Assessment of accessory canals of the canalis sinuosus: a study of 1000 cone beam computed tomography examinations

[Anatomy and function of the canalis sinuosus and its injury prevention and treatment strategies in implant surgery]

The canalis sinuosus, a canal containing the anterior superior alveolar nerve bundle, originates from the infraorbital canal and extends along the maxillary sinus and nasal cavity edges to the anterior maxilla. It was once regarded as an anatomical variation. However, with the widespread application of cone beam computed tomography (CBCT), the detection rate of canalis sinuosus in the population has increased. The canalis sinuosus exhibits diverse courses, branching into multiple accessory canals and terminating at the nasal floor or the anterior tooth region, with the majority traversing the palatal side of the central incisor. The anterior superior alveolar nerve bundle within the canalis sinuosus not only innervates and nourishes the maxillary anterior teeth and the corresponding soft tissues, and the maxillary sinus mucosa, but also relates to the nasal septum, lateral nasal wall, and parts of the palatal mucosa. To minimize surgical complications, strategies for preventing and treating canalis sinuosus injuries need to be investigated. Preoperatively, CBCT is used to identify the canalis sinuosus and to virtually design implant placement at a distance of more than 2 mm from the canalis sinuosus. Intraoperatively, assessing bleeding and patient comfort, complemented by precision surgical techniques such as the use of implant surgical guide plates. Postoperatively, CBCT is used to examine the relationship between the implant and the canalis sinuosus, and treatment of canalis sinuosus injuries can be tailored based on the patient's symptoms. This review summarizes the detection of canalis sinuosus in the population, its anatomical characteristics, and the physiological functions in the anterior maxilla, and discusses strategies for avoiding canalis sinuosus injuries during implant surgery, thereby enhancing clinical awareness and providing references for clinical decision-making.

Immediate implant placement in the premolar maxillary area: a cone-beam computed tomography study

PURPOSE

This research aimed to investigate potential factors associated with the risk of perforation of the labial bone plate, nasal floor, or maxillary sinus floor during immediate implant placement (IIP) in the maxillary premolar area, utilizing a cone-beam computed tomography (CBCT) virtual study.

METHODS

CBCT exams from 179 eligible participants, encompassing 716 teeth, were included. Implants were virtually positioned in 2 orientations: along the long axis of the tooth (the prosthetically-driven position) and in an optimal position relative to adjacent anatomical structures (the bone-driven position). Binary logistic regression analysis was employed to assess potential associations between perforation or invasion and various covariates, including sex, age, tooth region, the distance from the tooth apex to the nasal floor or maxillary sinus floor, the angle between the prosthetically- and bone-driven positions (implant-line A angle [ILAA]), and the labial concavity angle (LCA).

RESULTS

The mean ILAA was 18.3°±8.0°, and the angle was significantly larger for the second premolar compared to the first premolar. The mean minimum implant length was 13.0±2.1 mm, with a bone anchorage of 4 mm. The incidence of perforation was 84.1% for the prosthetically-driven position and 40.5% for the bone-driven position. Factors associated with a higher risk of cortical bone wall perforation or invasion of the 2-mm safety margin from surrounding anatomical structures (in the bone-driven position) included female sex, older age, shorter distance from the tooth apex to the nasal cavity/maxillary sinus, and smaller LCA.

CONCLUSIONS

A high prevalence of cortical bone wall perforation or invasion of the 2-mm safety margin is anticipated when performing IIP in the maxillary premolar region.

Anatomical Factors of the Anterior and Posterior Maxilla Affecting Immediate Implant Placement Based on Cone Beam Computed Tomography Analysis: A Narrative Review

BACKGROUND

The aim of this narrative review was to provide insights into the influence of the morphological characteristics of the anatomical structures of the upper jaw based on cone beam computed tomography (CBCT) analysis on the immediate implant placement in this region.

MATERIAL AND METHODS

To conduct this research, we used many electronic databases, and the resulting papers were chosen and analyzed. From the clinical point of view, the region of the anterior maxilla is specific and can be difficult for immediate implant placement.

FINDINGS

Anatomical structures in the anterior maxilla, such as the nasopalatine canal and accessory canals, may limit and influence the implant therapy outcome. In addition to the aforementioned region, immediate implant placement in the posterior maxilla may be challenging for clinicians, especially in prosthetic-driven immediate implant placement procedures. Data presented within the recently published materials summarize the investigations performed in order to achieve more reliable indicators that may make more accurate decisions for clinicians.

CONCLUSION

The possibility for immediate implant placement may be affected by the NPC shape in the anterior maxilla, while the presence of ACs may increase the incidence of immediate implant placement complications. The variations in IRS characteristics may be considered important criteria for choosing the implant properties required for successful immediate implant placement.

Quantitative evaluation of the canalis sinuosus relative to adjacent structures in cone-beam computed tomography images

Background

Careful anatomical investigation of canalis sinuosus (CS) is essential to prevent damage to blood vessels and nerves in this area during surgical procedures, such as placing dental implants in the anterior maxillary region. This study investigated the relationship and distance between the CS and its adjacent structures.

Methods

A total of 400 cone-beam computed tomography (CBCT) images of Iranian adults aged 20-86 years were included in this retrospective study. Two observers assessed all the images twice with a time interval of one month. The closest tooth to the CS, its position relative to the CS, and distance measurements of the CS from adjacent structures were determined.

Results

CS was found in 10.5% of all images. The mean diameter of the canal was 1.06±0.29 mm, which was not significantly different between the age groups, right and left sides, or genders. The most common location of CS was mid-position relative to the upper lateral incisors. In linear measurements, only the distance from the CS to the buccal cortical plate and perpendicular to the nasopalatine canal exhibited a significant difference between the two sexes, with no significant difference between the right and left sides.

Conclusion

CS location was significantly more palato-lateral in males. There was no significant difference in the prevalence between the two sexes.

Retrospective evaluation and descriptive analysis of the prevalence of anatomical structures and variations in CBCT images before dental implant planning in a group Turkish population, part I

PURPOSE

The aim of this study is to emphasize the importance of using cone-beam computed-tomography in order to determine the anatomical structures and their variations before the treatment in patients who apply to the dentist clinic for implant treatment.

