and remineralization. According to the WHO; dental caries is 
considered as a major public health problem globally affecting almost 2 billion people 
with permanent teeth and 510 million children with deciduous teeth. The prevalence 
of the disease varies across different regions with the higher percentage observed in 
less developed countries. (Warreth) 
       
       The development of dental caries is multifactorial mainly due to the presence of 
4 elements which are: dental biofilm (plaque), fermentable carbohydrates (glucose, 
fructose, sucrose), dental hard tissue and time. Other additional social and 
environmental factors can have a substantial impact on the onset and course of the 
disease. Dietary habits, oral hygiene, salivary flow and fluoride exposure are key 
factors that influence the susceptibility to dental caries. If dental caries is properly 
managed, it is a preventable and reversible disease. (Warreth) 
 
        The occlusal and proximal surfaces are the most susceptible sites for 
demineralization from the acidic byproducts. Proximal carious cavities are carious 
lesions that develop on the smooth surfaces between adjacent teeth often known as 
interproximal surfaces. Due to their hidden location, these cavities are often 
discovered by the aid of radiographic investigation especially bite wing radiographs. 
(Tuculina)  
 
        Resin-based composite (RBC) was first introduced by Dr. Rafael Bowen in the 
late 1950s. The bonding concept along with the invention of the resin matrix; 
bisphenol A-glycidyl methacrylate; known as Bis-GMA in 1962 were both major 
breakthroughs in the modern esthetic dentistry. It quickly became a widely used 
restorative material in modern dentistry especially known for its outstanding aesthetics 
and high mechanical properties. The beginning of RBC was composed of a 
combination of an organic polymer matrix, inorganic filler particles with the addition 
of a coupling agent to enhance bonding and durability. (Ferracane) 
 
       Organic matrix is made of monomers that bond into polymers and form a three-
dimensional network due to polymerization. This network is filled with fillers to 
improve its physical and mechanical properties. Filler materials include either glass, 
quartz particles or fused glass particles. An organic- nonorganic adhesive is added to 

3 
 
the filler particles with the nonorganic end of the molecule tends to bond with the 
fillers and the organic end of the molecule tends to bond with the resin matrix unifying 
the whole chemistry of the composite material. (Milosevic)  
 
         Initially, the traditional dental composite materials were two-part paste systems 
with one containing a peroxide initiator and the other an amine activator. The 2 pastes 
were mixed to result in polymerization in minutes through an auto or self-curing 
process. Later on in the 1970s, light-curing technology was introduced to improve the 
curing process by enabling better handling and manipulation of the material. 
Ultraviolet light was first utilized as an activator for sealants and composites 
containing benzoin methyl ether eliminating the need to mix two pastes and without 
the requirement to place the composite material within a confined working time. 
Ultraviolet light was later replaced by visible light activation technology for curing 
dental composites due to limitation in depth of penetration of UV light as well as risk 
of overexposure to relatively high- intensity UV radiation. (Ferracane)  
 
       In modern restorative dentistry, clinicians always seek solutions that streamline 
procedures, improve outcomes and reduce chair time for patients. Traditional light-
cured composite systems often involve a complex seven step process which includes 
etching, priming, bonding and curing which consumes from 90 to 120 seconds to be 
completed. With each additional step, the risk of technique errors increases, 
potentially compromising the longevity of the restoration. Self-cure composites, with 
their simplified application process, are emerging as a preferred choice over the 
traditional seven-step composite materials. (Logurecio) 
 
       Recently, a novel self-cured bulk-fill restorative material has been introduced into 
the market (Stela, SDI, Victoria, Australia). It is offered in two application forms 
(Stela Automix & Stela Capsule) that is used in combination with a proprietary 
adhesive primer (Stela Primer), which does not require light curing, but it undergoes 
polymerization upon contact with the restorative material in addition to its ability to 
generate minimal shrinkage stresses. (Logurecio) 
 
       Monitoring dental restorations and their performance throughout life is very 
important but uneasy to undertake. Today, the main difficulty is defining accurate and 
reliable indicators that help in making right decisions. The FDI criteria is a 
standardized evaluation system developed by the Fédération Dentaire Internationale 
to comprehensively assess direct and indirect dental restorations. The criteria are 

