Q U I N T E S S E N C E I N T E R N AT I O N A L
RADIOLOGY
A classification of alveolar bone tissue
Ana Carla Raphaelli Nahás-Scocate
Ana Carla Raphaelli Nahás-Scocate, DMD, MSc, PhD1/Marcos Coral Scocate, DMD, MSc2 The objective was to present a way of using cone-beam computed tomographic (CBCT) images to classify alveolar bone tissue. CBCT images were acquired from PreXion3D tomography. Sagittal images of right and left maxillary and mandibular central incisors were obtained. A new grading scale was created based on the presence or absence of bone in each third of the tooth in buccal and lingual surfaces. The tooth was classified into nine alveolar bone conditions: B1L1, B1L2, B1L3, B2L1,
B2L2, B2L3, B3L1, B3L2, B3L3. This classification is an additional tool to provide orthodontic and periodontic professionals the precise information needed in order to prevent periodontal problems or to avoid exacerbating them, both situations that might arise during orthodontic therapy. Furthermore, the grading will assist and enhance effective communication between professionals in dentistry. (Quintessence Int 2014;45:515–519; doi: 10.3290/j.qi.a31542)
Key words: bone tissue, classification, orthodontics, periodontics, tomography
When planning orthodontic cases, different alternative treatments relating to dental alignment are taken into account, such as tooth extractions, interproximal dental stripping, and buccolingual tooth movement to expand the arch. However, if the professional does not consider the biologic limits of the patient’s alveolar bone anatomy, excessive buccolingual tooth movement might contribute to a future periodontal problem such as bone dehiscence with unfavorable mucogingival aspect.1,2 The bone dehiscence is characterized by the lack of alveolar bone resulting in root exposure.2 This anatomic situation is evident by the presence of gingival recession, which is the apical movement of the marginal gingiva in relation to cementoenamel junction (CEJ). The gingival recession causes an unattractive smile as well as 1
Associate Professor, Department of Orthodontics, School of Dentistry, University of São Paulo City, São Paulo, Brazil.
2
Private Practice, São Paulo, Brazil; and Postgraduate in Orthodontics, University of Camilo Castelo Branco, Campinas, Brazil.
Correspondence: Dr Ana Carla Raphaelli Nahás-Scocate, Department of Orthodontics, School of Dentistry, University of São Paulo City, Rua Cesario Galeno 448/475, Bairro Tatuapé, CEP 03071-000 São Paulo, Brazil. Email: [email protected]
VOLUME 45 • NUMBER 6 • JUNE 2014
dentin sensitivity and susceptibility to root decay. The development of gingival recession is multifactorial, and although bone dehiscence is one of the predisposing factors, the biotype of the gingiva is more important. Nowadays, there is a high demand from adult patients with periodontal problems seeking orthodontic treatment, especially since esthetics and self-esteem play an important role in social, family, and professional environments. As there is continuous integration between periodontics and orthodontics, a new treatment concept demonstrates the importance of periodontal therapy and the benefits that orthodontic treatment offers patients who suffer from periodontal disease. Periodontal diagnosis relies primarily on traditional two-dimensional representation of the alveolar bone. Though conventional and digital radiography are very useful and have less radiation exposure, they still cannot determine a three-dimensional (3D) architecture of osseous defects. As a result of scientific development in imaging that provides 3D images with detailed bone structures, diagnostic tools in dentistry have therefore become more precise and reliable.3,4 Cone-beam com-
515
Q U I N T E S S E N C E I N T E R N AT I O N A L Nahás-Scocate/Scocate
puted tomography (CBCT) offers a realistic representation of the patient’s anatomy, hence it is an ideal tool to evaluate the characteristics and alveolar bone alterations associated with the orthodontic treatment. Since this technological development, orthodontic professionals now include this 3D imaging during their clinical routine when it is necessary to complement the diagnosis.5,6 The question remains of how to classify the alveolar bone tissue through the use of CBCT images. We therefore propose classifying the different periodontal conditions, hence creating a new standardized grading scale, in order to internationally enhance and benefit communication between professionals.
REPORT The classification of different conditions of alveolar bone insertion is demonstrated through the use of CBCT images taken from patients with favorable and unfavorable periodontal bone tissue conditions in the region of maxillary and mandibular central incisors. CBCT images published in this article were obtained from PreXion3D tomography. The tomography settings were as follows: high resolution (0.1 mm voxel), 0.02 mm of focal vision, 5 × 5 field of view, acquisition time high definition (HD) of 33 seconds, and reconstruction time of 30 seconds. The CBCT scans were saved as digital imaging and communications in medicine (DICOM) files. Volumetric reconstructions of the maxilla and mandible were carried out using the software NemoScanNxPro (Software Nemotec). We obtained sagittal images of right and left maxillary and mandibular central incisors (teeth 11, 21, 31, and 41 according to FDI notation), and used the central axis slice of each tooth. After saving the central image of the tooth, the CEJ and the root apex were identified. The distance between them was considered as the total length of the root. This length was divided equally and horizontally into three parts in order to take into account both buccal and lingual surfaces. Each third was then named and designated a number as follows: 1. cervical 2. middle 3. apical.
