Palatoglossal Arch Research Articles

Oral appliances: A successful treatment modality for obstructive sleep apnea category.

Sir, I have read two articles published in your esteemed journal (obstructive sleep apnea [OSA] and metabolic disorders. 2006;8:51-52 and OSA: Diagnosis and Treatment in an Endocrine Clinic. 2006;8:53-55) with great interest. Both of them are very informative and provide immense knowledge about OSA. It is very true that OSA has implications beyond disturbed sleep and yet this disorder remains undiagnosed in a substantial portion of the population especially in developing countries like India. Sir, I would like to bring to your kind notice that although continuous positive airway pressure (CPAP) remains to the gold standard treatment modality for OSA, oral appliances are now gaining popularity. The role of dentists, especially orthodontists and prosthodontists, as part of a multidisciplinary team, in the management of obstructive sleep apnoea is being increasingly recognized. Oral appliances have emerged as a successful modality that modifies the position of tongue or jaw, altering the posterior pharyngeal space. The most-common oral appliance is mandibular advancement device (MAD). MADs came into the market for OSA treatment almost two decades ago. These appliances dilate or open the airway by anterior repositioning of mandible during sleep to relieve snoring and OSA. These devices are especially helpful to patients who are intolerant to their CPAP mask, or for snoring only. The basic mode of function of MAD is related to the mechanical influence of mandibular advancement on pharyngeal patency. Because tongue is connected to mandible, the forward displacement of mandible improves the airway patency of retroglossal space by reducing folds and compression in upper-airway. The retropalatal space and retrolingual space are widened.[1] Lateral wall of the soft palate anatomically connects to the base of the tongue through the palatoglossal arch, so the mandibular advancement stretches the soft palate through the mechanical correction, stiffening the velopharyngeal segment as evidenced by Gakwaya et al. using phrenic nerve magnetic stimulation.[2] Besides dilating the upper-airway and preventing upper-airway obstruction during sleep by holding the mandible in the forced protruded position, MAD sometimes causes undesirable consequences such as dryness of mouth, tooth discomfort or pain, hypersalivation, jaw pain, stiffness or pain of masticatory muscles, occlusal change of tooth position and loosening of teeth. But these are short term, and disappear on removal of appliance. Moreover, jaw pain and stiffness or pains in masticatory muscles are frequently associated with the amount of protrusion of mandible.[3] Usually, MAD is given at 75% of maximum mandibular protrusion but significant decrease in apnea hypopnea index has been found with 50% of maximum mandibular protrusion in mild to moderate OSA cases.[4] Overall advantages of oral appliances over CPAP are: Better-patient compliance than with CPAP Ease of fabrication and good success rate in mild to moderate cases Robust and cost effective therapy Economical for poor patients Easy to handle, care and use.

Intraoral anastomosis of a prelaminated radial forearm flap in reconstruction of a large persistent cleft palate

In this report, we present a case of a prelaminated radial forearm flap in reconstruction of a large persistent cleft palate with transoral single arterial and three venous anastomoses. A 17-years-old female patient presented a large cleft palate defect and complete dentition, dysmelia of both arms and bilateral thumb aplasia. A radial flap was prelaminated using oral mucosa 5 days prior to transplantation. Five days after flap prelamination, the facial artery and vein, submandibular vein, and a venous branch to the masseter muscle behind the buccinator muscle fibers were exposed through an intraoral incision lateral to the inferior right mucogingival junction. The radial artery, its bilateral accompanying veins, and the cephalic vein of transplanted flap were anastomosed transorally to the facial vessels, submandibular vein, and masseter branch. The vessel pedicle ran through the palatoglossal arch dorsal to the second upper molar. Good flow and flap perfusion were evinced, and further-on successful healing was achieved. The case encourages similar treatment in comparable situations avoiding facial nerve hazard and extraoral scars.