4 
 
divided into three main domains: aesthetic, functional, and biological, with multiple 
specific parameters under each category to evaluate the restoration's clinical 
performance. (Maillet)  
 
     Therefore; the aim of this randomized controlled clinical trial is to evaluate the 
clinical performance of self-cured composite (Stela, SDI, Australia) in comparison to 
light-cured bioactive nanohybrid composite (Beautifil II, Shofu, Japan) regarding 
proximal contact tightness (F3) and post-operative hypersensitivity as primary & 
secondary outcomes respectively using the FDI criteria in adult population with proximal 
carious cavities in posterior teeth over 2 years. The null hypothesis tested is that in 
proximal cavities of posterior teeth, there is no significant difference in clinical 
performance between self-cured composite and light-cured nanohybrid composite 
restorations. 
 
 
        
 
         
 
          
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

5 
 
III. Review of literature: 
 
      Loguercio et al., 2025 executed an 18-month multicenter double blind randomized 
clinical trial to evaluate the clinical performance of self-cured bulk-fill composite 
(Stela Automix & Stela Capsule, SDI) in comparison to a light-cured bulk-fill 
composite (Filtek One Solventum, 3M). The clinical trial involved 55 participants with 
a total of 165 class I & class II posterior restorations divided into two groups. The self-
cured composite groups received Stela Primer followed by either Stela automix or 
capsule forms while for the light-cured group, the cavities received Scotchbond 
Universal adhesive followed by Filtek One composite. The restorations were 
evaluated at the baseline, after 12 and after 18 months using the updated FDI criteria. 
The results revealed at the 12-month recall, 17 restorations exhibited marginal staining 
with no differences between groups. Regarding surface luster & texture, 30 
restorations were considered clinically good with a significant favoring toward the 
light-cured group and for color match 32 restorations were rated as good with a 
significant result favoring both self-cured composite groups. At the 18-month recall, 
the restorations were rated as good; 22 for surface luster & texture, 27 for marginal 
staining & 40 for color match. The study’s authors concluded that the self-cured bulk-
fill composite (Stela) either in automix or capsule forms showed comparable 
biological and functional performance to the light-cured composite and can be 
considered as a reliable alternative for posterior restorations.  
 
      Guarneri et al., 2025 conducted an in vitro study to evaluate the degree of 
conversion (DC) and polymerization kinetics of a new self-cure bulk-fill resin-based 
composite (Stela Automix, SDI). The study was divided into 7 groups (1) Stela Primer 
(2) Stela Automix (3) Stela Automix exposed to light for 20 secs (4) Stela Primer with 
Stela Automix (5) Stela Primer with Stela Automix exposed to light for 20 secs (6) 
Scotchbond Universal with Stela Automix (7) Scotchbond Universal with Stela 
Automix exposed to light for 20 secs. The real time reaction rates and DC at the bottom 
of 2mm thick specimens were measured at 720 secs after insertion using a 
spectrophotometer. The results concluded that the highest DC rate at 2mm depth was 
achieved when Stela Primer was used in combination with Stela Automix. On the 
contrary, exposing Stela to light for 20 secs didn’t improve the final DC of Stela as 
much as using the Stela Primer. 
 
      Pires et al., 2025 evaluated the bonding performance of a novel self-curing 
restorative system (Stela, SDI) compared with a conventional light-cured resin 

6 
 
composite (Ceram.X ONE, Dentsply Sirona) applied on dentin in both etch & rinse 
(ER) and self-etch (SE) modes. The study’s specimens were divided into 2 groups, 
each group contained of 10 class I prepared cavities in sound dentin and were restored 
using the two materials. Ceram.X ONE group was used in combination with a 
universal adhesive system (Prime & Bond Universal, Dentsply Sirona) while Stela 
group was used along with its adhesive primer. Half of the specimens from each group 
were bonded in ER or SE mode. The specimens underwent micro-tensile bond strength 
testing after 24 hours storage in artificial saliva. The results exhibited that both groups 
in ER mode achieved comparable results (35.8 MPa for Ceram ; 33.6 MPa for Stela). 
On the other hand, in SE mode Ceram group showed significantly lower bond strength 
compared with Stela. The researchers concluded that the new self-curing material 
(Stela , SDI) either used in ER or SE mode represents a promising clinical option to 
provide adequate interfacial adaptation and strong bonding to dentin.  
       
