Incisive Canal Research Articles

Anterior Mandibular Zone Safe for Implants

During implantology procedures, one of the most serious complications is damage of the inferior alveolar nerve (IAN). The mandibular incisive nerve is described as a terminal branch of the IAN and provides innervation to the lower anterior teeth and canines. The incisive nerve and canal are located in the interforaminal area. Although numerous studies report IAN damage during implant placement, few reports in the literature describes sensory disturbances, such as neuropathic pain, related to mandibular incisive nerve damage. The purpose of this retrospective clinical study was to evaluate the risk of neuropathic pain caused by implant placement in the interforaminal region of the mandible. Panaromic radiographs of patients who were treated with dental implants in the Department of Maxillofacial Surgery, Faculty of Dentistry at Erciyes University, between 2007 and 2012, were examined. Fifty-five patients with suspected relationship between mandibular incisive canal and dental implant were included into this study. Computed tomography scans were obtained from 10 patients who have postoperative neuropathic pain. Relationship between dental implant and mandibular incisive nerve was evaluated using a three-dimensional software program. Mandibular incisive nerve perforation by at least 1 implant was observed in all 10 patients. Descriptive analyses were also provided. Neuropathic pain may occur after implant placement in the interforaminal region due to the perforation of the incisive canal and nerve. According to the results of this retrospective study, the incisive canal and nerve perforation should be considered as a complication of implant surgery in the mandibular anterior area.

Uncommon trajectory variations of the mandibular canal and of the mandibular incisive canal: case report

This paper aims to report and discuss a case in which unusual anatomical variations were observed in the mandibular canal (MC) and the mandibular incisive canal (MIC) in a same patient. A 49-year-old healthy female was referred for mandibular dental implant placement. Panoramic radiography and cone beam computed tomography (CBCT) were performed. Cross-sections, axial, coronal, panoramic reconstructions and volume rendering were obtained. The panoramic radiograph did not show any evidence of abnormality. CBCT showed a bifid MC on the right side. It extended to the buccal cortex, exteriorized for 6mm and returned to its conventional trajectory to reach the mental foramen. On the left side, the MIC initially followed its normal trajectory for 4mm but, in the canine region, it also extended to the buccal cortex and exteriorized. The advent of CBCT in Dentistry allowed a greater accuracy in the diagnosis of anatomical variations in the jaws, preventing injury to the neurovascular bundle and enabling an adequate surgical planning in the region.

Morphological characterization of the nasopalatine region in human fetuses and its association to pathologies

The nasopalatine region is composed of structures such as the vomeronasal organ and nasopalatine duct. The nasopalatine duct may provide the communication of the mouth to the nasal cavity in human fetuses and can be obliterated in an adult human. Knowledge on the development of the nasopalatine region and nasopalatine duct in humans is necessary for understanding the morphology and etiopathogenesis of lesions that occur in this region.Objective:The aim of the present study was to describe the morphological aspects of the nasopalatine region in human fetuses and correlate these aspects with the development of pathologies in this region. Material and Methods:Five human fetuses with no facial or palatine abnormalities were used for the acquisition of specimens from the nasopalatine region. After demineralization, the specimens were histologically processed. Histological cuts were stained with methylene blue to orient the cutting plane and hematoxylin-eosin for the descriptive histological analysis. Results:The age of the fetuses was 8.00, 8.25, 9.00 and 9.25 weeks, and it was not possible to determine the age in the last one. The incisive canal was observed in all specimens as an opening delimited laterally by the periosteum and connecting oral and nasal cavity. The nasopalatine duct is an epithelial structure with the greatest morphological variation, with either unilateral or bilateral occurrence and total patent, partial patent and islet forms. The vomeronasal organ is a bilateral epithelized structure located alongside the nasal septum above the incisive canal in all the fetuses. Conclusions:The incisive canal, nasopalatine duct and vomeronasal organ are distinct anatomic structures. The development of nasopalatine duct cysts may occur in all forms of the nasopalatine duct.

Cone-beam CT evaluation of morphology, location, and course of mandibular incisive canal: considerations for implant treatment

Objectives The purpose of the present study was to assess the presence and course of the incisive canal (IC) in the mental interforaminal region according to dental status, age, and sex using cone-beam computed tomography (CBCT).

