Abstract
Aim
Placement of implants in the maxillary anterior region needs to be preceded by careful analysis of the area as in addition to the functional aspect the esthetic outcome is of prime importance. This descriptive study evaluated anatomical characteristics and dimensions of the nasopalatine canal (NC) from coronal, sagittal and axial aspects using cone beam computed tomography (CBCT) giving it a three dimensional analytical approach. Also the dimensions of the corresponding buccal bone plate (BBP) of the alveolar process were evaluated. Additionally, the influence of age and gender on these characteristics was also analyzed.
Methods
A total of 81-CBCT scans of patients with one or no upper central incisors present were selected. Sagittal slices were used for measurements of the NC and BBP and to evaluate shape of the NC. Coronal slices were used to assess NC shape and axial slices to assess number of incisive foramina and foramina of Stenson.
Results
The most prevalent canal shape was: cylindrical (48.14 %) in sagittal aspect; Y-type (49.38 %) in coronal aspect; and one incisive foramen with two Stenson’s foramina [1–(2–5)] (60.49 %) in axial aspect. Mean NC length was 11.13 ± 3.23 mm; statistically significant differences were detected between genders (p < 0.001). Mean nasopalatine angle was 69.32° ± 7.70. Mean BBP length was 17.12 ± 3.97 mm and mean BBP width was 5.71 ± 1.29 mm, significant differences were detected between genders (p < 0.001).
Conclusion
The current study demonstrates variability of the NC in terms of anatomical characteristics and dimensions; hence, a thorough CBCT analysis is highly recommended for better surgical outcomes and to reduce the post-operative complications in implant dentistry.
Keywords: Anterior maxilla, Cone beam computed tomography, Dental implants, Nasopalatine canal, Buccal bone plate
Introduction
Rehabilitation of the anterior maxilla with osseointegrated dental implants has become a common treatment protocol over the last few years. In this region, patients often ascribe more importance to the esthetic outcome over the functional aspects of the implant restoration [1].
Failure of implant treatment generally leads to removal of the implant followed by complex tissue and bone augmentation procedures [2]. Contact of implant with the surrounding neural tissue results in the failure of osseointegration and can also cause some sensory dysfunctions [3].
The pattern of buccal bone plate (BBP) resorption after tooth extraction has been studied by many authors [4–6]. Cawood and Howell [4] observed that the pattern of bone loss in the maxilla varies from that in the mandible. The pattern of bone resorption in the anterior maxilla is generally horizontal, from the buccal surface to the palatal surface [4]. The volume and anatomical characteristics of the bone in anterior maxilla generally poses an anatomical constraint while restoring with implants. Keeping these complications in mind, the anatomic morphology and dimensions of the nasopalatine canal (NC) and corresponding BBP should be carefully evaluated before implant placement in its vicinity.
The NC is generally located in the midline of the palate, posterior to the maxillary central incisors [7]. The NC has an oral opening in the midline of the anterior palate and is known as the incisive foramen, and is located immediately below the incisive papilla. The canal divides into two canaliculi on its way towards the nasal cavity, and terminates at the nasal floor with an opening, known as the foramina of Stenson, at either side of the septum [8]. The canal consists of the incisive nerve and the terminal branch of the descending nasopalatine artery, fibrous connective tissue, fat and even small salivary glands [9]. There are numerous anatomical variations of the NC which are not very well documented in the literature and are often only presented as case reports [3, 7, 10].
Traditionally, two-dimensional methods like intra-oral radiography and panoramic imaging have been recommended in the literature for diagnostic imaging of the anterior maxilla. However, the introduction of cone beam computed tomography (CBCT) has created new diagnostic possibilities in dentistry. CBCT scans have made it possible to analyze anatomical variations of the NC [11, 12] and to determine the degree of BBP resorption in the anterior maxillary region after tooth loss [4–6, 13, 14]. Keeping in mind that the NC may occupy up to 58 % of the BBP width [15], a precise 3-dimensional (3D) anatomic description of the NC to enable safe and accurate surgical planning and placement of dental implants is necessary [16]. To the best of our knowledge, there is no scientific evidence to correlate the tridimensional NC shapes.
The aim of this study was to conduct three-dimensional analysis of the anatomical characteristics and dimensions of the NC and the corresponding BBP using CBCT. Additionally, the influence of age and gender on these findings was also evaluated.