      Laporte et al., 2025 conducted an in vitro study to investigate the performance of 
the new self-curing restorative material (ST: Stela, SDI) compared to two 
conventional light-cured composites (TE: Tetric Evoceram, Ivoclar Vivadent & CM: 
Clearfil Majesty, Kuraray Noritake Dental). The study evaluated compressive 
strength, mineral deposition, porosity and wettability. The data was statistically 
analyzed through one-way and two-way analysis of variance (ANOVA). The results 
revealed higher compressive strength for ST than TE and CM at the baseline and after 
aging while fracture mode analysis showed brittle fractures for TE and CM whereas 
ST fractured in multiple smaller fragments. Wettability testing showed that ST had the 
lowest contact angle compared to TE and CM. Examination by scanning electron 
microscopy revealed cubical-like crystalline formations on ST’s surface indicating 
some level of bioactivity whereas no changes were observed for TE & CM. The 
authors concluded that Stela demonstrated promising results across several parameters 
encouraging it to be a potential candidate for long lasting restorative applications.  
 
      Raghip et al., 2025 executed a double-blind split-mouth randomized clinical trial 
to compare the performance of a bioactive ionic resin restorative (Activa Bioactive-
Restorative) to a conventional bulk-fill composite (Filtek One Bulk-fill Restorative) 
in class I restorations. The clinical trial involved 22 patients who required the 
restoration of bilateral posterior teeth with ICDAS score 5 lesions. Cavity preparation 
included selective caries removal and selective enamel etching protocol followed by 
the adhesive application. A total of 44 restorations were done; 22 used Activa 
Bioactive Restorative and 22 used Filtek One Bulk-fill Restorative. The study was 

7 
 
evaluated by using modified FDI criteria and the follow up was conducted at 3, 6, 12 
and 24 months. The results showed no statistically significant differences were 
observed between groups at the 3,6 and 12 months recalls and both materials showed 
excellent performance across all parameters with no failure or secondary caries over 
the 24-month period. The only significant differences identified were regarding 
surface luster, occlusal wear and anatomical form at the 24-months follow up in favor 
of Activa Bioactive group. The authors concluded that bioactive restorative materials 
exhibit similar performance to a traditional bulk-fill composite showing improved 
long-term stability and can be considered as a strong alternative for posterior 
restorations.  
 
      Loguercio et al., 2024 performed a multicenter double blind randomized clinical 
trial to evaluate the clinical performance of a new chemically cured bulk-fill composite 
(Stela Automix & Stela capsule, SDI) in comparison to a light-cured bulk-fill 
composite (Filtek One, 3M) over a span of 6 months. The clinical trial included 55 
participants (20 males & 35 females) with at least 3 posterior teeth in need of 
restorations. A total of 165 restorations were performed either on class I or class II 
cavities and the participants were evaluated for spontaneous and stimulated post-
operative hypersensitivity (POS) in the base line, after 48 hours, 7 days & finally at 6 
months. Each of the restorations was assessed using the updated version of FDI criteria 
after 6 months. The researchers concluded that chemically cured composites exhibit 
much lower POS and less color mismatch in comparison to a light-cured bulk-fill 
composite after a service of 6 months. The study’s clinical significance showed that 
chemically cured composites appear to be an appealing option for restoring posterior 
teeth. 
 
      Akalin et al., 2023 evaluated the clinical performance of low-shrinkage bioactive 
resin composite employing Giomer filler technology (Beautifil II LS, Shofu, Japan) in 
comparison to a conventional nanohybrid resin composite (Clearfil Majesty Posterior, 
Kuraray, Japan). The authors included a total of 35 participants (18 males & 17 
females) which received randomly 35 pairs of fillings restored with either of the two 
resin composites in class I and II cavities. The restorations were evaluated by two 
calibrated operators 2 weeks after placement (baseline), at 6 months, at 1 and 2 years 
using FDI criteria. Data were analyzed using the McNemar test. In both groups, the 
restorations were rated the best scores (Score 1 & 2) for biological, functional and 
esthetic parameters. The authors concluded that no fracture, endodontic or 
hypersensitivity- related complications were observed. Only one restoration from the 

8 
 
nanohybrid composite group showed a small secondary carious lesion that didn’t 
require intervention and was only monitored and one restoration from the low 
shrinkage Giomer resin composite group showed retention loss. Over the 2-year 
follow up, both the Giomer and the nanohybrid resin composite restorations’ 
performance was clinically acceptable.  
 
