Somatosensory innervation of healthy human oral tissues.

The oral somatosensory system relays essential information about mechanical stimuli to enable oral functions such as feeding and speech. The neurochemical and anatomical diversity of sensory neurons across oral cavity sites have not been systematically compared. To address this gap, we analyzed healthy human tongue and hard-palate innervation. Biopsies were collected from 12 volunteers and underwent fluorescent immunohistochemistry (≥2 specimens per marker/structure). Afferents were analyzed for markers of neurons (ßIII tubulin), myelinated afferents (neurofilament heavy, NFH), and Merkel cells and taste cells (keratin 20, K20). Hard-palate innervation included Meissner corpuscles, glomerular endings, Merkel cell-neurite complexes, and free nerve endings. The organization of these somatosensory endings is reminiscent of fingertips, suggesting that the hard palate is equipped with a rich repertoire of sensory neurons for pressure sensing and spatial localization of mechanical inputs, which are essential for speech production and feeding. Likewise, the tongue is innervated by afferents that impart it with exquisite acuity and detection of moving stimuli that support flavor construction and speech. Filiform papillae contained end bulbs of Krause, as well as endings that have not been previously reported, including subepithelial neuronal densities, and NFH+ neurons innervating basal epithelia. Fungiform papillae had Meissner corpuscles and densities of NFH+ intraepithelial neurons surrounding taste buds. The differing compositions of sensory endings within filiform and fungiform papillae suggest that these structures have distinct roles in mechanosensation. Collectively, this study has identified previously undescribed neuronal endings in human oral tissues and provides an anatomical framework for understanding oral mechanosensory functions.

Revisiting major anatomical risk factors of maxillary sinus lift and soft tissue graft harvesting for dental implant surgeons.

The anatomical variations of the maxillary sinus septa, greater palatine artery, and posterior superior alveolar arteries might cause unexpected complications when they are damaged. Dentists who know these structures well might hope to learn more practical knowledge to avoid and assess injury preoperatively. Therefore, this review paper aimed to review the reported anatomy and variations of the maxillary sinus septa, greater palatine artery/nerve, and posterior superior alveolar artery, and to discuss what has to be assessed preoperatively to avoid iatrogenic injury. To assess the risk of injury of surgically significant anatomical structures in the maxillary sinus and hard palate, the operator should have preoperative three-dimensional images in their mind based on anatomical knowledge and palpation. Additionally, knowledge of the average measurement results from previous studies is important.

Supernumerary incisive canals in a cadaver: a rare anatomical variation.

We present a rare anatomical variation in which an additional incisive canal was observed during the routine dissection of the palatal region in a cadaver. The diameter of the incisive and additional incisive canals measured 4.59 mm and 0.91 mm, respectively. Even though this variation is rare, oral surgeons should be aware of such anatomical variations for a better understanding.

Perineural Invasion and Perineural Tumor Spread in Head and Neck Cancer.

Perineural invasion (PNI), the neoplastic invasion of nerves, is a common pathologic finding in head and neck cancer that is associated with poor clinical outcomes. PNI is a histologic finding of tumor cell infiltration and is distinct from perineural tumor spread (PNTS), which is macroscopic tumor involvement along a nerve extending from the primary tumor that is by definition more advanced, being radiologically or clinically apparent. Despite widespread acknowledgment of the prognostic significance of PNI and PNTS, the mechanisms underlying its pathogenesis remain largely unknown, and specific therapies targeting nerve invasion are lacking. The use of radiation therapy for PNI and PNTS can improve local control and reduce devastating failures at the skull base. However, the optimal volumes to be delineated with respect to targeting cranial nerve pathways are not well defined, and radiation can carry risks of major toxicity secondary to the location of adjacent critical structures. Here we examine the pathogenesis of these phenomena, analyze the role of radiation in PNI and PNTS, and propose guidelines for radiation treatment design based on the best available evidence and the authors' collective experience to advance understanding and therapy of this ominous cancer phenotype.

Morphological observation and CBCT of the bony canal structure of the groove and the location of blood vessels and nerves in the palatine of elderly human cadavers.

