Development of amitriptyline buccoadhesive tablets for management of pain in dental procedures

Drug Delivery Platforms Containing Thermoresponsive Polymers and Mucoadhesive Cellulose Derivatives: A Review of Patents

Nowadays, the development of mucoadhesive systems for drug delivery has gained keen interest, with enormous potential in applications through different routes. Mucoadhesion characterizes an attractive interaction between the pharmaceutical dosage form and the mucosal surface. Many polymers have shown the ability to interact with mucus, increasing the residence time of local and/or systemic administered preparations, such as tablets, patches, semi-solids, and micro and nanoparticles. Cellulose is the most abundant polymer on the earth. It is widely used in the pharmaceutical industry as an inert pharmaceutical ingredient, mainly in its covalently modified forms: methylcellulose, ethylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose, and carboxymethylcellulose salts. Aiming to overcome the drawbacks of oral, ocular, nasal, vaginal, and rectal routes and thereby maintaining patient compliance, innovative polymer blends have gained the interest of the pharmaceutical industry. Combining mucoadhesive and thermoresponsive polymers allows for simultaneous in situ gelation and mucoadhesion, thus enhancing the retention of the system at the site of administration and drug availability. Thermoresponsive polymers have the ability to change physicochemical properties triggered by temperature, which is particularly interesting considering the physiological temperature. The present review provides an analysis of the main characteristics and applications of cellulose derivatives as mucoadhesive polymers and their use in blends together with thermoresponsive polymers, aiming at platforms for drug delivery. Patents were reviewed, categorized, and discussed, focusing on the applications and pharmaceutical dosage forms using this innovative strategy. This review manuscript also provides a detailed introduction to the topic and a perspective on further developments.

Topic delivery of analgesics in oral surgery

Introduction: Following any oral surgery procedure, postoperative pain is an inevitable outcome and can be described as moderate to severe. The pain management is essential for the comfort and the well-being of the patients. Topical delivery and more specifically transmucosal delivery systems seem to be of great value for the development of new pain management strategies. Method: A systematic literature review was performed using PubMedCentral database. Only PubMedCentral indexed publications were selected and included if they described i) a human clinical study with pharmacokinetic and/or pain relief assessment a biomaterial for topic delivery, ii) the delivery of analgesics or NSAIDs for analgesic purpose and iii) a biomaterial for topic delivery. Results: Ten articles were selected among which 4 pharmacokinetic studies and 8 studies describing pain relief. Six of the selected articles were well defined with a good scientific level of evidence (level 2) and 4 of them with a low level of evidence. Discussion: The clinical investigations demonstrated a good analgesia, a rapid pain relief with a decrease of the administered doses compared to the oral administration. Moreover, these topic analgesics were well tolerated by the patients. Number of devices was developed for the topical delivery after oral surgery procedures. Excepting a gelatin sponge and a hydro alcoholic gel, most of the devices were made of cellulose and its derivatives. Authors reported that the materials showed a good maintenance at the site of application and the release of the analgesic was well controlled over the time. Conclusion: However, well conducted large clinical trials are still missing in order to validate the absence of side effects.

Use of antidepressants in dentistry: A systematic review

OBJECTIVE

Previous research has suggested that antidepressants can be used in oral health care. The aim of this systematic review was to search for scientific evidence of the efficacy of the use of antidepressants in dentistry.

MATERIALS AND METHODS

The clinical question was as follows (PICO question): dentistry patients (Patients); antidepressants (Intervention); no use or placebo or other drug (Comparison); and efficacy in oral health problems (Outcome). An electronic search was conducted in seven databases, as well as a manual search without restriction regarding language and date of publication. Two independent reviewers selected studies based on eligibility criteria, extracted data and assessed methodological quality based on the PEDro scale. The PROSPERO record is number CRD42016037442.

RESULTS

A total of 15 randomized controlled trials were associated with the use of antidepressants to control chronic or acute pain in dentistry, among other conditions such as bruxism and burning mouth syndrome. The most commonly used drug in clinical trials was amitriptyline (more than 50% of studies).

CONCLUSIONS

Antidepressants may be effective in dentistry for acute and chronic pain, but there is a large amount of methodological heterogeneity among the evaluated studies. In summary, there is rationality for the indication of this class of medicine in dentistry in specific clinical situations.

Optimization of piribedil mucoadhesive tablets for efficient therapy of Parkinson's disease: physical characterization and ex vivo drug permeation through buccal mucosa

OBJECTIVE

The aim of this study was optimization of buccal piribedil (PR) mucoadhesive tablets to improve its low bioavailability and provide controlled release for the treatment of Parkinson's disease.