516
According to the tooth surface, buccal (B) and lingual (L), we then assigned the following (Fig 1): • B1: buccal cervical surface • B2: buccal middle surface • B3: buccal apical surface • L1: lingual cervical surface • L2: lingual middle surface • L3: lingual apical surface. The different conditions of alveolar bone insertion were visually classified according to the presence or absence of bone in each third of the tooth, in buccal and lingual surfaces. This classification is preceded by the number that corresponds to the tooth.
Classification • • • • • • • • •
B1L1: bone tissue present in cervical buccal and lingual surfaces (Fig 2) B1L2: bone tissue present in cervical buccal and middle lingual surfaces B1L3: bone tissue present in cervical buccal and apical lingual surfaces B2L1: bone tissue present in middle buccal and cervical lingual surfaces B2L2: bone tissue present in middle buccal and lingual surfaces (Fig 3) B2L3: bone tissue present in middle buccal and apical lingual surfaces B3L1: bone tissue present in apical buccal and cervical lingual surfaces B3L2: bone tissue present in apical buccal and middle lingual surfaces B3L3: bone tissue present in apical buccal and lingual surfaces.
Figure 4 exemplifies the nine possible conditions of alveolar bone insertion, with their respective abbreviations and classifications. After classifying the tooth in question, the amount of bone tissue can be measured in each third by using a software ruler, which is positioned perpendicular to the axis of the tooth, from the external surface of the root to the most external alveolar bone surface. In this
VOLUME 45 • NUMBER 6 • JUNE 2014
Q U I N T E S S E N C E I N T E R N AT I O N A L Nahás-Scocate/Scocate
11B1L1
B3 B2
L3
B1
B1
L2
L2
L1
L1
B2
31B2L2
Fig 1 Cervical (1), middle (2), and apical (3) thirds to the buccal (B) and lingual (L) surfaces.
Fig 2 Tooth 11 B1L1: bone tissue present to the cervical buccal and lingual surfaces of the right maxillary central incisor.
Fig 3 Tooth 31 B2L2: bone tissue present to the middle buccal and lingual surfaces of the left mandibular central incisor.
ECJ 1/3 1/3 apex
B1 L1
B1 L2
B1 L3 ECJ 1/3 1/3 apex
B2 L1
B2 L2
B2 L3 ECJ 1/3 1/3 apex
B3 L1 Fig 4
B3 L2
B3 L3
Classification: different conditions of alveolar bone insertion.
way, the analysis abbreviations can be complemented by numeric values, such as the example B1 = 0.72 mm; B 2 = 1.02 mm; B 3 = 1.47 mm; L 1 = 2.39 mm; L2 = 5.56 mm; and L3 = 8.06 mm (Fig 5). The bone thickness measurements can be directly obtained from the radiograph when the image is reformatted to the actual size of the tooth and developed to a scale of 1:1.
VOLUME 45 • NUMBER 6 • JUNE 2014
Fig 5 Bone thickness measurements in each third, to the buccal and lingual surfaces, of the right maxillary central incisor by using a software ruler.
DISCUSSION There has been an increase in the number of adult orthodontic patients in recent years, representing 20% in this area.7 If an adult patient presents periodontal problems that had not previously been detected, the use of an orthodontic appliance might aggravate their situation.
517
Q U I N T E S S E N C E I N T E R N AT I O N A L Nahás-Scocate/Scocate
Faced with this scenario, orthodontists must be aware of the importance of the diagnosis and the treatment plan offered to these adult patients. This knowledge of normal and abnormal periodontal characteristics is of extreme importance when determining the risk of a patient developing future periodontal problems when tooth movement is induced.6 The need for multidisciplinary treatment,1 such as the diagnostic tools used in periodontics, aid and inform the orthodontist. These tools are used to evaluate the patient’s actual condition with regards to the depth of probing, bleeding areas during probing, tooth mobility, interproximal bone loss, furcation defect, and gingival recession. The assessment and interpretation of these aspects, as well as the decision to scale and polish coronary root surface or to perform periodontal surgery, prior to applying braces, are prerequisite to good planning and professional conduct. The aim of creating a standardized grading of alveolar bone tissue is to provide the clinicians with one more tool to classify the tooth in relation to the presence or absence of bone tissue in buccal and lingual surfaces. Moreover, this standardized classification will offer an improved and more dynamic communication between professionals in dentistry. It is didactic and visually rapid to comprehend, as it classifies the tooth into nine alveolar bone conditions: B1L1, B1L2, B1L3, B2L1, B2L2, B2L3, B3L1, B3L2, B3L3. Moreover, this classification can be used to take into account the bone height at the mesial and distal surfaces, considering M for mesial and D for distal. Thus, if the four surfaces are taken into account, this grading scale can provide 81 different alveolar bone classifications. During the phases of orthodontic treatment, the classification does not vary in relation to the amount of bone tissue, regardless of the size of the root. Hence, even though root resorption is inevitable during orthodontic treatment, this does not affect the classification results. On the other hand, if the tooth experiences significant root resorption, a classification of B2L2, for instance, may become B3L3 without any additional periodontal breakdown. Although the length of the root will differ during treatment phases, the depth of probing will confirm the maintenance of bone level.