      Jacob et al., 2023 conducted an in vitro study to compare the microleakage of two 
low shrinkage resin composite materials in class II cavities using stereomicroscope. A 
total of 34 extracted non-carious teeth were randomly divided into two groups; each 
group included 17 teeth which were restored with either (Filtek Bulkfill, 3M) in 
bulkfill technique or (Beautifil II LS, Shofu) . Class II cavities were prepared followed 
by etching and bonding steps in each tooth and then restored following the 
manufacturer’s instructions. The samples were thermocycled, immersed in 1% 
methylene blue for 24 hours and then finally were sectioned into two halves 
mesiodistally using a diamond disc at low speed. All the samples were examined under 
a stereomicroscope at x10 magnification. The results were examined using Mann-
Whitney U-test which displayed a statistically significant higher mean rank among 
Filtek bulk-fill group. The authors concluded that Beautifil II LS resin composite 
showed less microleakage than Filtek bulk-fill posterior resin composite therefore it 
can be successfully used with increased longevity. 
 
      Pallesen et al., 2015 executed a randomized clinical trial to evaluate the durability 
of 3 conventional resin composites in class II restorations over a span of 27 years. The 
study included 30 participants (25 females & 5 males) with age range 25-63 who 
received at least 3 class II restorations. The 3 cavities were chosen randomly to be 
restored with chemically cured composite (Clearfil Posterior) and two light-cured 
composites (Adaptic II) and (Occlusin). The evaluation was done using modified 
USPHS criteria which were anatomical form, marginal adaptation and discoloration, 
color match and surface roughness at baseline, 2, 3, 10 and 27 years. The results 
showed that the overall success rate was 56.5% (55.2% for Adaptic II group), (63% 
for Clearfil Posterior group) and (51.7% for Occlusin group) with an annual failure 
rate of 1.6%. It was concluded that the chemically cured bulk-fill resin composite 
restorations showed lower failure rates than the light-cured composite restorations. 
 
      Pallesen et al., 2015 evaluated the durability of 3 conventional resin composites 
in class II restorations in a randomized clinical trial over a period of 30 years. The 
study involved 30 participants (21 females and 9 males), each received at least 3 class 

9 
 
II restorations of moderate size. The cavities were restored with 2 chemically cured 
resin composites (P10, Miradapt) and one light-cured resin composite (P30). Bulk 
placement was done for the chemically cured group while the light-cured composite 
resin was inserted in increments. The restorations were evaluated using USPHS 
criteria at baseline, 2, 3, 5, 10, 15, 20 and 30 years. Results showed that the 3 
conventional resin composites showed good clinical performance during the 30-year 
evaluation period but the chemically cured resin composite showed better 
performance and less failure rate than the light-cured composite. 
 
 
       
   
         
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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IV. Objectives: 
 
Aim of Study: 
 
The aim of this randomized controlled clinical trial is to evaluate the clinical 
performance of novel self-cured composite (Stela, SDI, Australia) in comparison to 
light-cured bioactive nanohybrid composite (Beautifil II, Shofu, Japan) regarding 
proximal contact tightness and post-operative hypersensitivity in proximal cavities of 
permanent posterior teeth over a span of 2 years. 
 
 
 
 
PICOTs Elements 
P:    Adult population with class II proximal cavities in posterior teeth 
I:     Novel Self-cured resin composite 
C:    Light-cured bioactive nanohybrid resin composite 
O1:  Proximal contact tightness 
O2:  Post-operative hypersensitivity 
T0:  Baseline (After 1 week) 
T1:  After 6 months 
T2:  After 12 months 
T3:  After 18 months 
T4:  After 24 months 
 
 
Research question: 
 
In proximal cavities of posterior teeth, do self-cured composite restorations provide 
similar or better clinical performance than bioactive nanohybrid light-cured composite 
restorations? 
 
