A new protocol to evaluate the effect of topical anesthesia.

This double-blind, placebo-controlled, randomized cross-over clinical experimental study tested the reliability, validity, and sensitivity to change of punctuate pain thresholds and self-reported pain on needle penetration. Female subjects without orofacial pain were tested in 2 sessions at 1- to 2-week intervals. The test site was the mucobuccal fold adjacent to the first upper right premolar. Active lidocaine hydrochloride 2% (Dynexan) or placebo gel was applied for 5 minutes, and sensory testing was performed before and after application. The standardized quantitative sensory test protocol included mechanical pain threshold (MPT), pressure pain threshold (PPT), mechanical pain sensitivity (MPS), and needle penetration sensitivity (NPS) assessments. Twenty-nine subjects, mean (SD) age 29.0 (10.2) years, completed the study. Test-retest reliability intraclass correlation coefficient at 10-minute intervals between examinations was MPT 0.69, PPT 0.79, MPS 0.72, and NPS 0.86. A high correlation was found between NPS and MPS (r = 0.84; P < .001), whereas NPS and PPT were not significantly correlated. The study found good to excellent test-retest reliability for all measures. None of the sensory measures detected changes in sensitivity following lidocaine 2% or placebo gel. Electronic von Frey assessments of MPT/MPS on oral mucosa have good validity.

The effect of sonophoresis on topical anesthesia: a pilot project.

The dental anesthesia sonophoresis device (DASD) is a novel device that is intended to reduce the discomfort associated with intraoral mucosa needle puncture. The DASD produces ultrasonic energy that provides a sonophoretic effect on the oral mucosa, generating microchannels through the lipids between the keratinized cells that make up the stratum corneum. Once the topical anesthetic has permeated the stratum corneum, it quickly diffuses through the soft tissue, desensitizing the nerve endings and reducing the perception of pain caused by needle penetration. The aim of this study is to evaluate whether topical anesthesia applied using the DASD will reduce the discomfort of the needle puncture when compared to the control device. A split-mouth model, using 50 healthy subjects with puncture site at the maxillary canine vestibule, was used for this study. Subjects received a needle puncture on both sides of the mouth. Prior to the needle puncture, there was randomized application of 5% lidocaine with the DASD and a control device. Subjects rated their discomfort after needle punctures utilizing the visual analog scale pain scoring system. There was no statistically significant difference in the pain perception using the DASD versus the control device.

A comparative study of children's pain reactions and perceptions to AMSA injection using CCLAD versus traditional injections.

UNLABELLED: Pain control is an important part of dentistry, particularly in pediatric dentistry. Recently, a computer-controlled local anesthetic delivery system (CCLAD) has been developed to reduce pain related to the local anesthetic injection. In conjunction with this technology, a new approach to the anterior and middle superior alveolar nerves (AMSA) has been induced. Studies evaluating the CCLAD in pediatric dentistry showed variable results regarding its use in pediatric dentistry. Further evaluation of this technique is needed to provide sound scientific evidence on the use of the CCLAD at this specific injection site in children. AIM: To assess children's pain reactions and pain perceptions of the AMSA injection using the CCLAD compared to the traditional buccal/palatal injections. MATERIALS AND METHODS: Children's pain reactions and perceptions to both techniques were measured in a group of 40 children who received both anesthetic techniques alternatively on two visits. The pain reactions were scored using the SEM scale, whereas the pain perception was evaluated by the Eland color scale. Statistical analysis was carried out using SPSS version 10.0. RESULTS: The AMSA injection delivered with the CCLAD had significantly lower mean pain reaction scores compared to traditional buccal and palatal injections. The prolonged injection time required for delivering the CCLAD injection had no negative impact on the children. The children's pain perception scores when using the CCLAD were also significantly lower compared to the traditional injection. CONCLUSION: The AMSA injection delivered with the CCLAD was found to be a promising device, and had significantly lower pain reaction and perception scores compared to the traditional buccal and palatal injections.

[Etiopathogenic, clinical-diagnostic and therapeutic aspects of the burning mouth syndrome. Research and treatment protocols in a patient group]. / Aspetti eziopatogenetici, clinico-diagnostici e terapeutici della sindrome della bocca bruciante. Protocolli di ricerca e cura su un gruppo di pazienti.