PURPOSE: The greater and lesser palatine nerves and vessels supply the hard and soft palates, and the roots of these vessels and nerves run through a bony structure. However, the arrangement of blood vessels in the maxilla requires attention during clinical treatments, but detailed morphological information about changes in the greater and lesser palatine arteries and nerves during aging is unavailable. We therefore need detailed investigations of the morphology of the donor cadaver palatine using cone-beam computed tomography (CBCT) and macroscopic observations. METHODS: We investigated 72 donor cadavers using macroscopic segmentation and CBCT. The results' analysis examined differences in skull measurement parameters and differences between dentate and edentulous cases. RESULTS: The greater palatine artery and nerve showed different macroscopic arrangements in dentate and edentulous cadavers. We also classified three types of bony structures of the nerve and vessel roots in the molar regions of the palatine using CBCT images: the shallow groove, deep groove, and flat groove. The deep groove is the deepest of the three and is remarkable in edentulous elderly cadavers. CONCLUSION: This study of macroscopic and CBCT data provides information useful for planning dental implant surgeries and autogenous bone harvesting.

A Hypothesis and Pilot Study of Age-Related Sensory Innervation of the Hard Palate: Sensory Disorder After Nasopalatine Nerve Division.

BACKGROUND The nasopalatine nerve may be injured during extraction of teeth embedded in the anterior hard palate. The neural recovery process and its impact on sensation in the anterior hard palatal region are controversial. In our clinical practice, we noticed a distinct recovery process in children compared with adolescents or adults after surgery. We hypothesized that the sensory innervations of the anterior palate might shift during later childhood and pre-adolescence, which is due to the development of the nasopalatine nerve along with the maxillary growth and permanent teeth eruption. MATERIAL AND METHODS Forty patients (20 females and 20 males, mean age 11.8±2.2) with impacted supernumerary teeth in anterior palatine area were included into our study, and were divided into 3 groups according to their age. A 24-week follow-up was conducted and the sensation in the anterior hard palate region was examined at every check point. All the data were collected and analyzed by Kaplan-Meier analysis. RESULTS Fourteen children did not complain of any numbness immediately after anesthetization, and other children with sensory disorders had shorter healing periods compared to adolescent/adult patients. CONCLUSIONS The results indicated that the dominant nerve of the anterior hard palate region was dramatically changed from the greater palatine nerve to the nasopalatine nerve, which is important in deciding when to operate and in selection of anesthesia method.

Computerized analysis of the greater palatine foramen to gain the palatine neurovascular bundle during palatal surgery.

OBJECTIVE: Investigation of the computerized dimensional anatomic location of the greater palatine foramen (GPF) and lesser palatine foramens (LPF) is important indicating site to collect palatal donor tissue, reconstructioning the orofacial area of the oncology patient and applying the greater palatine nerve block anesthesia. The aim of this study is to determine a patient-friendly landmark and to specify the precise location of the GPF in order to standardise certain anatomical marks of safe neurovascular bundle. MATERIALS AND METHODS: 120 bony palates were examined to detect the position of the GPF and the LPF related to adjacent anatomical landmarks using a computer software program. The GPF was assessed regarding the position, the diameter and the distances between each foramen and the midline maxillary suture (MMS), the inner border of alveolar ridge (AR), posterior palatal border (PBB), and incisive foramen (IF). RESULTS: The GPF was identified as single in 81 %, double in 16 %, triple in 2 % and absent in 2 % of the specimens. The mean distances between the GPF and the MSS, the GPF and the AR, the GPF and the PPB, the GPF and the IF were 16, 4, 4, and 40 mm, respectively. In majority of the cases, the GPF was seen between the distal surfaces of the third maxillary molar (78 %). Single LPF was observed in 53.45 % of the skulls, two LPF were observed in 31 % of the skulls bilaterally and five LPF were rare in 2.1 % of the specimens. The LPF was most commonly at the junction of the palatine bone and the inner lamella of the pterygoid plate (71.9 %). CONCLUSIONS: This study made possible to investigate the variability of the GPF and the feasibility of the greater palatine neurovascular bundle, and to calculate the lengths of some parameters with the help of certain software. To collect the donor tissue of the neurovascular greater palatine network, each distance among the AR-GPF-PPB were equal to 4 mm. To estimate the possible length of the graft, the incision was made along the third and the second molar to the IF as 4 cm. The data we obtained within this study have been presented to help the surgeons avoid unexpected hemorrhage during the palatinal procedures such as posttraumatic dental reconstruction, maxillofacial tumor resections, palatal micro-implants, and dentofacial orthopedic surgery.