METHODS

Buccal tablets were prepared by direct compression method using carbomer (CP), carboxymethyl cellulose (CMC), and hydroxypropyl methylcellulose (HPMC) as mucoadhesive polymers. Physical properties of powder mixtures and buccal tablets were evaluated. Physicochemical compatibility between ingredients was investigated with infrared spectroscopy and differential scanning calorimetry analysis. In vitro dissolution profiles and drug release kinetics of buccal tablets were investigated. Mucoadhesion and ex vivo permeation studies were performed using sheep buccal mucosa.

RESULTS

Powder mixtures demonstrated sufficient flow properties and physical characteristics of all tablet formulations were within compendia limits. Tablet ingredients were absent of any chemical interactions. CP tablets displayed slower drug release compared to HPMC tablets with zero order release, while CMC tablets lost their integrity and released entire drug after 6 h following Higuchi model. All formulations displayed adequate mucoadhesion and steady state flux of PR through buccal mucosa were higher with HPMC compared to CP-containing tablets.

CONCLUSION

Overall, HPMC was found to combine desired controlled release and mucoadhesion characteristics with sufficient pharmaceutical quality for optimization of buccal tablets. Piribedil mucoadhesive buccal tablets designed for the first time may introduce a new alternative for the treatment of Parkinson's disease.

Ionic liquids and cellulose: dissolution, chemical modification and preparation of new cellulosic materials

Due to its abundance and a wide range of beneficial physical and chemical properties, cellulose has become very popular in order to produce materials for various applications. This review summarizes the recent advances in the development of new cellulose materials and technologies using ionic liquids. Dissolution of cellulose in ionic liquids has been used to develop new processing technologies, cellulose functionalization methods and new cellulose materials including blends, composites, fibers and ion gels.

Clinical anesthetic effectiveness of intraoral mucoadhesive tablets of amitriptyline in healthy volunteers

PURPOSE

Topical anesthetics are widely used in dentistry. One of their indications is to diminish the pain of the injection of anesthetics. Amitriptyline is a tricyclic antidepressant that provides local anesthetic effects by blocking the sodium channels. The present study was performed in an attempt to assess the anesthetic efficacy of an intraoral mucoadhesive tablet of amitriptyline.

MATERIALS AND METHODS

The present study was performed as a randomized, double-blind, placebo-controlled, clinical trial of 25 healthy female volunteers. The mucoadhesive tablet was randomly placed for 15 minutes on the buccal mucogingival tissue adjacent to the root of the upper lateral incisor, and a placebo was placed on the other side. A 27-gauge needle was inserted to touch the alveolar periosteum of the designated site. The pain intensity associated with the stimulation was evaluated every 5 minutes after removing the mucoadhesive tablet using a visual analog pain scale and pain rating scoring methods.

RESULTS

The difference between the amitriptyline and placebo groups was statistically significant 20, 25, 30, 35, and 40 minutes after placing the mucoadhesive tablet. Its mean onset and duration of action was 25 and 20 minutes, respectively (P<.05).

CONCLUSIONS

To our knowledge, the present study represents an initial step toward achieving an efficient and safe anesthetic method. The intraoral mucoadhesive amitriptyline tablet proved to be a promising anesthetic device for manipulating pain in dental procedures. However, it should also be mentioned that to achieve high efficiency, it will be necessary to optimize the release profile.

Influence of pH modifiers and HPMC viscosity grades on nicotine-magnesium aluminum silicate complex-loaded buccal matrix tablets

Hydroxypropyl methylcellulose (HPMC) tablets containing nicotine-magnesium aluminum silicate (NCT-MAS) complex particles and pH modifiers, namely, sodium chloride, citric acid, and magnesium hydroxide, were prepared using the direct compression method. The effects of HPMC viscosity grades and pH modifiers on NCT release and permeation of the matrix tablets were examined. The results showed that the higher the viscosity grade of HPMC that was used in the tablets, the lower was the unidirectional NCT release rate found. The unidirectional NCT permeation was not affected by the viscosity grade of HPMC because the NCT diffusion through the mucosal membrane was the rate-limiting step of the permeation. Incorporation of magnesium hydroxide could retard NCT release, whereas the enhancement of unidirectional NCT release was found in the tablets containing citric acid. Citric acid could inhibit NCT permeation due to the formation of protonated NCT in the swollen tablets at an acidic pH. Conversely, the NCT permeation rate increased with the use of magnesium hydroxide as a result of the neutral NCT that formed at a basic microenvironmental pH. The swollen HPMC tablets, with or without pH modifiers, gave sufficient adhesion to the mucosal membrane. Furthermore, the addition of magnesium hydroxide to the matrix tablets was the major factor in controlling buccal delivery of NCT. This study suggests that the NCT-MAS complex-loaded HPMC tablets, which contained magnesium hydroxide, are potential buccal delivery systems of NCT.