Nasopalatine duct cyst

The nasopalatine duct cyst, also known as a nasopalatine cyst or incisive canal cyst, is a developmental, non-neoplastic cyst that is considered to be the most common nonodontogenic cyst. It is one of many pathological processes that may occur within the jawbones. This article reports the case of a

Retrospective Study of the Anterior Loop of the Inferior Alveolar Nerve and the Incisive Canal Using Cone Beam Computed Tomography

The mental foramen is an important landmark during surgical procedures such as osseous grafting or the placement of dental implants. To avoid injuring the mental nerve, it is important both to carefully assess the location of the mental foramen and to determine whether an anterior loop of the mental nerve or the incisive canal lies mesial to it. The objective of this study was to quantify the ability of cone beam computed tomography (CBCT) to measure the length of the mental nerve loop, the length and diameter of the incisive nerve canals, and the incisive canal path. The study included 352 CBCT scans that had originally been used for preoperative planning of implant placement in the interforaminal region of the anterior mandible. For each scan, the length of the mental nerve loop and the length, diameter, and path of the incisive canal were determined. Mean values were compared between groups based on sex, right versus left side, and whether the patient was edentulous. The inferior alveolar nerve loop and incisive canal had a mean length of 2.40 ± 0.93 mm and 9.11 ± 3.00 mm, respectively. The mean incisive canal diameter was 1.48 ± 0.66 mm and showed a downward path in 51.3% of CBCT images and a linear or upward path in 38.29% and 10.41% of scans, respectively. CBCT provides an accurate means to identify critical anatomical features in the anterior mandible during preoperative surgical planning.

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

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. 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. 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. 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.

The Dimensions of the Mandibular Incisive Canal and Its Spatial Relationship to Various Anatomical Landmarks of the Mandible: A Study Using Cone Beam Computed Tomography

Often during implant surgery in the mandibular symphysis area, little attention is given to the mandibular incisive canal. Although it is true that intraoperative and postoperative complications with implants in the incisive mandibular canal are rare, they are more common when harvesting bone from the chin area. Loss of tooth sensation is a rather frequent consequence. The present study used cone beam computed tomography (CBCT) to identify and measure variations in the dimensions of the incisive canal and its spatial relationship to various anatomical landmarks of the mandible to reduce the number of postoperative complications after selective procedures in the symphysis area. One hundred two patients scanned for a variety of clinical indications were included in this retrospective study. The dimensions of the incisive mandibular canal were assessed, and the distances from the various mandibular landmarks were measured using the multiplanar capabilities of the CBCT device's software. The results show that a mandibular incisive canal was identified by CBCT in 93% of the cases and had a mean length of 8.9 mm (range, 0 to 24.6 mm). The mean distances of the canal from the root tips of the premolars, canines, and incisors were 6.9 mm, 7.3 mm, and 10.4 mm, respectively. The mean distances from the canal to the buccal cortical border in the same tooth positions were 2.8 mm, 4.4 mm, and 4.8 mm, respectively. In a large majority of the sample, a mandibular incisive canal was identified by CBCT. The large variation in the spatial relationships of the canal mandates a case-by-case preoperative radiographic evaluation of the canal, and CBCT seems able to fulfill the task.

Mandibular Incisive Canal: A Cone Beam Computed Tomography Study

ABSTRACTThe aim of this study was to assess the presence, width, and initial part of the mandibular incisive canal (MIC) and its relation with the mental foramen (MF), by means of cone beam computed tomography (CBCT).The study material included 140 CBCT scans taken for preoperative planning of implant placement. CBCT data were examined carefully by three experienced observers for the presence and location of the initial part of the MIC and its relation with the MF. The inner diameter of the MIC at the beginning of the canal was measured three times by one observer.The interobserver agreement in identification of the MIC was excellent (mean kappa value of 0.84). A MIC was found in 92.9 % of cases. The mean inner vertical diameter of the canal was 1.44 mm ± 0.39 mm. The diameter of the canal reached 2.5 mm at maximum. The canals in males and these on the right side of the mandibles were significantly wider. The majority of the MICs—86.3 % (n = 195), began before the MF (type 1); the rest of them—13.7 % (n = 31), began extremely close to the foramen (type 2). The MIC is an almost permanent finding on CBCT scans. In cases when the MIC begins at the level of the mental foramen (type 2) the lingual positioning of the implants could save the neurovascular bundle in the canal. All this will lead to better conditions for osteointegration and prevent eventual neurosensory disturbances.

