Retaining primary molars is of prime requisite for mastication, preserving arch length, growth of jaws, and also protect from developing oral habits. Hence, essential pulp treatment focus to treat reversible pulpal injuries, in which tooth is affected by caries, injury, or any restorative procedures. Pulpotomy is as yet comprehensively performed treatment for cariously involved pulp in asymptomatic primary molars. ¹

Pulpotomy materials are classified according to devitalization, preservation, and regeneration. Formocresol a devitalizing agent used for pulpotomy was introduced by Sweet in 1932. It was a successful material with some disadvantage. There has been the plenty of literature about the suitability and well-being of utilizing this aldehyde-based material in pediatric dentistry. ²

Since the introduction of mineral trioxide aggregate (MTA), there has been a keen interest in regenerative endodontics. ³ Newer regenerative materials with bioinductive, biocompatible, and bactericidal properties have been launched. These preserve the healthy radicular pulp tissue.

Although MTA has been used extensively, the material has some inherent limitations that include high solubility, difficult handling characteristics, presence of toxic elements in the composition, higher cytotoxicity in its freshly mixed state (ISO 10993-5) (ISO 10993-3), ⁴ , ⁵ and high pH during setting. This inflicted to the evolution of newer improved MTA-based products (such as MTA Plus, Retro MTA, ortho MTA, Endocem MTA, MTA Fillapex, Endoseal.) MTA Plus (MTA Plus™ ⁾(Prevest Denpro Limited, Jammu, India; lot. 41001 Avalon Biomed Inc.) was introduced with a finer particle size to improve the handling characteristics of MTA. A new bioceramic material, Retro MTA ^®(BioMTA, Seoul, Korea) was also introduced to upgrade the properties of MTA. RetroMTA contains zirconia, a radiopacifying agent, which does not cause discoloration and is fast setting. ⁶

Biodentine™ (Septodont, Saint-Maur-des-Fosses, France) is a tricalcium silicate (Ca3SiO5) based inorganic restorative cement and is used as an alternative to MTA. ⁷ It is also known as “bioactive dentine substitute” and has higher mechanical properties. ⁸ BD™ has an advantage over MTA, besides its biocompatibility, mechanical, and physical properties are better.

Calcium enriched mixture (CEM) cement (Bionique Dent, Tehran, Iran) is a calcium silicate-based material. ⁹ The sealing ability of CEM is comparable to MTA. ¹⁰ With its smaller particle size, CEM can promote hydroxyapatite and also induce hard-tissue formation. ¹¹ It also shows a superior antibacterial effect and improved handling. ⁹ Several studies have compared MTA with other materials for pulpotomy in primary teeth. ¹² , ¹³ , ¹⁴ , ¹⁵ Most studies on pulpotomy compared regenerative materials with devitalizing and preservative materials. ¹⁶ , ¹⁷

Hence, the aim was to evaluate the clinical and radiographic success of MTA-based materials (MTA Plus™ and RetroMTA ^®) and compare with BD™ and CEM cement as pulpotomy medicament in deciduous molars.

In this interventional study design, normal, healthy, and cooperative children were selected from the patients attending the Department of Pedodontics and Preventive Dentistry, The Oxford Dental College, Bengaluru, India. Permission was obtained from institutional ethical review board (222/2014-15, 430/2015-16). The dental health of the child and treatment required was discussed with the parents of the children. Prior written consent was obtained from the parents for carrying out the pulpotomy procedure, and the importance of periodic follow-up visits was explained.

One hundred and twenty teeth were chosen in 30 children aged 3–9 years, who had no medical condition that would contraindicate pulp therapy. As it an open-label trial, the participants were aware of regenerative materials placed in their teeth. Four primary molars were involved in the study, thus each participant had to have at least four primary molars (first and/or second mandibular and maxillary primary molars), requiring pulpotomy. A brief history was recorded, and the teeth were exposed to the clinical examination and radiographic evaluation before the beginning of the study.

Vital primary molars with probable carious pulp exposure, absence of spontaneous pain or persistent pain, no clinical symptoms or evidence of pulp degeneration such as pain on percussion, history of swelling or sinus tracts, hemorrhage from the amputation site is bright red and easy to control and teeth that could be restored with stainless steel crowns. ¹⁸ , ¹⁹

Radiographic criteria: No evidence of physiologic root resorption, absence of furcal and/or periapical radiolucency, absence of internal or external root resorption, absence of pathologic root resorption. ¹⁸ , ¹⁹ In this split-mouth study design (complex randomization), four primary molars were allocated by the lottery method to four groups in each participant. The teeth requiring pulpotomy were selected based on the above-mentioned criteria. Once the child is made to sit on the dental chair for the treatment, according to lottery method, the chits of materials name written on it were placed in the box and children were allowed to pick the chits. Thus, the child had to pick four chits one after other so that all the materials are selected once. The selected materials were randomly placed onto the tooth.