Oral metastasis of uterine carcinoma: Case report and 83-year review of this uncommon occurrence

Uterine cervix cancer is the second most common female cancer and the third most common cause of female cancer mortality. The disease spreads into the surrounding tissues by direct infiltration, whereas, spread by hematogenous dissemination is relatively unusual and the involvement of oral and maxillofacial region is extremely rare in gynecological cancer. A 72-year-old Chinese woman was referred to our dental clinic with a 4-month history of a painful and gradually expanding swelling in oral cavity associated with a severe limitation of mouth opening. The submucosa was fibro-elastic with normal mucosal covering on the left side of the soft palate that extended up to the palatoglossal arch, measuring 2.5 cm in maximum diameter. Fine needle aspiration cytology was performed on the nodule and the cytological diagnosis was consistent with undifferentiated carcinoma. An incisional biopsy was performed and the diagnosis of undifferentiated carcinoma of primary unspecified location was made. The patient’s son reported that his mother had been experiencing the return of her “menstrual cycle” so we referred her to the gynecologist who detected a lesion in the cervix uteri, bigger than the one in the oral cavity. Both lesions had the same histological and immunohistochemical profile prompting us to report this case as carcinoma of the cervix uteri that metastasized to the oral cavity. Unfortunately, the patient died 24 months after the initial diagnosis of the oral metastasis. The patient received sessions of radiotherapy exclusively in both lesions. The review of literature showed that oral metastasis from uterine cervix carcinoma is rare, indicating poor prognosis and that the correlation of clinical medical history, laboratory, imagenological, cytological, histopathological and immunohistochemical exams are essential for achievement of the precise diagnosis.

The palatoglossal sphincter in French uvular /r/.

Speech production models have typically defined lingual constrictions in terms of tongue motion relative to unmoving opposing surfaces, such as the palate or teeth. While such a model may apply well to hard structures such as the palate, it is not clear that this appropriately characterizes constrictions involving soft structures such as the velum and uvula. Anatomically, the uvula and velum constitute the upper surface of a muscular sphincter including the palatoglossus muscles laterally and the tongue below. The present study tests whether uvular constrictions may be better described as actions of this palatoglossal sphincter, analogous to the lips, velopharyngeal port, or epilaryngeal tube. We tested this proposal by measuring the response of the velum/uvula during production of French uvular /r/ in an x‐ray film [Munhall et al., J. Acoust. Soc. Am., 98(2), 1222–1224 (1995)]. Preliminary findings indicate that, as seen with other sphincters, speakers exhibit a variety of different mechanisms for forming constrictions, but all show active involvement of the palatoglossal arch, in addition to the tongue, in producing the uvular constriction. Modifications to speech production models to accommodate these findings will be discussed. [Work supported by the NSERC.]

Perforation of and Intubation through the Palatoglossal Fold

Perforation of pharyngeal soft tissues on intubation is rare. We present a case where the endotracheal tube punctured the palatoglossal fold before passing into the trachea. The patient was ventilated for eight days in intensive care before identification of the complication. It is difficult to estimate the frequency of pharyngeal perforation as it rarely occurs. There is however; an increased incidence in difficult intubations, emergency airway management, inexperienced operators and technique used.

Penetrating Injury of the Palatoglossal Arch Associated with Use of the GlideScope® Videolaryngoscope in a Flame Burn Patient

The GlideScope is used to facilitate exposure of the larynx in both routine and difficult airways. A 38-year-old woman with a flame burn (second/third-degree, 40% total body surface area) and inhalation injury accompanied by acute respiratory failure under mechanical ventilation support presented for wound debridement and split thickness skin grafting. After the surgery, the endotracheal tube was reinserted successfully with a GlideScope because we anticipated a problematic airway. However, direct laryngoscopy revealed the endotracheal tube had pierced through the right palatoglossal arch. Because the consulting otolaryngologist confirmed there was no active bleeding, it was decided that no further management was needed for the wound; the patient was re-intubated under direct laryngoscopy. Postoperatively, she was transferred to the intensive care unit of the burn center under mechanical ventilation. This is a report on a rare complication caused by tracheal intubation associated with the use of the GlideScope. We recommend manipulation of the GlideScope should be performed with care under vigilant surveillance to minimize injury to the oropharyngeal tissues when an endotracheal tube is advanced from the mouth to the pharynx. Potential complications should be always kept in mind when the GlideScope is used for intubation.

