Minimally Invasive Chemomechanical Caries Removal in Paediatric Dentistry: A Systematic Review of Papacarie and Brix 3000

Background/Objectives: Dental caries is one of the most prevalent chronic diseases in childhood. Rotary bur handpiece excavation has been the standardised mechanical benchmark for infected dentine removal in the primary dentition, but it is associated with noise, vibration, and nociceptive triggers that influence behavioural cooperation in paediatric patients. CMCR gels have been developed for selective softening and excavation of infected primary dentine without macroscopic removal of adjacent sound tissue at the protocol-defined site. The objective of this review was to systematically synthesise the evidence on chemomechanical caries removal (CMCR) using Papacarie or Brix 3000 compared with infected dentine excavation using rotary bur handpiece instrumentation in the primary (deciduous) dentition, focusing on excavation effectiveness, paediatric procedural tolerance, anaesthetic requirement, dentine surface morphology at the excavation interface, and protocol-level operative duration per primary molar. Methods: A systematic search was performed in PubMed, Web of Science, and Scopus for English-language studies from database inception to 31 December 2023. Although no eligible paediatric dental records addressing CMCR gels for excavation of infected primary dentine were identified before 2009, the earlier literature was not intentionally excluded; rather, it did not retrieve topic-specific matches meeting the eligibility criteria. Clinical and in vitro investigations evaluating CMCR gels (Papacarie or Brix 3000) for excavation of infected primary dentine in primary molars were eligible. Outcomes were aggregated qualitatively by excavation approach and reported per primary molar at the individual study protocol level. Quantitative pooling or meta-analysis was not conducted due to heterogeneity in study designs and lack of unified denominators across the included literature. Results: Fifteen studies were included (randomised clinical trials, observational clinical investigations, clinical comparative studies, and in vitro assessments) evaluating infected dentine excavation in primary molars. CMCR gels achieved successful excavation of infected primary dentine with dentine preservation at the adjacent non-infected interface without macroscopic loss of sound tissue. Individual study protocols that reported paediatric pain outcomes during primary-molar excavation registered lower pain scores, reduced acoustic/vibratory stress, lower anaesthetic escalation cycles, and decreased local anaesthesia requirement per primary molar compared with rotary bur handpiece excavation arms. Dentine surfaces analysed under SEM protocols at the infected excavation interface described patent tubules, absence of compacted smear at the interface, preserved intertubular dentine, and no iatrogenic gouging or macrofracture of non-infected primary dentine per molar at the individual study level. Operative duration for CMCR ranged from 10 to 25 min per primary molar per tooth, while rotary bur handpiece excavation required 3–10 min per primary molar per tooth, depending on cavity extension and dentine hardness, as defined by each study protocol. Microleakage and bond-strength assays performed in vitro at the individual protocol level did not register disadvantage signals traceable to adhesive or sealing incompatibility following CMCR gel excavation per primary molar. Conclusions: CMCR with Papacarie or Brix 3000 enables protocol-level selective excavation of infected primary dentine in primary molars, reducing acoustic, vibratory, and nociceptive triggers that influence behaviour and local anaesthetic requirement per primary molar. Clinical inference should be restricted to infected dentine excavation per primary-molar denominators, avoiding extrapolation to all caries depths or all deciduous-tooth types. Standardised paediatric primary-molar infected dentine excavation trials with homogeneous denominators, bias-controlled outcome instruments, and longitudinal follow-up are required to strengthen cavity-depth indications, pulp-proximal excavation reliability, and restorative longevity guidance in the primary dentition clinical workflow.