METHODS

In the study, CBCT images of 500 adult patients (240 female and 260 male), aged between 21 and 82 years, who applied for implant treatment due to missing teeth, were retrospectively analyzed. Anatomical structures and variations such as nasopalatine canal(NPC), canalis sinuosus(CS), antral alveolar artery(AAA), were evaluated in multiplanar reformation(MPR) sections which are axial, sagittal and coronal can be viewed in consistence with each other.

RESULTS

The incidence of anatomical variation of CS in the right region was similar according to gender. The "Funnel" appearance of the NPC shape was found most common shape in both female and male patients (n = 89; 37.1% for females and n = 71; 27.3% for males).

CONCLUSION

CBCT has become the most popular 3D imaging method in dental practice especially for planning dental implants. Understanding the relationship with important anatomical structures before implant applications is crucial in dealing with potential complications that may arise afterward. Assessing significant anatomical structures by CBCT and taking precautions against possible risks facilitate the work of dentists during and after procedures.

A cone-beam computed tomography study of canalis sinuosus and its accessory canals in a South African population

OBJECTIVES

Canalis sinuosus (CS) is a clinically relevant structure in the anterior maxilla. The present study aimed to determine the prevalence and distribution of CS and its accessory canals (ACs) in the South African population and describe its anatomical variations.

METHODS

In total, 500 cone-beam computed tomography (CBCT) scans of the anterior maxilla were assessed for prevalence, sidedness, diameter, and distribution of CS. The frequency, number, diameter, configuration, and point of termination of ACs were also recorded. Statistical analysis was performed using analysis of variance, Kruskal-Wallis, chi-squared, and Fisher Exact tests with P < 0.05.

RESULTS

CS was present in most cases (99.6%), and commonly occurred bilaterally (98.8%). The mean diameter of CS was 1.08 mm (range: 0.50 mm-2.39 mm). Sex, population group, and age had no significant effect on the prevalence or sidedness of CS. Additionally, 535 ACs were observed in 58.8% of the sample, with 42.9% of ACs found bilaterally and 57.1% unilaterally. The mean diameter of the ACs was 0.86 mm on the left and 0.87 mm on the right (range; 0.50 mm-1.52 mm). The majority of ACs maintained a straight vertical configuration (72.3%). ACs most commonly terminated in the anterior palatal region of the maxilla (57.2%). No significant differences were found in any groups mentioned (P > 0.05).

CONCLUSIONS

A high prevalence of CS as well as ACs were observed in the sample population. Due to their clinical significance, surgical planning with the aid of high quality CBCT scans of the anterior maxilla is advisable.

Cone-beam computed tomography of accessory canals of the canalis sinuosus and analysis of the related risk factors

PURPOSE

Cone-beam computed tomography (CBCT) was used in this study for evaluating the diameter, prevalence, spatial location, and risk factors of the accessory canal (AC) of the canalis sinuosus.

METHODS

A comprehensive assessment of the incidence rate, diameter, three-dimensional (3D) spatial location, and direction of travel of AC was performed on 1003 CBCT images. The CBCT data were used to reconstruct a 3D model of the maxilla to determine the alveolar bone volume. The obtained data were further analyzed and processed.

RESULTS

AC was present in 50.1% of images. Male patients more frequently had ACs than female patients did (P < 0.01) and was positively correlated with the maxillary alveolar bone volume (P < 0.001, OR 1.532). Age or nasopalatine canal diameter were not significantly associated with the occurrence of AC (P > 0.05). Among the 502 patients with AC, AC was present on the left side, right side, and bilaterally in 189, 98, and 215, respectively. The maximum number of ACs observed per individual was eight. The average AC diameter was 0.89 ± 0.26 mm (minimum, 0.5 mm; maximum, 2.02 mm).

CONCLUSIONS

As the prevalence of AC and its trajectory display considerable variation among individuals, surgeons must consider the possibility of the presence of AC when devising surgical plans involving the anterior maxillary region.

Immediate implant placement in the anterior mandible: a cone beam computed tomography study

BACKGROUND

The placement of implants into the alveolar socket right after tooth extraction is called immediate implant placement (IIP). This approach has its particularities depending on which region of the jaws is involved. The anterior mandible region is peculiar due to the presence of mandibular incisors, which have the shortest roots among all permanent teeth.

PURPOSE

This study aimed to investigate the factors that could be associated with the risk of either cortical bone wall perforation or invasion of the 2 mm secure distance from the surrounding anatomical structures (defined as unsafe implant placement), with IIP in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study.

MATERIALS AND METHODS

CBCT exams from 239 eligible subjects were investigated. Implants were virtually placed in two distinct positions: prosthetically-driven (along the long axis of the existing tooth) and bone-driven position (according to the available bone and with regard to nearby anatomical structures). Correlation between several variables was tested, and binary logistic regression analysis in order to assess of the possible associations between covariates and unsafe placement was performed.

RESULTS

Safe placing implants was significantly higher for the bone-driven in comparison to the prosthetically-driven position (22.2% vs. 3.3%, respectively), and the 2-mm secure distance from anatomical structures was not possible to respect in the majority of cases (77.6% vs. 82.9%, respectively). Covariates associated with a higher risk of unsafe placement were tooth region (CI in relation to IL and CA), decrease of labial concavity angle (LCA), decrease of mandible basal bone height (MBBH), and decrease in mandibular bone thickness at the tooth apex level (MBT0).

CONCLUSION

The possibility of safely placing immediate implants in the anterior mandible is significantly higher for bone-driven than in prosthetically driven position. Presurgical virtual planning with CBCT is a great tool for minimizing the risk of implant unsafe placement with regards to the anatomical conditions in the mandible.

Assessment of canalis sinuosus, rare anatomical structure using cone-beam computed tomography: A prospective study

Objectives

This prospective study was performed with cone-beam computed tomography (CBCT) images for evaluating canalis sinuosus (CS), determine its location and diameter in relation to gender, age, and distances from important structures, including floor of nasal cavity, incisive foramen, edge of buccal cortical bone, and palatal cortical bone.