 
 
 

11 
 
V. Materials & Methods 
 
Materials: 
The following materials will be used:  
1) Stela self-cured resin composite (SDI, Australia) (capsule form) 
2) Beautifil II light-cured nanohybrid resin composite (Shofu, Japan) 
3) Beautibond Universal adhesive (Shofu, Japan) 
4) Stela Primer (SDI, Australia) 
Methodology: 
        
          Type of Study:  Randomized Controlled Clinical Trial 
 
A- Participants, interventions & outcomes 
1) Sample size calculation 
The sample size was calculated based on a previous study by T. Toz-Akalin et al., 
2023 in which success rate of nanohybrid composites in proximal posterior 
restorations was 96.6% after 2 years. By implementing a two tailed Z test for 
difference between two independent proportions with an alpha level of 5% and a 
power of 80%. The minimum sample size needed was 25 per group in order to detect 
a difference of 30%. Sample size was increased by 15% to compensate for possible 
dropouts to reach 29 teeth per group. Sample size was performed using G*Power 
version 3.1.9.2 for windows. 
 
Statistical analysis: 
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 95 % 
confidence level. 
 
 
 

12 
 
Study settings: 
The patients will be enrolled from the outpatient clinic of the Conservative Dentistry 
Department, Faculty of Dentistry, The British University in Egypt. 
 
2) Eligibility criteria  
Inclusion Criteria of Participants 
1. Subjects between the ages of 18-47 years old 
2. Primary caries removal 
3. Good or moderate oral hygiene 
4. Free of periodontal diseases (probing depth and attachment levels within normal 
limits/ no furcation involvement/ no mobility) 
5. Cooperative patients who agree to keep the scheduled recall appointments for 
data collection and maintenance 
Exclusion Criteria of Participants 
1. Composite or amalgam removal 
2. Caries extended to the cemento-enamel junction in Class II caries 
3. Grade II or III mobility 
4. Considerable periodontal disease without treatment 
5. Endodontically treated teeth with extensive loss of tooth tissues 
6. Severe wear facets and/or parafunctional activities as clenching or nocturnal 
bruxism. 
7. Subjects who are pregnant during the duration of the study 
8. Subjects with high caries activity 
 
3) Ethical Considerations (Informed Consent) 
The principal investigator will explain the trial to the patients. The operator will 
discuss the interventions and possible harms with patients on the enrollment day, and 
obtain written consent (in Arabic) from the patients willing to participate in the trial, 
and collect it from them. An appendix of the consent form is attached to the protocol. 
4) Recruitment: 
Patients will be enrolled from the outpatient clinic of the Conservative Dentistry 
Department, Faculty of Dentistry, The British University in Egypt after explaining the 
benefits from the research; from which eligible patients will be recruited to fulfill the 
eligibility criteria until the target population is achieved. 
 

13 
 
B- Assignment of interventions 
5) Randomization and Allocation of Participants: 
Sequence generation (Randomization) 
Co-supervisor (A.G) will perform simple randomization; numbers will be generated 
from 1:58 deciding which tooth to receive which intervention in each patient using online 
software available at www.sealedenvelope.com. 
Allocation concealment mechanism 
Sequence generation will be concealed using opaque sealed envelopes. Operator S.W 
will choose between numbers arranged by M.M who will not be involved in any 
clinical phase. 
 
6) Implementation 
M.M will perform sequence concealment. S.W and M.M will carry out allocation 
concealment. 
 
7) Masking/blinding: 
It will be a triple blinded study so that participants, assessors (A.G and M.F), and 
statisticians will be blinded. (The operator could not be blinded because of the difference 
in the application procedures of each restorative material. However, the participants, both 
assessors and the statistician were blinded to the cavity preparation and type of 
restoration.) 
8) Interventions 
Grouping  
Group A):  Intervention: Self-cured resin composite restorations (Stela, SDI, 
Australia) 
Group B): Comparator: Light-cured bioactive nanohybrid resin composite 
restorations (Beautifil II, Shofu, Japan) 
 
Procedural Steps 
Examination and Diagnosis: 
Examination and selection of patients will be done according to inclusion and 
exclusion criteria. Upon confirming medical and dental history, recording patients’ chief 
complaints and dentition, a pre-operative radiograph will be taken using an intraoral 

14 
 
sensor to detect proximal caries and evaluate it against the inclusion criteria. Clinical 
examination will be done under 4.5 x magnification loupes and dental unit LED light 
using front-face dental mirror and an explorer. 
 