Treatment of a subtype of trigeminal neuralgia with descending palatine neurotomy in the pterygopalatine fossa via the greater palatine foramen-pterygopalatine canal approach.

PURPOSE: To discuss an effective surgical treatment of a subtype of trigeminal neuralgia with descending palatine neuralgia of the maxillary division. METHOD: Nine patients, who suffered from trigeminal neuralgia with descending palatine neuralgia of the maxillary division, received neurotomy and avulsion of the descending palatine nerve in the pterygopalatine fossa via the greater palatine foramen-pterygopalatine canal approach. Seven of the patients had a recurrence of descending palatine neuralgia after they received treatment of maxillary neuralgia with neurotomy and avulsion of the infraorbital nerve; two patients were diagnosed with descending palatine neuralgia of the maxillary division in our department. Postoperative follow-up was conducted. RESULTS: Pain in the palate disappeared; all patients felt numb and paresthetic in the area innervated by the trigeminal nerve, with no pain. During the 3-36 months of follow-up, no recurrence occurred. CONCLUSIONS: Descending palatine neurotomy in the pterygopalatine fossa via the greater palatine foramen-pterygopalatine canal approach is a simple, safe and effective way to treat a subtype of trigeminal neuralgia--descending palatine neuralgia.

Topographical relationship of the greater palatine artery and the palatal spine. Significance for periodontal surgery.

AIM: The aims of this study were to (1) identify the branching pattern and course of the greater palatine artery (GPA), (2) carry out a morphological analysis of the palatal bony prominence that divides the medial and lateral grooves and (3) characterize the topographical relationships between these two structures. METHODS: Thirty-six hemimaxillae were studied with the aid of a surgical microscope to elucidate the GPA. A further 25 dry skulls were examined to establish the morphology of the palatal spine. RESULTS: The most common GPA branching pattern was type I (41.7%, 15 sides), which gave off the medial and canine branches after the bony prominence. The distances from the CEJ to the lateral branch of the GPA were 9.04 ± 2.93 mm (canine), 11.12 ± 1.89 mm (first premolar), 13.51 ± 2.08 mm (second premolar), 13.76 ± 2.86 mm (first molar) and 13.91 ± 2.20 mm (second molar). The palatal spine was frequently observed as the bony prominence (66.3%, 57 sides), and was located at 6.49 ± 1.76 mm from the greater palatine foramen, with a length of 10.42 ± 2.45 mm. There was no a correlation between the bony prominence shape and the GPA branching pattern. CONCLUSIONS: These results could provide the reference data regarding the topography of the GPA for periodontal surgery.

A study of the anatomical variations in the position of the greater palatine foramen in adult human skulls and its clinical significance / Variaciones anatómicas en la posición del foramen palatino mayor en cráneos humanos adultos y su significación clínica

Pain is a common distressing symptom in dental practice. Depending upon the cases, different techniques are used to relieve pain. One of these is peripheral trigeminal nerve block. Peripheral trigeminal nerve block anaesthesia has proved to be an effective and convenient way to anaesthetise large regions of oral and maxillofacial complex. This block can be intraoral or extra oral. The intraoral route is through the greater palatine foramen in which the dental surgeons enter into the pterygopalatine fossa, where the maxillary nerve is situated. The morphological variations in the position of greater palatine foramen may be of clinical importance in the administration of local anaesthesia and in palatal surgery. In the present study, the distance of greater palatine foramen from the median palatine suture, and from the posterior border of hard palate have been noted, and the position of greater palatine foramen relative to the maxillary molars, as well as the direction of the foramen have been examined.

