Vestibular Groove Research Articles

Neurovascular anatomy of the developing human fetal penis and clitoris.

The human penile and clitoral development begins from a morphologically indifferent genital tubercle. Under the influence of androgen, the genital tubercle forms the penis by forming a tubular urethra within the penile shaft. Without the effect of the androgen, the genital tubercle differentiates into the clitoris, and a lack of formation of the urethra within the clitoris is observed. Even though there are similarities during the development of the glans penis and glans clitoris, the complex canalization occurring along the penile shaft eventually leads to a morphological difference between the penis and clitoris. Based on the morphological differences, the main goal of this study was to define the vascular and neuronal anatomy of the developing penis and clitoris between 8 and 12 weeks of gestation using laser scanning confocal microscopy. Our results demonstrated there is a co-expression of CD31, which is an endothelial cell marker, and PGP9.5, which is a neuronal marker in the penis where the fusion is actively occurring at the ventral shaft. We also identified a unique anatomical structure for the first time, the clitoral ridge, which is a fetal structure running along the clitoral shaft in the vestibular groove. Contrary to previous anatomical findings which indicate that the neurovascular distribution in the developing penis and clitoris is similar, in this study, laser scanning confocal microscopy enabled us to demonstrate finer differences in the neurovascular anatomy between the penis and clitoris.

Squamous Cell Carcinoma Arising From Odontogenic Cyst Epithelium or Oral Mucosa Epithelium After Marsupialization of Odontogenic Radicular Cyst in Posterior Mandible?

Squamous cell carcinomas (SCCs) are common malignant tumors in the oral and maxillofacial region. However, SCCs secondary to marsupialization of odontogenic radicular cysts are extremely rare. The authors report an unusual case of a 43-year-old male presented with dull pain in the right molar region of the mandible without numbness of lower lips, who had a long history of smoking, alcohol consumption, and betel nut chewing. Computerized tomography revealed a round well-defined unilocular radiolucent at the apex of lower right premolars, 2 nonvital teeth. The clinical diagnosis was the radicular cyst of the right mandible. The patient was initially treated with root canal therapy of the teeth followed by marsupialization with a mandibular vestibular groove incision. While the patient did not follow the instruction of irrigation of the cyst and had no regular follow-up. The reexamination of computerized tomography indicated a round well-defined unilocular radiolucent at the apex of lower right premolars and filled with a soft tissue without clear boundary with buccal muscles at 31 months follow-up. There were no masses or ulcer around the mandibular vestibular groove incision and the patient had no sign of numbness of lower lips. The clinical diagnosis was the radicular cyst of right mandible with infection. A curettage was performed. However, the pathologic diagnosis was well-differentiated SCC. An extended radical surgical resection including segmental resection of the right mandible was performed. The histopathology was well-differentiated SCC without the cyst epithelium and invasion of bone, which can be distinguished from primary intraosseous SCC. The case indicates that marsupialization performed in patients with a history of smoking, alcohol consumption, and betel nut chewing, has a risk of suffering from oral SCC.

Management of Ala Columella Disproportion in South East Asian Noses.

South East Asian noses have a characteristic ala and columella disproportion and mostly manifest as hanging ala. Simultaneous correction during rhinoplasty is recommended to achieve a good aesthetic result. Since hanging ala is a common feature, a classification system is presented as a guide for surgical management. The classification is based on the frontal view showing the alar rim connecting to the columella lobule area simulating the wings of a gull in gentle flight. A mild deformity has the gull's wing in the horizontal direction. A moderate deformity has the gull's wing in a slight inferior direction. A severe hanging deformity has the gull's wing in the inferior direction, ending below the columella lobule area, and this is mostly accompanied by retracted columella. There are various techniques for the surgical correction of hanging ala. The author has made a modification of the internal approach called "sail excision" using the groove within the lateral nasal vestibule as a landmark. The author terms this area as the vestibular groove. Sail excision involves removal of a triangular portion of tissue anterior to this vestibular groove. Another aesthetic deformity noticed in South East Asian noses is that the alar rim base is lower than the columellar base. In correcting hanging ala with involvement of the alar rim base, the sail excision is extended posteriorly following the vestibular groove as its guide to the amount to be excised. To enhance the overall aesthetic outcome, the acute columella labial angle seen in South East Asian noses has to be made fuller through surgery. This is accomplished using septal extension graft for tip projection, with preservation of the posterior angle of the caudal septum. Plumping grafts are used as filler material in the premaxillary area.