Nasopalatine duct cyst or periapical pathology: An enigma

Nasopalatine duct cyst NPDC also known as nasopalatine canal cyst or incisive canal cyst, is a developmental, non-neoplastic cyst arising from degeneration of nasopalatine ducts. These ducts usually regress in fetal life. The persistence of ductal epithelium leads to formation of cyst. Development of cyst is attributed or triggered by several factors like infection 38%, trauma 16%, minor salivary mucus retention, inflammatory stimulus, spontaneous proliferation of epithelial remnants present in the nasopalatine duct. Radiographically they are seen as a solitary well-defined, oval or round unilocular radiolucency, between central incisors, >0.6 cm in diameter. They may appear heart-shaped if the anterior nasal spine superimposed. In this article a case of NPDC with a history of trauma is described. Its diagnosis was based on clinical, radiographic, and histologic findings. The nasopalatine cyst requires no surgical treatment when it is small and asymptomatic. In rare cases it increases in size and may even destroy bone. In this case report we have described surgical management of the lesion with postoperative follow-up for 1 year.

Transnasal Endoscopic Marsupialization for a Huge Nasopalatine Duct Cyst With Nasal Involvement

Nasopalatine duct cysts (NPDCs), also known as incisive canal cysts, are the most common nonodontogenic cyst of the jaw, with a reported prevalence of between 1% and 11.6% of all jaw cysts. A developmental cyst, the NPDC is believed to arise from epithelial remnants of the nasopalatine duct, the communication between the nasal cavity and anterior maxilla in the developing fetus. Precipitating factors in the development of an NPDC have been reported to be trauma, infection, and spontaneous occurrence.

내시경을 이용한 거대 비구개관낭의 조대술 1예

The nasopalatine duct cyst is the most common cyst of nonodontogenic origin in the maxilla. It occurs approximately 1% of the population. Currently, it’s origin is thought to be from oronasal ducts within the incisive canal, however it is still a source of controversy. The etiology still remains unknown. Possible causes include trauma, infection, spontaneous proliferation. Symptoms were reported include swelling, drainage and pain. Radiographically, nasopalatine duct cyst usually appear as a round , ovoid or heart shaped radiolucent mass in the anterior palate. Surgical enucleation is the recommended treatment. However, if the size of cystic is above 2 cm and there is a risk of oroantral fistula after enucleation, marsupialization is indicated. The authors report a case of a large nasopalatine duct cyst which is treated with endoscopic marsupialization. (J Clinical Otolaryngol 2012;23:292–295)

Volumetric CBCT analysis of the palatine process of the anterior maxilla: a potential source for bone grafts

The aim of this research was to use cone-beam computerized tomography (CBCT) to analyze the available bone volume in the palatine process of the maxilla (PPM), which is a potential source of bone grafts. 20 CBCT scans were evaluated. From the most caudal axial slice of the PPM, the bony surface was calculated cranially up to the nasal floor. The predetermined thickness of each slice was 0.9mm. A 2mm safety margin was established considering the incisive canal and teeth 14–24. A ±0.1mm error deviation was established for all calculations. By connecting these points and those defined at the posterior bone boundary, a surface was obtained. A three-dimensional (3D) image of the delimited zone was constructed and analyzed using 3D imaging software. The study comprised 6 women and 14 men (mean age 39.4±11.5 years). Calculated bone volume averaged 2.41±0.785cm3. The palatine process of the maxilla contains a considerable bone volume (2.41±0.785cm3). This area should be regarded as a potential donor site for the regeneration of maxillary atrophic bones. Further investigation is required before these findings lead to routine clinical application.