El dolor es un síntoma común y preocupante en la práctica dental. Dependiendo de los casos, diferentes técnicas se utilizan para aliviar el dolor. Una de ellas es el bloqueo periférico del nervio trigémino. Esta, ha demostrado ser una forma eficaz y conveniente para anestesiar grandes regiones del complejo oral y maxilofacial. Este bloqueo puede ser intraoral o extraoral. La vía intraoral es a través del foramen palatino mayor en la cual se ingresa en la fosa pterigopalatina, donde se encuentra el nervio maxilar. Las variaciones morfológicas en la posición del foramen palatino mayor puede ser de importancia clínica en la administración de anestesia local y en la cirugía del paladar. En el presente estudio, se examinó la distancia del foramen palatino mayor desde la sutura palatina mediana y el margen posterior del paladar duro, y su posición relativa a los molares superiores, así como la dirección del foramen palatino mayor.

Greater palatine foramen--key to successful hemimaxillary anaesthesia: a morphometric study and report of a rare aberration.

INTRODUCTION: Accurate localisation of the greater palatine foramen (GPF) is imperative while negotiating the greater palatine canal for blocking the maxillary nerve within the pterygopalatine fossa. The aim of this study was to define the position of the foramen relative to readily identifiable intraoral reference points in order to help clinicians judge the position of the GPF in a consistently reliable manner. METHODS: The GPF was studied in 100 dried, adult, unsexed skulls from the state of Maharashtra in western India. Measurements were made using a vernier caliper. RESULTS: The mean distances of the GPF from the midline maxillary suture, incisive fossa, posterior palatal border and pterygoid hamulus were 14.49 mm, 35.50 mm, 3.40 mm and 11.78 mm, respectively. The foramen was opposite the third maxillary molar in 73.38% of skulls, and the direction in which the foramen opened into the oral cavity was found to be most frequently anteromedial (49.49%). In one skull, the greater and lesser palatine foramina were bilaterally absent. Except for the invariably present incisive canals, there were no accessory palatal foramina, which might have permitted passage of the greater palatine neurovascular bundle in lieu of the absent GPF. To the best of our knowledge, this is the first study of such a non-syndromic presentation. CONCLUSION: The GPF is most frequently palatal to the third maxillary molar. For an edentulous patient, the foramen may be located 14-15 mm from the mid-palatal raphe or about 12 mm anterior to the palpable pterygoid hamulus.

Attempted validation of a method to locate entry and exit foramens of the branches of the trigeminal nerve; benefits for an original cephalometric analysis technique.

INTRODUCTION: Trigeminal analysis focuses on the skeletal entrance and exit orifices of the sensitive fibers of the trigeminal nerve. The aim of this study was to validate the techniques used to locate these landmarks as described by the creator of trigeminal analysis of the face. MATERIALS AND METHOD: This descriptive study was performed on a dry human skull. Two tin balls forming markers R1 and R2 were fixed at random on the skull in a median sagittal position. Two headfilms of the skull were made. The first showed tin balls fixed at the entrance and exit foramens of the sensitive fibers of the trigeminal nerve. The second showed the foramens without the tin balls. The position of the reference point corresponding to the entrance and exit points of the trigeminal fibers was entered on a tracing made from the headfilm (without the balls on the foramens) by 16 operators using an ad hoc guide supplied by Crocquet. A comparison was made between the points as positioned by these operators and the true points as revealed by the X-rays of the balls on the first image (Gold Standard) by calculating the difference between their coordinates on an axis connecting R1 et R2 (X-axis) and the line perpendicular to it passing through R2 (Y-axis). Trigeminal cephalometric analysis was then performed on each of the tracings. The angles and linear values were compared. The validity of the positioning of the points and of the values provided by the analysis was demonstrated by the existence of a difference of less than 2units (mm or degrees). RESULTS: No difference in the means between the trigeminal points found by the operators and the Gold Standard points represented by the X-rays of the balls placed on the foramens exceeded 2mm in absolute value on the Y-axis. On the X-axis, the differences greater than 2mm in absolute value related to: the supra-orbital notch (ESO) and the foramen ovale (FO) (2.12 and 8.19mm, respectively). The angles (ESO-TGR-TO) and (TGR-ESO-TSO) were the only ones to display differences exceeding 2° in absolute value between the two images. CONCLUSION: The detection method advanced by Crocquet for the positioning of the eight points of reference used for analyzing the entrance and exit foramens of the trigeminal nerve is valid apart from the TO and ESO points. Consequently, the validity of the angle measurements involving these points is affected. Further research is required to confirm these findings. If necessary, new recommendations should be devised in order to improve the localization of the TO and ESO cephalometric points.

