The term “caries excavation” is defined as mechanical treatment of dental caries-induced tooth damage to best fit the remaining parts of the tooth to receive a filling.^[1] Ogushi and Fusayama have demonstrated the two zones within a carious lesion. An inner layer of intact collagen (affected dentin) and a second zone with partially destroyed collagen fibrils that cannot be remineralized (infected dentin).^[2] Dental researchers worldwide though are very interested in the concept of retaining sound dentine.

Caries excavation with the use of air-rotor is frequently associated with patients’ discomfort and pain, which subsequently necessitates the administration of local anesthesia.^[3] Alternative techniques such as lasers, ultrasonic instrumentation, and air abrasion have been developed for caries removal to decrease the pulpal responses, but they are less often used by the pediatric dentists due to economic concerns of some of these techniques.^[4]

Chemomechanical caries removal (CMCR) is a noninvasive procedure that protects healthy tooth structures while eradicating infected tissues without causing pulp irritation or discomfort to the patient.^[5] Chemomechanically treated dentin has more surface energy, a stronger affinity for adhesive material, and better bonding than untreated dentin.

Carisolv, the most recent variant of the NaOCl-based chemomechanical agents, was launched in 1998.^[6] The gel softens the carious dentine while leaving the healthy tissue unharmed.^[7] Because deteriorated collagen has an open structure, it is more susceptible to Carisolv penetration, and this dentin can be simply scraped off with improved Carisolv instruments.^[8] The downsides of adopting Carisolv include the substantial training and registration of specialists that is necessary, as well as the need for customized devices, which raises the solution’s cost.

Papacarie was made available as a proteolytic gel in 2003.^[9] The latex of the Carica papaya is used to make papain. The new medicine contains the collagen degradation features of papain as well as bactericide characteristics of chloramines. By interacting with the exposed collagen and softening the carious dentine, papain dissolves the decaying tissues enabling the removal of the carious dentine without the necessity for drilling or local anesthesia.^[10,11] As per Dawkins et al., both Gram-positive and Gram-negative organisms replication can be hampered by papain application. With the Papacarie technique of caries removal, dental professionals can remove all of the carious dentine while protecting the unaffected dentine without the use of a special instrument. Papain’s enzymatic action is thought to be beneficial in areas with necrotic and purulent tissues.^[2,12-15]

There is also a significant lack of systematic research regarding the effectiveness of Papacarie and Carisolv in primary teeth in terms of antibacterial activity. Primary dentition is more prone to lesion progression and development. In addition, there are very few outcome factors in earlier systematic reviews. Therefore, in an effort to compare the effectiveness of Papacarie and Carisolv in primary teeth, we carried out a systematic review.

The purpose of this systematic review is to assess the methodology used in earlier published medical studies on Papacarie and Carisolv, as well as to investigate the difference in pain perception, time required, and microbiological analysis before and after caries removal in primary teeth.^[16,17]

CMCR involves chemically softening carious dentine and then gently excavating it. It has gained importance due to its property of selective removal of carious lesion with avoidance of pain.^[8] One of the justifications for the specialty of pediatric dentistry is the instillation of a good attitude toward oral health care as well as comfort, peace, and alleviation. The patients’ dental health for the rest of their lives may be impacted by a mild and painless treatment experience.^[27-30] A mild and comfortable treatment experience may have a long-term impact on the patients’ oral health.

Ansari et al. favored the CMCR method over the conventional method because it is less distressing, requires less local anesthesia, has a high patient preference, has a lower probability of exposure in deep carious cavities, is helpful in immunocompromised patients and patients with bleeding disorders, and has better bonding to restorative materials.^[22,31,32] Papacarie is a CMCR procedure that consists of papain, chloramine, toluidine blue, deionized water, preservatives, stabilizers, and salts that aid in the removal of damaged tissues. Infectious tissues lack anti-trypsin, a plasmatic anti protease found only within healthy dentine which is responsible for preventing tooth structure destruction. Flindt showed that papain’s action was restricted in these bacterial tissues.^[11,23] After the first application of Papacarie gel for 30–60 s, dental caries is excavated using hand instruments. The procedure is repeated until the lesion surface feels firm and the gel is clear. The cavity is then sprayed with water and cleaned with a cotton pellet. Papacarie works by dissolving the collagen molecules that have partially disintegrated. Collagen fibril crosslinks are hydrolyzed by it. During the clinical procedure, the development of bubbles on the surface and blearing of the gel show that the degradation is happening and oxygen is being released, proving that the elimination process has started.^[24]

