Search

The purpose of this study was to compare the average distances from the root apices of the first molars, second molars, and second premolars to the mandibular canal according to sex in the Peruvian population using cone-beam computed tomography (CBCT). Eighty CBCT scans of Peruvian patients aged from 15-80 years were examined. After locating the mandibular canal, measurements of the vertical distances from the mandibular canal to the apices of the second premolars, as well as the first molars and second molars, were made. For the statistical analysis, Student’s t test was used for both paired and unpaired samples, with a significance level of p<0.05. On the right side, the second molar presented a mean distance of 3.99mm for males and 2.87mm for females, showing a significant difference (p<0.05). When compared bilaterally, no significant differences were found (p>0.05) between the distances from the apices of the second premolars and the first and second molars to the mandibular canal. However, for the second premolars and second molars on the left side, the values were higher, with averages of 5.52mm and 3.75mm, respectively.The mesial roots of the second molars were closer to the mandibular canal. In addition, women showed shorter distances than men., El propósito de este estudio fue comparar las distancias promedio desde los ápices radiculares de primeros molares, segundos molares y segundos premolares al canal mandibular según sexo en la población peruana mediante tomografía computarizada de haz cónico (TCHC). Se examinaron 80 tomografías CBCT de pacientes peruanos con edades comprendidas entre los 15 y 80 años. Luego de ubicar el canal mandibular, se realizaron mediciones de las distancias verticales desde el canal mandibular hasta el ápice de los segundos premolares mandibulares, así como de los primeros molares y segundos molares. Para el análisis estadístico se utilizó la prueba t de Student para muestras pareadas y no pareadas con un nivel de significación de p<0,05. En el lado derecho, el segundo molar presentó una distancia media de 3,99mm para hombres y 2,87mm para mujeres; exhibiendo una diferencia significativa (p<0.05). Al comparar bilateralmente, no se encontraron diferencias significativas (p>0.05) entre las distancias desde los ápices de los segundos premolares mandibulares y los primeros y segundos molares al canal mandibular. Sin embargo, para los segundos premolares y segundos molares en el lado izquierdo, los valores fueron más altos con un promedio de 5,52mm y 3,75mm, respectivamente.Las raíces mesiales de los segundos molares estaban más cerca del canal mandibular. Además, las mujeres mostraron distancias más cortas que los hombres.

This systematic review aims to identify the available semi-automatic and fully automatic algorithms for inferior alveolar canal localization as well as to present their diagnostic accuracy. Articles related to inferior alveolar nerve/canal localization using methods based on artificial intelligence (semi-automated and fully automated) were collected electronically from five different databases (PubMed, Medline, Web of Science, Cochrane, and Scopus). Two independent reviewers screened the titles and abstracts of the collected data, stored in EndnoteX7, against the inclusion criteria. Afterward, the included articles have been critically appraised to assess the quality of the studies using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Seven studies were included following the deduplication and screening against exclusion criteria of the 990 initially collected articles. In total, 1288 human cone-beam computed tomography (CBCT) scans were investigated for inferior alveolar canal localization using different algorithms and compared to the results obtained from manual tracing executed by experts in the field. The reported values for diagnostic accuracy of the used algorithms were extracted. A wide range of testing measures was implemented in the analyzed studies, while some of the expected indexes were still missing in the results. Future studies should consider the new artificial intelligence guidelines to ensure proper methodology, reporting, results, and validation.