Neurovascular anatomical variations in the anterior palate observed on CBCT images.

OBJECTIVE: This study aimed to assess the presence of additional foramina and canals in the anterior palate region, through cone beam computed tomography (CBCT) images, describing their location, direction, and diameter. MATERIALS & METHODS: CBCT exams of 178 subjects displaying the anterior maxilla were included and the following parameters were registered: gender; age group; presence of additional foramina in the anterior palate (AFP) with at least 1 mm in diameter; location and diameter of AFP; and direction of bony canals associated with AFP. RESULTS: Twenty-eight patients (15.7%) presented AFP and in total 34 additional foramina were registered. No statistical differences between patients with or without AFP were found for gender or age. The average diameter of AFP was 1.4 mm (range from 1 to 1.9 mm). Their location was variable, with most of the cases occurring in the alveolar process near the incisors or canines (n = 27). In 18 cases, AFP was associated with bony canals with upward or oblique direction toward the anterior nasal cavity floor. In 14 cases, the canal presented as a direct extension of the canalis sinuosus, in an upward direction laterally to the nasal cavity aperture. In two cases, the canal was observed adjacent to the incisive and joined the nasopalatine canal superiorly. DISCUSSION: CBCT images have a crucial role in the recognition of anatomical variations by allowing detailed tridimensional evaluations. Additional foramina and canals in the anterior region of the upper jaw are relatively frequent. Practitioners should be aware and trained to identify these variations. CONCLUSIONS: Over 15% of the population studied had additional foramina in the anterior palate, between 1 mm and 1.9 mm wide, with variable locations. In most cases the canals associated with these foramina either presented as a direct extension of the canalis sinuosus, or coursed towards the nasal cavity floor.

The accessory posterolateral nerve: an immunohistological analysis.

BACKGROUND: Recent endoscopic dissection studies have redefined the postganglionic pterygopalatine autonomic pathways suggesting that neurovascular rami, termed "accessory posterolateral nerves," project directly through the palatine bone to innervate the posterolateral nasal mucosa rather than traveling with trigeminal arborizations. The goal of this study was to characterize these accessory posterolateral nerves by immunohistochemistry to determine their morphology and composition. METHODS: This is an Institutional Review Board approved study in seven patients in whom the presence of accessory posterolateral nerves were surgically identified exiting the perpendicular plate of the palatine bone and sampled. The presence of neural tissue was confirmed by hematoxylin and eosin and S-100 protein staining. Nerves were then stained with anti-human choline acetyl-transferase (ChAT; 1:100) and anti-human dopamine beta-hydroxylase (DBH; 1:100) followed by a fluorescein isothiocyanate-labeled secondary antibody to test for the presence of peripheral parasympathetic and sympathetic fibers, respectively. Human cadaveric sensory nerves were used as a negative control. RESULTS: All seven samples contained neural elements. Two specimens were also associated with arteries. All nerves were comprised of a single fascicle containing an approximately equal distribution of ChAT(+) and DBH(+) fibers. CONCLUSION: This histological study supports prior descriptions defining a newly recognized neural pathway for innervation of the nasal mucosa. Our data confirm that these accessory posterolateral nerves project directly through the perpendicular plate of the palatine bone and are composed of autonomic fibers. Recognition of this pathway may be exploited in the treatment of sinonasal disease resulting from autonomic dysregulation.

Three-dimensional analysis of maxillary anatomic landmarks for greater palatine nerve block anesthesia.

