1. Introduction

Pain has accompanied humans since their appearance on earth. Different natural remedies with analgesic properties date back to ancient Egypt and Greeks, including Dioscorides and Hippocrates who prescribed the use of willow bark with salicylic acid as the main ingredient. In the late nineteenth century, three prototypes of today's modern nonopioid

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antipyretic analgesics were discovered: acetaminophen and aspirin (formulated in 1895 by Frederick Bayer and Felix Hoffman) and phenazon, which still make up about 50% of the market of antipyretic analgesics worldwide [1]. Opiates such as morphine, which are derived from the opium poppy, were also used for thousands of years. Later on codeine, as a naturally methylated morphine, was isolated in France in 1830 by Jean-Pierre Robiquet. In 1937, German scientists Max Bockmuhl and Gustav Ehrhart synthesized methadone [2].

Pain is a subjective symptom signaling a requirement to act urgently and is usually associated with other subjective feelings such as anxiety, anger and discomfort. The expression of nature and intensity of pain is a subject of different patient-related characteristics. There are several patient factors having an impact in the patient's interpretation of pain, such as gender, age, physiological factors and drug abuse history, neuropathic and other disease and psychological profile of individual humans [3].

Dental pain (toothache or odontalgia) is a common subjective complaint of dental patients following the different interventional procedures and dental diseases. Dental pain presents one of the most common causes (approximately 12%) of patients seeking emergency treatment in dental healthcare in the United States [4].

Odontogenic pain is a complex cascade process initiated from dental tissue damage and accompanied with heterogeneous neuronal stimuli as a consequence of neurovascular, neuroinflammation and morphologic reactions [5].

The development of new analgesics is a very dynamic process and nowadays clinicians have a greater range of agents in order to select the most efficient and safe analgesic therapy. Taking into consideration the period 1960–2009, 59 analgesics have been introduced and their use still remains important [6].

Analgesics are considered one of the most important drugs groups in dental practice considering the prescription rate, clinical efficacy, cost-effectiveness and safety profile of this drug group. According to this level of importance in dental clinical practice, there are different approaches to develop treatment algorithm and guidelines for dental pain treatment in order to rationalize the use of analgesics. The rationalization of analgesics use is an ongoing challenge, since some analgesics are over-the-counter (OTC) drugs and can be taken without medical prescription.

The management of dental pain in clinical practice is a complex part of dental care and requires high-level knowledge of analgesic pharmacology and implementing the standards of rational use.

There is a valuable evidence for significant relationship between nonrational use of analgesics and diminution of drug therapy, increased adverse drug reactions and socioeconomic consequences [7, 8].

Nevertheless, prescription of analgesic drugs for dental indications is often accompanied with challenges, which diminish the treatment success and increase the potential risk for serious adverse effects.

There are several reasons for the decrease in clinical efficacy of analgesic therapy, including the lack of real assessment and monitoring of pain by dentistry doctor, nonadequate quantification of subjective pain experienced by patients, lack of updated pharmacological knowledge of dental pain treatments, experience scarcity in safety profile of analgesic and insufficient knowledge regarding analgesic combinations. There is evidence that prescription errors with analgesic medicaments are substantially high and are a major cause of manifestations of analgesics side effects [9]. The percentage of analgesic-related prescription errors, as reported by Smith et al., is relatively high, with 29% in adult patients and in pediatric patients it is even higher at 59%. From total prescription percentage, 14% were serious or severe analgesic prescription errors with high harmful potential for patients, mainly in pediatric patients [10].

The prescription of analgesic drugs and treatment of dental pain is more complex when it is accompanied with other health disorders and diseases. In these cases, quantification of pain and its evaluation and treatment is a convoluted clinical challenge. The main complex challenges are patients with diabetes and other chronic diseases, patients with renal and hepatic insufficiency and patients with opioid addictive disorders [11, 12].

Pain has an impact in the quality of life of patients with complaints for prolonged experience of pain, it increases healthcare costs and it is a risk for progress to chronic pain with negative reflection in health and mental status of patients [13]. The experience of prolonged pain brings healthcare workers under more complex situations and the selection of appropriate pain treatment is more difficult [14].

Rational prescription of analgesics in dentistry involves the selection of appropriate pain reliever, right clinical indication, selection of adequate dosage and route of administration and implementation of cost-effectiveness and risk-benefits standards.

Hence, information with the objective of elaborating an analgesic's utilization patterns is considered as of high relevance in order to optimize the pain treatment in dentistry.