Materials and Methods
Patient Selection
A total of 81-CBCT scans of patients with one or no upper central incisors present were selected. All scans were of patients referred to an imaging center (Insight CBCT, Mumbai, India) by private dentists for treatment planning of various oral surgical procedures. Written informed consent was obtained from all the patients who participated in this study. The institutional review board and ethics committee approved the research.
The inclusion criteria were as follows: (1) patients above 18 years of age; (2) CBCT with a voxel size of 0.125 mm; (3) one or no upper central incisors present. The exclusion criteria were: (1) impacted teeth in the area of interest; (2) presence of any lesion; (3) root pieces present; (4) dental implants in the region of interest; (5) any suspected NC pathology (cyst); (6) bone grafts.
Imaging Procedures
The CBCT images were obtained using an iCAT 17-19 CBCT scanner (Hatfield, Pennsylvania, USA) with a voxel size of 0.125 mm and a beam diameter of 16 × 13 cm. Operating parameters were set at 3 mA and 80 kV and exposure time was 17.5 s. The data was reconstructed with slices at an interval of 0.25 mm, positioned parallel to the horizontal axis of the alveolar bone. The slices were reformatted to place the NC in a vertical position in the coronal view, and the palate/floor of the nose in a horizontal position in the sagittal view.
Image Evaluation
The data was analyzed using i-CAT Vision software (i-CATVision 1.9, Imaging Sciences International, Inc., Hatfield, Pennsylvania, USA).
Images were evaluated from the sagittal, coronal and axial aspects to give it a three-dimensional analytical approach. All dimensional measurements of NC and BBP were made on sagittal slices. The shape of the NC was evaluated from the sagittal and coronal aspects. Axial slices were used to assess the number of incisive foramina (oral/palatal openings) and foramina of Stenson (nasal openings).
Evaluation from the Sagittal Aspect
The following landmarks were selected for standardized measurements of NC and BBP (Fig. 1)
NC length was defined as the distance from the incisive foramina to foramina of Stenson. If the canal was of anatomic type B or C, the length was calculated as a mean value of the different canal measurements.
Nasopalatine angle was defined as the intersection of the NC length (1) and tangent line crossing the nasal floor to the anterior nasal spine.
The diameter of the nasal foramen. If the NC was of anatomic type B or C, the diameters of all visible nasal foramina were added together, and a mean value was calculated.
The diameter of the incisive foramen. If the NC was of anatomic type B, the diameters of the palatal openings were added together, and a mean value was calculated.
BBP length was calculated by joining midpoints of coronal bone ridge width (as a line joining the buccal cortical and palatinal cortical at cortical level of BBP) and apical ridge width (was a line joining the buccal cortical and palatinal cortical at apical level of BBP).
BBP width was calculated by plotting a perpendicular line to BBP length at one-third of the coronal BBP length.
Fig. 1.
Diagram showing the landmarks selected for evaluation of the different anatomical characteristics of NC and BBP from the sagittal aspect (1 NC length, 2 nasopalatine angle, 3 BBP length and 4 BBP width)
In sagittal slices, the anatomic variants of the NC shape were classified into four groups: (1) funnel-like, (2) cylindrical, (3) hourglass-like and (4) banana-like (Fig. 2).
Fig. 2.
Anatomic variants of the NC shape in the sagittal slices (a cylindrical, b funnel-like and c hourglass-like)
Evaluation from the Coronal Aspect (Fig. 3)
Fig. 3.
Anatomic variants of the NC shape in the coronal slices (a single canal, b two parallel canals, c Y-type canal with one incisive foramen and two or more foramina of Stenson)
In coronal slices, the anatomic variants of the NC shape were classified into three groups: (1) a single canal, (2) two parallel canals and (3) variations of the Y-type canal with one incisive foramen and two or more foramina of Stenson.
Evaluation from the Axial Aspect (Fig. 4)
Fig. 4.
Axial classification of NC (a one incisive foramina, b one foramina of Stenson and c three foramina of Stenson)
In axial slices, the anatomic variants of the NC were classified according to the number of incisive foramina and the number of foramina of Stenson. The groups were identified with two or three digits, the first digit corresponds to the number of openings in the incisive foramina and the second and third digits correspond to the number of openings in the foramina of Stenson. The axial groups were: (1–1), [1–(2–5)], [2–(2–4)] and [3–(1 and 3)].
