Introduction Heat is generated and transferred to the dentine-pulp complex during various dental procedures, such as from friction during cavity preparations, exothermic reactions during the polymerisation of restorative materials and when polishing restorations. For in vitro studies, detrimental effects are possible when intra-pulpal temperature increases by more than 5.5°C (that is, the intra-pulpal temperature exceeds 42.4°C). This excessive heat transfer results in inflammation and necrosis of the pulp. Despite numerous studies stating the importance of heat transfer and control during dental procedures, there are limited studies that have quantified the significance. Past studies incorporated an experimental setup where a thermocouple is placed inside the pulp of an extracted human tooth and connected to an electronic digital thermometer. Methods This review identified the opportunity for future research and develop both the understanding of various influencing factors on heat generation and the different sensor systems to measure the intrapulpal temperature. Conclusion Various steps of dental restorative procedures have the potential to generate considerable amounts of heat which can permanently damage the pulp, leading to pulp necrosis, discoloration of the tooth and eventually tooth loss. Thus, measures should be undertaken to limit pulp irritation and injury during procedures. This review highlighted the gap for future research and a need for an experimental setup which can simulate pulp blood flow, temperature, intraoral temperature and intraoral humidity to accurately simulate the intraoral conditions and record temperature changes during various dental procedures.

Visual impairment is a global problem that remains unaddressed. Globally, it is estimated that 253 million people live with visual impairment, of which 1.4 million are children with complete blindness. 1 The WHO has several initiatives to promote a world without avoidable visual impairment, and where people with unavoidable vision loss can still achieve their full potential. 2,3 Vitamin A deficiency is the leading cause of blindness in developing countries, followed by infectious diseases. 4 In highly developed countries, prematurity complications are the most common cause of blindness. 4 As more premature children survive with visual impairments; there is an increasing need for appropriate services to protect this population. 5

The study investigated the cooling efficiency of different numbers of water coolant ports on high-speed handpieces (HSH) under cooling conditions used in clinical practice. Twenty-four groove cuts with water on and nine cuts without water were made on extracted human premolars using three HSHs with different port configurations. Thermocouples were placed in the pulp chambers and temperature changes were recorded with 1-, 3- and 4-coolant port handpieces. Cooling rate was calculated for each coolant port design system. Temperature changes were statistically analysed with Kruskal-Willis Test. All three sample groups resulted in a net temperature decrease during the cutting period with water turned on. There was a pattern of increased cooling rate with increasing number of coolant ports (1-port: -4.27 (±0.94) °C, 3-port: -4.66 (±2.90) °C, 4-port: -5.03 (±1.08) °C). The difference was not statistically significant ( p = 0.681). Calculations of cooling rate showed a higher cooling rate with an increase in the number of ports (1-port: 46.13 × 10 −4 K −1 , 3-port: 51.36 × 10 −4 K −1 , 4-port: 56.32 × 10 −4 K −1 ). In the dry tooth preparation samples, all resulted in a net increase in temperature (1-port: 4.43 (±3.30) °C, 3-port: 5.13 (±3.27) °C, 4-port: 2.87 (±2.97) °C). All the three water coolant port configurations showed effective cooling of the tooth during cutting and decreased pulpal temperature with no statistical difference. There are HSH designs with varying numbers of coolant ports available in the market for clinicians. The results of the current study could potentially aid clinicians in making a decision while choosing between different dental handpieces.

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The aim of this paper is to systematically review the literature to determine whether early childhood caries (ECC) is significantly associated with caries development in permanent teeth among school children and adolescents, and to identify the association of other risk factors over 24 months. A systematic literature search was performed in four electronic databases and via a manual search from inception to 28 July 2022. Independent study selection and screening, data extraction, evaluation of risk of bias using ROBINS-I tool and certainty of evidence with GRADE were performed. Ten cohort studies were included, all of which identified that ECC significantly increased the risk of caries in permanent teeth. Meta-analysis suggested children with ECC were three times more likely to develop caries in their permanent teeth (OR, 3.22; 95% CI 2.80, 3.71; p < 0.001), especially when the lesions were in primary molars and progressed to dentine. However, the certainty of evidence was substantially compromised by serious risk of bias and inconsistency between studies. There were inconsistent findings between socioeconomic or behavioural factors on caries development, which could not be pooled for meta-analyses. ECC significantly increases the likelihood of caries development in permanent teeth. Evidence on the association of socioeconomic and oral health behavioural factors is weak.