Transitory paresis of the lateral pterygoid muscle during a posterior superior alveolar nerve block--a case report.

The posterior superior alveolar nerve (PSAN) is a major sensory branch of the maxillary division of the trigeminal nerve. A PSAN block is a dental nerve block used for profound anesthesia of the maxillary molars. Complications arising from the PSAN block include hematoma formation, transient diplopia, blurred vision, and temporary blindness. This article presents a case of temporary paresis in the lateral pterygoid muscle following a PSAN block that utilized a 27-gauge long needle. The anatomical parameters and pathogenesis of such a complication are reviewed.

Etiology of xerostomia and dental caries among methamphetamine abusers.

This study reviews the peripheral effects of methamphetamine on the salivary acini, the pathogenesis of methamphetamine-induced xerostomia, and its anecdotal relationship to dental caries. Methamphetamine is a sympathomimetic central stimulant which is abused for its euphoric effects. Its pharmacological action is exerted indirectly by sustaining high levels of catecholamines in the synaptic cleft and directly by binding to the postsynaptic adrenergic receptors. Methamphetamine abusers report subjective perception of xerostomia, which cannot be explained by the direct peripheral action of methamphetamine on the secretory acini. The drug may cause a decrease in salivary flow rate by centrally inhibiting salivatory nuclei via stimulation of alpha-2 receptors in the brain. Drug mediated dehydration state may influence the perception of dry mouth in abusers. The decreased salivary flow rate, either due to a central inhibitory action of methamphetamine or generalised dehydration, likely contributes to the increased occurrence of dental caries. Five cases of methamphetamine abuse are presented, three of whom experienced rampant dental caries. A direct association between methamphetamine abuse and the occurrence of rampant caries was not clear.

Caries associated with methamphetamine abuse.

Rampant caries is one of the hallmarks of chronic methamphetamine abuse. "Meth" is a potent central nervous system stimulant with physical and psychological effects similar to cocaine. It is the author's opinion that the caries associated with methamphetamine abuse is related to three risk factors: 1) xerostomia caused by the drug; 2) a subsequent increase in sugared soft drink consumption; and 3) lack of oral hygiene during extended periods of abuse. Patients in this risk group usually present for treatment due to severe pain. However, they may be reluctant to discuss their illegal drug habit. Anorexia may also be present. Treatment includes cessation of drug abuse, oral hygiene, restrictions on sugar intake, and daily fluoride supplementation. Such patients tend to exhibit poor compliance with treatment recommendations or fail to show for appointments.