Aim: To compare the accuracy of the panoramic radiography with cone-beam computed tomography (CBCT) scans in measuring the distances between root apexes and the adjacent anatomical structures including the maxillary sinus and the mandibular canal. Material and Methods: A total of 200 CBCT scans (100 maxillary and 100 mandibular) from patients who also had corresponding panoramic radiography were selected. Linear measurements (in mm) presenting centralized image were made between the apexes of the maxillary teeth and the inferior wall of the maxillary sinus, and between the apexes of the mandibular teeth and the superior border of the mandibular canal by using specific software for panoramic radiography and the measurements on the coronal sections in CBCT scans. Data were submitted to inferential statistical analysis and Student’s t-test for comparison between measurements. Results: CBCT scans were significantly more accurate than panoramic radiography to measure the distances between the apexes of the maxillary teeth and the inferior wall of the maxillary sinus (p<0.05) and between the apexes of the mandibular teeth and the superior border of the mandibular canal or mental foramen (p<0.05).Conclusion: CBCT scans present more accurate measurements than panoramic radiography., Objetivo: Comparar la precisión de la radiografía panorámica con las exploraciones de la tomografía computarizada dental de haz en cónico (CBCT) para medir las distancias entre los vértices radiculares y las estructuras anatómicas adyacentes, incluidos el seno maxilar y el canal mandibular. Material y Métodos: Se seleccionaron un total de 200 tomografías CBCT (100 maxilares y 100 mandibulares) de pacientes que además tenían la correspondiente radiografía panorámica. Se realizaron mediciones lineales (en mm) que presentaban imagen centralizada entre los ápices de los dientes maxilares y la pared inferior del seno maxilar, y entre los ápices de los dientes mandibulares y el borde superior del canal mandibular mediante software específico para radiografía panorámica. y las mediciones en las secciones coronales en escaneos CBCT. Los datos se sometieron a análisis estadístico inferencial y prueba t de Student para comparación entre mediciones. Resultados: Las exploraciones CBCT fueron significati-vamente más precisas que la radiografía panorámica para medir las distancias entre los ápices de los dientes maxilares y la pared inferior del seno maxilar (p<0,05) y entre los ápices de los dientes mandibulares y el borde superior de los dientes mandibulares. canal o agujero mentoniano (p<0.05). Conclusión: Las exploraciones CBCT presentan mediciones más precisas que la radiografía panorámica.

Introduction: The aim of this study was to assess the agreement between oral and maxillofacial radiologists (OMFR) and oral and maxillofacial surgeons (OMFS) for the detection of bifid mandibular canal (BMC) and accessory mental foramen (AMF) using cone-beam computed tomography (CBCT). Material and Methods: This retrospective study involved 22 examiners (11 OMFR and 11 OMFS) who independently assessed 30 CBCT volumes from patients (n = 60 hemi-mandibles) under preoperative radiographic evaluation for implant placement. The examiners scored the presence of BMC and AMF in each hemimandible. The interexaminer agreements were assessed using Fleiss' kappa statistics. Results: For intra-examiner agreement, 40% of the sample was reevaluated. The interexaminer agreement between OMFR and OMFS was slight (0.12) for the detection of BMC and fair (0.24) for AMF. The agreement among OMFR for detection of BMC was fair (0.22), and it was slight among OMFS (0.15). The agreement among OMFR for detection of AMF was substantial (0.61), and among OMFS it was fair (0.22). Agreements between OMFR and OMFS were slight for BMC and fair for AMF, independently of the years of experience. Intraexaminer agreement ranged from 60% to 90% among OMFR and from 55% to 90% among OMFS. Conclusion: A slight and a fair agreement between OMFR and OMFS was found for the detection of BMC and AMF, respectively. In general, OMFR obtained higher agreement among themselves, mainly for detection of AMF., Introducción: El objetivo de este estudio fue evaluar la con-cordancia entre los radiólogos orales y maxilofaciales (ROMF) y los cirujanos orales y maxilofaciales (COMF) para la detección del canal mandibular bífido (CMB) y el foramen mentoniano accesorio (FMA) mediante tomografía computarizada de haz cónico. CBCT). Material y Métodos: Este estudio retrospectivo involucró a 22 examinadores (11 ROMF y 11 COMF) que evaluaron de forma independiente 30 volúmenes CBCT de pacientes (n = 60 hemimandíbulas) bajo evaluación radiográfica preoperatoria para la colocación de implantes. Los examinadores puntu-aron la presencia de CMB y FMA en cada hemimandíbula. Los acuerdos entre examinadores se evaluaron utilizando las estadísticas kappa de Fleiss. Resultados: Por concordancia intraexaminador se reeva-luó el 40% de la muestra. El acuerdo entre examinadores entre ROMF y COMF fue ligero (0,12) para la detección de CMB y regular (0,24) para FMA. La concordancia entre ROMF para la detección de CMB fue regular (0,22) y leve entre COMF (0,15). El acuerdo entre ROMF para la detección de FMA fue sustancial (0,61), y entre COMF fue justo (0,22). Los acuerdos entre ROMF y COMF fueron leves para CMB y justos para FMA, independientemente de los años de experiencia. La concordancia entre examinadores varió del 60 % al 90 % entre ROMF y del 55 % al 90 % entre COMF. Conclusión: Se encontró un acuerdo leve y justo entre ROMF y COMF para la detección de CMB y FMA, respec-tivamente. En general, se obtuvo mayor acuerdo entre ROMF, principalmente para la detección de FMA.