Two types of the tentacle structure of Entoprocta and the fine structure of the vestibular groove

The structure of the filtration apparatus of Entoprocta has been mainly investigated by light microscopy. The ultrastructure of the tentacles has been investigated in detail in only one species, Loxosomella elegans, and the ultrastructure of the cells of the vestibular groove has not been described at all. In this paper, the structures of the filtration apparatuses of two species are studied: the colonial species Pedicellina cernua (Pallas, 1774) (Entoprocta, Coloniales) and the solitary species Loxosomella nordgaardi Ryland 1961 (Entoprocta, Solitaria). The ultrastructure of the epidermis of the tentacles, as well as sensitive organs, muscles and nerve fibers, is described in detail. A comparison of the structures of tentacles of different species facilitated distinguishing two possible variants of organization of the tentacle—one with the frontal groove and one without the frontal groove, depending on the size of the calyx and tentacles. Some differences are also noted in the ultrastructure of the abfrontal cells of the tentacles in colonial and solitary species, which possibly determine the differences in the process of contraction of the tentacles. In some cases, the tentacles only bend without changing their length, and in other cases, they also shorten. The ciliary vestibular groove lies at the base of the tentacles. It was noted that the ciliary rows of the tentacles continue as the ciliary cells of the rims and walls of the groove. The ultrastructure of the cells of the rim of the groove is similar to the ultrastructure of the lateral cells of the tentacles. The cells of the walls of the groove are similar to the frontal cells of the tentacles. The cells of the bottom of the groove differ from all types of cells of the tentacles.

Application of a Lateral Pedicled Cranial Bone Flap for the Treatment of Secondary Zygomaticomaxillary Defects.

This study aimed to evaluate the effect of laterally-based pedicled cranial bone flap (LBPCBF) for the repair of secondary zygomaticomaxillary defects. Between December 2014 and December 2016, 6 patients with unilateral zygomaticomaxillary defects were selected; of these, 5 had trauma, and 1 was exposed to titanium mesh in the infraorbital area due to radiotherapy following total maxillectomy for right maxillary squamous cell carcinoma. Preoperatively, 3 patients suffered from an intraoral vestibular groove fistula, 2 suffered from an extraoral fistula, and 1 from local exposure of titanium mesh. Surgical treatment was implemented in all 6 patients, of which, the 5 trauma patients underwent debridement, reduction, and fixation of periorbital fracture, followed by repair of the defects in the infraorbital margin, anterior wall of maxillary sinus, and zygomatic body with LBPCBF, and then, reconstruction of the orbital floor with titanium mesh. The other patient with exposed titanium mesh underwent repair of defects in the infraorbital margin and anterior wall of the maxillary sinus with LBPCBF after titanium mesh trimming. Postoperative review at 6 months revealed disappearance of intraoral fistula, wound healing, and improvement of facial deformity in all 6 patients, of which 2 patients demonstrated postoperative ectropion. The application of LBPCBF can simultaneously repair bone defects in the infraorbital margin, anterior wall of maxillary sinus, and zygomatic body, as well as, supplement the soft tissue, thereby indicating a satisfactory treatment effect.

Development of the human penis and clitoris

The human penis and clitoris develop from the ambisexual genital tubercle. To compare and contrast the development of human penis and clitoris, we used macroscopic photography, optical projection tomography, light sheet microscopy, scanning electron microscopy, histology and immunohistochemistry. The human genital tubercle differentiates into a penis under the influence of androgens forming a tubular urethra that develops by canalization of the urethral plate to form a wide diamond-shaped urethral groove (opening zipper) whose edges (urethral folds) fuse in the midline (closing zipper). In contrast, in females, without the influence of androgens, the vestibular plate (homologue of the urethral plate) undergoes canalization to form a wide vestibular groove whose edges (vestibular folds) remain unfused, ultimately forming the labia minora defining the vaginal vestibule. The neurovascular anatomy is similar in both the developing human penis and clitoris and is the key to successful surgical reconstructions.

Canalization of the Vestibular Plate in the Absence of Urethral Fusion Characterizes Development of the Human Clitoris: The Single Zipper Hypothesis

We characterized the early gestation development of the female external genitalia using optical projection tomography to visualize anatomical structures at high resolution. First and early second trimester human female fetal external genitalia were collected with consent after voluntary termination. Specimens labeled with anti-E-Cadherin antibody underwent analysis with optical projection tomography. Histological sections were immunostained for androgen receptor, 5α-reductase, Ki67 for proliferation and Caspase 3 for apoptosis. Three-dimensional reconstructions demonstrated proximal to distal canalization of the epithelial vestibular plate and formation of a vestibular groove, which remained open. Ki67 was observed throughout with greatest density in the dorsal vestibular plate at the level of the opening groove. Staining for Caspase 3 was minimal in all sections. Androgen receptor staining was seen throughout the mesenchyme and in the apical epithelium of the dorsal vestibular groove. Throughout the epithelium and epidermis 5α-reductase staining was observed. Early development of the external genitalia in the female is analogous to that in the male, demonstrating a similar opening zipper driving canalization of the vestibular plate with localized epithelial proliferation in theabsence of significant apoptosis. Thus we hypothesize that the mechanism underlying the opening zipper must be androgen independent and the absence of androgen driven urethral fusion characterizes the normal development of the human clitoris.