518
Associated with this classification, the orthodontist must routinely take into account the patient’s medical and dental background. According to the American Association of Orthodontists and the American Academy of Periodontists,7 there are four items that must be considered in the identification of patients who are at risk of developing periodontal disease: • Does patient have routine checkups? • Is the patient diabetic? • Is the patient a smoker? • Has the patient has already undergone periodontal therapy? Even though the usefulness of CBCT for periodontal applications is in the early stages of being understood, it is found to be as accurate as direct measurements when using a periodontal probe and as reliable as radiographs for analyzing interproximal areas. CBCT therefore provides even better diagnostic and quantitative information about periodontal bone levels in three dimensions.8 However, quality and precision of the images depend on the resolution of the machine, especially the voxel size.3,6 Although there is no consensus on the specification of CBCT equipment for the evaluation of alveolar bone, 0.1 mm voxel size was used in this work as it is known that the smaller the voxel size, the higher the spatial resolution, and the smaller the field of view, the less noise from scatter radiation. Exposing the patient to additional radiation will depend on the necessity of diagnosing and confirming his morphologic characteristics. The decision should stem from a comprehensive assessment of the advantages and disadvantages to each patient. In order to use this classification, the professional can determine a protocol that guarantees the best tomography image, as the grading shown in this work is simply to classify the tooth into different alveolar bone conditions through the use of CBCT images. Even though there have been innumerous publications about assessing alveolar bone through the use of sagittal image slices, which confirms reliability of this 3D diagnostic method,9 the main aim of this article is to offer professionals an innovative classification grade
VOLUME 45 • NUMBER 6 • JUNE 2014
Q U I N T E S S E N C E I N T E R N AT I O N A L Nahás-Scocate/Scocate
that would ease communication and enhance collaboration between the different members of the treatment team. This grading scale has proved to be very useful and this is the first attempt to internationally systematize and classify the amount of alveolar bone insertion through the use of CBCT images.
CONCLUSION This standardized classification of alveolar bone tissue aims to offer another tool to aid the diagnosis of periodontal bone insertion by using CBCT data. Moreover, this grading scale will provide a scientific method that will enhance effective communication between professionals in dentistry.
REFERENCES 1. Nahás-Scocate ACR. The importance of knowledge and the benefits of interdisciplinary treatment. Orthodontics 2011;12:285–286. 2. Evangelista K, Vasconcelos Kde F, Bumann A, Hirsch E, Nitka M, Silva MA. Dehiscence and fenestration in patients with Class I and Class II division 1 malocclusion assessed with cone-beam computed tomography. Am J Orthod Dentofacial Orthop 2010;138:133.e1–7; discussion 134–136. 3. Patcas R, Muller L, Ullrich O, Peltomaki T. Accuracy of cone-beam computed tomography at different resolutions assessed on the bony covering of the mandibular anterior teeth. Am J Orthod Dentofacial Orthop 2012;141:41–50. 4. Gracco A, Luca L, Bongiorno MC, Siciliani G. Computed tomography evaluation of mandibular incisor bony support in untreated patients. Am J Orthod Dentofacial Orthop 2010;138:179–187. 5. Timock AM, Cook V, McDonald T, et al. Accuracy and reliability of buccal bone height and thickness measurements from cone-beam computed tomography imaging. Am J Orthod Dentofacial Orthop 2011;140:734–744. 6. Nahás-Scocate ACR, Brandão AS, Patel MP, Lipiec-Ximenez ME, Chilvarquer I, Valle-Corotti KM. Bone tissue amount related to upper incisors inclination. Angle Orthod 2013 Jul 24 [Epub ahead of print]. 7. American Association of Orthodontists / AAO Introduces Periodontic Screening Protocols. Available at: https://www.aaomembers.org/Resources/Publications/ebulletin-07-27-12.cfm#perio. Accessed 27 July 2012. 8. Mohan R, Singh A, Gundappa M. Three-dimensional imaging in periodontal diagnosis: utilization of cone beam computed tomography. J Indian Soc Periodontol 2011;15:11–17. 9. Fleiner J, Hannig C, Schulze D, Stricker A, Jacobs R. Digital method for quantification of circumferential periodontal bone level using cone beam CT. Clin Oral Investig 2013;17:389–396.