➢ Intervention (Stela self-cured resin composite): 
1- Cavity Preparation: Both intervention and control restorations will be placed by 
the principal investigator in a single visit per participant. Local anaesthetic agent 
will be administered followed by rubber dam quadrant isolation and pre-wedging 
using wooden wedges of appropriate sizes. Cavities will be prepared using 330 
and 245 burs forming a trumpet-shaped outline; enamel margins will be bevelled, 
and proximal line angles will be finished using coarse and medium grit strips. Soft 
caries will be removed using sharp excavators of appropriate shapes and sizes. 
Finished cavities will be air-water rinsed to remove all blood and contaminants 
prior to bonding procedures. 
2. Bonding Procedures: Finished cavities will receive  pre-contoured metal sectional 
matrix bands of appropriate sizes. Suitable wedges and separator rings will be 
applied accordingly for all cavities. Then the cavity walls and margins will be 
primed using Stela primer and wait for 5 seconds before the next step. Cavity will 
be gently air-dried for 2-3 seconds.  
3. Composite resin packing: the composite will be placed as single increment and 
injected using capsule tip. 
4. Finishing and polishing: restorations will be contoured under copious coolant 
using medium grit diamond stones, then finished using fine-grit ones. Inter-
proximal surfaces will be finished using medium and fine-grit strips. Restorations 
will further be polished using diamond impregnated rubber points and cups and 
composite polishing paste. 
 
➢ Comparator (Beautifil II light-cured resin composite): 
1. Cavity Preparation: cavity preparation procedures will be carried out using 
appropriate rotary and hand instruments so that the final cavity will be caries free, 
with rounded internal line angles, saucer-shaped internal outline, and finished 
external enamel outline. No beveling of enamel margins will take place.  
2.  Bonding procedures: a sectional matrix system: thin pre-contoured metal matrix 
bands of appropriate sizes, suitable wedges and separator rings will be applied to 
all cavities. Selective etching approach will be followed whereas enamel will be 
etched for 30 seconds using 34-37% orthophosphoric acid, and then rinsed off with 
a steady shower of air-water for 15 seconds. Cavity will be gently air dried before 

15 
 
universal adhesive application and LED curing according to the manufacturer’s 
instructions.  
3. Cavity liner: a very thin layer of flowable composite resin will be applied over the 
bonded surfaces, gently agitated with an explorer to clear any bubbles, then LED 
cured according to the manufacturer’s instructions.  
4. Composite resin packing: composite will be packed in a centripetal pattern using 
non-sticky metal composite applicators of appropriate shapes and sizes; starting 
with a 1 mm vertical marginal ridge followed by oblique increments, sculpted to 
final anatomy, and not-more-than 2 mm thick each. Each increment will be cured 
according to composite resin manufacturer’s instructions using a LED dental lamp 
checked for intensity before each procedure.  
5. Finishing and polishing: restorations will be contoured under copious coolant 
using medium grit diamond stones, then finished using fine-grit ones. Inter-
proximal surfaces will be finished using medium and fine-grit strips. Restorations 
will further be polished using diamond impregnated rubber points and cups and 
composite polishing paste. 
9) Outcomes: 
Prioritization of 
Outcome 
Outcome  
Method 
of 
Measurement  
Unit 
of 
Measurement  
Primary  
Outcome 
Proximal 
contact 
tightness 
of 
examined 
restorations 
FDI criteria for 
direct and indirect 
restorations 
Number and 
% 
Secondary 
Outcome 
Postoperative 
hypersensitivity 
Visual Analogue 
scale 
 
Restorations will be given scores 1-5, where 1 is 'clinically excellent', and 5 is 'clinically 
poor'. Restorations receiving scores 1-3 are considered successful, while 4 and 5 are 
failed restorations requiring repair or replacement.  
One-week post-operative hypersensitivity will be examined using a visual analogue scale 
following the FDI criteria (absence/presence of hypersensitivity). 
 

