Intraosseous vascularization of anterior mandible: a radiographic analysis.

CLINICAL STUDY

Intraosseous Vascularization of Anterior Mandible: A Radiographic Analysis Roberto Di Bari, DDS,* Roberto Coronelli, MD, DDS, and Andrea Cicconetti, MD* Abstract: The anterior mandible was initially considered a safe zone from a surgical point of view. Over time, serious complications resulting from dental implantology procedures have been reported. This has led to a greater focus on vascularization of the interforaminal region. The purpose of this article was to evaluate the anterior mandibular region in relation to the presence of canals perforating the buccal and lingual cortical plates. DICOM (Digital Imaging and Communications in Medicine) files of 100 cone beam computed tomography scans were analyzed by imaging software. All radiographic cross-sections between the mental foramina were examined to detect the presence and location of perforating buccal or lingual canals. Lingual perforating canals are present in 98% of the cohort. The most common site is the symphysis region. The presence of 2 lingual canals cranially and caudally to the genial apophysis has been found in 39%. Vestibular perforating canals are absent in 61%. The anterior mandible has several lingual perforating canals, which are variable in number and location. Imaging software is a valuable aid in presurgical planning. Because of the higher prevalence of perforating canals in the symphysis region, this site should be preserved. Key Words: CBCT (cone beam computed tomography) imaging, mandibular symphysis, vascularization, computed tomography, perforating canals (J Craniofac Surg 2014;25: 872Y879)

T

he anterior mandibular region is of particular anatomical interest in oral surgery for implant rehabilitation. It is also considered a valid intraoral donor site of autologous bone for reconstructive patient needs.1 Previous studies have analyzed the vascularization of the anterior region of the mandible in relation to the hemorrhagic risk during oral surgery.2 The purpose of this article was to evaluate this site in relation to the presence of perforating canals. Differently from the available literature, this study was performed using high-resolution cone beam computed tomography (CBCT) images and three-dimensional reconstructions. The study aimed to analyze both lingual and buccal perforating canals.

From the *Department of Oral and Maxillofacial Sciences, School of Dentistry, Sapienza University of Rome; and †Dr. Coronelli Dental Clinic, Rome, Italy. Received August 10, 2013. Accepted for publication September 30, 2013. Address correspondence and reprint requests to Roberto Di Bari, DDS, Via Simone Martini, 125-00142, Rome, Italy; E-mail: [email protected] The authors report no conflicts of interest. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/01.scs.0000436735.60042.49

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Perforating canals were analyzed in relation to location (horizontal and vertical position), patient’s sex, age, and class of edentulism.

MATERIALS AND METHODS One hundred CBCT scans, all obtained with the same x-ray apparatus (GENDEX GXCB-500; Gendex Dental Systems, Des Plaines, IL) and the same acquiring parameters, were analyzed. The cohort of 100 CBCT scans was composed of 61 female and 39 male patients. The ages of the patients ranged from 19 to 91 years with subjects belonging to each band (Fig. 1). For each case, the dental formula was described, and the edentulism class was evaluated by the Kennedy classification for partial edentulism (Table 1). DICOM (Digital Imaging and Communications in Medicine) files of each CBCT scan were imported on SimPlant (SimPlant 3-D Pro; Materialize, Leuven, Belgium). The software accepts the importation of DICOM format images: the first standard format for sharing and viewing any kind of medical image. Once imported, images were processed in axial, sagittal, and paraxial sections. The images were real x-ray representations of jaw bones (reproduction scale 1:1) and allowed accurate measurements of anatomical structures. DICOM images related to the mandibular region (230 images on 432) were loaded through the “Image Selector” function of SimPlant. Three-dimensional reconstruction of the mandibular region was obtained through the function “Segmentation” of the software; the “scattering” (linked to dentures or metal restorations in the mouth) was removed. The three-dimensional reconstruction was redirected to have the mandible parallel to the floor. Then, using the function “create a panoramic curve,” a referral scout view in relation was selected to which the software had rebuilt all the cross sections (1-mm step). At this point, another tool, “create a nerve” was used to highlight the path of the left and right mandibular canal both in cross section and in the three-dimensional reconstruction. Anterior mandible was defined as the region between the mental foramina, considering a margin of 5 mm medially to them (Fig. 2). All cross sections were analyzed to detect the presence and location of buccal or lingual perforating canals. For each case, the number of lingual and buccal perforating canals was recorded. Regarding canal position, distances from the bottom edge of the cortex (hinf) and from the top edge of the alveolar process (hsup) were measured (Fig. 3). Because of the nature of retrospective study, the present work did not require a specific institutional review board approval. The current study followed the Declaration of Helsinki on medical protocol and ethics.

