Transoral sialolitectomy combined with sialoendoscopy versus open submaxilectomy for the management of hilar lithiasis of the submandibular gland. / Sialolitectomía transoral combinada con sialoendoscopia versus submaxilectomía abierta para el manejo de litiasis hiliares de la glándula submaxilar.

INTRODUCTION: The treatment of salivary obstructive pathology by minimally invasive techniques has been an object of assessment by different studies for decades. Lithiasis at the level of the salivary duct will be the most frequent cause of obstruction, representing more than 50% of the pathology of the major salivary glands and almost 80% of these affecting the Wharton duct. MATERIAL AND METHODS: A prospective study comparing the results of combined transoral sialolitectomy (CTS) and open submaxillectomy techniques by cervicotomy in 2 groups of patients treated by lithiasis at the level of the hilum of the submaxillary gland. RESULTS: 22 patients were included in the study 16 (72.7%) were men and 6 (27.3%) were women, the average age was 54.41 years ± 12.75 (Min: 30/Max: 77). Regarding the variables associated with the disease: average lithiasis, size of the stone, hospital stay, lingual nerve alteration or complications for both techniques, differences were not found between both groups. There were only statistically significant differences in the average stay in favor of the CTS (P=.001). CONCLUSION: The minimally invasive approaches to the salivary ductal system, associated or not with sialoendoscopy, can be efficacy and can be associated with lower number of complications. The natural tendency should be aimed to gradually replacing open sialoadenectomy techniques, reserving its indication for the treatment of tumor pathology.

Electrostimulation of the lingual nerve by an intraoral device may lead to salivary gland regeneration: A case series study

BACKGROUND: Salivary gland function is controlled by the salivary reflex, whose efferent arm is composed by the parasympathetic and the sympathetic divisions of the autonomic nervous system. Parenchymal injury is the main salivary gland involvement of Sjögren's syndrome and head and neck radiotherapy, but neural damage has been reported as well. Recently an intraoral device for electrostimulation of the lingual nerve in vicinity to the lower third molar has been introduced. At this point this nerve carries efferent fibers for the innervation of the submandibular, sublingual and several minor salivary glands and afferent fibers of the salivary reflex. Therefore, excitation of these fibers potentially leads to increased secretion of all salivary glands. Thus, the study objective was to assess whether comprehensive neural activation by electrostimulation of the lingual nerve carries the potential to induce the regeneration of damaged salivary glands. MATERIAL AND METHODS: The device was tested on three patients with no collectable resting and stimulated secretion of saliva during a double blind, sham controlled period of two months and nine open-label months. RESULTS: All three subjects developed the capacity to spit saliva, not only in direct response to the electrostimulation but also after free intervals without electrostimulation. In addition, their symptoms of dry mouth severity and frequency improved. CONCLUSIONS: This recovery is probably due to the combined effect of increase in secretory functional gland mass and regain of nervous control of the secretory elements and blood vessels. Both are phenomena that would contribute to gland regeneration

Assessment of lingual nerve functions after smoking cessation.

OBJECTIVE: Cigarette smoking is associated with a variety of oral diseases. A previous study showed a reduction of thermal sensitivity in the innervation area of the lingual nerve in smokers possibly caused by a degeneration of thermosensitive receptors as a consequence of smoking. The current study investigates somatosensory changes in ex-smokers. MATERIALS AND METHODS: Sensory functions in innervation areas of lingual nerve were investigated in 40 ex-smokers by psychophysical means. Functions of lingual nerve in 40 ex-smokers were compared to those in 40 smokers and 40 non-smokers. Subjects were investigated using quantitative sensory testing (QST, cold and warm detection, thermal sensory limen, heat and cold pain, and mechanical detection). RESULTS: Significant differences were found in both groups, ex-smokers and smokers compared to non-smokers. Cold (p < .001), warm (ex-smokers: p < .01; smokers: p < .001) detection thresholds and thermal sensory limen (p < .001) showed significantly lower sensitivity in ex-smokers and smokers in comparison to non-smokers. CONCLUSIONS: The lower temperature sensitivity of ex-smokers compared to that in non-smokers indicates a reduction of somatosensory function of the tongue, possibly caused by irreversible nerve degeneration associated with smoking. Influencing factors leading to sensory changes could be modulation of thermo-receptors, demyelination as well as a change of the epithelial structure.