Greater palatine nerve block anesthesia (GPNBA) is a local anesthetic procedure used for maxillary and nasal treatment. Investigation of the three-dimensional anatomic location of the greater palatine foramen (GPF) is important for successful local anesthesia. The study aim was to provide standards for anatomic structures in the oral cavity that can be easily referred to in GPNBA. Maxillary computed tomography data were obtained from patients between 8 and 16 years of age whose maxillary incisors and first molars had already erupted (the growth group, n = 103); changes in the maxilla were observed over time in this group. Reference values for GPNBA in adults were measured in 107 patients older than 18 years. Maxillary computed tomography images were reconstructed three-dimensionally. Regression analysis demonstrates that all maxillary measurements in the growth group except for the distance from the posterior nasal spine to the GPF in the coronal plane correlated significantly with age. In adults, the mean perpendicular distance from the interdental alveolar bone between the left and right central incisors (1alvB) to the GPF in the coronal plane was 46.16 mm, and the mean distance from 1alvB to the GPF was 51.05 mm. The mean distance from the maxillary central incisor to the GPF was 57.58 mm. The mean angle between the line from the maxillary central incisor to each GPF and the sagittal plane was 16.49 degrees. The mean perpendicular distance from the anterior nasal spine to the GPF in the coronal plane was 43.49 mm, whereas the mean perpendicular distance from the GPF to the bone plane was 12.67 mm, and the mean perpendicular distance from the GPF to the occlusal plane was 22.13 mm. These measurements can be used to find the height of the GPF. In adults, the measured perpendicular distance from the incisive foramen to the GPF in the coronal plane was 32.04 mm, and the perpendicular distance from the median of the line that connects both of the contact points between the maxillary tuberosity and the pterygoid plate to the GPF in the coronal plane was 5.23 mm. Three-dimensional reference values relative to the anatomic structures in the oral cavity may increase the success rate of GPNBA and reduce complications. Although the maxillary growth pattern was analyzed, a limitation of this study is that maxillary anatomic measurements were not analyzed with regard to race or ethnicity.

Clinical measurements of hard palate and implications for subepithelial connective tissue grafts with suggestions for palatal nomenclature.

PURPOSE: The objectives of the present study were to 1) identify a reliable measuring technique for a palatal graft, 2) observe the patterns of the neurovascular bundle, and 3) identify the morphology of the hard palate. Subepithelial connective tissue grafts are performed at an increasing rate to improve esthetics and oral health. Palatal graft techniques began in 1963, and today the subepithelial connective tissue graft is the most widely accepted technique. The greater palatine nerve and artery are critical neurovascular structures to identify. Their pattern and palate morphology are not well defined. MATERIALS AND METHODS: Anatomy texts, atlases, and specialty texts were analyzed. We dissected 17 palates (17 left and right halves) from embalmed human cadavers, implementing a measuring technique to locate the most coronal structure of the greater palatine artery and greater palatine nerve bundle, observing the patterns and palatal morphology. Electronic digital calipers and a periodontal probe were used for data collection. RESULTS: The dissection results revealed a reliable measuring technique, a common pattern of the bundle, and osseous palatal landmarks not clearly defined in contemporary texts. The dissections also demonstrated a medial and lateral groove, along with a crest in the palatine process of the maxillary bone. The greater palatine artery traversed the lateral groove, and the greater palatine nerve traversed the medial groove consistently. The crest was located anteroposteriorly between the grooves. CONCLUSIONS: The results of our study suggest a useful measurement technique, a consistent neurovascular pattern, and the need to reconsider the palatal nomenclature.

5-HT(1D) receptor immunoreactivity in the sphenopalatine ganglion: implications for the efficacy of triptans in the treatment of autonomic signs associated with cluster headache.

OBJECTIVE: To determine if 5-HT(1D) receptors are located in the sphenopalatine ganglion. BACKGROUND: While the 5-HT(1D) receptor has been described in sensory and sympathetic ganglia in the head, it was not known whether they were also located in parasympathetic ganglia. METHODS: We used retrograde labeling combined with immunohistochemistry to examine 5-HT(1D) receptor immunoreactivity in rat sphenopalatine ganglion neurons that project to the lacrimal gland, nasal mucosa, cerebral vasculature, and trigeminal ganglion. RESULTS: We found 5-HT(1D) receptor immunoreactivity in nerve terminals around postganglionic cell bodies within the sphenopalatine ganglion. All 5-HT(1D) -immunoreactive terminals were also immunoreactive for calcitonin gene-related peptide but not vesicular acetylcholine transporter, suggesting that they were sensory and not preganglionic parasympathetic fibers. Our retrograde labeling studies showed that approximately 30% of sphenopalatine ganglion neurons innervating the lacrimal gland, 23% innervating the nasal mucosa, and 39% innervating the trigeminal ganglion were in apparent contact with 5-HT(1D) receptor containing nerve terminals. CONCLUSION: These data suggest that 5-HT(1D) receptors within primary afferent neurons that innervate the sphenopalatine ganglion are in a position to modulate the excitability of postganglionic parasympathetic neurons that innervate the lacrimal gland and nasal mucosa, as well as the trigeminal ganglion. This has implications for triptan (5-HT(1D) receptor agonist) actions on parasympathetic symptoms in cluster headache.