16 
 
C) Data collection, management, and analysis: 
10.  Data collection methods 
10.a. i. Baseline data collection: 
For every patient, chief complaint, medical and dental history, and contact information 
will be recorded in examination charts and outpatient clinic software. Data entry will be 
done by the principal investigator S.W. 
10.a. ii. Outcome data collection: 
(A.G and M.F) will be calibrated to 100% agreement on 10 patients- not included in this 
trial. In cases of disagreement between evaluators, further discussion will take place till 
reaching consensus. 1ry and 2ry outcomes will be assessed following the FDI criteria and 
assessment tools. Evaluation will be done at baseline (T0) (1 week after restoration); (T1) 
at 6 months; (T2) at 12 months; (T3) at 18 months; and (T4) at 24 months. Post-operative 
hypersensitivity, however, will be assessed at 1 week (baseline) only followed by vitality 
assessment at following recall appointments.  
10. b. Patient retention:  
S.W. will record telephone numbers and addresses of all subjects in the study as a part 
of the signed consent. Patients will be contacted by phone one day before the follow-up 
dates. S.W will also explain to the patient the benefits of follow up and any defective 
restoration will be managed accordingly.  
 
11. Data management: 
S.W will electronically enter all the data. Patients’ files are to be stored in numerical 
order in a secured place. All paper sheets concerned with the personal or outcome data 
will be stored in a locked cabinet in the Conservative dentistry department, The British 
University in Egypt. The excel sheets of patients’ data will be stored in a computer in the 
Conservative Department, Faculty of Dentistry, the British University in Egypt. The 
computer will have a password only known to S.W. and A.G. to prevent unauthorized 
access to data and double data entry. A back-up will be made online to avoid data loss. 
 
D) Data monitoring: 
12. Monitoring  
The co-supervisor (A.G) will monitor this study for the risk of bias and to monitor 
blinding.  He will also have full access to the results and to take the final decision to 
terminate the trial when necessary.  
 
 
 

17 
 
13. Harms  
The principal investigator (S.W) will explain possible harms to patients. Zero harms are 
expected and if there are any adverse actions, the process will be stopped immediately 
and managed accordingly after reporting it to the co-supervisor (A.G) and main 
supervisor (M.F). 
14. Audit 
Auditing of the study design will be done by the main and co-supervisors to assure 
quality of the research procedures. 
 
Ethics and dissemination 
15. Research ethics approval 
This protocol will be reviewed, approved and agreed upon by the Ethics Committee 
(Research Ethics Committee, Faculty of Dentistry, The British University in Egypt) and 
an approval number will be provided to the trial protocol.  
 
16. Confidentiality 
Name and personal data of the participants will not appear on the protocol form and will 
be maintained secured for 10 years after the trial. This is done for protection of 
participants’ privacy and civil rights. 
 
17. Declaration of interest 
There is no conflict of interest, no funding or material supplying from any parties. 
 
18. Access to data 
The investigator and the co-supervisor will be given access to the data sets. All data sets 
will be password protected to ensure confidentiality. 
 
19. Post-trial care 
All patients will complete their treatment by the same operator at the outpatient clinic of 
the conservative department. Further dental complaints and follow-up after the trial ends 
will be conducted in the related internship clinic. 
 
20. Dissemination policy 
SW will publish the full protocol online in www.clinicaltrials.gov to avoid repetition and 
to keep the integrity of the research work. Thesis will be discussed in front of a judgment 
committee. SW will publish the study to report the results of this clinical trial. A copy of 

18 
 
the thesis will be available at the library of the Conservative dentistry department- The 
British University in Egypt; and the official website of the Egyptian Universities 
Libraries Consortium. Final report of the trial will be also published in an international 
journal. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