Post-tonsillectomy dysgeusia with weight loss: possible involvement of soft palate

To demonstrate the importance of detailed, multidisciplinary examination of patients with post-tonsillectomy taste distortions, and to show that post-tonsillectomy dysgeusia may originate in the caudal part of the soft palate. We describe a 29-year-old man who suffered from severe post-tonsillectomy dysgeusia and phantogeusia with secondary weight loss and depression-like symptomatology. The patient had normal electrogustometric thresholds and sensitivity to touch on the posterior tongue. In contrast, elevated taste threshold and reduced sensitivity to touch was found on the caudal part of the soft palate (the palatoglossal arches). More marked elevation of electrogustometric threshold and insensitivity to touch on the right palatoglossal arch correlated with post-operative haemorrhage from the right tonsillar fossa. Psychiatric examination excluded major depression, eating disorders and drug abuse. Dysgeusia constitutes a rare but significant complication of tonsillectomy. Damage to the lingual branch of the glossopharyngeal nerve innervating the posterior tongue is thought to be a major cause of this complication. However, damage to the tonsillar branches of the glossopharyngeal nerve and the soft palate should also be considered as a cause of post-tonsillectomy dysgeusia. Further studies are needed to assess whether post-operative haemorrhage could indicate heightened risk of dysgeusia.

Absence of Hyaline Cartilage in the Tongue of ‘Caspian Miniature Horse’

Histology of the tongue, including apex, root and body, in four adult Caspian miniature horses was examined. Serial sections with 6 mum thickness were stained with haematoxylin-eosin and Masson trichrome and studied under light microscope. The tongue was covered by stratified squamous epithelium. It was thick and keratinized bearing numerous lingual papillae on the dorsum, mostly filiform with a very fine keratinized thread projecting above the surface and bending backward. The fungiform papillae were sparsely scattered among the filiform papillae and covered with keratinized squamous epithelium. Few taste buds were detected on it. The two very large vallate papillae were detected on the dorsum, just rostral to the root, which were covered with stratified squamous epithelium with relatively high amounts of taste buds in the epithelium of the surrounding grooves. The foliate papillae were present near the palatoglossal arch and had a few taste buds. The epithelium covering the ventral surface of the tongue was thin and keratinized. The lingual muscle core consisted of transverse, longitudinal and perpendicular bundles of skeletal muscle fibres. Clusters of minor salivary glands were present between the muscle fibres and lamia propria. Most of the lingual glands were mucous and most of the gustatory ones were serous type. The mid-dorsal special structure of the tongue (dorsal lingual cartilage) contained sparse skeletal muscle fibres and was rich in white adipose tissue. Hyaline cartilage, routinely observed in this structure in the horses, was not detected in Caspian miniature horse.

歯ブラシによる幼児の口腔軟組織損傷例の臨床統計的観察

We studied soft tissue injuries of the oral cavity caused by a toothbrush in 59 children younger than 7 years from 1983 through 2003. There were 35 boys and 24 girls aged 9 months to 6 years 7 months, with a peak incidence at 1 year. Falling down was the cause of injuries in 46 children. Forty-one children visited us directly, whereas others were referred to us by surgeons, emergency specialists, dentists, otolaryngologists, and others. Thirty-one children presented within 3 hours after injury and 15 the following day. The soft palate and palatoglossal arch, buccal mucosa, hard palate, oral floor, retromolar region, upper lip, gingiva, and tongue were involved in 25, 20, 6, 3, 2, 1, 1 and 1 child, respectively. Lacerations greater and less than 10 mm long were seen in 20 and 16 hildren, respectively. Submucous bleeding was present in 13 children, and scratches were present in 10 children. In 3 children, the wound was associated with herniation of the buccal fat pad. The wound was sutured and antibiotics were given to 23 children. Twenty children were observed without antibiotic treatment, and 16 children were given antibiotics. Local infection occurred in 3 children.