Letter to the Editor

To the Editor: Recently, an interesting research article by Romanos et al1 was published that related the frequency, and the importance, of the mandibular incisive canal (MIC) and its nerve in preoperative planning for implant surgery. For most surgeons, the anatomy and content of the MIC are controversial,2–5 and in many books or articles, there is no reference to its existence,6–8 whereby the anterior mandible region is considered a safe area for implant placement. However, the high rate of incidence reported in anatomical and imaging studies conclude that the MIC (and its nerve) corresponds to a constant anatomical structure rather than an anatomical variation,5,8 with an origin at the level of mental foramen, term at the apex of the mandibular lateral incisor, and an average diameter between 1.8 (±0.5)5,9 and 1.48 (±0.57) mm.1 Neurosensory disorders have been reported after installation of implants in the anterior region of the mandible.6,10,11 Other complications such as bruising and swelling during or after surgical procedures, or even a traumatic neuroma,10 can arise due to direct7,10 or indirect6,9 trauma of the canal or it's nerve. Another complication is the failure of osseointegration because of the migration of soft tissue around the implant.7 The high detection rate of MIC by cone beam computed tomography indicates the high value of the analysis for preoperative surgical procedures in the anterior mandibular area.3 Current evidence has described the microsurgical approach by endoscopic visualization of neurovascular structures in oral surgery and implantology, including MIC and its nerve,2,3,12 as we can see in Figure 1, which uses an immersion endoscopic technique for precise location and removal of the mandibular incisive nerve after implant placement. Mandibular incisive nerve and other nerves of the maxillofacial area have rarely been seen with this quality and amplification.Fig. 1: A, Evaluation of the visibility and the course of the mandibular incisive canal using cone-beam computed tomography. B, Intraoperative visualization by immersion endoscopy (Karl Storz 1.9mm diameter) of mandibular incisive nerve (terminal branch) prior to resection in the area of implant placement. Red arrow indicates the osseous border of the mandibular incisive canal and white arrow its nerve.The presence, and anatomy, of the MIC and its nerve should not be ignored in the planning of implants and other surgical procedures in the anterior mandible. This could play a fundamental role in avoiding any risk of neurovascular damage and obtaining successful osseointegration. We agree with Romanos et al1 that there is no doubt that orthopantomographs underestimate the real presence of MIC and a more precise examination should be taken into consideration when surgical procedures in this anatomical area have to be performed. Cone beam computed tomography is recommended to identify these structures before any surgical procedure in this region, along with the use of intraoperative endoscopy for a successful outcome (see Fig. 1 A and B).

Fibrosis after surgically assisted rapid maxillary expansion mimicking an incisive canal cyst: Case report

Fibrosis after surgically assisted rapid maxillary expansion mimicking an incisive canal cyst: Case report

Brisk, Pulsatile Bleeding From the Anterior Mandibular Incisive Canal During Implant Surgery

Dental implant surgery in the anterior mandible is considered a relatively routine and safe procedure with minimal morbidity. A case of brisk, pulsatile bleeding from the anterior mandibular incisive canal and its management using an active hemostatic matrix is presented. In addition, a review of the literature regarding the anatomy of this region of the mandible and hemostatic strategy to achieve hemostasis will be discussed.

Accessory foramen in the human mandible: anatomical and clinical considerations

We read with interest the published article ‘Anatomical classification of accessory foramina in human mandibles of adults, infants, and fetuses’ by Przystanska and Bruska (2012). The authors performed a meticulous study of the accessory foramen in the mandible. We wish to share few scientific facts related to the published topic. It is always better to visualize an accessory foramen in a radiograph. The best possible means is to insert a wire and visualize the continuity of the canal. An accessory foramen is meant for passage of the neurovascular structures. It would be better to interpret the concerned neurovascular structures according to the position of the accessory foramen. A past study cut the mandible in the midline and measured the dimensions of the canal under dissecting microscope (Liang et al. 2007). Even though the accessory foramina were discussed, no speculation was made about the blood vessels or nerves traversing it. The authors mentioned in their discussion that the accessory foramen was connected to the mandibular foramen. Radiographic investigations may provide exact evidence continuity of the accessory foramina with the mandibular canal but it is quite difficult to believe such in the absence of radiographic studies. The accessory foramen has also been reported to have continuity with the incisive canal (von Arx et al. 2011). If there is continuity of the accessory foramen with the mandibular canal, one wonders if the mental nerve emerges out through this foramen. This raises serious issues for successful nerve blocks. Previous studies have described consideration of additional locoregional anaesthesia in the case of failed mandibular block anesthesia (von Arx et al. 2011). In the second paragraph of the results section, under the subheading Adult mandibles, it was mentioned that four different types of foramina were found but only three were mentioned in pointwise form. We wonder if this really refers to types of foramina or do the authors mean different positions of the foramina. Contrary to the present findings, past research studies depict the accessory foramen varying according to age and race (Kaufman et al. 2000). Interestingly, an earlier study speculated that eruption of wisdom teeth may require additional neurovascular nourishment (von Arx et al. 2011). The present study should have discussed the eventualities of eruption of wisdom teeth or even additional dental spurs. Calculation of the mean distance of this canal with respect to a bony point may have been more beneficial to maxillofacial surgeons. These may be needed for planning graft implants. We congratulate the authors for their valiant effort, and thank the editors for publishing an interesting topic.