Material and Methods

The scans of 650 patients in total were included in this prospective analysis. Gender, age, the position of the CS, its presence or absence, diameter, and its location in reference to the adjacent teeth were the factors that were noted.

Results

The study had 301 female participants and 349 male participants, with a mean age of 42.19. Compared to females, males had a statistically higher frequency of CS. Higher age groups showed a higher presence of CS in comparison to the other age groups. The mean distances of these parameters on the left and right side did not differ significantly. Nonetheless, the distance on both sides between CS and nasal cavity floor for males and females, as well as the diameter and border of buccal-palatal cortical bone on the right side, were statistically significant different. On the left side, both genders demonstrated significance in buccal cortical margin and nasal cavity floor. IIn addition, in females, the diameter of the CS on the right and left sides differed on average. The associations between age and number of CS, CS diameter, and number of CS versus sex were all extremely weak. Overall, the study findings showed that CS is a typical anatomical feature in anterior maxillary region, irrespective of age, or gender.

Conclusion

The bony canal, CS is an obscure feature located in the frontal region of the maxilla. Surgeons can avoid complications by being aware of the auxiliary canals derived from this structure. With the use of CBCT, it is now feasible to examine the course of CS as it passes through the maxillary sinus's anterolateral wall with better radiological accuracy has already been documented.

Evaluation of the morphology of accessory canals of the canalis sinuosus via cone-beam computed tomography

PURPOSE

This study aims to assess the presence of accessory canal (AC) associated with canalis sinuous (CS), describing their frequency, lateralization, location, direction, and measurements in cone beam computed tomography (CBCT).

METHODS

Axial, coronal, sagittal, and cross-sectional reconstructions were analyzed in 248 CBCT images and the presence of CS, the presence of AC associated with CS, the lateralization, localization, and direction course of AC associated with CS was evaluated. CS diameter, AC diameter, the distance between the nasal cavity floor and CS (M1), CS and the buccal cortical bone (M2), and CS and the alveolar ridge (M3) were measured.

RESULTS

CS was detected in all CBCT scans as bilaterally. The prevalence of AC associated with CS was 35.5%. There was a significant difference between dental status anthe d presence of AC associated with CS. There was a significant difference between gender, dental status, and lateralization of AC associated with CS. While M1 was greater in male patients than females, M3 was greater in female patients. M2 and M3 were greater in younger patients.

CONCLUSION

Clinicians performing surgical procedures should keep in mind that anatomical variations of the vascular nerve bundle may be seen. M1, M2, and M3 measurements can be affected by gender, age, and dental status.

Neurological Risks During Implant Placement in the Anterior Maxilla and Mandible: A Literature Review

The placement of implants in the anterior maxillary and mandibular region requires esthetic proficiency and surgical finesse. It is important to consider the esthetic outcome while avoiding any type of nerve injury for the patient. In this literature review, anatomical structures of the anterior jaw were reviewed from a gross anatomical and radiographic interpretation. A discussion on the frequency of neurosensory complications for patients as a result of nerve damage in this region was evaluated. The purpose of this literature review was to educate the dental surgeon to consider the anterior jaw's neurological structures when performing procedures like implant surgery. The mandibular incisive canal (MIC) presents as an extension of the inferior alveolar canal that runs between the mental foramina. The MIC is a structure that is easily depicted in cone-beam computed tomography (CBCT) imaging and is present in most subjects in gross anatomical studies. The anterior loop of the mental nerve is another structure that is discussed in this paper. Although its structure is accurately depicted in CBCT images, its anatomical variations in patients can make implant treatment planning difficult. The maxilla contains 2 neurovascular structures that were discussed. First, the nasopalatine canal and its relation and impact on implant placement is evaluated. Case reports are reviewed that outline a prophylactic enucleation and bone grafting of the canal prior to implant placement. Second, the canalis sinuosus, which houses the anterior superior alveolar nerve, is of concern during implant placement in the lateral incisor region. Case reports involving nerve damage with follow-up are discussed.

Assessment of Canalis Sinuosus located in maxillary anterior region by using cone beam computed tomography: a retrospective study

Background

The aim of the study is to determine the distribution, location, diameter, and distance measurements of Canalis Sinusosus (CS) in relation with age and sex.

Methods

300 Cone-Beam Computed Tomography (CBCT) images were evaluated. The distance between CS and nasal cavity floor (NCF), buccal cortical bone margin (BCM), alveolar ridge (AR), respectively.The presence of CS smaller than 1 mm, and the diameter of CS larger than 1 mm were determined. Accessory canals (AC) were classified according to their position relative to the teeth.

Results

435 CS with a diameter of at least 1 mm and 142 CS < 1 mm were identified. The most frequently observed location of CS was the region of the right central incisors. The mean diameter of the canals ( CS ≥ 1) was 1.31 ± 0.19 on the right side and 1.29 ± 0.17 on the left side. No gender differences were found in canal diameter were observed (p > 0.05). There was no significant difference between men and women in the distance between CS and the NCF on the right side, and a significant difference was found in the distance of CS-NCF on the left side (p = 0.047). There were no significant differences between age groups in all parameters.

Conclusion

CBCT is a useful tool for identifying CS. Location and diameter of ACs could not be associated with a specific age group or sex.

Anatomical variations and accessory structures in the maxilla in relation to implantological procedures: an observational retrospective study of 212 cases using cone-bean computed tomography

PURPOSE

This study used cone-beam computed tomography (CBCT) to analyze the prevalence of several maxillary anatomical/accessory structures, as well as variations within each type, assessing how accurate diagnosis can minimize the risk of intraoperative complications during implantological procedures in the oral cavity.

METHODS

212 CBCT scans of the maxilla were analyzed, captured over a period of 18 months for surgical planning purposes. The prevalence of posterior superior alveolar arteries (PSAA), maxillary sinus septa (MSS), and branches of the canalis sinuosus (CS) were evaluated, as were the diameter and location of each anatomical structure in horizontal and vertical planes. P < 0.05 was considered statistically significant.