Statistical Analysis
The data collected was analyzed using descriptive statistics and also the 95 % confidence intervals of the mean outcome measures for each patient subgroup were calculated. The t test or one-way ANOVA, was appropriately selected for comparison of differences in CBCT measurements (NC and BBP) between patient subgroups.
Pearson’s correlation was used to evaluate the association between measurements and patient age. A multivariant linear regression model (MLRM) was used to predict the relation between measurements, age and gender.
The significance level chosen for all statistical tests was p ≤ 0.05. All analyses were performed using a software package (S-Plus Professional Version 6.2, Insightful Software, Palo Alto, CA, USA).
Results
A total of 81 CBCTs were evaluated in this study. The study group comprised of 35 males (43.2 %) and 46 females (56.8 %) with a mean age of 44.37 ± 14.78 years (Table 1). The mean NC length was 11.13 ± 3.23 mm; mean nasopalatine angle was 69.32° ± 7.70°; mean incisive foramina diameter was 4.23 ± 1.89; mean nasal foramina diameter was 3.41 ± 1.47; mean BBP length was 17.12 ± 3.97 mm and mean BBP width was 5.71 ± 1.29 mm (Table 1).
Table 1.
Descriptive results
| Parameters | Range | Mean | SD |
|---|---|---|---|
| Age | 18.00–77.00 | 44.37 | 14.78 |
| NC length (mm) | 5.18–22.18 | 11.13 | 3.23 |
| Nasopalatine angle (°) | 44.00–87.00 | 69.32 | 7.70 |
| Incisive foramina diameter (mm) | 2.88–6.86 | 4.23 | 1.89 |
| Nasal foramina diameter (mm) | 2.16–5.14 | 3.41 | 1.47 |
| BBP length (mm) | 6.12–27.79 | 17.12 | 3.97 |
| BBP width (mm) | 2.84–8.12 | 5.71 | 1.29 |
With respect to sagittal shape, the most prevalent canal shape was cylindrical in 39 cases (48.15 %) (Table 2), followed by hourglass-like in 25 cases (30.9 %) and funnel-like in 17 cases (20.9 %) (Table 2).
Table 2.
The highest frequency observed in each NC classification
| NC classification | Frequency | Percentage |
|---|---|---|
| Sagittal shape—cylindrical | 39 | 48.14 |
| Coronal shape—’Y’ type canal | 40 | 49.38 |
| Axial classification 1–(2–5) | 49 | 60.49 |
Anatomic variations in the coronal slice were the following: Y-type canal was the most frequent with 40 cases (49.4 %) (Table 2), a single canal was observed in 33 cases (40.7 %), two parallel canals in 8 cases (9.9 %).
Regarding the number of foramina in the axial slice, the more frequent finding was one foramen incisive with two to five foramina of Stenson {1–(2–5)} in 49 cases (60.5 %) (Table 2). Other categories were (1–1) in 19 cases (23.4 %), followed by {2–(2–4)} in 8 cases (9.9 %) and {3–(1 and 3)} in 5 cases (6.2 %).
With respect to gender, the NC length for males (mean 11.87 mm) presented a longer canal than females (mean 10.53 mm) and this difference was statistically significant (p = 0.013). Males presented a wider angle (mean 73.45°) than females (mean 67.98°), although no statistically significant differences were found (p = 0.327). Males had a wider incisive foramina diameter (mean 4.53 mm) as compared to females (mean 3.98 mm), but this difference was statistically insignificant (p = 0.457). Males also had a wider nasal foramina diameter (mean 3.63 mm) as compared to females (mean 3.19 mm), but this difference was also statistically insignificant (p = 0.362). The BBP length for males presented a higher mean value (17.72 mm) than females (16.68 mm), but this difference was not statistically significant (p = 0.121). The BBP width was significantly different (p = 0.009) between males (mean 6.38 mm) and females (5.21 mm) (Table 3).
Table 3.
Effect of gender on the NC and BBP dimensions
| Dimensions | Male | Female | p value |
|---|---|---|---|
| NC length (mm) | 11.87 | 10.53 | 0.013* |
| Nasopalatine angle (°) | 73.45 | 67.98 | 0.327 |
| Incisive foramina diameter (mm) | 4.53 | 3.98 | 0.457 |
| Nasal foramina diameter (mm) | 3.63 | 3.19 | 0.362 |
| BBP length (mm) | 17.72 | 16.68 | 0.121 |
| BBP width (mm) | 6.38 | 5.21 | 0.009* |
* Statistically significant differences (p ≤ 0.05)
No statistically significant differences were found with respect to the sagittal shape of the canal and the dimensions of NC and BBP (Table 4).