Objectives: To evaluate the position and curvature of mandibular canal in relation to mandibular plane in horizontal (HG), average (AG) and vertical (VG) growth patterns.Methods: 100 lateral cephalograms were screened & analysed from amongst patient's recordsavailable in the institution. The growth pattern was assessed by FMA angle, Y-Axis, SN-Go-Gn angle and Jaraback's ratio, on the basis of these values, a sample was selected of 20 lateral cephalographs each in horizontal, average and vertical growth pattern. Rickett's Xi point was identified and mandibular canal was traced on each lateral cephalogram using Xi point which denotes the origin of mandibular canal. Distance between, Gonial point to Xi point, Mental foramen to mandibular plane (MFeM), Mandibular foramen to pterygoid vertical (XiePTV) and fromdeepest point on mandibular canal to mandibular plane (MceM) were measured to evaluate the position and curvature of mandibular canal in different growth patterns.Results: It was observed that, the distance from gonial point to mandibular foramen, mentalforamen to mandibular border, mandibular foramen to pterygoid vertical was increased inhorizontal growth pattern i.e., 22.05 mm ± 1.82, 15.12 mm ± 1.06, 57.20 mm ± 1.23, whereasit was reduced in vertical growth pattern i.e., 14.90 mm ± 1.55, 8.84 mm ± 1.41,47.95 mm ± 2.25 respectively. Depth of curvature of mandibular canal was increased inhorizontal growth pattern, 22.25 mm ± 4.89; while it was reduced in vertical growth patterni.e., 16.32 mm ± 1.18.Conclusions: The findings of this study showed that the position and curvature of themandibular canal reflect the outer morphology and growth pattern of the mandible.

Objectives: To evaluate the position and curvature of mandibular canal in relation to mandibular plane in horizontal (HG), average (AG) and vertical (VG) growth patterns.Methods: 100 lateral cephalograms were screened & analysed from amongst patient's recordsavailable in the institution. The growth pattern was assessed by FMA angle, Y-Axis, SN-Go-Gn angle and Jaraback's ratio, on the basis of these values, a sample was selected of 20 lateral cephalographs each in horizontal, average and vertical growth pattern. Rickett's Xi point was identified and mandibular canal was traced on each lateral cephalogram using Xi point which denotes the origin of mandibular canal. Distance between, Gonial point to Xi point, Mental foramen to mandibular plane (MFeM), Mandibular foramen to pterygoid vertical (XiePTV) and fromdeepest point on mandibular canal to mandibular plane (MceM) were measured to evaluate the position and curvature of mandibular canal in different growth patterns.Results: It was observed that, the distance from gonial point to mandibular foramen, mentalforamen to mandibular border, mandibular foramen to pterygoid vertical was increased inhorizontal growth pattern i.e., 22.05 mm ± 1.82, 15.12 mm ± 1.06, 57.20 mm ± 1.23, whereasit was reduced in vertical growth pattern i.e., 14.90 mm ± 1.55, 8.84 mm ± 1.41,47.95 mm ± 2.25 respectively. Depth of curvature of mandibular canal was increased inhorizontal growth pattern, 22.25 mm ± 4.89; while it was reduced in vertical growth patterni.e., 16.32 mm ± 1.18.Conclusions: The findings of this study showed that the position and curvature of themandibular canal reflect the outer morphology and growth pattern of the mandible.