Group I: BD™ (Septodont, Saint-Maur-des-Fosses, France)

A conventional pulpotomy procedure was performed on the selected teeth. Following the administration of local anesthesia (LOX 2% adrenaline 1:200,000, 30 ml, NEON laboratories limited, Mumbai, India) rubber dam (GDC rubber dam kit, GDC Fine Crafted Dental Pvt Ltd.) isolation was carried out. All dental caries and overhanging enamel were removed with a No. 330 FG high-speed small diamond bur (0.9 mm Diameter, 2.8 mm Length, Midwest® Dentsply Sirona) with water spray. Removal of all carious dentin was carried out. A sterile No. 4 RA (diameter 1.4 mm, length 1.4 mm DENTSPLY) or 8 RA (diameter 2.3 mm, length 2.3 mm DENTSPLY) round slow-speed diamond bur was used to remove entire coronal pulp. The pulp stumps were excised until the canal orifices seen clearly with no tags remaining on the pulpal floor. Irrigation of the pulp chamber was done using normal saline. After completion of the amputation, hemorrhage was controlled within 3–5 min using slightly moistened cotton pellets placed against the pulp stumps at the orifices of the root canals. ¹⁸ , ¹⁹

In group I, BD™ (Septodont, Saint-Maur-des-Fosses, France) five drops of liquid from the pipette were added to the capsule containing 0.7 g of powder, as per the manufacturer's instruction. The content of the capsule was then triturated for 30 s at 4200 rpm. A plastic carrier (provided by the manufacturer) was used to transfer the mix, to standardize the quantity of material placed. The material was condensed over the root canal orifices using an amalgam carrier and moistened cotton pellet. The pulp cavity was filled with BD™. The material was condensed lightly using a cylindrical amalgam condenser to confine the placement of the material at the root canal orifices. ²⁰

In Group II, MTA Plus ^™(MTA P) (MTA Plus (Prevest Denpro, Avalon Biomed Inc, Jammu, India; lot. 41,001) 1 scoop of powder was dispensed on a glass slab and 1 drop of the liquid anti-washout gel was added to the powder and mixed on a glass slab with a cement spatula. The powder/gel ratio was 2.5:1 by weight. The thick mix of MTA Plus™ was then placed at the root canal orifices using a plastic filling instrument and condensed lightly using an amalgam cylindrical condenser. ²¹

In Group III, RetroMTA ^®(R-MTA) (BioMTA, Seoul, Korea) the cap was opened and 0.3 g of powder from the pouch was dispensed into the floor of the cap. The plastic pipette was cut with scissors and three drops of liquid (distilled water) were added onto it. An agate spatula was used for wetting the powder with liquid for 20 s. To standardize the quantity of the material used, an MTA carrier was used to transfer the RetroMTA ^®to the root canal orifices. The material was condensed with proper pressure using a cylindrical condenser to confine the material placement at the root canal orifices. ²²

In Group IV, CEM cement (CEM cement ^®, BioniqueDent, Tehran, Iran) powder and the liquid were dispensed onto a mixing pad at a ratio of 1:1 by weight according to manufacturer's instructions. Gradually, the liquid was incorporated into the powder using plastic spatula for 15–30 s to ensure that all powder particles were hydrated. More liquid was added to achieve a thick and creamy consistency. A wet gauze pad was used to cover the mixed material to prevent evaporation, hence increasing the working time. The CEM cement was carried to the root canal orifices using a plastic filling instrument and adapted to the orifices with dry cotton pellets using gentle pressure. ⁹

In all the teeth, following placement of the regenerative agents, the pulp chamber was filled with GC Miracle Mix ^®(GC Corporation, Tokyo, Japan) following rubber dam removal, the occlusion was checked for high points using articulating paper. Final restoration with a stainless-steel crown (3M ESPE, Dental Products, St. Paul, MN, USA) was given following the pulpotomy procedure. ²³

The patients were recalled for clinical and radiographic evaluation at 6, 12, 18, and 24 months. Clinical evaluation was done by noticing any signs and symptoms in the tooth treated. Radiographically, an intraoral periapical radiograph was taken for the evaluation. Radiographically, X-rays were evaluated under the X-ray viewer by three examiners and findings were noted separately for each child and each material. The examiners were aware of the materials placed. Participants were also instructed to report to the department on the development of any signs and symptoms regarding the treated teeth, during the intervening period. At the end of 2 years follow-up, 27 children were available, as 2 children relocated to other states and one child's parents did not give consent for continuing the study at 2 months period.