Table 4.
Effect of sagittal shape of the canal on NC and BBP dimensions
| Parameters | Sagittal shape | N | Mean | SD | F | p |
|---|---|---|---|---|---|---|
| Age | Cylindrical | 39 | 45.22 | 12.38 | 2.957 | 0.051 |
| Hourglass like | 25 | 46.76 | 15.78 | |||
| Funnel like | 17 | 41.22 | 14.67 | |||
| NC length (mm) | Cylindrical | 39 | 11.86 | 2.34 | 1.465 | 0.218 |
| Hourglass like | 25 | 10.22 | 3.14 | |||
| Funnel like | 17 | 11.43 | 1.98 | |||
| Nasopalatine angle (°) | Cylindrical | 39 | 64.28 | 8.85 | 0.143 | 0.857 |
| Hourglass like | 25 | 70.47 | 7.27 | |||
| Funnel like | 17 | 73.21 | 9.42 | |||
| Incisive foramina diameter (mm) | Cylindrical | 39 | 4.56 | 0.98 | 0.254 | 0.769 |
| Hourglass like | 25 | 4.78 | 1.12 | |||
| Funnel like | 17 | 4.28 | 0.78 | |||
| Nasal foramina diameter (mm) | Cylindrical | 39 | 3.47 | 0.67 | 0.312 | 0.674 |
| Hourglass like | 25 | 3.89 | 0.88 | |||
| Funnel like | 17 | 2.99 | 0.58 | |||
| BBP length (mm) | Cylindrical | 39 | 17.28 | 4.56 | 0.311 | 0.746 |
| Hourglass like | 25 | 16.57 | 3.98 | |||
| Funnel like | 17 | 17.47 | 4.63 | |||
| BBP width (mm) | Cylindrical | 39 | 5.45 | 1.21 | 0.159 | 0.858 |
| Hourglass like | 25 | 5.88 | 1.47 | |||
| Funnel like | 17 | 5.84 | 1.48 |
Regarding coronal slice, the NC length was significantly different between the single and two parallel canal groups and between the two parallel and Y-type canal groups (p = 0.002). There was a significant difference between the NC angle between single and Y type canal (p = 0.037). The difference between the incisive foramina diameter of two parallel canal and Y-type canals was also statistically significant (p = 0.002) (Table 5).
Table 5.
Effect of coronal shape of the canal on NC and BBP dimensions
| Parameters | Coronal shape | N | Mean | SD | F | p |
|---|---|---|---|---|---|---|
| Age | Single canal | 33 | 45.68 | 11.17 | 0.792 | 0.418 |
| Two parallel canals | 8 | 42.56 | 16.68 | |||
| Y-type canal | 40 | 44.35 | 13.07 | |||
| NC length (mm) | Single canal | 33 | 12.47 | 1.67 | 5.678 | 0.002* |
| Two parallel canals | 8 | 10.31 | 2.14 | |||
| Y-type canal | 40 | 12.32 | 3.57 | |||
| Nasopalatine angle (°) | Single canal | 33 | 71.23 | 7.24 | 3.443 | 0.037* |
| Two parallel canals | 8 | 69.66 | 8.52 | |||
| Y-type canal | 40 | 67.57 | 8.42 | |||
| Incisive foramina diameter (mm) | Single canal | 33 | 4.15 | 0.48 | 5.328 | 0.002* |
| Two parallel canals | 8 | 3.78 | 1.10 | |||
| Y-type canal | 40 | 4.28 | 0.74 | |||
| Nasal foramina diameter (mm) | Single canal | 33 | 3.42 | 0.62 | 1.769 | 0.271 |
| Two parallel canals | 8 | 3.49 | 0.18 | |||
| Y-type canal | 40 | 3.09 | 0.58 | |||
| BBP length (mm) | Single canal | 33 | 18.12 | 4.13 | 0.983 | 0.371 |
| Two parallel canals | 8 | 16.45 | 4.46 | |||
| Y-type canal | 40 | 16.79 | 3.76 | |||
| BBP width (mm) | Single canal | 33 | 6.04 | 1.34 | 0.846 | 0.416 |
| Two parallel canals | 8 | 5.89 | 1.68 | |||
| Y-type canal | 40 | 5.20 | 1.28 |
* Statistically significant differences (p ≤ 0.05)
Regarding axial slice, number of oral/nasal foramina of the NC had no significant influence on NC length, NC angle, incisive and nasal foramina diameter, BBP length and width (Table 6).