Meta-analysis of the Incidence of Lingual Nerve Deficits After Mandibular Bilateral Sagittal Split Osteotomy.

INTRODUCTION: Bilateral sagittal split osteotomy is a relatively common maxillofacial surgical procedure. The most commonly reported complication is neurosensory disturbances (NSD). The inferior alveolar nerve is by far the most commonly affected but sporadic reports of NSD of the lingual nerve also exist. The aim of this meta-analysis is to estimate the incidence of lingual nerve NSD following bilateral sagittal split osteotomy. MATERIALS AND METHODS: A systematic search of the English literature was conducted in February 2015 including several databases and using numerous MeSH terms. Article selection was based on preset criteria. Then pertinent data were collected and the incidence of the complications was calculated. RESULTS: Three articles were included in the meta-analysis. Incidence rates ranged between 0.3% and 18% with a pooled incidence of 0.7%. DISCUSSION: Lingual nerve NSD is an infrequent complication of bilateral sagittal split osteotomy. Fortunately, the complication usually resolves within 1 year of the procedure.

Duloxetine in the treatment of burning mouth syndrome refractory to conventional treatment: A case report.

Patients with burning mouth syndrome (BMS) report burning sensation and pain involving the tongue and oral mucosa without any apparent medical or dental cause. The pathogenesis of this syndrome remains unclear and there is currently no standard treatment. BMS is, therefore, often misdiagnosed and its management is complex. This lack of clinical expertise may result in decreased health-related quality of life and increased psychological distress among patients with BMS. The present case report involves a 77-year-old female patient with BMS refractory to conventional treatment with nerve block and medication, who was successfully treated with duloxetine. Duloxetine may become a new therapeutic option in the management of BMS.

Lingual nerve neuropraxia following use of the Laryngeal Mask Airway Supreme.

Cranial nerve injury is a rare complication with the use of supraglottic airway devices. A case of lingual nerve injury following the use of a Laryngeal Mask Airway Supreme in a 45 year old woman is presented. A review of the literature regarding lingual nerve injury as a complication of the supraglottic airway is also presented.

Anaesthesia of the inferior alveolar and lingual nerves following subcondylar fractures of the mandible.

A retrospective chart review of 387 patients with condylar and subcondylar fractures revealed 2 cases of inferior alveolar nerve (IAN) and lingual nerve (LN) anaesthesia following the subcondylar fracture. Only 5 cases have been reported previously. The mechanism of action remains unknown but a review of the literature and an analysis of 120 dry human skulls supported the hypothesis that compression of the mandibular nerve at a high level, close to the foramen ovale, could cause anaesthesia. This complication is rare, because it requires compression at a particular angle. The antero-median angulation of the condyle must be close to the foramen ovale, and the fracture must be a unilaterally displaced fracture. The presence of an enlarged lateral pterygoid plate appeared to enhance the risk of compression. The IAN and LN anaesthesia could be resolved after open reduction of the fracture and IAN and LN anaesthesia constitute a strict indication for an early open fracture reduction.

Pulsed radiofrequency modulation for lingual neuralgia.

Pulsed radiofrequency modulation (PRM) is a minimally invasive procedure that has been used successfully to treat neuropathic pain. Its use to treat lingual neuralgia has not to our knowledge been described previously, and we report a case.

Impaired somatosensation in tongue mucosa of smokers.

Smoking has been indicated as a risk factor for oral diseases and can lead to altered sense of taste. So far, the effects of sensory changes on the tongue are not investigated. In this study, quantitative sensory testing was used to evaluate somatosensory function in the lingual region. Eighty healthy volunteers were investigated (20 smokers, 20 non-smokers). Subjects were bilaterally tested in innervation areas of lingual nerves. Thresholds of cold and warm detection, cold and heat pain, and mechanical detection were determined. As control for systemic, extraoral effects of smoking, tests were additionally performed in 40 volunteers (20 smokers, 20 non-smokers) on the skin of the chin innervated by the mental branch of the trigeminal nerve. Cold (p < 0.001), warm detection thresholds (p < 0.001), and thermal sensory limen (p < 0.001) showed higher sensitivity in non-smokers as compared to smokers. Heat pain and mechanical detection, as well as all tests in the skin of the chin, showed no significant differences. The impaired temperature perception in smokers indicates a reduction of somatosensory functions in the tongue, possibly caused by nerve degeneration associated with smoking. Possible systemic effects of smoking do not seem to affect extraoral trigeminal branches.

