Mucoadhesive, Thermoreversible Hydrogel, Containing Tetracaine-Loaded Nanostructured Lipid Carriers for Topical, Intranasal Needle-Free Anesthesia.

Recent advances have been reported for needle-free local anesthesia in maxillary teeth by administering a nasal spray of tetracaine (TTC) and oxymetazoline, without causing pain, fear, and stress. This work aimed to assess whether a TTC-loaded hybrid system could reduce cytotoxicity, promote sustained permeation, and increase the anesthetic efficacy of TTC for safe, effective, painless, and prolonged analgesia of the maxillary teeth in dental procedures. The hybrid system based on TTC (4%) encapsulated in nanostructured lipid carriers (NLC) and incorporated into a thermoreversible hydrogel of poloxamer 407 (TTCNLC-HG4%) displayed desirable rheological, mechanical, and mucoadhesive properties for topical application in the nasal cavity. Compared to control formulations, the use of TTCNLC-HG4% slowed in vitro permeation of the anesthetic across the nasal mucosa, maintained cytotoxicity against neuroblastoma cells, and provided a three-fold increase in analgesia duration, as observed using the tail-flick test in mice. The results obtained here open up perspectives for future clinical evaluation of the thermoreversible hybrid hydrogel, which contains TTC-loaded NLC, with the aim of creating an effective, topical, intranasal, needle-free anesthesia for use in dentistry.

Resistivity Technique for the Evaluation of the Integrity of Buccal and Esophageal Epithelium Mucosa for In Vitro Permeation Studies: Swine Buccal and Esophageal Mucosa Barrier Models.

Permeation assays are important for the development of topical formulations applied on buccal mucosa. Swine buccal and esophageal epithelia are usually used as barriers for these assays, while frozen epithelia have been used to optimize the experimental setup. However, there is no consensus on these methods. In transdermal studies, barrier integrity has been evaluated by measuring electrical resistance (ER) across the skin, which has been demonstrated to be a simple, fast, safe, and cost-effective method. Therefore, the aims here were to investigate whether ER might also be an effective method to evaluate buccal and esophageal epithelium mucosa integrity for in vitro permeation studies, and to establish a cut-off ER value for each epithelium mucosa model. We further investigated whether buccal epithelium could be substituted by esophageal epithelium in transbuccal permeation studies, and whether their permeability and integrity were affected by freezing at -20 °C for 3 weeks. Fresh and frozen swine buccal and esophageal epithelia were mounted in Franz diffusion cells and were then submitted to ER measurement. Permeation assays were performed using lidocaine hydrochloride as a hydrophilic drug model. ER was shown to be a reliable method for evaluating esophageal and buccal epithelia. The esophageal epithelium presented higher permeability compared to the buccal epithelium. For both epithelia, freezing and storage led to decreased electrical resistivity and increased permeability. We conclude that ER may be safely used to confirm tissue integrity when it is equal to or above 3 kΩ for fresh esophageal mucosa, but not for buccal epithelium mucosa. However, the use of esophageal epithelium in in vitro transmucosal studies could overestimate the absorption of hydrophilic drugs. In addition, fresh samples are recommended for these experiments, especially when hydrophilic drugs are involved.

Local delivery natural products to treat periodontitis: a systematic review and meta-analysis.