The Presence of the Mandibular Incisive Canal

The mandibular incisive canal (MIC) is the anterior extension of the mandibular canal and its presence is of interest in surgical procedures in the chin region. The aim of this study was to investigate the presence of a MIC in panoramic radiographs (OPGs). One thousand forty-five OPGs were randomly chosen from patient population. The data collected included patient characteristics and MIC presence/absence according to the type of the dentition. Measurements (in mm) were performed evaluating the following: (A) minimum and (B) maximum distance from the alveolar ridge; (C) thickness and (D) length of the canal; and (E) distance (in bilateral cases) between the canals. The MIC was found in 2.7% of the patients. This study demonstrates the frequency of the MIC in OPGs and suggests that this anatomical structure should be considered to prevent injury during surgery.

Is there a gender difference in anatomic features of incisive canal and maxillary environmental bone?

The effect of gender on anatomic structures and various body systems were illustrated in the literature. The purpose of this study was to identify the influence of gender and tooth loss on incisive canal characteristics and buccal bone dimensions in the anterior maxilla. Computed tomographies (CTs) of 417 male and 516 female patients in four dental clinics were included in this study. The diameter and the length of the incisive canal; width and the length of the bone anterior to the canal; palatal bone length, root length, and root width of the central incisor teeth were measured and recorded from CT sections. Mean incisive canal length was 11.96±2.73mm and 10.39±2.47mm in men and women, respectively, (P<0.05). In men, mean canal diameter was 2.79±0.94mm whereas in women it was 2.43±0.85mm and this difference was statistically significant (P<0.05). Men had significant higher buccal bone dimensions (length and width of the bone anterior to the canal) than women. Absence of teeth in the anterior maxilla decreased incisive canal length and buccal bone dimensions; however, canal diameter remain unchanged. Present results suggested a gender related differences in anatomic features of incisive canal and surrounding buccal bone. In addition, crestal canal diameter, buccal bone length, and thickness parameters might be different in distinct countries.

Evaluation of Maxillary Incisive Canal Characteristics Related to Dental Implant Treatment With Computerized Tomography: A Clinical Multicenter Study

A close anatomic relationship between the incisive canal and the roots of the central maxillary incisors should be kept in mind during dental-implant treatment in the anterior maxilla. The aim of the present study is to analyze incisive canal characteristics on computed tomography (CT) sections and to evaluate its relation to bone anterior to the canal with regard to dental implantation. A total of 933 partially edentulous and/or edentulous patients scheduled for implant insertion in four dental clinics enrolled in the present study. The following were measured and recorded from CT sections for analysis: 1) diameter and length of the incisive canal; 2) width and length of the bone anterior to the canal; 3) palatal bone width and length; and 4) root width and length of the central incisor. Mean canal length was 10.86 ± 2.67 mm, and mean diameter was 2.59 ± 0.91 mm. Canal length was shortened in edentulous anterior maxilla compared to dentate maxilla. However, canal diameter did not show any difference between dentate and edentulous groups. Males had a longer and wider incisive canal than females. Canal shape was mostly cylindrical in 40.73% of images. No correlation was found with mean canal length and mean canal diameter according to age. Although variations exist in every patient, the findings from this study suggest that sex and dental status are important factors that can affect incisive canal characteristics and amount of bone anterior to the canal. Clinicians should perform careful planning using CT scans before performing dental implant surgeries in premaxillary region.