Verification of nerve integrity after surgical intervention using quantitative sensory testing.

PURPOSE: The aim of this study was to apply a standardized Quantitative Sensory Testing (QST) approach in patients to investigate whether oral surgery can lead to sensory changes, even if the patients do not report any sensory disturbances. Furthermore, this study determines the degree and duration of possible neuronal hyperexcitability due to local inflammatory trauma after oral surgery. PATIENTS AND METHODS: Orofacial sensory functions were investigated by psychophysical means in 60 patients (30 male, 30 female) in innervation areas of infraorbital nerves, mental nerves and lingual nerves after different interventions in oral surgery. The patients were tested 1 week, 4 weeks, 7 weeks, and 10 weeks postoperatively. As controls for bilateral sensory changes after unilateral surgery, tests were additionally performed in 20 volunteers who did not have any dental restorations. RESULTS: No differences were found between the control group and the control side of the patients. Although not 1 of the patients reported paresthesia or other sensory changes postoperatively, QST detected significant differences between the control and the test side in the mental and lingual regions. Test sides were significantly less sensitive for thermal parameters (cold, warm, and heat). No differences were found in the infraorbital region. Patients showed significantly decreased pain pressure thresholds on the operated side. QST monitored recovery over time in all patients. CONCLUSIONS: The results show that oral surgery can lead to sensory deficits in the mental and lingual region, even if the patients do not notice any sensory disturbances. The applied QST battery is a useful tool to investigate trigeminal nerve function in the early postoperative period. In light of the increasing forensic implication, this tool can serve to objectify clinical findings.

Comparison of current perception threshold electrical testing to clinical sensory testing for lingual nerve injuries.

PURPOSE: We performed a retrospective study of lingual nerve injury assessment comparing the techniques of current perception threshold testing versus clinical sensory testing. PATIENTS AND METHODS: We designed and implemented a cross-sectional study and enrolled a patient sample with lingual nerve injuries presenting for treatment to the principal investigator. The predictor variables were clinical sensory testing modalities (ie, temperature, nocioception, vibration, 2-point discrimination, brush stroke, and von Frey monofilament perception). The primary outcome variable was the electrical current perception thresholds of the tongue dorsum (neurometer measurements at 5, 250, and 2,000 Hz). Comparisons were established with the ipsilateral affected and contralateral unaffected lingual nerve distributions. The associations between the clinical sensory testing and current perception threshold measurements were assessed using correlation coefficients, with the level of statistical significance set at P < .05. RESULTS: A total of 40 patients (13 males and 27 females) were included in the present study. The average age of these patients was 34 years (range 13 to 66). Significant correlations were observed between the electrical stimulation thresholds at 2,000 Hz and the 2-point discrimination, reaction to brushing, reaction to vibration, and von Frey fiber thresholds, between the electrical stimulation thresholds at 250 Hz to the nociceptive and thermal thresholds, and between the electrical stimulation thresholds at 5 Hz to thermal stimuli. CONCLUSIONS: The significant correlations observed in the present study indicate that current perception threshold can be a complementary or alternative tool in the assessment and evaluation of lingual nerve injuries.

The role of sensory input of the chorda tympani nerve and the number of fungiform papillae in burning mouth syndrome.

OBJECTIVE: The aim of this study was to evaluate patients suffering from burning mouth syndrome (BMS) and control subjects by means of sensory testing and fungiform papillae count. STUDY DESIGN: The left and right anterior two-thirds of the tongue of of 25 BMS subjects and 20 healthy control subjects were evaluated for electric taste and electric detection threshold. The number of fungiform papillae/cm(2) was evaluated by using close-up digital photography. RESULTS: The electric taste/tingling detection threshold ratio was significantly higher in BMS compared with control subjects (P = .041). No difference was found between the number of fungiform papillae/cm(2) in the BMS compared with the control subjects (P = .277). Patients suffering from BMS for a prolonged period of time presented with a significantly elevated electric taste/tingling detection threshold ratio (P = .031). CONCLUSIONS: BMS may be a neurodegenerative process with chorda tympani nerve hypofunction potentially playing a role in the pathophysiology of this disorder.