OBJECTIVES: This study aimed to answer the PICO question: in adults with periodontitis, does subgingival delivery of natural products (NP) after scaling and root planing (SRP) results in a better reduction of probing pocket depth (PPD) when compared with SRP alone or SRP plus placebo? MATERIAL AND METHODS: A search for trials was carried out in eight databases. Two independent investigators performed all steps of this review. PPD reduction, clinical attachment level (CAL) gain, gingival inflammation, and biofilm accumulation reduction were investigated. We conducted meta-analyses where data could be pooled. RESULTS: Searches yielded 4771 records, in which 27 trials fulfilled the eligibility. There was a large heterogeneity among trials (I2 > 0.69, χ2 < 0.000). Only four studies were at low risk of bias. The evidence quality was very low. The effectiveness of NP was demonstrated in a follow-up of 3-6 months considering PPD reduction (8 trials: 0.72 mm [95%CI: 0.23, 1.22]) and CAL gain (5 trials: 1.07 mm [95%CI: 0.36, 1.78]). A significant reduction in periodontal inflammation favors the use of NP. The biofilm accumulation reduction effect of NP was very weak or non-significant. CONCLUSION: Although the high risk of bias and large heterogeneity of trials impose some restrictions on the validity of effect estimate, this review indicates that adjunctive NP better reduced the PPD when compared to SRP alone or SRP plus placebo in a follow-up of 3-6 months. CLINICAL RELEVANCE: The evidence of non-responsive patients to conventional periodontal therapy highlights the need for therapeutic alternatives to treat periodontitis.

Can local anesthesia with ropivacaine provide postoperative analgesia in extraction of impacted mandibular third molars? A randomized clinical trial.

OBJECTIVE: The aim of this study was to compare the local anesthesia efficacy of ropivacaine 0.75% compared to lidocaine 2% with 1:100,000 epinephrine for postoperative analgesia following extraction of impacted mandibular third molars. STUDY DESIGN: In this randomized, double-blind crossover clinical trial, 30 participants underwent surgical removal of bilateral impacted mandibular third molars under local anesthesia using ropivacaine 0.75% or lidocaine 2% with 1:100,000 epinephrine. The pain was recorded on a visual analog scale at 4, 8, 12, 24, and 48 h postoperatively. The use of analgesics and the presence of adverse effects were recorded. RESULTS: The duration of soft tissue anesthesia in the ropivacaine group was significantly longer than that in the lidocaine group. The lidocaine group recorded significantly higher visual analog scale scores at all postoperative time intervals, except in the final 48-h period. Analgesic use was higher in the lidocaine group. Rescue medication was used by 2 patients in each group (6.7%). Significantly more postoperative bleeding was seen in the ropivacaine group. CONCLUSION: Ropivacaine 0.75% injection before the surgical procedure may be associated with preventive analgesia for extraction of impacted mandibular third molars.

Comparison of two vasoconstrictors on glycemic levels in diabetic patients.

OBJECTIVES: The aim of this study was to evaluate glycemic levels in diabetic patients before, during, and after extractions using 2% lidocaine with 1:100,000 epinephrine (Lido/Epi) and 3% prilocaine with 0.03 IU/mL felypressin (Prilo/Fely). MATERIALS AND METHODS: A double-blind, randomized clinical trial was conducted to evaluate changes in body parameters and glycemic levels in diabetic patients undergoing two anesthetic protocols during dental extractions. During surgery, we evaluated blood pressure (BP), heart rate (HR), saturation (SpO2), and capillary glycemic levels (Gly). These parameters were measured at the following surgical moments: basal, 30 min after medication, incision, tooth removal, suture, and 30 and 60 min after anesthesia. RESULTS: Data analysis showed no differences between the groups considering age, weight, and time spent in surgery. Increased systolic BP and decreased diastolic BP were observed in the lido/epi group. No difference was observed in the prilo/fely group among the surgical moments or between the groups regarding BP. No difference was observed in HR and SpO2 between the groups at any surgical moment. However, differences were found when compared the differences in glycemic and basal levels in both groups with greater decreases in blood glucose values for the lido/epi group. In anxiety level evaluation, there was no difference between the different surgical moments. CONCLUSION: Thus, both lido/epi and prilo/fely (maximum 3.6 mL) can be safely used in controlled diabetic patients CLINICAL RELEVANCE: The use of lidocaine associated with epinephrine did not increase glycemic levels but leads to decrease over time when associated with an anxiety reduction protocol, offering some advantage over prilocaine plus felypressin for diabetic patients.