RESULTS Data on number of perforating canals are presented in Table 2. Depending on the situations encountered, patients were divided into 4 groups and 13 subgroups, characterized by an acronym, as follows: & Patients without canals, with a single homonym subgroup L0+V0Vpatients without canals & Patients with only lingual canals, with 3 subgroups

The Journal of Craniofacial Surgery

& Volume 25, Number 3, May 2014

Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.



Intraosseous Vascularization of Mandible

FIGURE 1. Composition of the cohort by age and sex. The 100 patients, marked with an identification number, were ordered in ascending age; the figure shows a nearly linear distribution of patients’ age in the considered range of 19Y91 years.

L1Vpatients with 1 lingual canal L2Vpatients with 2 lingual canals L3Vpatients with 3 lingual canals & Patients with only vestibular canals, with 2 subgroups V1Vpatients with 1 vestibular canal V2Vpatients with 2 vestibular canals & Patients with lingual and vestibular canals, with 7 subgroups L1+V1Vpatients with 1 lingual canal + 1 vestibular canal L2+V1Vpatients with 2 lingual canals + 1 vestibular canal L3+V1Vpatients with 3 lingual canals + 1 vestibular canal L1+V2Vpatients with 1 lingual canal + 2 vestibular canals L1+V3Vpatients with 1 lingual canal + 3 vestibular canals L2+V2Vpatients with 2 lingual canals + 2 vestibular canals L3+V2Vpatients with 3 lingual canals + 2 vestibular canals On the cohort of 100 patients, 209 canals were detected, including 158 lingual canals and 51 vestibular canals, distributed among the various groups and subgroups as described in the list. Both patients and the detected canals were also divided according to sex of the patients themselves between the various groups and subgroups. The lingual canals have been identified in 98% of the cohort; there are no lingual canals in only 2% of the cohort. Vestibular perforating canals are less frequent: no canal in 61% of cases. In the symphysis region, a single lingual canal was present in 45%. A middle

symphysis structure characterized by 2 lingual perforating canals (located, respectively, cranially and caudally to genial apophysis) was found in 39% of cases. A slightly higher occurrence in males (on average, 2.3 canals for male) than in females (on average, 1.9 canals for female) was recorded. Data on location of perforating canals are presented in Table 3. The distance of lingual perforating canals from the higher alveolar margin (hsup) is 19.11 (SD, 5.61) mm (range, 2.63Y31.39 mm) on average, with a minimum value of hsup (2.63 mm) recorded in edentulous patient. The distance of lingual perforating canals from the lower margin (hinf) is, on average, 10.88 (SD, 4.91) mm (range, 1.23Y19.86 mm). The distance between vestibular canals and the upper alveolar edge (hsup) is, on average, 17.69 (SD, 3.49) mm (range, 9.90Y23.20 mm). The distance between vestibular canals and the inferior mandible margin (hinf) is, on average, 11.07 (SD, 2.00) mm (range, 6.92Y16.56 mm). In Figure 4, the position of lingual perforating canals has been related to the upper alveolar ridge (hsup) and patient’s age: the 158 perforating lingual canals were numbered in such a way as to allow

TABLE 1. Classification of the Cohort According to the Class of Edentulism Class of Edentulism

No. Cases

Full dentition Class IVpartially edentulous Class IIVpartially edentulous Class IIIVpartially edentulous Edentulous Total no. cases

43 14 12 30 1 100

FIGURE 2. Lateral limits (5 mm) from mental holes.

* 2014 Mutaz B. Habal, MD


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TABLE 3. Data on Lingual/Vestibular Canal Location h

Distance From

Lingual canal

hsup hinf

Vestibular canal

hsup hinf

The alveolar ridge The inferior mandible margin The alveolar ridge The inferior mandible margin

Canal

Average Value, mm

SD, mm

Range, mm

19.11 10.88

T 5.61 T 4.91

2.63Y31.39 1.23Y19.86

17.69 11.07

T 3.49 T 2.00

9.90Y23.20 6.92Y16.56

hsup indicates distance from the alveolar ridge; hinf, distance from the inferior mandible margin.

the recognition of the corresponding number of the originating patient with age and sex.