Bilateral numb chin syndrome leading to a diagnosis of Burkitt's cell acute lymphocytic leukemia: a case report and literature review.

Numb chin syndrome (NCS), also known as mental nerve neuropathy, is characterized by facial and oral numbness restricted to the distribution of the mental nerve. Although not a common neuropathy, the clinical importance of this syndrome is its frequent association with malignancies, particularly breast cancer and lymphoma. In this paper, we present a rare case of Burkitt cell acute lymphocytic leukemia initially presenting with bilateral NCS. In this case, no abnormalities were detected on initial blood tests and radiologic investigations except for partial loss of lamina dura around mandibular teeth. Furthermore, we found no evidence of any other signs of central nervous system involvement apart from NCS. Nevertheless, the patient continued to experience severe bilateral mandibular pain and paresthesia, prompting us to repeat the blood studies. These showed lymphomatous cells, yielding the diagnosis of leukemia 37 days after the original presentation. When a patient presents with the extremely unusual symptoms of bilateral numbness of lower lip and chin, we should suspect the presence of a malignancy even in the absence of any relevant past history. If the initial radiologic investigations and blood tests reveal no abnormalities, malignancy should not be removed from the differential diagnosis until a definite cause has been found.

Phonetic damage related to unilateral functional inhibition of the lingual nerve.

PURPOSE: The aim of this study was to analyze the effects of unilateral functional inhibition of the lingual nerve in phonetic function by perceptual and acoustic analyses of speech, which was recorded before and after neurosensory modification of the lingual nerve, and a comparison of results of these evaluations with a subject's self-perception. PATIENTS AND METHODS: The sample consisted of 10 volunteers who had the lingual nerve of the right side anesthetized. The analyzed recordings consisted of terms directly dependent on the tongue for production. In the perceptual analysis, pitch and loudness behaviors were observed, in addition to coarticulation and intelligibility. The acoustic analysis of 5 vowels and sibilant /s/ was realized. A questionnaire about the discomfort level in speech production was applied. RESULTS: Perceptual/auditive and acoustic parameters showed no significant differences. Although 3 informants declared some kind of discomfort related to speech production, they presented no acoustic or perceptual modification in sound quality. CONCLUSIONS: Although inhibition of sensory function of the lingual nerve generated considerable annoyance, there was no specific damage to phonetic function in the group under study, because no differences were observed in the quality of the speech of subjects after applying anesthesia to the lingual nerve.

Risk factors of neurosensory deficits in lower third molar surgery: an literature review of prospective studies.

This literature review assessed the risk factors linked to inferior dental nerve (IDN) and lingual nerve (LN) deficits following lower wisdom tooth surgery. A computer search of several databases with specified key words was performed. 32 articles were selected; the risk factors for IDN deficit were reported in 4 articles, LN in 9 and both IDN and LN in 19. Data were analysed statistically to evaluate the potential risk factors. Literature review showed specific radiographic signs and intra-operative IDN exposure increased the risk of IDN deficit. Raising the lingual flap significantly increased the risk of LN deficit. Unerupted tooth and lingual split technique increased IDN and LN deficit risks significantly. Age was linked to IDN and LN deficits, and deep impaction was related to IDN deficit, but no statistical tests were performed on these two risk factors owing to the heterogeneity of data from the studies. This literature review found increased age, unerupted tooth, deep impaction, specific radiographic signs, intra-operative IDN exposure and lingual split technique were risk factors for IDN deficit; increased age, unerupted tooth, distal impaction, raising of lingual flap and lingual split technique were risks factors for LN deficit in lower wisdom tooth surgery.

Chronic restraint stress in rats suppresses sweet and umami taste responses and lingual expression of T1R3 mRNA.