RESULTS

PSAAs were observed in 99.1% of cases, the intrasinus type being the most frequent; MSS were noted in 15.6% of the sample, mainly in the posterior region with sagittal orientation; CS branches were observed in 50% of patients, mainly in relation to the incisors and significantly more prevalent among males.

CONCLUSIONS

The use of CBCT significantly increases the possibility of clearly identifying these anatomical structures. The differences found between patients highlight the importance of carrying out an exhaustive radiological study of the individual to prevent complications, such as Schneiderian membrane perforation, neurovascular damage or bleeding during surgery.

Assessment of the knowledge of canalis sinuosus amongst dentists and dental students: An online-based cross-sectional study

INTRODUCTION

Canalis sinuosus (CS) is a neurovascular canal that corresponds to a small branch of the infraorbital canal. This study aimed at assessing the knowledge and detection performance of CS amongst dentists and dental students.

MATERIALS AND METHODS

Four-hundred and five dentists and dental students answered a questionnaire with three parts: 1. Socio-demographical; 2. Clinical cases with cone- beam computed tomography (CBCT) sections showing CS and 3. Previous knowledge about CS. The chi-squared test and Spearman's correlation test were used to compare results as appropriate. p-values below .05 were considered statistically significant.

RESULTS

Most participants did not identify CS in any CBCT. There was an association between the number of correct answers and dental specialties. Most individuals had not learned about CS previously. There was an association between past knowledge of CS and gender, highest academic degree, working environment, dental specialty and number of correct answers but not with age or experience in Dentistry.

CONCLUSION

This study suggests that most dentists are not aware about CS and do not know how to diagnose it. Previous knowledge about CS positively influenced its identification in CBCT.

Prevalence, Radiographic Features and Clinical Relevancy of Accessory Canals of the Canalis Sinuosus in Cypriot Population: A Retrospective Cone-Beam Computed Tomography (CBCT) Study

Background and Objectives: This retrospective study aims to evaluate the prevalence, radiographic features, and clinical relevancy of the accessory canals (AC) of the canalis sinuosus (CS) in patients referred for implant surgery. Materials and Methods: Cone-beam computed tomography (CBCT) images of the patients were collected and ACs were evaluated. Age, sex, bilateral distribution, localization, diameter, distance to the buccal cortical plate, distance to the crest of the alveolar ridge, terminal ending localization, and the presence of tooth or implant were recorded. Ninety-one patients who were eligible for this study were enrolled. Results: A total of 188 ACs were found in 91 patients with 86 bilateral and 5 unilateral distributions. The mean age of the patients was 45.39. All ACs had a terminal ending at the palatal cortical border. All parameters showed a non-normal distribution; thus, the Mann–Whitney U test was preferred. Bilateral AC distribution (p = 0.761), AC distance to the crest of the alveolar ridge (p = 0.614), AC distance to the buccal cortical plate (p = 0.105), and AC diameter (p = 0.423) showed no significant difference between females and males. According to our study, a CS might be an anatomical structure rather than an anatomical variation, as all patients had at least one AC of the CS. It can be inferred that the detection of ACs will be achievable once clinicians are aware of these structures with continuous regular anatomy reworks and with small voxel-sized CBCT devices. Conclusion: This study was conducted to find the features and prevalence of the CS, and it was found that the CS is an anatomical structure rather than an anatomical variation. This argument is in line with the information on the CS in Gray’s Anatomy, 42nd Edition. Impaired healings and complications of the CS can be avoided if clinicians follow the American Academy of Oral and Maxillofacial Radiology guidelines regarding pre-operative implant examination. Otherwise, avertible complications may cause significant impairments in quality of life.

Prevalence of canalis sinuosus and accessory canals of canalis sinuosus on cone beam computed tomography: a systematic review and meta-analysis

The aim of this systematic review was to determine the prevalence of the canalis sinuosus (CS) and accessory canals of the canalis sinuosus (ACCS) as identified on cone beam computed tomography (CBCT). Online searches were conducted in the MEDLINE (via PubMed), Scopus, LILACS, Cochrane CENTRAL, Web of Science, and SIGLE (via OpenGrey) databases. Primary studies that determined the prevalence of canalis sinuosus and/or its anatomical variations using CBCT were included. The risk of bias assessment was performed using the AQUA tool. The quality effects model using double arcsine transformation was used for the meta-analysis of prevalence. Heterogeneity, publication bias, and sensitivity analyses were performed. Of 3237 initial results, 17 papers were included for systematic review. The meta-analysis comprising 1994 patients showed a pooled prevalence of CS of 0.80 (95% confidence interval (CI) 0.51-0.99; P = 0.001; I² = 99%). Publication bias analysis revealed minor asymmetry (LFK index 1.84). The meta-analysis of 4605 patients showed a pooled prevalence of ACCS of 0.54 (95% CI 0.38-0.69; P = 0.001; I² = 99%). The sensitivity analysis showed a pooled prevalence of ACCS of 0.53 (95% CI 0.32-0.74; P = 0.001; I² = 99%) for studies with ≥ 1000 patients and 0.55 (95% CI 0.33-0.76; P = 0.001; I² = 98%) for studies with< 1000 patients. Canalis sinuosus showed a pooled prevalence of 0.80 and ACCS showed a pooled prevalence of 0.54; hence both should be considered as anatomical structures, which means that they are present in most people. Surgeons must be aware of the CS and ACCS on CBCT analysis during pre-surgical planning. PROSPERO REGISTRATION NUMBER: CRD42020154195.

The persistently sensitive or painful osseointegrated implant

OBJECTIVE

To determine why some implants can appear to be well osseointegrated with no signs of infection and yet can remain sensitive to percussion and painful and unable to tolerate the weight of a restoration.

STUDY DESIGN

Five patients were identified who between them had 7 implants that met the criteria of being persistently painful and sensitive to percussion while appearing to be well integrated and otherwise disease free. High-definition cone beam computed tomography scans were obtained for all patients. All patients had failed medical treatment.