The accuracy of identifying the greater palatine neurovascular bundle: a cadaver study.

BACKGROUND: The palate is a common site for harvesting subepithelial connective tissue grafts (SCTG). The size of SCTG that can be harvested is dictated by the position of the greater palatine neurovascular bundle (GPB). The aims of this cadaver study are to assess the accuracy of predicting the location of the GPB on study models and to evaluate anatomic factors that might influence the predictability. METHODS: Eleven fully dentate or partially edentulous maxillary cadavers were used. Study models were fabricated after the greater palatine foramen was identified. The GPB was recognized after dissection, from which the distance to the cemento-enamel junction of the first molar and premolar was measured. Eight periodontists and twelve periodontal residents were asked to estimate the location of the GPB on the study models and the same measurements were taken. Comparisons of the estimated and true GPB position were performed. The correlation between the palatal vault height and the variability of detecting the GPB was investigated. RESULTS: The most frequent greater palatine foramen location was between the second and third molars (66.6%). For most cases, there was an underestimation of the location of the GPB up to 4 mm. The interexaminer variability was positively correlated with the vault height. CONCLUSIONS: The estimated location of the GPB was commonly closer to the cemento-enamel junction of posterior teeth. Agreement on the location of the GPB was lowered with the presence of high palatal vaults. The results of this study could assist clinicians in planning the location for harvesting SCTG on the hard palate.

Augmentation in proximity to the incisive foramen to allow placement of endosseous implants: a case series.

PURPOSE: To assess whether augmentation in the proximity of the incisive foramen with an intraoral bone graft to allow for reliable placement of implants is achievable, not jeopardizing the nasopalatine nerve and vessels in a way causing patients' distress. PATIENTS AND METHODS: Five patients who had lost a central maxillary incisor due to trauma, and in whom a deficiency of bone at the palatal side was present in the proximity of the incisal canal, were augmented with autogenous cancellous bone harvested from the retromolar region. After a healing period of 3 months, implants were inserted. Patients' acceptance, complications, and postoperative morbidity of the procedure were prospectively evaluated by standardized clinical and radiographic examinations up to 12 months after augmentation. RESULTS: At the time of implant surgery, in all cases there was sufficient bone for insertion of the implants with adequate primary stability. Up to now (follow-up of 12-15 months) no fixtures have been lost and all peri-implant tissues have a healthy appearance. All patients were satisfied. CONCLUSION: Augmentation in the proximity of the incisive foramen to enable implant placement appears to be feasible, both from the perspective of the patient and the professional.

Anatomical variation in the position of the greater palatine foramen.

The present study measured the position of the greater palatine foramen relative to adjacent anatomical landmarks in Brazilian skulls. The perpendicular distance of the greater palatine foramen to the midline maxillary suture in Brazilian skulls was about 14 mm and the distance of greater palatine foramen to the incisive foramen was approximately 36 mm. The distance of greater palatine foramen to the posterior border of the hard palate was approximately 3 mm, and the mean angle between the midline maxillary suture and the line from the incisive foramen and the greater palatine foramen was 22.71 degrees . In almost 70% of the cases, the greater palatine foramen opened in an anterior direction. The mean palatine length was approximately 52 mm. In the greater majority of the skulls (93.81%), the greater palatine foramina were opposite or distal to the maxillary third molar. These data will be helpful in comparing these skulls to those from various other regions as well as comparing skulls of different races. It can also provide professionals with anatomical references, in order to block the maxillary division of the trigeminal nerve through the greater palatine foramen. Our results would help clinicians locate the greater palatine foramen in patients with and without upper molars.