Novel method of fabricating individual trays for maxillectomy patients by computer-aided design and rapid prototyping.

Making impressions for maxillectomy patients is an essential but difficult task. This study developed a novel method to fabricate individual trays by computer-aided design (CAD) and rapid prototyping (RP) to simplify the process and enhance patient safety. Five unilateral maxillectomy patients were recruited for this study. For each patient, a computed tomography (CT) scan was taken. Based on the 3D surface reconstruction of the target area, an individual tray was manufactured by CAD/RP. With a conventional custom tray as control, two final impressions were made using the different types of tray for each patient. The trays were sectioned, and in each section the thickness of the material was measured at six evenly distributed points. Descriptive statistics and paired t-test were used to examine the difference of the impression thickness. SAS 9.3 was applied in the statistical analysis. Afterwards, all casts were then optically 3D scanned and compared digitally to evaluate the feasibility of this method. Impressions of all five maxillectomy patients were successfully made with individual trays fabricated by CAD/RP and traditional trays. The descriptive statistics of impression thickness measurement showed slightly more uneven results in the traditional trays, but no statistical significance was shown. A 3D digital comparison showed acceptable discrepancies within 1 mm in the majority of cast areas. The largest difference of 3 mm was observed in the buccal wall of the defective areas. Moderate deviations of 1 to 2 mm were detected in the buccal and labial vestibular groove areas. This study confirmed the feasibility of a novel method of fabricating individual trays by CAD/RP. Impressions made by individual trays manufactured using CAD/RP had a uniform thickness, with an acceptable level of accuracy compared to those made through conventional processes.

Dental implants and free fibula flap: 23 patients

Mandibular reconstruction with a microvascular free fibula flap (MFF) is an elegant solution to restore the anatomic arch, oral functions, and facial esthetics. But the thin cutaneous tissue, the thickness of subcutaneous tissues, the absence of a pelvilingual and vestibular groove, and the fragility of soft tissues complicate dental prosthetic stabilization. Implants may restore prosthetic functionality. A lot has been published on osteointegration with a MFF, but few studies have been aimed at the prosthetic aspect, final goal of any oral reconstruction. The aim of this retrospective study was to present the results of oral reconstruction with implant supported prostheses after mandibular reconstruction with a MFF. Twenty-three patients underwent mandibular reconstruction: 17 men and six women with a mean age of 46 years (17-66). Fourteen patients (60.8%) underwent radiotherapy before reconstruction. Mandibular osteoradionecrosis was the indication for reconstruction in seven patients. Each patient was assessed by dentascan. Implants were placed under general anesthesia. Postoperative clinical and radiographic controls were made regularly. Transmucous abutments were placed after six postoperative months and the prosthetic phase was initiated one month later. The criteria for implant and prosthetic success were assessed. Seventy-five implants were placed, on average 3.2 per patient, with an 80% success rate. Three implants (4%) were not used for prosthesis placement. Ten permanent prostheses and 13 removable prostheses were placed. The mean delay before implant loading was 7.6 months (6-10) and the mean follow-up was 27.5 months (1-71). Occlusion was considered as "satisfactory" for 69.6% of patients. For 57% of patients, the quality of surrounding soft tissues was considered as "satisfactory". For 74% of patients, oral rehabilitation was "satisfactory". The implant supported prosthesis after MFF mandibular reconstruction, on an irradiated site or not, gives satisfactory results despite the thickness and mobility of soft tissues, and despite scar contracture and the absence of keratinization. Implant placement must be performed after a prosthetic planning. Using radiosurgical guides, despite their cost and difficult adaptation, would certainly improve the technique greatly.

Microsurgical Reconstruction of the Jaw With Fibular Grafts and Implants

Reconstructive treatments for jaw defects are complex procedures that can combine multiple techniques including fibula free flap (FFF) grafting. The purpose of this retrospective study was to document and share our experience on mandibular and maxillar reconstruction with FFF followed by secondary dental rehabilitation using implant insertion.We reviewed 198 patients treated by FFF grafting for mandibular and/or maxillary defects in our department during the past 11 years (1996-2007). A selection of 30 patients (18 males and 12 females, mean age of 46 y) with adequate criteria (hygiene, motivation, and prognosis) received secondary placement of osseointegrated implants. The implant success was clinically and radiographically evaluated.A total of 105 osseointegrated implants were placed in the grafted fibulas 5 months to 3 years after the reconstruction surgery. Only 4 implants were lost because of peri-implantitis (3 patients) and fibular fracture (1 patient); this corresponds to a 96.2% implant success rate.During the mean follow-up of 76 months, patient's satisfaction and functional and aesthetic results were evaluated. Radiologic findings indicated a low crest resorption around the implants despite an unfavorable crown-to-root ratio.The main difficulties in the reconstructions were lack of FFF height, absence of a vestibular groove, limitation of mouth opening, skin paddle thickness, and the reconstruction of surrounding tissues including the lip. Our management strategy is discussed.Prosthetic choice is fundamental to achieving patient-specific solutions. The prostheses used included sealed or screwed bridge, resin-bonded bridge, tooled bar, implant-borne denture, or implant-stabilized dentures. Dental implants may be used even in situations involving an unfavorable crown-to-root ratio and implant position by using milled bar and overdenture. The FFF provides a consistent bone graft that allows a reliable and predictable restoration with dental implants, leading to a satisfactory functional and aesthetic restoration.