BACKGROUND: Burning mouth syndrome (BMS) is a frequently seen pathology characterised by burning tongue and oral pain without macroscopic structural lesions to the mucose. BMS etiopathology isn't known and therapy is merely empirical and unsatisfactory. METHODS: To evaluate the hypothesis that this syndrome would originate by a small diameter peripheral neuropathy combined to a mucosal trophic lesion, 37 patients, (7 male, 30 female, between 36 and 79 years, mean 54 years) affected by BMS, consecutively observed in our dispensary were submitted to a series of examinations and to therapeutical approach used in neuropathic painful syndromes. All patients were submitted to a complete stomatological exam and X-ray pantomography to exclude mucosal macroscopical lesions and dentistry illnesses. All patients executed sierological exams (glycemia, etc.), neurological exam, tongue and foot dorsum quantitative sensory examination, tongue and face telethermography. A few patients (3 male, 10 female; age 34 to 53, mean 49) were submitted to mucosal tongue biopsy, analyzed by optic microscopy and immunofluorescency following treatment with anticytoplasmatic neuronal proteins antibodies (protein gene product 9.5). RESULTS: These examinations showed subclinical polyneuropathy in 50% of patients. In particular, a loss of function in small diameter nervous fibres in about 50% of patients was observed. Histological examination of tongue mucose revealed a moderate atrophy in 70% patients. CONCLUSIONS: All patients were submitted to an antalgic therapy, with non-antiflammatory drugs used in neuropathic painful syndromes (quercetine, antiepileptic drugs benzodyazepinein and gabaergic, topical application of capsaicine solutions).

Activation of neurons in rat trigeminal subnucleus caudalis by different irritant chemicals applied to oral or ocular mucosa.

To investigate the role of trigeminal subnucleus caudalis in neural mechanisms of irritation, we recorded single-unit responses to application of a variety of irritant chemicals to the tongue or ocular mucosa in thiopental-anesthetized rats. Recordings were made from wide dynamic range (WDR) and nociceptive-specific units in superficial layers of the dorsomedial caudalis (0-3 mm caudal to obex) responsive to mechanical stimulation and noxious heating of the ipsilateral tongue ("tongue" units) and from WDR units in ventrolateral caudalis (0-2 caudal to obex) responsive to mechanical and noxious thermal stimulation of cornea-conjunctiva and frequently also surrounding skin ("cornea-conjunctival" units). The following chemicals were delivered topically (0.1 ml) onto the dorsal anterior tongue or instilled into the ipsilateral eye: capsaicin (0.001-1% = 3.3 x 10(-2) to 3.3 x 10(-5) M), ethanol (15-80%), histamine (0.01-10% = 9 x 10(-1) to 9 x 10(-4) M), mustard oil (allyl-isothiocyanate, 4-100% = 4 x 10(-1) to 10 M), NaCl (0.5-5 M), nicotine (0.01-10% = 6 x 10(-1) to 6 x 10(-4) M), acidified phosphate buffer (pH 1-6), piperine (0.01-1% = 3.5 x 10(-2) to 3.5 x 10(-4) M), serotonin (5-HT; 0.3-3% = 1.4 x 10(-1) to 1.4 x 10(-2) M), and carbonated water. The dose-response relationship and possible tachyphylaxis were tested for each chemical. Of 32 tongue units, 31 responded to one or more, and frequently all, chemicals tested. The population responded to 75.3% of the various chemicals tested (

Oral mucosal stimulation modulates intensity of breathlessness induced in normal subjects.

Patients with chronic obstructive pulmonary disease (COPD) often report an increase in breathlessness when they breathe through a mouthpiece. We hypothesized that stimulation of receptors in the oral mucosa modulates the sensation of breathlessness. We studied 10 normal naive volunteers in whom breathlessness was induced by having them breathe for 4 min with an inspiratory resistive load (18 cm H2O/L/s) while breathing was stimulated by CO2 inhalation (end-tidal PCO2 maintained at 55 mm Hg). Initially, subjects breathed with a tight-fitting face mask and inspiratory flow was displayed on a storage oscilloscope. In subsequent trials, the subjects were asked to match this trace, which controlled ventilation and the pattern of breathing. Subjects performed eight trials, four with the tight-fitting mask only (M) and four with a mouthpiece and the mask (MM). M and MM were alternated; the initial condition was chosen at random. Following each of the trials, subjects rated the intensity of their breathlessness by choosing a number from a modified Borg scale. On the average, subjects were more breathless while breathing with the mask and mouthpiece than with the mask alone (mean ratings of breathlessness 6.6 +/- 1.1 and 5.6 +/- 1.8 units, p less than 0.01). Six subjects repeated the protocol on 2 additional days: 1 day with inhalation of warm (34 degrees C), humidified air and 1 day after topical application of 4% lidocaine to the oral mucosa. Both these interventions abolished the differences in breathlessness between mask and mouthpiece and mask alone. We conclude that afferent information from oral mucosal stimulation influences the intensity of breathlessness.

The contribution of the nasopalatine nerve to sensation of the hard palate.

This study investigates which areas of the hard palate are innervated by the nasopalatine nerve and determines whether division of this nerve results in a detectable alteration in sensation. In the first part of this study the area of the hard palate from which sharp and blunt sensation could be evoked was investigated in 20 subjects after anaesthetising both anterior (formerly greater) palatine nerves. Sensation remained in the region of the incisive papilla and gingival margin of the central incisors in all patients and, in some, extended as far back as the first premolars. In the second part of the study, sharp and blunt sensation of the hard palate were tested before and after incisive bundle division. No significant alteration in sensation was found in any of the 20 patients tested.