RESULTS

The cone beam computed tomography scans showed radiolucent channels running from the nearest nerve trunk to the vicinity of the sensitive implants. These may represent neurovascular channels that originally supplied the teeth that were present at the site of the implants, and they may have terminal neuromas that neuromas may be irritated by the implant. In all cases removal of the offending implant caused either substantial or complete relief of discomfort.

CONCLUSION

The presence of terminal neuromas within the jaws may be responsible for persistent pain and sensitivity in an otherwise well-integrated and disease-free implant. Removal of the offending implant appears to be the only treatment.

Examination of Canalis Sinuosus using Cone Beam Computed Tomography in an Australian Population

BACKGROUND

Canalis sinuosus (CS) and its relationship with adjacent teeth is relevant for surgery in the anterior maxilla. Therefore, the aim of this study was to report the prevalence, characteristics, and variations of CS.

METHODS

Cone beam computed tomography (CBCT) scans of the anterior maxilla of 201 patients were reviewed. CS and the adjacent teeth were analysed by age, sex, and scan resolution, using analysis of variance, chi-squared and Fisher's exact tests. The widest and narrowest diameters of CS, and distance to tooth apex (DTA), were compared by quadrant, closest tooth, and location, and the associations were examined statistically with P < 0.05.

RESULTS

In the 201 scans, 412 CS were identified in 198 patients associated with 395 different teeth. Mean widest diameter was 1.08 ± 0.39 mm (range: 0.42-2.60 mm), while the narrowest diameter was 0.71 ± 0.26 mm (range: 0.25-1.59 mm), and mean DTA of 2.16 ±1.25 mm (range: 0-6.22 mm). CS detection was significantly lower with CBCT taken at resolution size of 0.250 voxels (P = 0.02).

CONCLUSIONS

CS was very common in the anterior maxilla. Clinicians would be well advised to identify this anatomical structure using CBCT before undertaking any surgery in the anterior maxilla. © 2022 Australian Dental Association.

Immediate Implant Placement in the Maxillary Aesthetic Zone: A Cone Beam Computed Tomography Study

This study aimed to investigate the factors that could be associated with the risk of labial cortical bone wall perforation with immediate implant placement (IIP) in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study. CBCT exams from 126 qualified subjects (756 teeth) were included. Implants were virtually positioned in two different positions: in the long axis of the tooth (prosthetically-driven position) and in an ideal position in relation to adjacent anatomical structures (bone-driven position). Two different implant diameters were planned for each tooth position, namely, 3.75 and 4.3 mm for central incisors and canines, and 3.0 and 3.3 mm for lateral incisors. The incidence of perforation was nearly 80% and 5% for prosthetically- and bone-driven position, respectively. Factors associated with a higher risk of cortical bone wall perforation (bone-driven position), according to logistic regression analysis, were women, wider implants, Sagittal Root Position class IV, and decrease of the labial concavity angle. Perforation of the labial cortical bone wall can be greatly minimized when the implant is placed in a bone-driven position compared to a prosthetically-driven position. It is important to preoperatively evaluate the morphological features of the implant site for risk assessment and to individualize the treatment plan.

Morphological and Morphometric Characteristics of Anterior Maxilla Accessory Canals and Relationship with Nasopalatine Canal Type-A CBCT Study

This study aimed to evaluate principal morphological and morphometric characteristics of accessory canals (ACs) of the anterior maxilla, as well as to analyze the relationship with nasopalatine canal (NPC) type. The results of our study showed that ACs were observed in almost 50% of participants. They were mostly presented bilaterally and in a curved shape, with a palatal foramen position. The morphometric characteristics of ACs were significantly influenced by NPC type. NPC type had the strongest impact on the distance between the NPC and AC, as well as on the distance between the AC and the facial aspect of buccal bone wall, in inferior parts of the alveolar ridge. On the other hand, the distance between the AC and central incisors was not significantly influenced by NPC shape in the lower region of the anterior maxilla. However, the participants with the banana-type of the NPC expressed the reduction in distance from the AC to the central incisor at the upper part in comparison with the subjects with the cylindrical-type of the NPC. On the basis of the results of this study, the simultaneous estimation of ACs and the NPC seems reasonable, as this approach may be useful in the prevention of complications which could occur during implant surgery interventions.

Evaluation of Location of Canalis Sinuosus in the Maxilla Using Cone Beam Computed Tomography

Background/Aim: The aim of this study is to evaluate the prevalence of a canalis sinuosus (CS) in the anterior maxilla.

Material and Methods: CBCT images of 673 patients (322 females and 351 males) were examined retrospectively with regard to age, gender, location of CS and relation to impacted canines. The age of the patients ranged from 14 to 82 years; the mean age of the female patients was 43.54 years and that of the males was 45.75 years. IBM SPSS 22 for Windows was used for statistical analysis of the results. Statistical comparisons between two categorical variables were conducted using chi-square tests. Significance was set at (p< 0.05).

Results: It was observed that 8.17% of the patients in this study exhibited accessory canals (AC) of CS (n= 55). There was no significant difference in CS prevalence between ages, age groups, and location in our study (p> 0.5). There was significant difference in CS prevalence between the genders (p< 0.5).

Conclusions: It is important to take into consideration the presence of AC of the CS during surgical procedures in the anterior maxilla. It was also found that CBCT is more helpful than other techniques in detecting accessory canals in the region of interest.

Management of a neurological lesion involving Canalis Sinuosus: A case report

This case report describes the management of a lesion involving the Canalis Sinuosus (CS), that is a bone channel originating from the infraorbital canal below the orbital margin and posterior to the infraorbital foramen and coursing in an anterolateral direction to the anterior wall of the nasal cavity. A female patient, 62y, ASA 1, wearing full mobile dentures, came to our clinic asking for upper jaw rehabilitation. Due to a severe bone atrophy, a graft procedure was performed and the placement of eight implants was planned. One week after implants were positioned, the patient referred pain in the upper right central incisor region, that was compatible with a normal post-operative healing. After 15 days, since the symptoms worsened and became localized and persistent, a more detailed CBCT analysis was carried out. The images demonstrated that a CS on the right side was compressed by the apex of the implant in position #11. The implant was replaced with a shorter one and adequate pharmacological therapy was prescribed. All the symptoms completely disappeared after 30 days.