Table 6.
Effect of number of oral/nasal foramina of the canal on NC and BBP dimensions
| Parameters | Axial classification | N | Mean | SD | F | p |
|---|---|---|---|---|---|---|
| Age | 1–1 | 19 | 47.24 | 11.12 | 2.158 | 0.091 |
| 1–(2–5) | 49 | 39.93 | 15.18 | |||
| 2–(2–4) | 8 | 45.68 | 11.07 | |||
| 3–(1 and 3) | 5 | 44.12 | 9.65 | |||
| NC length (mm) | 1–1 | 19 | 10.31 | 2.17 | 3.441 | 0.018* |
| 1–(2–5) | 49 | 10.98 | 1.12 | |||
| 2–(2–4) | 8 | 11.16 | 3.17 | |||
| 3–(1 and 3) | 5 | 11.47 | 2.78 | |||
| Nasopalatine angle (°) | 1–1 | 19 | 71.23 | 6.78 | 1.882 | 0.116 |
| 1–(2–5) | 49 | 69.47 | 8.22 | |||
| 2–(2–4) | 8 | 71.11 | 7.12 | |||
| 3–(1 and 3) | 5 | 65.28 | 8.12 | |||
| Incisive foramina diameter (mm) | 1–1 | 19 | 3.85 | 0.48 | 3.468 | 0.237 |
| 1–(2–5) | 49 | 3.38 | 0.79 | |||
| 2–(2–4) | 8 | 4.21 | 0.44 | |||
| 3–(1 and 3) | 5 | 3.97 | 1.10 | |||
| Nasal foramina diameter (mm) | 1–1 | 19 | 3.42 | 0.62 | 2.689 | 0.463 |
| 1–(2–5) | 49 | 3.49 | 0.28 | |||
| 2–(2–4) | 8 | 3.09 | 0.48 | |||
| 3–(1 and 3) | 5 | 3.23 | 0.65 | |||
| BBP length (mm) | 1–1 | 19 | 18.02 | 2.23 | 0.434 | 0.716 |
| 1–(2–5) | 49 | 19.23 | 3.26 | |||
| 2–(2–4) | 8 | 16.19 | 5.22 | |||
| 3–(1 and 3) | 5 | 14.43 | 4.66 | |||
| BBP width (mm) | 1–1 | 19 | 5.20 | 0.87 | 1.110 | 0.343 |
| 1–(2–5) | 49 | 6.04 | 1.84 | |||
| 2–(2–4) | 8 | 5.89 | 0.98 | |||
| 3–(1 and 3) | 5 | 5.71 | 1.28 |
* Statistically significant differences (p ≤ 0.05)
The current study clearly indicates that there exists a high variability in NC morphology and that gender has an influence on the dimensions and morphology of the NC and BBP. Male patients generally exhibited higher mean values as compared to female patients. The age of the patients had a significant influence only on the length of the NC, with the mean values generally decreasing with increasing age.
Based on the results of the current study, CBCT imaging is a vital tool in determining the dimensions and morphology of the NC before dental implant surgery, especially when one or both of the maxillary central incisors have been lost over a longer period of time.
Discussion
Implant therapy in the maxillary central incisor region should always be preceded by careful radiographic analysis as there is a close anatomical approximation between the NC and the roots of these teeth. However, there is a scarcity of data regarding the typical morphology, dimensions and anatomical variations of the NC [3]. Also, the clinical implications and risks of damaging the NC and its neurovascular structures have not been adequately addressed in the literature.
Several invasive procedures have been presented for rehabilitation of the atrophied maxilla like guided bone regeneration and subsequent implant placement [17], application of a block graft, enucleation and placement of dental implants directly into the NC [18]. Several authors have presented different surgical techniques to manage perforation of the NC following implant osteotomies [17, 19, 20].