DISCUSSION In the literature, several studies have analyzed the presence of perforating canals in the interforaminal region; over time, various terminologies have been used to describe these structures.3 These studies have used different methods of investigation: examination of traditional x-ray records, multislice CT, CBCT scans, anatomical dissection, magnetic resonance imaging, and Doppler.4

FIGURE 3. Data collected on a lingual canal (hsup = distance from the alveolar ridge; hinf = distance from the inferior mandible margin).

TABLE 2. Presence of Lingual/Vestibular Canals in Cohort Patients

Group

No. Patients

Patients without canals

1

Patients with only lingual canals

60

Patients with only vestibular canals

1

Patients with lingual and vestibular canals

Total

38

100

Subgroup Patients without canals

Canals

Acronym L0+V0

No. Patients 1

Patients with 1 lingual canal

L1

26

Patients with 2 lingual canals

L2

30

Patients with 3 lingual canals

L3

4

Patients with 1 vestibular canal

V1

0

Patients with 2 vestibular canals

V2

1

Patients with 1 lingual canal + 1 vestibular canal

L1+V1

13

Patients with 2 lingual canals + 1 vestibular canal

L2+V1

12

Patients with 3 lingual canals + 1 Vestibular canal

L3+V1

2

Patients with 1 lingual canal + 2 vestibular canals

L1+V2

6

Patients with 1 lingual canal + 3 vestibular canals

L1+V3

0

Patients with 2 lingual canals + 2 vestibular canals

L2+V2

4

Patients with 3 lingual canals + 2 vestibular canals

L3+V2

1 100

Sex

No. Patients

M F M F M F M F M F M F M F M F M F M F M F M F M F M F

1 0 7 19 12 18 3 1 0 0 0 1 4 9 5 7 2 0 3 3 0 0 1 3 1 0 39 61

No. Lingual Canals

No. Vestibular Canals

7 19 24 36 9 3

No. Total Canals

7 19 24 36 9 3

4 9 10 14 6

2 4 9 5 7 2

2 8 18 15 21 8

3 3

6 6

9 9

2 6 3

2 6 2

4 12 5

158

51

209

M indicates male; F, female.

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FIGURE 4. Lingual canal’s position related with patient age (cases sorted in order of age). The figure shows the typical pattern of the trend: the distance of the canal from the alveolar ridge decreases with the age of the patient due to the physiological/pathological resorption of alveolar bone. This trend is not evident with chart data related to hinf because of substantial stability of the mandibular lower margin.

Only dissective studies provide the vascular-nervous content of perforating canals, but the study of their characteristics (frequency, location, diameter, etc) requires a number of analyzed cases that can hardly be obtained with such studies. Radiographic studies allow a wider cohort. Traditional x-ray examinations do not allow a precise identification of the perforating canals, because of beam orientation: canals are visible only when the beam direction coincides with that of the same canals.5 Multislice CT and CBCT images are not affected by this factor and are thus more useful to canal detection.6 The development and widespread use of CBCT technology combine a highly accurate survey with a low biological cost to the patient.4 The resolution distinguishing element of CBCT is the voxel (three-dimensional pixel). The smallest is the voxel, and the most defined is the cone beam imaging.7 Studied CBCT scans have excellent resolution (voxel size, 0.2 mm). Several studies tested the dimensional accuracy of CBCT and the validity of linear and volumetric measurements obtained on them. Most of them experienced no significant statistical differences in accuracy between CBCT and multislice CT; other studies confirmed the congruence between linear measurements performed on CBCT images and measures on anatomical dry mandible.8Y11 A three-dimensional image was created for each analyzed case, achieved through an appropriate density value threshold (Figs. 5A, B). Even if recent studies demonstrate the reliability of

these images,12 all measurements were, however, performed on radiographic cross section. The study of Maloney et al13 tests the hypothesis that linear (vertical and horizontal) measures calculated using a radiographic machine software (I-CAT; Imaging Science International, Hatfield, PA) and SimPlant are as accurate as the criterion standard, represented by measures obtained through a digital gauge on mandibular anatomical sections. They found no statistically significant differences between the various methods. These data confirm the validity of the measurement method adopted in present protocol. At first, anterior mandibular region has been defined. In accordance with the indications emerged in previous works, a surgical operation must provide a safety margin of 5 mm medially to the mental foramina to prevent iatrogenic injury to nervous structures.14 To obtain a greater clinical significance the same parameters were chosen. On 100 CBCT scans, 3 cases of unilateral double mental foramen were found. In such cases, the mesial foramen was chosen as reference margin15 (Fig. 6).