19 
 
VII. References 
 
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M. C., Popa, D. L., Popescu, A. D., & Țîrcă, T. (2023). Study on the restoration of Class II carious 
cavities by virtual methods: Simulation of Mechanical Behavior. Journal of Functional Biomaterials, 
14(7), 354.  
2. Ferracane, J. L. (2024). A historical perspective on dental composite restorative materials. Journal of 
Functional Biomaterials, 15(7), 173. https://doi.org/10.3390/jfb15070173 
3. AlShaafi, M. M. (2017). Factors affecting polymerization of resin-based composites: A literature 
review. The Saudi Dental Journal, 29(2), 48–58. https://doi.org/10.1016/j.sdentj.2017.01.002 
4. Warreth, A. (2023). Dental caries and its management. International Journal of Dentistry, 2023, 1–
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5. Toz-Akalin, T., Öztürk-Bozkurt, F., Kusdemir, M., Özsoy, A., Yüzbaşıoğlu, E., & Özcan, M. 
(2022b). Clinical evaluation of low-shrinkage bioactive material Giomer versus nanohybrid resin 
composite restorations: a two-year prospective controlled clinical trial. Operative Dentistry, 48(1), 
10–20. https://doi.org/10.2341/21-155-c 
6. Pallesen, U., & Van Dijken, J. W. (2015). A randomized controlled 30 years follow up of three 
conventional resin composites in Class II restorations. Dental Materials, 31(10), 1232–1244. 
https://doi.org/10.1016/j.dental.2015.08.146 
7. Pallesen, U., & Van Dijken, J. W. (2015b). A randomized controlled 27 years follow up of three resin 
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8. Jacob, G., & Goud, K. (2022). A comparative study on microleakage of two low shrinkage composite 
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9. Laporte, C., Bourgi, R., Jmal, H., Ammar, T. B., Hazko, S., Addiego, F., Sauro, S., Haïkel, Y., & 
Kharouf, N. (2025). Mechanical, Antibacterial, and Physico-Chemical properties of three different 
Polymer-Based direct restorative materials: an in vitro study. Polymers, 17(9), 1272. 
https://doi.org/10.3390/polym17091272 
10. Raghip, A. G. M., Comisi, J. C., Hamama, H. H., & Mahmoud, S. H. (2025). Two-Year Randomized 
Clinical Trial to Evaluate the Performance of Posterior Bulk-Fill Resin Composite with Ionic 
Releasing 
Restorative 
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11. Pires, P. M., Neves, A. A., Farrar, P., Cascales, Á. F., Banerjee, A., Feitosa, V. P., & Sauro, S. (2025). 
Bonding Performance and interfacial Ultra-Morphology/Nanoleakage of a modern Self-Curing Bulk-
Fill restorative System: an in vitro study. European Journal of Dentistry. https://doi.org/10.1055/s-
0045-1804886 
12. Guarneri, J. a. G., Maucoski, C., Ghaffari, S., MacNeil, B. D., Price, R. B., & Arrais, C. a. G. (2024). 
Ability of a novel primer to enhance the polymerization of a self-cured resin composite. Dental 
Materials. https://doi.org/10.1016/j.dental.2024.10.013 
13. Loguercio, A. D., Carpio-Salvatierra, B., Ñaupari-Villasante, R., Wendlinger, M., Armas-Vega, A., 
Cavagnaro, S., León, A., Aliaga-Galvez, R., & Gutiérrez, M. F. (2024b). Clinical evaluation of a new 
Chemically-Cured Bulk-Fill composite in posterior restorations: 6-Month multicenter Double-Blind 
randomized 
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https://doi.org/10.1016/j.jdent.2024.105246 

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14. Loguercio, A. D., Carpio-Salvatierra, B., Ñaupari-Villasante, R., Armas-Vega, A., Cavagnaro, S., 
León, A., R, A., Soares, C. J., & Gutierrez, M. F. (2025). Clinical evaluation of a new Chemically-
Cured Bulk-Fill composite in posterior restorations: 18-Month multicenter Double-Blind randomized 
clinical trial. Journal of Dentistry, 162, 106031. https://doi.org/10.1016/j.jdent.2025.106031 
15. De Carvalho, L. F., Silva, M. G. E., Da Silva Barboza, A., Badaró, M. M., Stolf, S. C., Cuevas-Suárez, 
C. E., Lund, R. G., & De Andrade, J. S. R. (2024). Effectiveness of bioactive resin materials in 
preventing secondary caries and retention loss in direct posterior restorations: A systematic review 
and meta-analysis. Journal of Dentistry, 152, 105460. https://doi.org/10.1016/j.jdent.2024.105460