CT scans [3, 9, 15], micro CT images [16] or high-resolution magnetic resonance imaging [7] have been used in the past to analyze the macro and microanatomy of the maxillary anterior region and also the course of the nasopalatine nerve and its accompanying vessels. In the present study, the maxillary anterior region was evaluated using CBCT for cross-sectional imaging. CBCT administers less radiation dose to the patients as compared to the conventional CT scans and also has many other advantages [21]. CBCT is gradually replacing CT scans for the purpose of diagnosis and evaluation of the bone and neurovascular structures in the maxillary anterior region.
In the present study, gender significantly influences the NC and BBP dimensions with male patients reporting higher values as compared to females. These findings were in accordance with a study conducted by Mardinger et al. [15].
With respect to three-dimensional analysis in sagittal slice, a cylindrical canal was diagnosed in 39 cases, leaving almost 50 % of the cases with hourglass-like or funnel-like variations. These results were similar to the findings of Bornstein et al. [10], Mardinger et al. [15] and Tözüm et al. [22]. Almost significant differences were found in terms of age between hourglass-like and funnel-like shapes.
With respect to analysis from the coronal aspect, Y-type canal was observed more frequently followed by single canal and two parallel canals. Other studies [10, 16] in the past have observed single canal to be the most frequent.
For the purpose of three dimensional analysis from the axial aspect, we established the following groups: (1–1), [1–(2–5)], [2–(2–4)] and [3–(1 and 3)]. The most frequent axial group observed in our study was [1–(2–5)], with the (1–2) group accounting for 75.6 % of the 49 cases. However, Liang et al. [9] observed (1–1) in 44 % of cases, followed by (1–2) in 39 % of cases.
Bornstein et al. [10] reported a mean NC length of 10.99 mm, which is similar to the findings of the present study, in which the mean value was 11.13 mm. The greatest NC length was observed in cylindrical canals, single canals and group (1–1) from sagittal, coronal and axial aspects respectively.
The mean value observed for nasopalatine angle was similar to that reported by Liang et al. [9]. Liang et al. [9] used horizontal plate of palate as a reference point while we used the nasal floor, but both these planes are parallel and hence comparisons can be drawn. Song et al. [16] evaluated the angle formed by the vertical line perpendicular to nasal floor and the NC, which is complementary to the nasopalatine angle used in the current study. When Song et al. [16] obtained a value of 0°, it indicated that there was no separation between NC and the vertical line and this corresponds to a 90° angle in our study. Hence the angle values observed by Song et al. [16] are similar to the ones reported in our study.
In their study, Song et al. [16] reported that the incisive foramina always comprised of only a single foramen and the foramina of Stenson always had two openings. However, these findings are in contradiction with our study, which sometimes observed two parallel canals. In fact, our study reported 2 % of cases that had three openings at the incisive foramina, which coalesced to form one foramen of Stenson or continued to three [3–(1 and 3)]. Recent studies by von Arx et al. [23] and Neves et al. [24] are in accordance with our findings. Von Arx et al. [23] reported 27.8 % of accessory canals, confirming the presence of bone channels within the anterior maxilla. Also, Neves et al. [24] reported a case of a complete additional NC, in which each channel extended from independent foramina of Stenson to independent incisive foramens.
The present study showed BBP dimensions similar to those reported by Tözüm et al. [22] and Bornstein et al. [10]. Also, in terms of gender, our findings are similar to these authors [10], where male patients presented greater values in both, BBP height and width dimensions.
A thorough analysis of the NC and BBP dimensions with CBCT images is necessary in order to obtain the best prognosis for any surgical treatment in the maxillary anterior region.
Most nerves, arteries and veins contained in the NC nourish the premaxillary region. However, in this study analysis from the axial aspect shows that the NC can be formed by several canaliculi, as reflected by the different axial groups. Therefore, it is important to assess the content of NC to avoid any neurovascular or anesthetic complications. Placement and angulation of dental implants in the maxillary central incisor region should be preceded by careful analysis of the nasopalatine angle.
Conclusion
In terms of esthetic and functional rehabilitation, the maxillary anterior region is an area with a significant clinical relevance. The current study demonstrates variability of the NC in terms of shape and number; hence, a thorough CBCT analysis is highly recommended for better surgical outcomes and to reduce the post-operative complications in implant dentistry.
Abbreviations
- NC
Nasopalatine canal
- BBP
Buccal bone plate
- CBCT
Cone beam computed tomography
- ANOVA
Analysis of variance
- MLRM
Multivariant linear regression model
Compliance with Ethical Standards
Conflict of interest
None.
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