Variations in the tensor veli palatini muscle with special reference to its origin and insertion.

Previous research on the tensor veli palatini muscle (TVP) has produced conflicting descriptions of its functions and topographical relationships with other orofacial structures. The goal of this study was to describe the morphology of the TVP in a systematic and comprehensive manner. One hundred nineteen sides of 77 human heads from donated cadavers were partially dissected under a binocular microscope. Histological examination of the hard tissue-muscle interfaces was also undertaken. There were two adjacent origins of the TVP: the cranial base origin (CB origin) and the auditory tube cartilage origin (AT origin). The CB origin always lay anterior to the AT origin and there was no septum or loose tissue between the two muscular laminae leading from these origins. The muscle fibers converged on a central tendinous plate in the muscle belly, which gradually became a common tendon that rounded the pterygoid hamulus before inserting into the palatine aponeurosis. Notably, secondary insertions were found on the maxillary tuber (33.6%) and/or in the submucosal tissue near the palatoglossal arch (37.8%). Maxillary insertions were almost exclusively associated with an AT origin that was wide as or wider than the CB origin. Histological observations confirmed that the hamulus acted purely as a pulley and suggested that a connecting band to the tensor tympani had no or few functions of an intermediate tendon. The TVP appears to act as the dilator tubae and that this function can be maintained by preserving or reconstructing the maxillary insertion during push-back surgery, even if hamulotomy is necessary.

Jaw opening and swallow triggering method for bilateral-brain-damaged patients: K-point stimulation.

The aim of this study was to confirm the response in patients stimulated at the trigger point (K-point). Since we have already clinically encountered patients with hyperactive bite reflexes who were able to open their mouth and swallow after stimulation of the trigger point, we investigated this response in other brain-damaged patients. The trigger point lies on the mucosa lateral to the palatoglossal arch and medial to the pterygomandibular fold at the height of the postretromolar pad. A total of 57 brain-damaged patients, including patients with pseudobulbar palsy due to bilateral upper motor neuron disease and bulbar palsy due to medulla oblongate. Other supratentorial brain-damaged patients and 20 non-brain-damaged subjects were also examined. The subjects were gently stimulated at the trigger point by a finger or a tongue depressor. We found that the pseudobulbar palsy patients with a hyperactive bite reflex responded by mouth opening and swallowing after a jaw movement similar to mastication elicited by the stimulation. The other pseudobulbar palsy patients, who did not have hyperactive bite reflexes and could open their mouth spontaneously, responded by swallowing with jaw movements similar to mastication after the stimulation. The bulbar palsy patients and the supratentorial brain-damaged patients showed no response to the stimulation. The non-brain-damaged subjects also did not respond, but all of the subjects reported a strange sensation after the stimulation. We concluded that stimulating the trigger point was useful for opening the mouth and facilitating swallowing in pseudobulbar palsy patients and that this technique may be of help in these patients in terms of oral health care and feeding.