Blending of the eyelid–cheek junction and removal of protruding fat: an intraoral approach to blepharoplasty of the lower eyelid

Blepharoplasty is one of the most common aesthetic procedures done today. The protruding fat and lid–cheek junction are the most conspicuous signs of aging that need attention. During zygomatic reduction by an intraoral approach we found occasionally that the orbital fat can be exposed through the perforated periosteum at the inferior obital rim. We therefore developed a new blepharoplasty procedure using an oral approach. Seventeen patients aged from 26 to 38 years, of whom six had had a previous unsuccessful blepharoplasty and one had a history of injury to the lower lid, were studied. The operation was done under an infraorbital nerve block and local anaesthesia through an intraoral incision at the upper vestibular groove. The periosteum was raised on the surface of the maxilla to the infraorbital rim, and the infraorbital nerve preserved. The periosteum and the orbital septum were incised along the whole length of the infraorbital rim. The fat that was exposed through the incision was either removed or preserved and fixed to the outer soft tissue with sutures. Cosmetic results were good and the oral incision healed without infection. Six patients developed numbness in the infraorbital region, five of whom recovered within 3 months; the other recovered by 6 months postoperatively.

Implants dentaires et lambeau de fibula microanastomosé : 23 patients

Mandibular reconstruction with a microvascular free fibula flap (MFF) is an elegant solution to restore the anatomic arch, oral functions and facial esthetics. But the thin cutaneous tissue, the thickness of subcutaneous tissues, the absence of a pelvilingual and vestibular groove, and the fragility of soft tissues complicated dental prosthetic retention. Implants may restore prosthetic functionality. There is considerable publication on osteo-integration with a microvascular free fibula flap, but few studies were aimed at the prosthetic aspect, finality of any oral reconstruction. The aim of this retrospective study was to present the results of oral reconstruction with implant supported prostheses after mandibular reconstruction with a microvascular free fibula flap.Twenty-three patients underwent mandibular reconstruction: 17 men and six women with a mean age of 46 years (17-66). Fourteen patients (60.8%) underwent radiotherapy before reconstruction. Mandibular osteoradionecrosis was the indication for reconstruction in seven patients. Each patient was assessed by dentascan. Implants were placed under general anesthesia. Postoperative clinical and radiographic controls were made regularly. Transmucous abutments were placed after six postoperative months and the prosthetic phase was initiated one month later. The criteria for implant and prosthetic success were assessed.Seventy-five implants were placed, on average 3.2 per patient, with an 80% success rate. Three implants (4%) were not used for prosthesis. Ten permanent prostheses and 13 removable prostheses were placed. The mean delay before implant loading was 7.6 months (6-10) and the mean follow-up was 27.5 months (1-71). The occlusion was considered as "satisfactory" for 69.6% of patients. For 57% of patients, the quality of surrounding soft tissues was considered as "satisfactory". For 74% of patients oral reconstruction was "satisfactory".The implant supported prosthesis after MFF mandibular reconstruction, on an irradiated site or not, gives satisfactory results despite the thickness and mobility of soft tissues, and despite scar contracture and the absence of keratinization. Implant placement must be performed after a prosthetic planning. Using radio-surgical guides, despite their cost and difficult adaptation, would certainly bring important improvement to the technique.

The Ciliary Feeding Mechanism of the Ento-proct Polyzoa, and a comparison with that of the Ectoproct Polyzoa

An account is given of the ciliary feeding mechanism of the Entoproct Polyzoa, and of the structure of the lophophore and tentacles. The long lateral cilia cause a current of water to pass inwards between the tentacles, and throw particles on to the short frontal cilia of the inner surface, which carry them to the vestibular groove leading to the mouth. The behaviour of the lateral cilia of the tentacles of L. crassicauda is described, and it is suggested that they are under the nervous control of the animal. A résumé of Borg's work on the ciliary feeding mechanism of the Ectoprocta is given, a note on Flustrella hispida being added. It is pointed out that the method of feeding in this group differs widely from that of the Entoprocta.