Objectives: The aim of our study was to compare peri-implant bone loss at implants placed in alveolar sockets filled with a particulate allogenous bone graft (DFDBA 300-500 µm) and platelet concentrates versus at implants placed in the native bone. Materials and Methods: A retrospective clinical study was performed. A total of 84 patients were included with 247 implants for the restoration of mono and pluri-radicular teeth: 169 implants in native bone and 78 in socket-grafted bone. The peri-implant bone loss was measured by 2 independent operators at 6 and 12 months. Results: The overall mesial and distal peri-implant bone losses were 0.9 ± 0.7 mm and 0.9 ± 0.8 mm at 6 months, respectively, and 1 ± 0.65 mm and 1.2 ± 0.9 mm at 12 months, respectively. In the tested group, the bone loss was 0.8 ± 0.8 mm at 6 months and 1.2 ± 0.9 mm at 12 months. In the control group, the bone loss was 1.0 ± 0.7 mm at 6 months and 0.95 ± 0.6 mm at 12 months. There were no statistically significant differences in bone loss between the two groups. Taking both groups together, there were no statistically significant difference in bone loss between patients with or without histories of periodontitis, but there was a statistically significant difference in bone loss between the mandible and maxilla as well as between unitary and total edentations and between partially and total edentulous patients. Conclusion: At 6 and 12 months, the peri-implant bone loss in sockets preserved with DFDBA and platelet concentrates was similar to the peri-implant bone loss in native bone., SCOPUS: ar.j, info:eu-repo/semantics/published

In this paper, we explore the possibility of applying the anisotropic generalized Hough transform (AGHT) enhanced with a Gabor based time-frequency filtering (GTF) for the determination of the mandibular canal in digital dental panoramic radiographs. The proposed method is based on template matching us- ing the fact that the shape of the mandibular canal is usually the same, followed by a filtering of the accumulator space in the Gabor domain for a precise detection of the position. The proposed procedure consists of a detailed description of the shape of the canal in its canonical form and on preserving Gabor filtering information for sorting the hierarchy of location candidates after applying anisotropically the ex- traction algorithm. The experimental results show that the proposed procedure is robust to recognition under occlusion and under the presence of additional structures e.g. teeth, projection errors.

In this paper, we explore the possibility of applying the anisotropic generalized Hough transform (AGHT) enhanced with a Gabor based time-frequency filtering (GTF) for the determination of the mandibular canal in digital dental panoramic radiographs. The proposed method is based on template matching us- ing the fact that the shape of the mandibular canal is usually the same, followed by a filtering of the accumulator space in the Gabor domain for a precise detection of the position. The proposed procedure consists of a detailed description of the shape of the canal in its canonical form and on preserving Gabor filtering information for sorting the hierarchy of location candidates after applying anisotropically the ex- traction algorithm. The experimental results show that the proposed procedure is robust to recognition under occlusion and under the presence of additional structures e.g. teeth, projection errors.

In this paper, we explore the possibility of applying the anisotropic generalized Hough transform (AGHT) enhanced with a Gabor based time-frequency filtering (GTF) for the determination of the mandibular canal in digital dental panoramic radiographs. The proposed method is based on template matching us- ing the fact that the shape of the mandibular canal is usually the same, followed by a filtering of the accumulator space in the Gabor domain for a precise detection of the position. The proposed procedure consists of a detailed description of the shape of the canal in its canonical form and on preserving Gabor filtering information for sorting the hierarchy of location candidates after applying anisotropically the ex- traction algorithm. The experimental results show that the proposed procedure is robust to recognition under occlusion and under the presence of additional structures e.g. teeth, projection errors.

In this paper, we explore the possibility of applying the anisotropic generalized Hough transform (AGHT) enhanced with a Gabor based time-frequency filtering (GTF) for the determination of the mandibular canal in digital dental panoramic radiographs. The proposed method is based on template matching us- ing the fact that the shape of the mandibular canal is usually the same, followed by a filtering of the accumulator space in the Gabor domain for a precise detection of the position. The proposed procedure consists of a detailed description of the shape of the canal in its canonical form and on preserving Gabor filtering information for sorting the hierarchy of location candidates after applying anisotropically the ex- traction algorithm. The experimental results show that the proposed procedure is robust to recognition under occlusion and under the presence of additional structures e.g. teeth, projection errors.