Morphological characteristics of the tongue and its papillae in the donkey (Equus asinus): a light and scanning electron microscopical study

The morphology of the donkey tongue and its papillae were investigated by macroscopy and by light and scanning electron microscopy in ten adult animals (six males and four females). The spatula-shaped tongues measured about 28 cm in length, 4.5 cm in breadth and 3.5 cm in thickness. Samples from different areas of four tongues were grossly examined and pieces were processed for light and scanning electron microscopy. Filiform papillae were distributed mainly on the dorsum of the tongue, being thin and relatively short at the apex, conical and scaly in the main part (triangular zone) of the body, and thin and longer at the caudal part of the body. Few of them were found on the lateral surfaces. Fungiform papillae appeared scattered mainly on the lateral surfaces. They were mostly rounded (about 1.0 mm in diameter), but lobulated forms were also observed. Filiform and fungiform papillae were both completely devoid of taste buds, indicating a more mechanical function. The vallate papillae were 2-3 in number, located at the most caudal part of the body. They were three to four times as large as the fungiform papillae (about 5.6 mm in diameter) each with a wide circular groove around the central bulbous projection. Secondary grooves originating from the primary one were also demonstrated. The vallate papillae contained many taste buds with taste pores opening deeply into the papillary groove. Fine filiform papillae were demonstrated on the bulb-like part of the vallate papillae. The donkey tongue had sinister and dexter well-developed sets of foliate papillae close to the basis of the palatoglossal arch. They were arranged in the form of numerous leaves separated by deep, variably wide grooves and contained a very large number of taste buds. It is believed that the existence of well developed foliate papillae in donkey may substitute the comparatively few vallate papillae in this species.

Difficult Laryngoscopy Due to the Abnormal Palatoglossal Arch

To the Editor:—The palatoglossal arch curves downward and forward from the soft palate to the tongue and forms the lateral part of the isthmus faucium with the palatopharyngeal arch. We experienced difficult laryngoscopy in a patient with an anatomically abnormal palatoglossal arch.A 15-yr-old boy with mental retardation caused by glycogen-storage disease with frequent hypoglycemic episodes was scheduled for dental treatment during general anesthesia. Premedication consisted of scopolamine and pentazocine. Anesthesia was induced with intravenous midazolam and inhalation of nitrous oxide, oxygen, and sevoflurane. Vecuronium was administered intravenously to facilitate endotracheal intubation. A Macintosh blade was inserted into his mouth and advanced between the right molars and the right side of the tongue. The tongue was about to be displaced to the left to visualize the larynx when the laryngoscopist noticed that it was impossible to displace the base of the tongue with the Macintosh blade. She observed the anatomic relation between the tongue and the pharynx to clarify the reason why the tongue could not be displaced and laryngoscopy was difficult. Her observation of the base of the tongue revealed that the right palatoglossal arch was attached to the dorsal part of the tongue, not to the lateral part (fig. 1). The palatoglossal arch contains the palatoglossus muscle, which originates in the oral surface of the palatine aponeurosis, extends forward, downward, and laterally in front of the palatine tonsil, and enters the lateral part of the tongue, passing deeply and transversely through the tongue with intrinsic transverse muscle fibers. 1The muscle elevates the posterior part of the tongue and pulls down the soft palate, thus constricting the isthmus of fauces and closing off the oral cavity from the oropharynx. 2During ordinary laryngoscopy with the Macintosh blade, the blade was advanced along the right lingual edge toward the right molars and the base of the tongue, then into the pharynx, while the tongue is displaced to the left. However, in this patient, a laryngoscopist could not displace the tongue to the left while advancing the blade along the right lingual edge because the right palatoglossal arch was attached to the dorsal part of the tongue. This anatomic abnormality prevented the displacement of the tongue to the left, which lead to difficult laryngoscopy using the Macintosh blade. The laryngoscopist tried a different method of laryngoscopy without displacement of the tongue to the left. She inserted the Macintosh blade into the open mouth and advanced it forward along the center of the dorsum of the tongue and pushed the base of the tongue upward without displacing it to the left. This maneuver made arytenoid visualization possible. The palatopharyngeal arch, which was located behind the palatoglossal arch, was normal, and there was no abnormality in the relation between these arches. In general, the so-called Mallampati test is available to predict difficult laryngoscopy. 3However, preoperative intraoral examination was difficult in this patient because of mental retardation. Based on our experience, we propose that the abnormal palatoglossal arch should be described as one of the anatomic factors that make laryngoscopy difficult to perform.