FIGURE 5. A and B, Masks obtained by different thresholding values.

FIGURE 6. Twin mental holes.



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TABLE 4. Elements of Neurovascular Bundle (Lingual Canals)

FIGURE 7. A and B, Single lingual canal in three-dimensional mask (A) and radiographic cross section (B).

The interforaminal region was initially considered a safe zone from a surgical point of view. However, in the literature, serious complications resulting from dental implantology procedures have been reported.2 This may occur during implant’s placement, when the accidental perforation of the lingual cortical plate is caused, with injury to adjacent vascular structures.16 The bleeding causes infarction of the connective tissues of the floor of the mouth. The resulting lifting of the tongue causing upper airway obstruction may necessitate an emergency tracheotomy.17 Some authors believe that injury to the intrabone canals without lingual plate perforation can also cause bleeding that exposes the patient to increased risk of death. This occurs, in particular, in the case of severe mandibular atrophy, if the patient takes anticoagulants for a prolonged period of time, or if he has coagulopathy or hypertension.2,4,18 According to Vandewalle et al,3 the artery present in the perforated canal is of sufficient size to cause severe bleeding, when damaged during oral surgery. According to Gahleitner et al,6 the vessel present in the bone canal is proportional to the original sublingual artery and is therefore able to determine significant intraoperative bleeding. To confirm these observations, Lustig et al19 clearly define how the blood flow within these vessels has an arterial origin and is directed toward the bone: the blood flow was detected in 0.7 to 3.7 mL/min. The study of Eiseman et al20 performed with Doppler

FIGURE 8. A and B, Superior and inferior lingual canal in three-dimensional mask (A) and radiographic cross section (B).

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Neurovascular Bundle (Lingual Canals)

Vascular Element

Nervous Element

Superior lingual canal Inferior lingual canal

Lingual artery Submental artery

Lingual nerve Mylohyoid nerve

and duplex ultrasound technique indicates that there is a decrease in mandibular blood flow as age increases. In the study of vascularization of the mandible, 2 important factors must be taken into account: the edentulism class and the age of the patient. The latter is linked to increased incidence of atherosclerosis in the elderly: this leads to a general reduction in blood supply.20 However, in the mandible, an important role is played by the presence of dental elements, as the alveolar ridge is uniquely vascularized by dental branches of the inferior alveolar artery21: when the tooth is lost, the dental alveolar bone loses the nutritional intake too. Multiple dental extractions can also cause inferior alveolar artery thrombosis resulting in ischemia and atrophy of tissues placed downstream vascular disruption. Castelli et al22 demonstrated the development of a collateral circulation after proximal obstruction of the inferior alveolar artery. A collateral blood supply comes from the sublingual branch of the lingual artery, from 2 branches of the facial artery (submental and inferior labial) and from the hyoid artery. As these arteries are responsible for perforating vessels in the interforaminal region, it is reasonable to expect an increased flow and therefore an increased risk of bleeding in patients with severe atrophy. Some studies show that excessive bleeding during implant placement can affect the healing process, resulting in the proliferation of endothelial cells of blood vessels on the implant surface with impairment of the osteointegration process.4,23 Finally, the nerve ending lesions within the canals were correlated to the incidence of postoperative neurosensory disorders.3 The circulation of the anterior mandible is mediated by 3 major arteries: the inferior alveolar artery (and its branch, mylohyoid artery), the facial artery (and its branch, submental artery), and the lingual artery (and its branch, sublingual artery).4 In fact, it is believed that both the facial and lingual arteries can be damaged as a result of incidents during oral surgery. In an

FIGURE 9. Sublingual region anatomy.





FIGURE 10. A and B, Mandibular canal’s position in edentule (A) and dentate (B) mandible.