Invasion of the canalis sinuosus by dental implants: A report of 3 cases

The canalis sinuosus (CS) and its accessory canals (ACs) are anatomical structures in the anterior maxilla. These structures are often neglected when planning implant surgery because their clinical significance is still not well-defined. After a retrospective evaluation of 194 patients rehabilitated with dental implants in the anterior maxilla, 3 patients were identified who presented unexpected chronic neurosensory disturbances without any clinical signs supportive of implant failure. Tomographic assessment using cone-beam computed tomography (CBCT) revealed the invasion of the CS and ACs by dental implants, which appeared to explain the patients' symptoms. The purpose of this report was to familiarize practicing dentists and specialists with the CS and its ACs. Unanticipated neurosensory symptoms after implant placement in the anterior maxilla justify the use of CBCT to rule out an injury to this neurovascular bundle.

Evaluation of canalis sinuosus in individuals with cleft lip and palate: a cross-sectional study using cone beam computed tomography

OBJECTIVE

To evaluate the canalis sinuosus (CS) in individuals with cleft lip and palate (CLP) and compare the findings with individual's NON-CLP using cone beam computed tomography (CBCT).

MATERIALS AND METHODS

The sample consisted of 100 CBCT exams of NON-CLP individuals (G1 group) and 200 of CLP individuals (G2 group). Recorded parameters included presence of CS, accessory canal to the CS, diameter greater than 1 mm, gender, age, localization in relation to teeth, and adjacent structures. Statistical tests were used to compare the findings between groups. A p value of < 0.05 was considered as significant.

RESULTS

A higher prevalence of accessory canal was found in the G2 (p < 0.001). The anteroposterior diameter of the right side CS in G2 was higher than G1 (p < 0.05), with average of 1.4 mm ± 0.4 mm. The accessory canal had a larger diameter in G2 than G1 (p < 0.05) with average of 1.3 mm ± 0.3 mm. Between UCLP, the CS presented the largest diameter for the side NON-CLP (p < 0.001). The accessory canal was more distant from the cortical buccal in G2 (P < 0.05). The dental region incidence of the accessory canal was molars and premolars for G2 and canines and incisors in G1.

CONCLUSION

Individuals with CLP show higher prevalence of accessory canal to the CS with larger diameters than NON-CLP. It is necessary that the professional make adequate planning prior to surgeries, using the CBCT, in order to avoid neurovascular lesions, since these individuals undergo several surgeries in the CS region.

Imaging Anatomy of the Jaw and Dentition with Cone Beam Computed Tomography

Knowledge of dental, maxillary, and mandibular anatomy and the use of correct nomenclature is critical in the evaluation of a mandibulofacial and/or maxillofacial imaging data set. The use of the correct diagnostic imaging tool tailored to the patient's needs is of equal importance. This article highlights imaging anatomy and cross-sectional imaging modalities mainly focusing on cone beam computed tomography of the mandibulofacial and maxillofacial region.

Cone beam computed tomography analysis of accessory canals of the canalis sinuosus: A prevalent but often overlooked anatomical variation in the anterior maxilla

STATEMENT OF PROBLEM

Accessory canals of the canalis sinuosus, a bony canal carrying the anterior superior alveolar nerve and vessels, can often be present but overlooked in the anterior maxilla. Dental implant placement in this area may damage neurovascular branches if this anatomic variation is not carefully identified, resulting in unexpected complications.

PURPOSE

The purpose of this retrospective study was to identify accessory canals of the canalis sinuosus and analyze their relationship to the terminal canalis sinuosus and anterior maxilla in Chinese patients to provide a warning for surgeons operating in the anterior maxilla.

MATERIAL AND METHODS

Cone beam computed tomography (CBCT) scans of 1007 Chinese patients were examined to identify the prevalence and size of accessory canals with at least 1.0-mm diameter. Axial position of this canal was classified referring to the nasal cavity and adjacent teeth. Its sagittal position was determined by the distance from the bifurcation site of canalis sinuosus to the buccal alveolar crest and the distance from the canal opening to the palatal alveolar crest. Diameter of the terminal canalis sinuosus, distance from the terminal canalis sinuosus to the buccal alveolar crest, and anterior maxillary volume were measured on all scans. Binary logistic regression and the Spearman rank correlation coefficient were used for prevalence and diameter analysis.

RESULTS

The prevalence of the accessory canal was 36.9%, positively correlated the anterior maxillary volume (OR 1.408) and negatively correlated with the distance from the terminal canalis sinuosus to the buccal alveolar crest (OR 0.921). Average diameter of such canal was 1.1 ±0.1 mm, significantly higher in men, positively correlated with the diameter of terminal canalis sinuosus (r_s=0.163) and the distance from the canal opening to the palatal alveolar crest (r_s=0.192). All accessory canals started below the buccal cortical bone, 19.3 ±2.7 mm away from the buccal alveolar crest. There were 61.9% accessory canals opened between the central and the lateral incisors. Openings here and in the central incisor region were closer to the alveolar crest than that between the lateral incisor and the canine (P<.05).

CONCLUSIONS

Accessory canals of the canalis sinuosus have high prevalence in the anterior maxilla in a Chinese population. Large anterior maxillary volume has been demonstrated as a risk factor associated with the presence of such canals. The region between the central and the lateral incisors was a predominant location. Openings in this region were closer to the alveolar crest than those between the lateral incisor and the canine.

Canalis sinuosus: An Anatomic Repair that May Prevent Success of Dental Implants in Anterior Maxilla

Canalis sinuosus (CS) is a neurovascular canal that corresponds to a small branch of the infraorbital canal. It contains the anterior superior alveolar nerve and vessels, supplying the anterior maxilla. Despite having been described 81 years ago, CS is not recognized by many dental practitioners and may be the cause of unintended injuries during dental procedures. The aims of this study are to report a case of a patient who suffered pain due to exposure of the CS, to provide a comprehensive review of other CS cases that were challenging to diagnose, and to propose guidelines for preoperative examination of patients undergoing surgical procedures in the anterior maxilla. The review of the literature revealed six cases, in addition to the one presented here, of unintended or potential damage to CS. Five out of seven cases were related to dental implant placement and resulted in postoperative pain and/or paresthesia. The dental implant was removed in 4 out of the 5 cases. This study reinforces the importance of awareness of CS by dental practitioners and provides a protocol for the preoperative examination of the patient to prevent avoidable injuries to CS.