In this paper, we explore the possibility of applying the anisotropic generalized Hough transform (AGHT) enhanced with a Gabor based time-frequency filtering (GTF) for the determination of the mandibular canal in digital dental panoramic radiographs. The proposed method is based on template matching us- ing the fact that the shape of the mandibular canal is usually the same, followed by a filtering of the accumulator space in the Gabor domain for a precise detection of the position. The proposed procedure consists of a detailed description of the shape of the canal in its canonical form and on preserving Gabor filtering information for sorting the hierarchy of location candidates after applying anisotropically the ex- traction algorithm. The experimental results show that the proposed procedure is robust to recognition under occlusion and under the presence of additional structures e.g. teeth, projection errors.

In this paper, we explore the possibility of applying the anisotropic generalized Hough transform (AGHT) enhanced with a Gabor based time-frequency filtering (GTF) for the determination of the mandibular canal in digital dental panoramic radiographs. The proposed method is based on template matching us- ing the fact that the shape of the mandibular canal is usually the same, followed by a filtering of the accumulator space in the Gabor domain for a precise detection of the position. The proposed procedure consists of a detailed description of the shape of the canal in its canonical form and on preserving Gabor filtering information for sorting the hierarchy of location candidates after applying anisotropically the ex- traction algorithm. The experimental results show that the proposed procedure is robust to recognition under occlusion and under the presence of additional structures e.g. teeth, projection errors.

Bilateral sagittal split osteotomy (BSSO) is the most common procedure used to treat mandibular deformities. BSSO procedures include the Epker technique and the Dal Pont technique which are the most frequently used. Because of the intramandibular pathway of the inferior alveolar nerve (IAN), neurosensory disturbance of the lower lip and chin is the most common complication of BSSO. This study performed quantitative measurements from computed tomographic (CT) data obtained on dry human mandibles. The main aim of the study was to evaluate if mandibular divergence can predict the position of the IAN and the mylohyoid nerve (MHN) to prevent nerve injury., Journal Article, SCOPUS: ar.j, info:eu-repo/semantics/published

Bilateral sagittal split osteotomy (BSSO) is the most common procedure used to treat mandibular deformities. BSSO procedures include the Epker technique and the Dal Pont technique which are the most frequently used. Because of the intramandibular pathway of the inferior alveolar nerve (IAN), neurosensory disturbance of the lower lip and chin is the most common complication of BSSO. This study performed quantitative measurements from computed tomographic (CT) data obtained on dry human mandibles. The main aim of the study was to evaluate if mandibular divergence can predict the position of the IAN and the mylohyoid nerve (MHN) to prevent nerve injury., Journal Article, SCOPUS: ar.j, info:eu-repo/semantics/published

The relative changes in the location of the mandibular canal, mylohyoid line and base of mandible which are caused by loss of teeth were analyzed. One hundred and six mandibles (104 right sides and 106 left sides) from cadavers dissected at Matsumoto Dental University were examined. A soft X-ray of the lateral view of each mandible was taken and converted into an image by scanner. Then the area between the mental foramen and the lingula were divided into 10 partitions on the images. The distances between the mylohyoid line and the alveolar margin (ML-AM), the mandibular canal and the mylohyoid line (MC-ML), and the base of mandible and the mandibular canal (BM-MC), respectively, were measured at the partition lines on the images of the mandibles by a NIH Image software program. The following findings were obtained: After loss of teeth ML-AM and MC-ML change to a statistically significant difference as tested by Mann-Whitney's U-test. ML-AM is affected more strongly than MC-ML by the loss of teeth. However, BM-MC does not change under any condition of tooth loss. It was concluded that after loss of teeth the first to disappear is the alveolar portion, but the atrophy eventually involves part of the mylohyoid line of the mandible., 松本歯科大学の学生実習遺体106体(男性67体、女性39体)より摘出した下顎骨を用い、下顎管および顎舌骨筋線について、下顎体部での位置関係が歯の喪失に伴いどのように影響されるかを調査した。一定基準に基づいて軟Ⅹ線写真撮影を行い、その得られた画像をスキャナーよりパーソナルコンピューターに入力し計測した｡計測のために基準線を設定した｡この基準は、オトガイ孔後縁より下顎小舌後縁間を10等分し、各々に線番号を0-10と設定した｡この基準線が、歯のどの位置を通過するかにより、基準線の下顎体での位置を求めた｡線番号0、2、4、6と対応するのは、第二小臼歯部、第一大臼歯部、第二大臼歯部、第三大臼歯部であった。そこで、この基準線に基づき顎舌骨筋線および下顎管の位置の変化を調査した｡従来より言われているように、顎舌骨筋線から歯槽緑までの距離は、歯の喪失により著明な影響を受けていた｡下顎管と顎舌骨筋線間の距離もまた歯の喪失により影響を受けるが、特に第一･第二大臼歯相当部で著明であった｡しかし、下顎管より下顎骨下縁の距離は、歯の有無にかかわらず変化がなかった｡