Effects of chronic restraint stress on the taste responses to five basic taste qualities were investigated electrophysiologically in the rat chorda tympani. In addition, the mRNA expression for T1R3, the common G-protein-coupled receptor (GPCR) for sweet and umami tastes, was studied quantitatively by RT-PCR after such stress. Rats were restrained in a small cylindrical restrainer made of steel wire for 8h daily for 14 successive days. The integrated responses to sweet and umami tastes, as recorded from the chorda tympani, were significantly suppressed after such stress, but the other three basic taste responses were unaffected. Expression of T1R3 mRNA in the fungiform papillae, as estimated by RT-PCR, was slightly reduced by the stress, and a quantitative real time RT-PCR study revealed a significant suppression of T1R3 mRNA expression in the stress group. These results suggest that the observed stress-induced changes in taste sensation could be caused by a peripheral disorder of the transduction mechanism in taste-receptor cells, involving in particular a stress-induced inhibition of T1R3 expression.

Oral pain perception and taste in burning mouth syndrome.

BACKGROUND: Aim of this study was to investigate the effect of idiopathic burning mouth syndrome (BMS) on both, the pain perception within trigeminal lingual nerve distribution and gustatory sensitivity using capsaicin threshold test, and regional taste tests, respectively. METHODS: Pain thresholds for capsaicin were assessed using capsaicin-impregnated filter-paper strips. The strips were placed midline on the tongue tip for whole mouth testing with the mouth closed, and on the left or right edge of the extended anterior tongue for lateralized testing. Measures of gustatory function were obtained by validated "taste strips" test kit and electrogustometry. The tests were applied to 13 patients with BMS. Results were compared with those from 28 healthy subjects. RESULTS: Patients with BMS exhibited a decreased gustatory and somatosensory perception compared with healthy controls. These changes were found for lateralized tests but not for the whole mouth test procedure. Duration of disorder showed an effect on the capsaicin threshold, with patients being less sensitive to capsaicin exhibiting an increased duration of disorder. CONCLUSION: Both pain-related and gustatory sensitivies of the tongue are found to be decreased in BMS.

Acoustic and neurophysiologic observations related to lingual nerve impairment.

The purpose of this study was to determine the acoustic effects of lingual nerve impairment on speech. Neurophysiologic examination and thermal quantitative sensory testing (QST) were carried out to determine if the profile, type or severity of sensory nerve impairment had effects on the degree of speech changes. The study group consisted of 5 women and 5 men with lingual nerve damage following an oral and maxillofacial surgery procedure. Time interval between the examination and the nerve damage ranged from 1 month to 20 years. Formants and fundamental frequency and duration of vowel sounds were analyzed. The patients underwent sensory tests, blink reflex and thermal QST of the lingual nerve area. The lingual nerve impairment had effects on the central acoustic features of vowel sounds. A relationship was observed between warm detection threshold values and the magnitude of second formant changes in men. It is concluded that lingual nerve impairment has gender-specific effects on speech. The variability in the acoustic changes of vowel sounds between different patients indicates individual compensatory manners of speech production following lingual nerve impairment.

Effect of SB-750364, a specific TRPV1 receptor antagonist, on injury-induced ectopic discharge in the lingual nerve.

Abnormal neural activity generated at a site of nerve injury is thought to contribute to the development of dysaesthesia. Vanilloid receptor 1 (TRPV1), a transducer of noxious stimuli, may be involved in the initiation of this abnormal activity and could provide a useful therapeutic target. We investigated the effect of a specific TRPV1 antagonist (SB-750364) on injury-induced discharge in the lingual nerve. In 12 anaesthetised adult ferrets the left lingual nerve was sectioned and animals were allowed to recover for 3-7 days. In terminal experiments under general anaesthesia, the nerve was re-exposed and electrophysiological recordings made from spontaneously active axons in fine filaments dissected from the nerve central to both the injury site and the junction with the chorda tympani. SB-750364 was infused via the cephalic vein in order to achieve three increasing but stable systemic blood levels of the compound (0.3, 1.0 and 3.0 microM). Twenty-eight spontaneously active units were studied, with discharge frequencies ranging from 0.02 to 4.9 Hz. There was a significant reduction in spontaneous activity in 17 units (61%) at 1.0 microM or less of SB-750364 (p<0.01; Friedman test with Dunn's multiple comparisons). A further 4 units (14%) showed a significant reduction in activity at 3.0 microM (p<0.01). In the remaining 7 units (25%) the discharge was unaffected (p>0.05). These data show that the TRPV1 antagonist SB-750364 can reduce the level of spontaneous activity initiated in some axons following lingual nerve injury.