agar and Pain

To provide safe dental care, it is important to minimize the pain associated with the initial injection of the local anesthetic. For this purpose, a topical anesthetic is preliminarily applied to the area where a needle will be inserted in a clinical setting. In this study, we prepared new topical anesthetic formulations with favorable intra-oral retentivity and an excellent anesthetic effect, and clinically evaluated their efficacy. We used 4% lidocaine solution as an anesthetic drug and gelatin, agar, and a food thickener as a base to prepare new topical anesthetic formulations. The subjects rested in a supine position on a chair for dental practice prior to the following experiments. Firstly, about 0.2 g of the sample was applied at a test site. One minute later, the sample was removed, and a 30 G dental injection needle was inserted into the test site. The agar/gelatin-based formulation containing gelatin of 2% and agar of 1% had a moderate solidity at 25°C and a moderate fluidity at 37°C. This formulation showed a significantly greater depth than any of the commercially available topical anesthetics. The results of the present study demonstrated that the agar/gelatin-based formulation showed an excellent analgesic effect against pain associated with needle insertion.

Topics: Adult; Agar; Anesthetics, Local; Dental Care; Double-Blind Method; Female; Gelatin; Humans; Injections; Lidocaine; Male; Needles; Pain; Pain Measurement

To report a new entity called "toxic non-inflammatory fungal keratitis.". Eyes manifesting infective keratitis with a history of prior administration of topical steroids were included in the study. The details pertaining to the type of injury, duration of injury, and primary treatment for corneal trauma were meticulously documented. The corneal tissues were scraped from the patients and were analyzed for fungal filaments by using a 10% KOH mount under a compound microscope. Moreover, these scraped materials were plated on blood agar and Sabouraud dextrose agar plates.. The corneal ulcers displayed a disproportionately reduced intensity of pain and improved visual acuity. Further, 10% KOH revealed profuse fungal filaments with few inflammatory cells in all the patients. The anterior chamber cells and flare were either reduced or entirely absent. There was no evidence of lid edema and surrounding corneal edema in any of the patients. The mean healing period was 28.8 days (standard deviation (SD): 10.05). The KOH mount revealed the presence of confluent fungal hyphae with a few inflammatory cell infiltrates. The Aspergillus species and Fusarium species were found in 47% and 40% of the cases, respectively.. Toxic non-inflammatory fungal keratitis following steroid therapy needs to be considered in fungal ulcers with disproportionately less pain and good visual acuity. The fungal ulcers with altered clinical signs of classical inflammation need to be assessed for topical steroid misuse.

Topics: Agar; Cornea; Corneal Ulcer; Eye Infections, Fungal; Fungi; Humans; Keratitis; Pain; Steroids; Ulcer

The present study is the first demonstration of prolonged nociceptive behavior in the trigeminal region following compression of the trigeminal ganglion in rats. Experiments were carried out on male Sprague-Dawley rats mounted onto a stereotaxic frame under pentobarbital sodium anesthesia. For compression of the trigeminal ganglion, a 4% agar solution (8microl) was injected into the trigeminal ganglion through a stainless steel injector (24 gauge), which extended 2mm beyond the end of a guide cannula (21 gauge). Following agar injection, the injector and guide cannula were removed. In the control group, rats were sham operated without agar injection. Air-puff thresholds (mechanical allodynia), pin prick responses (mechanical hyperalgesia), and spontaneous scratching behavior were examined 3 days before surgery and at 3, 7, 10, 14, 17, 21, 24, 30, and 40 days after surgery. Data were analyzed using a repeated measures ANOVA followed by multiple group comparisons using the LSD post-hoc test. Air-puff thresholds significantly decreased after compression of the trigeminal ganglion. Mechanical allodynia was established within 3 days and lasted beyond postoperative day 24. Mechanical hyperalgesia was also evident 3 days after compression and persisted until the 40th postoperative day. Although mechanical allodynia and hyperalgesia appeared bilaterally, the ipsilateral side was significantly more sensitive. Intraperitoneal treatment with carbamazepine significantly blocked mechanical allodynia produced by compression of the trigeminal ganglion. These findings suggest that prolonged nociceptive behavior following compression of the trigeminal ganglion may mimic trigeminal neuralgia in this animal model.

Topics: Agar; Analgesics, Non-Narcotic; Animals; Behavior, Animal; Body Weight; Carbamazepine; Facial Pain; Functional Laterality; Grooming; Hyperalgesia; Male; Pain; Pain Measurement; Physical Stimulation; Postural Balance; Pressure; Rats; Rats, Sprague-Dawley; Trigeminal Ganglion; Trigeminal Neuralgia