There is a high incidence of late sensory paralysis of the lower lip after sagittal split osteotomy and it has been recognized as a serious complication. The purpose of this study was to identify factors that influence the occurrence of late sensory paralysis. The relationships between selected factors (age, location of the mandibular canal on frontal cephalograms, operating time, method of splitting, amount of setback, method of fixation and experience of the surgeon) and sensory paralysis one year postoperatively was investigated on 150 sides (75 patients) after bilateral sagittal split osteotomy. The statistical evaluation was performed by univariate and multivariate analysis. The results were as follows; The incidence of late sensory paralysis was 22.6%. There was a statistical difference in the incidence of paralysis based on the location of the mandibular canal (P<0.001). The other factors were not significant. On multivariate analysis using a logistic regression model, only the location of the mandibular canal was correlated with sensory paralysis (95% confidence interval 0.80-0.93, P=0.0001)., 下顎枝矢状分割術術後の大きな合併症としての長期下唇知覚麻痺に彫響を与えている因子を明らかにするため、術後1年での知覚麻痺と知覚麻痺残存に影響を与えていると考えられる7因子(年齢、下顎管の位置、手術時間、分割方法、骨片の移動量、固定方法、術者の経験年数) との関連について統計学的に検討したので報告する｡対象は、当科で1985年より10年間に両側下顎枝矢状分割術による下顎骨後方移動を行った症例のうち資料の整備した75名150例(両側下顎枝を各1例とする) とした｡結果; 1.単変量解析:正面頭部Ⅹ線規格写真で計測した下顎管の位置に関する因子と知覚麻痺残存とに極めて有意な関連が認められ、下顎管が下顎枝外側に接近することで知覚麻痺残存率が有意に上昇することが示された。一方、年齢、手術時間、分割方法、骨片の移動量、固定方法、術者の経験年数と知覚麻痺残存との間に有意な関連は認めなかった｡ 2.多変量解析:目的変数を知覚麻痺の有無、説明変数を7因子としロジスチック回帰分析を行った結果、下顎管の位置に関する因子はオッズ比の95%信頼区間は0.80-0.93(P=0.0001)となり、他の因子に比し極めて強い関連が認められた｡

Objective: Anatomizing the mental spine area, nutrient foramen system, and mandibular canal to discover anatomical and radiological features of the mandibular mental region. Materials and Methods:Research involved an anatomical study, namely manufacture of gross specimens stained by in-house methods to detect the vascular-nervous tract. It involved craniometric measurements of 200 corpses aged 50-70 without maxillofacial pathology. Using a Gigli saw helped obtain and examine 200 mandibular fragments. The resulting defect was replaced, using an alginate fragment and mimicking denture teeth. The tract was anatomized under the binocular loupe MBS-2, using microsurgical instruments. Bone specimens with the separated vascular-nervous tract were examined by macro- and micro-preparation methods. Results: Comparison of anatomical and radiological findings revealed correlation between the skull type and the mental foramen shape. Macroanatomical and radiological findings showed 3 types of the mental spine canal. Conclusion: The results of the work conducted provide a fair presentation of the peculiar structure of the mental cavity and the intra- and endoosseous branches of the mental nerve, and the canal of its end correlates with the mental spine canal.