Extra-Long Nasal Wall-Directed Dental Implants for Maxillary Complete Arch Immediate Function: A Pilot Study

Immediate loading of maxillary denture prostheses in the context of severe bone atrophy is complicated by posterior implant placement, sometimes requiring a complex surgical approach as zygomatic or pterygoid implants. To overcome this complexity, the authors developed an extra-long (20-24 mm) 24-degree angulated platform. It was tested on 33 patients, with 24 patients immediately loaded (72.7%) for a total of 115 implants (46% nasal). All delayed loading implants osseointegrated. Eight bilateral and six unilateral sinus grafts were performed. There were no complications during the follow-up period.

Assesment of accessory branches of canalis sinuosus on CBCT images

Background

The aim of this study is to describe the presence, to reveal the frequency and characteristics of accessory canals (ACs) of the canalis sinuosus (CS) by cone beam computed tomography (CBCT).

Material and Methods

A total of 326 CBCT examinations were scanned retrospectively. The anatomical views were evaluated on sagittal, axial, coronal and cross sectional imaging. The following parameters were recorded: age, sex, presence or absence of ACs, location in relation to the adjacent teeth and distance to the nasal cavity floor (NCF), alveolar ridge crest (ARC) and buccal cortical bone (BCB), and incisive canal. All the collected data were statistically analyzed.

Results

113 patients (34,7%); presented ACs in total 214 foramina of the sample. There were no statistically significant changes in the presence of ACs regarding age groups excluding 80-89 years. But there is a statistically significant difference regarding the frequency of ACs and the gender. The prevalence for male patients was higher than female patients. Curved-shape configuration of CS prevalence is found as 69,15%. The prevalence of vertical tracing is 26,16% and Y-shape configuration of CS prevalence is 4,67%. Diameter of the foramens of the CS branches was 1.30 mm. The mean distance of the AC to the NCF, BCB, and ARC were found 13,83 mm, 6,60 mm and 5,32 mm, respectively.

Conclusions

In the anterior palatal region, ACs are mostly related to CS’s branches. So; knowing the course of CS branches in surgical planning and radiographic evaluations in this region is extremely important for preventing complications and avoiding misdiagnosis.

Key words:Anterior superior alveolar nerve, canalis sinuosus, maxilla.

Visualization features of canalis sinuosus with cone beam computed tomography

Introduction

One of the key stages of evaluating an edentulous ridge prior to dental implant placement is the analysis of neighboring anatomical structures such as canalis sinuosus (CS) with cone-beam computed tomography (CBCT). CBCT visualization has its own features, such as the change of slice thickness. The aim of the study was to analyze CS prevalence in relation to the slice thickness and CS diameter according to CBCT scans.

Materials and Methods

In total, 100 CBCT scans of 39 males and 61 females in the age span of 46 to 81 years were retrospectively studied. Terminal alveolar part of CS was analyzed in Ez3D2009 (Vatech) software on panoramic and cross-sectional views with 0.5 mm, 1 mm, 3 mm, and 10 mm slice thicknesses. The prevalence was documented with regard to the diameter and slice thickness and was statistically compared in age and gender groups.

Results

This CBCT study demonstrated 55.5% CS prevalence. There was no statistically significant difference in presence between age and gender groups regarding diameter as well as within different slice thickness. The study also showed the importance of the slice thickness choice for CS visualization: the best visualization was reached with 0.5 mm and 1 mm slice thicknesses. Visualization with 0.5 mm and 1 mm slice thicknesses was absolutely the same (55.5%). General CS prevalence with a 10 mm slice thickness (16.5%) was significantly lower (P < 0.05) than the prevalence with a 3 mm slice thickness (20.5%). The correlation between the slice thickness and a diameter more than 1.5 mm in size was not found.

Conclusion

CBCT analysis showed that the highest CS prevalence was detected with the use of 0.5/1 mm slice thickness. As well, the higher CS diameter, the better is its visualization.

Canalis Sinuosus Damage after Immediate Dental Implant Placement in the Esthetic Zone

Dental implant failure in the anterior maxilla can be caused by the range of the features. One of them is neighboring neurovascular structure damage, such as the canalis sinuosus (CS), that carries the superior anterior alveolar nerve. The aim of the report is to demonstrate clinical symptomatology and radiographic signs of CS damage in a 45-year-old female patient who underwent upper left lateral incisor extraction and immediate implant placement and implant removal in 16 days secondary to pain and paresthesia in the maxillary left region.

Radiological and Morphometric Features of Canalis Sinuosus in Russian Population: Cone-Beam Computed Tomography Study

Introduction

Cone-beam computed tomography (CBCT) is considered to be the most informative radiographic method for pre- and postoperative analysis of the maxillary anatomy and for avoiding further complication. Canalis sinuosus is one of such structures that damage can go along with bleeding and neurological symptomatology. The aim of the study was to investigate radiological and morphometric features of the canalis sinuosus in Russian population using CBCT technique.

Materials and Methods

150 CBCT scans of 61 males and 89 females aged from 24 to 80 years were retrospectively studied with different slice thickness and evaluated with regards to prevalence and diameter among age and gender groups in Russia.

Results

CS prevalence in this study was 67%, and CS was most frequently presented in the lateral incisor region (33.5%). Women showed statistically higher CS prevalence (p < 0.01) than the male group, and there was no statistically significant difference observed between occurrence and localization of CS and age groups.

Conclusion

CBCT examination demonstrated good diagnostic efficiency in CS visualization, and the CS may have variations on its location and prevalence with statistically significant differences between the gender group and without significant differences among age groups and can depend on the population.

Canalis sinuosus: anatomical variation or structure?