Statistical analysis

Data obtained were subjected to the statistical analysis using SPSS (Statistical Package for the Social Sciences) for Windows version 22.0 Released 2013. Armonk, NY, USA: IBM Corp. The Chi-square Test was used to compare the clinical and radiological parameters between different study groups at 18 months and 24 months of follow-up periods. The level of significance was set at P < 0.05.

At the end of the study period, 27 children and 108 teeth were available Table 1and Table 2. Clinically and radiographically, all teeth were rated successful until the 12-months follow-up period. In the 18 ^thmonth, clinically one failure was seen with Group II Table 3. In the 24 ^thmonth, one more failure was seen with Group III (P = 0.86) Table 4with the Chi-square value χ ²= 0.750. At 18 ^thmonth, radiographically, one failure was observed in Group I and Group II groups, whereas no failure was observed in Group III and Group IV Table 5with Chi-square values χ ^2:10.500, P = 0.31. At the 24-month follow-up, one radiographic failure was observed in Group I and Group IV; two failures were observed in Group III Table 6with Chi-square values χ ^2:10.500, P = 0.31. The percentage of radiographic failures and clinical failure showed were 92.5% in Group I and Group II, 88.8% in Group III, and 96.5% in Group IV at the end of the study thus there was no statistically significant difference seen between the groups (P = 0.05) Table 7.{Table 1}{Table 2}{Table 3}{Table 4}{Table 5}{Table 6}{Table 7}

A short procedural period is critical to reduce the likelihood of disruptive behavior among pediatric patients. Nowadays, newer materials which are biologically acceptable are considered superior in dentistry, as the priority has changed from preservation to regeneration. Hence, materials with better biologic properties such as improved antibacterial activity, ability to form odontoblast like cells, less cytotoxic activities and few mechanical properties like improved radiopacity, no microleakage, fracture resistant, increased shear bond strength and faster setting time has been introduced. These properties of the materials help enhance the success rate of the treatment done in primary teeth. In present study, regenerative materials like BD ^™MTA-based cements (MTA Plus ^™, Retro MTA ^®) and CEM cement ^®were assessed clinically and radiographically in pulpotomy procedure. These materials have got improved biological and mechanical properties. ²⁰ , ²¹ , ²² , ²³

Pulpotomy was regarded as successful with no clinical signs and radiographic failures. The pulp in primary teeth is more cellular and has a greater blood supply which can play an important role in the success rate of pulpotomy.

In the present study, Group I (BD™) showed the clinical success of 100% during the overall study period. The absence of clinical signs and symptoms may be due to the inherent property of BD™ itself. The setting and hardening of the cement happened because of the ability of calcium silicate that has interacted with water. Tricalcium silicate mixed with the liquid component leads to the formation of a hydrated calcium silicate gel and calcium hydroxide. BD™ forms hydroxyapatite crystals at the surface. The sealing ability at the interface of the material and dentinal walls increased by these crystals. BD™ is mechanically stronger, less soluble with increased compressive strength, decreased porosity which gives a tighter seal. ²⁴ , ²⁵

BD™ also inhibits the growth of streptococcus mutans and Enterococcus faecalis. Thus, the antibacterial property of BD™ is proved to be better as compared to MTA. ²⁶ This property is very significant for the clinical success of any restorations. The above-mentioned properties of BD™ could also be one of the contributing factors for the clinical success observed throughout the evaluation period. El Meligy et al. reported 100% success rate with BD clinically and radiographically in primary molars in a 12 months randomized controlled trial. ²⁷

Radiographically, at 18 months of evaluation period in Group I, External root resorption Figure 1one primary molar which was considered as a failure. The reason for this can be individual immunological response to the regenerative agent. Gonçalves et al. ²⁸ reported that the teeth treated with pulpotomy procedure were approximately three times more likely to have a periapical lesion, a finding which follow with that reported by Aminabadi et al., ²⁹ who reported that root resorption was the second most common finding with the teeth undergone with pulpotomy procedure. Thus, root resorption can be due to errors in the diagnosis or due to failures in the performing the pulpotomy procedures. Nasseh et al. reported that BD™ showed highest clinical and radiographic success with the primary molars with root resorption. Thus, the study concluded that BD™ is better material as pulpotomy agent. ³⁰ Figure 1

Internal root resorption and external root resorption seen with biodenitne and mineral trioxide aggregate plus.

All the four regenerative materials can be successfully used as pulpotomy agents in primary teeth.

Financial support and sponsorship

Nil.

Conflicts of interest

The authors of this manuscript declare that they have no conflicts of interest, real or perceived, financial or nonfinancial in this article.