A Model for Opioid Risk Stratification: Assessing the Psychosocial Components of Orofacial Pain

Limonene, a citrus monoterpene, non-complexed and complexed with hydroxypropyl-β-cyclodextrin attenuates acute and chronic orofacial nociception in rodents: Evidence for involvement of the PKA and PKC pathway

BACKGROUND

Chronic orofacial pain is a serious public health problem with a prevalence of 7-11% in the population. This disorder has different etiologies and characteristics that make pharmacological treatment difficult. Natural products have been shown to be a promising source of treatments for the management of chronic pain, as an example the terpenes.

PURPOSE

The aim of this study was to evaluate the anti-nociceptive and anti-inflammatory effects of one of these terpenes, d-limonene (LIM - a common monoterpene found in citrus fruits) alone and complexed with hydroxypropyl-β-cyclodextrin (LIM/HPβCD) in preclinical animal models.

METHODS

Orofacial pain was induced by the administration of hypertonic saline on the corneal surface, the injection of formalin into the temporomandibular joint (TMJ), or chronic constriction injury of the infraorbital nerve (CCI-IoN). The study used male Wistar rats and Swiss mice treated with LIM (50 mg/kg), LIM/HPβCD (50 mg/kg), vehicle (control), gabapentin or morphine, and eyes wiping (induced by hypertonic saline), face rubbing (formalin-induced in TMJ) or mechanical hyperalgesia (provoked by CCI-IoN) were assessed. Additionally, ELISA was used to measure TNF-α, and western blot analysis to assess levels of PKAcα, NFκB, p38MAPK and phosphorylated PKC substrates. Serum levels of aspartate aminotransferase (AST) and alanine transferase (ALT) were also evaluated.

RESULTS

LIM and LIM/HPβCD significantly reduced (p < 0.001) corneal nociception and formalin-induced TMJ nociception. In addition, both substances attenuated (p < 0.001) mechanical hyperalgesia in the CCI-IoN model. The antinociceptive effect induced by LIM and HPβCD/LIM was associated with decreased TNF-α levels, downregulation of the NFκB and p38MAPK signalling pathways and reduced PKC substrate phosphorylation and PKA immunocontent. Moreover, the results demonstrated that complexation with HPβCD was able to decrease the therapeutic dose of LIM.

CONCLUSION

LIM was found to be a promising molecule for the treatment of orofacial pain due to its capacity to modulate some important mediators essential to the establishment of pain, and HPβCD can be a key tool to improve the profile of LIM.

Special Screening Resources: Strategies to Identify Substance Use Disorders, Including Opioid Misuse and Abuse

The prescription drug crisis has affected all sectors of the population, and so it is inevitable that dentists will increasingly see at-risk patients or those with substance use disorders in the course of their professional activities. Recognizing these patients and the special needs that they may have is now part of the standard of care for the profession. Screening for substance misuse involves a thorough history and review of the patient's medical record and, as appropriate, reviewing prior records and use of available screening tools.

Comorbid Conditions in Relation to Controlled Substance Abuse

Dental patients who experience comorbid psychiatric and medical conditions present an elevated risk of medication misuse, abuse, substance use disorders, and overdose. The authors review the role of notable comorbidities in predicting the development of substance use disorder, including medical, psychiatric, and other psychosocial factors that can be assessed in general dental practice. Psychiatric disorders commonly cooccur with substance abuse, and these typically include anxiety disorders, mood disorders (major depression, bipolar), posttraumatic stress, as well as sleep and eating disorders. Medical disorders commonly found to be present with substance use disorders are also reviewed, including common cardiovascular and pulmonary disorders.

Assessment and Management of the High-Risk Dental Patient with Active Substance Use Disorder

Every dentist cares for patients with a history of substance use disorder (SUD), regardless of a patient's socioeconomic status, education, or ethnicity. SUD is a global epidemic, with approximately 8% of the general US population meeting diagnostic criteria for a SUD and more than 20% of the global population experiencing a SUD. The importance of understanding how to identify substance use, manage patients with a SUD, and offer appropriate referral is essential for all dental professionals. In 2005, the American Dental Association published, "Statement on Provision of Dental Treatment for Patients with Substance Use Disorders."

Patient Interviewing Strategies to Recognize Substance Use, Misuse, and Abuse in the Dental Setting

Brief and effective clinical interviewing is critical for identifying patient risk factors, including those associated with substance use. Dental practitioners may perceive identifying patient substance misuse and abuse as a complex undertaking or may consider this clinical assessment beyond the scope of their training and practice. This article describes interviewing strategies that will help dental providers communicate effectively and empathically with their patients to collect relevant clinical information related to substance use, misuse, and abuse and provide better care for their patients.