PURPOSE

The main goal of the present study was to verify the presence, spatial location, the end of the canalis sinuosus (CS) trajectory and size of CS using cone beam computed tomography (CBCT) to characterise it as either a structure or an anatomical variation.

METHODS

A trained examiner specialist in dental radiology and imagenology selected 200 CBCT images of the maxilla from 107 (53.5%) female and 93 (46.5%) male individuals aged between 18 and 85 years.

RESULTS

A total of 133 (66.5%) patients had CS, being 61 (45.86%) unilateral and 72 (54.14%) bilateral. A higher frequency of CS was observed in males (P < 0.05) and no relationship was found between its presence and age. The end of the CS trajectory was more frequent in the regions of central incisor (n = 91; 44.39%), followed by lateral incisor (n = 45; 21.95%) and canine (n = 29; 14.15%). In our sample, the majority of these canals had a diameter of up to 1 mm (n = 198/205; 96.6%). No statistically significant relationship between diameter and the end of the CS trajectory, with location (i.e. bilateral or unilateral) was found. Gender and age had no influence on diameter, spatial location and the end of the CS trajectory (P > 0.05%).

CONCLUSION

As CS was frequently found in our sample, it can be considered an anatomical structure, and as such, it is fundamental that the dentist requests a CBCT examination before performing any invasive procedure in the maxillary region to preserve this important structure.

Canalis sinuosus: a systematic review of the literature

OBJECTIVE

The aim of this study was to conduct a systematic review of the frequency, location, diameter, variations in course, relationship to the course of the anterior superior alveolar nerve (ASAN), patient age and gender, and surgical implications of canalis sinuosus (CS), identified through imaging examinations, macerated skulls, or cadaver heads.

STUDY DESIGN

Medline, Scopus, and Web of Science databases were searched, and the retrieved articles were analyzed by 2 reviewers. The articles were selected by using well-established inclusion criteria. The Hawker scale was used for quality analysis. A kappa test was used to measure interobserver agreement.

RESULT

The search identified 70 articles, of which 11 were selected for extraction and data analysis. Most studies consisted of cone beam computed tomography examinations of the location, diameter, and variable presence of accessory channels (ACs) in the CS. In total, 90.9% of the studies were of high or moderate quality.

CONCLUSIONS

The CS may present variations in its course, location, and diameter. It involves ASAN and a extension to the anterior palate region, the ACs. No statistically significant differences with regard to age or gender were discovered in the studies. Most articles report the relevance of the CS identification in surgical procedures close to the canal and emphasize the importance of awareness of the variable appearance of the CS.

Cone-beam tomographic analysis of canalis sinuosus accessory intraosseous canals in the maxilla

The aim of this study was to assess the frequency, location and width of accessory canals (AC) of canalis sinuosus (CS) using cone beam computed tomography and compare our findings with recent literature. Additionally, intraosseous canals (IOC) in the sinus wall other than the CS were noted. A retrospective analysis of 219 scans from our university department was conducted. The registered parameters were age, sex, location and width of canals. Group A consisted of 201 (85 males and 116 females) adults ranged from 19 to 99 years of age (mean age = 47.5 years). A total of 136 patients (67.6%) presented at least 1 AC, of which 55 cases showed a foramen width greater than 1 mm (27.4%). Group B had a sample size of 18 adolescents (7 males and 11 females) with a range of age from 7 to 18 years (mean age = 15.8 years). Eight cases (44.4%) presented at least one AC, of which only 3 had a foramen width greater than 1 mm (3.6%). ACs were found to occur predominantly at central incisors region (Group A) and the left lateral incisor and canine as well as the central incisors regions (Group B). Adolescents showed a lower prevalence of accessory canals compared to adults. These findings supplement earlier reports on the anatomical variations of the intraosseous vessel and nerve conduits of the maxilla. Surgical interventions in this area can be planned more precisely, taking into account the three-dimensional imaging, thus possibly protecting these sensitive structures.

Combined anatomical variations: The mylohyoid bridge, retromolar canal and accessory palatine canals branched from the canalis sinuosus

The study of anatomical variations is important not only for collecting anthropometric data, but also for improving clinical protocols and understanding why a particular clinical procedure sometimes does not yield the expected results. We report the case of a 74 year-old patient, in which we observed combined anatomical variants of the mandible and maxillary bone. One of these was the unilateral mylohyoid bridge (MB) of the uncommon, lingular type. This MB extended posteriorly to the spine of Spix, over the sulcus colli behind the spine. It thus formed a common mandibular canal (MC) which further divided into a retromolar canal and the MC proper. This combination of variants in the mandible has not, to our knowledge, previously been reported, at least in studies using cone beam computed tomography (CBCT). Additionally we found multiple accessory canals (ACs) deriving from the canalis sinuosus, which opened opposite to each frontal tooth, presumably carrying either dental fibers of the palatine nerves, or palatine fibers of the anterior superior alveolar nerve. Although the ACs in the anterior palate are well established anatomical variants, the MB appears in publications rather as an anthropological identifier. However, when present, it can impede anaesthesia of the lower teeth and thus deserves to be included in anatomical descriptions. The evaluation of patients in CBCT should observe the anatomical features on a case-by-case basis and it also provide data for studies of MB prevalence in large numbers of patients.

Dental Implant in the Canalis Sinuosus: A Case Report and Review of the Literature

The canalis sinuosus is a neurovascular canal, a branch of nerve of infraorbital canal, through which the anterior superior alveolar nerve passes and then leans medially in course between the nasal cavity and the maxillary sinus, reaching the premaxilla in the canine and incisor region. The purpose of this article is to report a case with the presence of canalis sinuosus, in order to alert and guide professionals and discuss the morphology of this anatomical variation avoiding trans- and postsurgical disorders in dental implants. A 51-year-old female was attended to in a radiology clinic, reporting paresthesia in the right upper lip region and painful symptomatology after the installation of an implant in the corresponding region. The case revealed the presence of canalis sinuosus in imaging exams. The knowledge of this anatomical variation is essential for professionals, because attention to this region prevents irreversible damage. Therefore, the use of imaging examinations is recommended during the planning stages and treatment and after surgery in patients undergoing surgery in this area.