emergency situation, it remains a controversial choice to perform external binding of either artery. Manual compression of the antegonial landmark at the bottom edge of the mandible helps to distinguish which of the 2 arteries was injured. If compression of the antegonial landmark stops the bleeding, then the facial/submental artery is most likely the cause.18 Several authors have studied mouth floor vascularization in relation to the interforaminal region, and studies confirm that the vascular structures potentially involved are the submental branch of the facial artery and the sublingual branch of the lingual artery.16 Scientific studies based on anatomical dissection or by using CT examinations confirm that terminal vessels of the sublingual and submental arteries can penetrate the lingual cortical plate of the interforaminal region.24 The main investigated factors were number of canals, localization, diameter, intraosseous direction, content, correlation between presence of canal and sex of the patient, and correlation between canal position and age of the patient. In this work, the lingual canals have been identified in 98% of the cohort. Previous studies found a frequency of canals in the median portion ranging between 85% and 99%.5,25,26 The study of Vandewalle et al3 on macroanatomical evaluation of 354 dried mandibles reveals a similar percentage. Generally, radiographic-based examinations reveal an incidence lower than anatomical studies: high-resolution x-ray image analysis and three-dimensional reconstruction offered by SimPlant have allowed a greater correspondence with anatomical and dissection studies. In this work, the lingual foramen diameters have not been evaluated, as in the literature there are overlapping data. Longoni et al27 refer to a diameter between 0.3 and 1.1 mm (mean value, 0.6 [SD, 0.2] mm). Gahleitner et al6 distinguish the vessel diameter depending on their position: middle position (0.7 [SD, 0.3] mm) and premolar position (0.6 [SD, 0.2] mm). Lustig et al19 refer to a diameter of 0.18 to 1.8 mm. Vandewalle et al3 performed a very thorough investigation on the lingual foramen located in the upper position in respect to the genial apophysis, recording diameter data substantially similar to those described previously. According to the study by Vandewalle et al,3 the shape of the entering foramen appears generally funnel shaped or round. The length of the intraosseous canal course has not been studied in this article, but Romanos et al23 indicate a value between 5 and 15 mm with a mean value of 10.55 mm. Tepper et al26 describe the intraosseous course distinguishing


between the middle and side canals: median canals show a buccal-tolingual course, whereas side canals have a ventral direction. The current study confirms these data. In the middle section, when multiple vessels are present, their intraosseous course frequently appears convergent, thus forming anastomoses between them. An accurate study of perforating bone canals must provide a distinction according to their location. The literature shows that authors have chosen different criteria for topographic grouping of canals from time to time. More frequently, the horizontal position of the canals was placed in relation to dental elements present in that region: thus, there are canals in premolar, lateral incisors, and in the middle section or symphysis region. In the current study, a similar classification was used. However, vessels in the premolar region were not studied, because of a limit of 5 mm from the mental foramina. The study of Gahleitner et al6 reported an incidence of perforating canals in the premolar area of 34% (right side) and 38% (left side). The investigative method of the current study appears similar to that adopted by Longoni et al.27 In their article, they studied the number, location, and size of lingual perforating canals; the analysis was carried out on a cohort of 100 dry mandibles, and the results were compared with those obtained by radiographic analyses performed on CT of the same mandibles. According to the study of Longoni et al,27 most mandibles (45%) present a single lingual canal in the symphysis region; other typical location is the lateral incisor region (Figs. 7A, B). The present work reveals the recurrence (39%) of a middle symphysis structure characterized by 2 lingual perforating canals located, respectively, cranially and caudally to genial apophysis (Figs. 8A, B). This pattern emerges also in the work of Liang et al25: their dissective examination indicates that the upper perforating canal is a terminal branch of the sublingual artery, whereas the lower is a terminal branch of the submental artery (Table 4; Fig. 9). Another pattern is the vertical position of the canal, which could be related with the upper alveolar ridge or with the lower margin of the mandible. In the present work, both of these values have been recorded: hsup and hinf. The distance of lingual perforating canals from the higher alveolar margin (hsup) is 19.11 (SD, 5.61) mm (range, 2.63Y31.39 mm) on average; this result is obviously of surgical interest but is highly influenced by the presence or absence of dental elements and by the degree of resorption of the edentulous sites. Confirming that, a

FIGURE 11. Position of neurovascular bundles in edentule mandible.



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All surgical intervention for bone grafting or placing implants should be preceded by a thorough radiographic analysis of the anterior mandibular region. A careful choice of implant length is required. In relation to the higher prevalence of vascular structures near the midline region, this should possibly be preserved.