口腔症状を主症状とした第２期梅毒の１例

We report a case of secondary syphilis with various oral manifestations. A 26-year-old woman visited our hospital because of lingual pain. The patient had a red and soft verruca at the left angle of the mouth as well as three oval papules on the right side of the tongue. In addition, oral examination revealed marked swelling and redness of bilateral palatal tonsils along with opaline plaque over the palatoglossal arch and inferior surface of tongue. Moreover, multiple cervical lymphadenopathy, alopecia, and psoriasic exanthema on the planta were observed. There were no particular lesions of the vulva or inguinal lymphadenopathy. Serological examination showed the RPR test was×128, the TPHA test>2560, and the FTA-ABS test×1280. Since the Jarisch-Herxheimer reaction was induced after treatment with 1000mg/day of amoxicillin for 2 weeks, the patient was treated with 2000mg/day of erythromycin for 6 weeks. Oral lesions improved after 2 weeks of treatment, and the RPR test was×64 after 3 weeks of treatment. After 4 weeks of treatment, the oral lesions almost completely resolved.

A parasympathetic ganglion innervating the harderian gland and lacrimal gland of the musk shrew (Suncus murinus): fluorescent tracing and immunohistochemical studies.

A small ganglion, named the peri-trigeminal ganglion (PTG), was found in the ventromedial border of the rostral half of the trigeminal ganglion (TG) in the musk shrew (Suncus murinus). In frontal sections, the PTG was semicircular or elliptical in shape. Most of the neurons constituting this ganglion were round in shape and much smaller than those of the TG. The retrograde fluorescent tracer fluoro-gold was injected into various regions of the face in order to investigate innervation by the PTG neurons. When the tracer was injected subcutaneously around the external acoustic meatus and around the circumference of the orbit, a number of labeled neurons were seen not only in the TG but also in the PTG. After applying the tracer to the lacrimal gland (LG) and the harderian gland (HG), numerous labeled neurons were detected only in the PTG. A few labeled neurons were found in the PTG after injection into the palatoglossal arch. Immunohistochemically, most of the neurons constituting the PTG were positive for vasoactive intestinal polypeptide (VIP) antiserum. And a moderate number of somatostatin (SOM)-immunoreactive neurons and a small number of leucine-enkephalin (L-ENK)-immunoreactive neurons were detected. Numerous substance P-immunoreactive nerve fibers and varicosities were found in the PTG, and fewer L-ENK-, SOM- and VIP-immunoreactive fibers were observed. The present results suggest that the PTG is an autonomic ganglion that resembles in part the pterygopalatine ganglion in other species, and mainly innervates the HG and LG.

Use of buccal mucosal flaps for the correction of congenital soft palate defects in three dogs.

To present an alternative surgical technique for the repair of soft palate defects in dogs. Three Foxhound cross dogs. Bilateral buccal mucosal flaps, based at the palatoglossal arches, were raised. One flap was rotated so that the mucosal side created the floor of the nasopharynx. The second flap was rotated so that the mucosal side formed the roof of the oropharynx. The mucosa of the remnant of the soft palate and the pharyngeal walls was incised and the flaps sutured to these free mucosal edges. The caudal ends of the two flaps were sutured to each other. Complete closure of the soft palate defect was obtained in all three dogs. The dogs were monitored for between 1.5 and 3 years postoperatively, and no long-term problems were encountered. This surgical technique resulted in an excellent functional separation of the oropharynx and nasopharynx and allowed reconstruction of a large bilateral soft palate defect. By using the buccal mucosal flaps, as described in this report, a tension-free closure of large soft palate defects can be obtained, thereby eliminating a major cause of failure of this type of reconstructive surgery.