Carisolv is a NaOCl-based CMCR product that is commercially marketed. The three amino acids, namely glutamic acid, leucine, and lysine are differently charged. Each of Carisolv’s three chloro-amino acids electrotatically attracts one of the hydrophilic and hydrophobic patches present in protein peptide chains such as collagen.^[4] It promotes reactive power along the entire length of the collagen fiber while decreasing the unfavorable adverse effects of hypochlorite. The chemical outcome of these activities is collagen breakdown, which is common in the demineralized section of a carious lesion. This softened dentine with deteriorated collagen can be easily scrapped off with Carisolv instruments.^[5] Consequently, the goal of this systematic review was to compare the Papacarie technique of caries removal to the Carisolv strategy in terms of pain perception in a clinical setting, time taken, and microbiological assessment before and after carious removal in primary teeth.

Various scales have been used to capture patients’ feelings following caries eradication, as pain perception is a subjective measure. Wong-Baker Faces Pain Rating Scale (WBFPS) is more sensitive as compared to other pain assessment scales. The WBFPS depicts six faces. Kids are asked to choose the expression that best represents their own personal suffering. Faces 0 and 2 do not hurt at all, whereas Faces 4 and 6 do hurt somewhat more, Face 8 significantly more, and Faces 10 as severely as you can conceive. Kochhar et al. used Visual Analogue Scale as well as VPS, Hegde et al. used WBF and Moimaz et al. used a mere questionnaire for recording pain perception.^[18-20] Pain perception was almost similar for both Papacarie and Carisolv in all the three trials with Papacarie technique proving to be less painful as compared to Carisolv. Pain associated with Carisolv might probably be because of the prolonged time taken to remove the caries. Bohari et al. used FLACC scale and found Carisolv to be less painful.^[26] Subjective nature of pain as well as variability of the pain threshold among individuals may be responsible for difference in results. The CMCR agents cover the entire cavity during treatment; they may serve as a heat insulator. In addition, the technique anticipates opening less dentinal tubules than drilling. Chemomechanical techniques, which are almost painless, are effective for treating special health care needs children because any stimulation, whether aural, sensory, or emotional, might cause adverse reactions.^[27] Individuals’ terror of the dentist increased in the CMCR group while it decreased marginally in the normal rotary procedure, according to Inglehart et al. This finding has been attributed to the CMCR technique’s lengthy treatment time.^[28]

In the present systematic review, treatment time was chosen as outcome to evaluate the efficiency of Papacarie and Carisolv in caries removal. Kochhar et al., Bohari et al., Chowdhry et al., Hegde et al., and Moimaz et al. made a conclusion that Carisolv method is more time consuming than Papacarie.^[17-20,26] However, because there is no agreed-upon standard for measuring treatment duration, the variability of treatment time is substantial. Time was registered with a stopwatch by Chowdhry et al., Hegde et al., and Moimaz et al.^[17-19] Less time was required for Papacarie as compared to Carisolv as fewer number of applications are required with the Papacarie method. The use of customized Carisolv hand instruments all the more increases the treatment time.^[29] Papacarie’s work time acceptance in pediatric dentistry was demonstrated by Carrillo et al. in 2008 as 4–8 min.^[27]

Bacteriological investigation was selected as a means of evaluation to determine the efficacy of both procedures (Papacarie and Carisolv) for caries eradication. El-Tekeya et al., Ammari et al., and Moimaz et al. examined antibacterial efficiency by giving particular results of CFU decrease.^[16,19,21] Papacarie could significantly reduce the colony-forming units of both S. mutans and Lactobacillus as compared to Carisolv.^[30] A proteolytic enzyme called papain possesses anti-inflammatory, antibacterial, and bacteriostatic properties. The chloramine chlorinates the deteriorated dentine collagen, which is then simple to remove using an excavator. Toluidine blue is a photosensitive pigment present in Papacarie that binds to the bacterial membrane and has been discovered to be quite efficient against S. mutans.^[24]

Two studies in the present systematic review showed risk of bias due to problems in random sequence generation, allocation concealment, and blinding of outcome assessment. The study of Kochhar et al. showed moderate risk of bias as the outcome assessors were aware of the interventions received by the study participants. The study of Bohari et al.^[20,26] showed high risk of bias as there was some concern arising from the randomization process as the allocation sequence was not randomized. There was also moderate risk arising due to deviation from intended intervention in this study. However, the remaining five studies demonstrated low risk of bias which improved the quality of the review.

Papacarie reduced pain perception during caries excavation in primary teeth and had a quicker treatment time.^[34,35] Papacarie is also far more effective than Carisolv at reducing cariogenic bacteria in the dentin of primary teeth as assessed by the included studies with low risk of bias.