REFERENCES

FIGURE 12. A and B, Vestibular canal in three-dimensional mask (A) and radiographic (B) cross section.

minimum value of hsup (2.63 mm) was recorded in the edentulous patient (Figs. 10A, B) (Fig. 11). The studies of Rosano et al28 and Loukas et al29 describe an average distance of a perforating canals from the alveolar margin of 10.3 mm. This difference is related to the class of edentulism of the cohort. The medium hsup evaluated in the current study registers a value halfway between upper and lower perforating canal distance from the genial apophysis in 39% of cases. If only the values of the upper perforating canals were considered, similar values to those of the studies listed above would be obtained. Figure 4 shows the typical pattern of the trend: the distance of the canal from the alveolar ridge decreases with the age of the patient due to the physiological/pathological resorption of alveolar bone. This trend is not evident with chart data related to hinf because of substantial stability of the mandibular lower margin. The distance of perforating canals from the lower margin (hinf) is, on average, 10.88 (SD, 4.91) mm (range, 1.23Y19.86 mm). This value is the same as that recorded by Vandewalle et al3 (10.6 [SD, 1.6] mm) and Gahleitner et al6 (10.0 [SD, 5.5] mm). The choice of the implant length must then be correlated with the presence and location of perforating canals: bicorticalism is no longer considered a key factor,30 and data are emerging supporting the use of short implants.31 In the study of Romanos et al,4 no differences emerged in the frequency of perforating canals between male and female patients. In the current study, a slightly higher occurrence in male patients (on average, 2.3 canals for male patients) than in female patients (on average, 1.9 canals for female patients) was recorded. Vandewalle et al3 suggest differences between ethnic groups. The substantial overlap of the present work’s results (Italian cohort) with those of Vandewalle et al3 (Indian cohort) does not seem to support this hypothesis. The presence of buccal perforating canals was also investigated (Figs. 12A, B). These canals appear smaller than lingual ones. The distance between these buccal vessels and the upper alveolar edge is, on average, 17.69 (SD, 3.49) mm (range, 9.90Y23.20 mm). The anterior mandibular region has many lingual perforating canals, which are variable in number and position. A careful radiographic assessment and a surgical safeguarding of this region appear advisable, especially of the lingual plate (there are no lingual canals in only 2% of the cohort). Particular attention is reserved for edentulous, periodontopathic, and elderly patients: marginal alveolar bone resorption causes a relative superficialization of perforating canals, increasing the chance to intercept them during surgery. Vestibular perforating canals are less frequent: they do not represent a serious surgical risk (no canal in 61% of cases).

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pathogenesis of alveolar ridge atrophy and tooth loss in the elderly? J Oral Maxillofac Surg 2005;63:28Y35 Braun P. Quelque points d’anatomie sur la vascularization arterelles du maxillaire inferieur. Rev Odontostomatol (Bordeaux) 1955;13:98 Castelli WA, Najlet CE, Diaz Perez R. Interruption of the arterial inferior alveolar flow and its effect on mandible collateral circulation and distal tissue. J Dent Res 1975;54:708Y715 Romanos GE, Gupta B, Davids R, et al. Distribution of endosseous bony canals in the mandibular symphysis as detected with cone beam computed tomography. Int J Oral Maxillofac Implants 2012;27: 273Y277 Hofschneider U, Tepper G, Gahleitner A, et al. Assessment of the blood supply to the mental region for reduction of bleeding complications during implant surgery in the interforaminal region. Int J Oral Maxillofac Implants 1999;14:379Y383 Liang X, Jacobs R, Lambrichts I, et al. Lingual foramina on the mandibular midline revisited: a macroanatomical study. Clin Anat 2007; 20:246Y251


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Primary intraosseous ACC of mandible of possible salivary origin: A rare clinical entity.

Intraosseous Neurofibroma of the Mandible: A Case Report and Review of Literature.

Intraosseous salivary gland tissue of the mandible mimicking a periapical lesion.

Radiographic evaluation of mandible to predict the gender and age.

Intraosseous myoepithelial carcinoma of mandible- a case report with clinical, radiological, histopathologic and immuno-histochemical features.

Stafne bone defect in the anterior mandible.

Intraosseous inflammatory myofibroblastic tumor in the mandible: a rare pathologic case report.

Radiographic outcomes of anterior column realignment for adult sagittal plane deformity: a multicenter analysis.

Compound Odontoma in Anterior Mandible-A Case Report.

Primary intraosseous carcinoma of the mandible arising from epithelial remnants of odontogenic cyst.

Anterior maxillary supernumerary teeth: a clinical and radiographic study.

Association of mandible anatomy with age, gender, and dental status: a radiographic study.

Osteosarcoma of the mandible: A case report with an early radiographic manifestation.

The mandible--an analysis.

Primary intraosseous squamous cell carcinoma of the mandible. Is adjuvant therapy still necessary to improve a 5-year survival rate?

Radiographic study of the distribution of maxillary intraosseous vascular canal in Koreans.

Intraosseous blood samples for point-of-care analysis: agreement between intraosseous and arterial analyses.