過長茎状突起症の４例

Clinical symptoms and radiographical findings in four cases of elongation of the styloid process are presented. The chief complaint in all four cases was a sore throat. Case 1: 60-year-old female. No obvious inflammation was found in the pharynx, but induration in the tonsillar fossa was detected by palpation. Case 2: 32-year-old male. Inflammation was slight and no process was detected by repeated palpation of the pharynx. Case 3: 72-year-old female. A slight projection was found on the palatoglossal arch, and a hard process was palpated in that region. Case 4: 35-year-old male. A hard process was palpated on the palatoglossal arch. Both orthopantomography and simple occipitofrontal radiography with open mouth were performed. Although orthopantomography can always image the Styloid process, findings from simple occipitofrontal radiography were sometimes in better agreement with clinical symptoms. Simple occipitofrontal radiography of the Styloid process sometimes showed an overlap of the upper jaw, but this problem can be solved by head rotation toward the healthy side during imaging. Case 2 underwent surgery and the symptoms improved.

Selective Attachment of β-Haemolytic Streptococci Group A to Oropharyngeal Epithelium in Health and Disease

Localization and semiquantification of β-haemolytic streptococci, Group A (GABHS), GABHS attachment and general bacterial attachment to epithelial cells (bacterial number and morphology) were studied during GABHS-positive acute tonsillitis and pharyngitis infections and among healthy GABHS carriers. Samples were collected from various areas of the oropharynx (palatine tonsils, posterior oropharyngeal wall, palatoglossal arch and buccal mucosa). During acute tonsillitis and pharyngitis, GABHS grew in samples obtained from the palatine tonsils and posterior oropharyngeal wall. The ratio of GABHS colonies to other aerobic colonies increased, and GABHS became attached to epithelial cells of both palatine tonsils and posterior oropharyngeal wall. In GABHS carriers, GABHS were found mainly on the palatine tonsils, but these microorganisms were not attached to the epithelium. Overall bacterial attachment to tonsillar and oropharyngeal epithelial cells increased during active tonsillitis and pharyngitis.

SEM study on the dorsal lingual surface of the common tree shrew, Tupaia glis.

The dorsal lingual surface of the common tree shrew was examined by SEM after treating it with HCl to remove the mucous substance. Filiform (FI), fungiform (FU) and circumvallate papillae (CI) were observed. The FI exhibited a small circular bulge surrounded by anterior and posterior filamentous processes. FU were scattered among the FI. There were 3 CI separating the anterior 4/5 from the posterior 1/5 of the tongue. In addition, a group of conical projections with caudal orientation was found anterior to the palatoglossal fold on each side of the tongue. Microridges were widely observed on the entire dorsal lingual surface, except on the free surface of FI processes.

舌根正中部における腺組織の組織学的検討 舌盲孔と後舌腺の形態について

The lingual root is an area where the thyroid gland develops and small salivary glands composed of both serous and mucous glands are distributed in the submucosa. In this paper the foramen cecum and mucous glands at the root of the tongue were histologically investigated in serial sagittal sections of the medial portion of the lingual root. The materials were obtained from 59 autopsied cases, excluding the cases with metabolic disease, brain tumor and neck tumor in whom the original disease might exert direct or indirect effects to the gland tissue. The frontal end was determined to be the line which connects the right and left palatoglossal arch junctions with the tongue, and the rear end the line of transition of the vallecula to the epiglottis. The specimen was cut in half along the median lingual sulcus and median glossoepiglottic fold. Each serial section of 4 microns in thickness was cut from the median plain to the lateral and stained with Hematoxylin-Eosin or Pas-Alcian blue at pH 2.5. The results of the study were summarized as follows. 1) The foramen cecum was histopathologically confirmed in 12 cases out of 59 (20%). The ratio of the detection did not show any difference between both sexes and in the groups of different age. 2) The mucous gland opening into the mucosal epithelium, which were located at the side of the lingual apex from the Ebner's gland or serous gland, were detected in 45 out of 59 (76%).(ABSTRACT TRUNCATED AT 250 WORDS)