RADIOLOGY
A classification of alveolar bone tissue
Ana Carla Raphaelli Nahás-Scocate
Ana Carla Raphaelli Nahás-Scocate, DMD, MSc, PhD1/Marcos Coral Scocate, DMD, MSc2 The objective was to present a way of using cone-beam computed tomographic (CBCT) images to classify alveolar bone tissue. CBCT images were acquired from PreXion3D tomography. Sagittal images of right and left maxillary and mandibular central incisors were obtained. A new grading scale was created based on the presence or absence of bone in each third of the tooth in buccal and lingual surfaces. The tooth was classified into nine alveolar bone conditions: B1L1, B1L2, B1L3, B2L1,
B2L2, B2L3, B3L1, B3L2, B3L3. This classification is an additional tool to provide orthodontic and periodontic professionals the precise information needed in order to prevent periodontal problems or to avoid exacerbating them, both situations that might arise during orthodontic therapy. Furthermore, the grading will assist and enhance effective communication between professionals in dentistry. (Quintessence Int 2014;45:515–519; doi: 10.3290/j.qi.a31542)
Key words: bone tissue, classification, orthodontics, periodontics, tomography
When planning orthodontic cases, different alternative treatments relating to dental alignment are taken into account, such as tooth extractions, interproximal dental stripping, and buccolingual tooth movement to expand the arch. However, if the professional does not consider the biologic limits of the patient’s alveolar bone anatomy, excessive buccolingual tooth movement might contribute to a future periodontal problem such as bone dehiscence with unfavorable mucogingival aspect.1,2 The bone dehiscence is characterized by the lack of alveolar bone resulting in root exposure.2 This anatomic situation is evident by the presence of gingival recession, which is the apical movement of the marginal gingiva in relation to cementoenamel junction (CEJ). The gingival recession causes an unattractive smile as well as 1
Associate Professor, Department of Orthodontics, School of Dentistry, University of São Paulo City, São Paulo, Brazil.
2
Private Practice, São Paulo, Brazil; and Postgraduate in Orthodontics, University of Camilo Castelo Branco, Campinas, Brazil.
Correspondence: Dr Ana Carla Raphaelli Nahás-Scocate, Department of Orthodontics, School of Dentistry, University of São Paulo City, Rua Cesario Galeno 448/475, Bairro Tatuapé, CEP 03071-000 São Paulo, Brazil. Email: [email protected]
VOLUME 45 • NUMBER 6 • JUNE 2014
dentin sensitivity and susceptibility to root decay. The development of gingival recession is multifactorial, and although bone dehiscence is one of the predisposing factors, the biotype of the gingiva is more important. Nowadays, there is a high demand from adult patients with periodontal problems seeking orthodontic treatment, especially since esthetics and self-esteem play an important role in social, family, and professional environments. As there is continuous integration between periodontics and orthodontics, a new treatment concept demonstrates the importance of periodontal therapy and the benefits that orthodontic treatment offers patients who suffer from periodontal disease. Periodontal diagnosis relies primarily on traditional two-dimensional representation of the alveolar bone. Though conventional and digital radiography are very useful and have less radiation exposure, they still cannot determine a three-dimensional (3D) architecture of osseous defects. As a result of scientific development in imaging that provides 3D images with detailed bone structures, diagnostic tools in dentistry have therefore become more precise and reliable.3,4 Cone-beam com-
515
Q U I N T E S S E N C E I N T E R N AT I O N A L Nahás-Scocate/Scocate
puted tomography (CBCT) offers a realistic representation of the patient’s anatomy, hence it is an ideal tool to evaluate the characteristics and alveolar bone alterations associated with the orthodontic treatment. Since this technological development, orthodontic professionals now include this 3D imaging during their clinical routine when it is necessary to complement the diagnosis.5,6 The question remains of how to classify the alveolar bone tissue through the use of CBCT images. We therefore propose classifying the different periodontal conditions, hence creating a new standardized grading scale, in order to internationally enhance and benefit communication between professionals.
REPORT The classification of different conditions of alveolar bone insertion is demonstrated through the use of CBCT images taken from patients with favorable and unfavorable periodontal bone tissue conditions in the region of maxillary and mandibular central incisors. CBCT images published in this article were obtained from PreXion3D tomography. The tomography settings were as follows: high resolution (0.1 mm voxel), 0.02 mm of focal vision, 5 × 5 field of view, acquisition time high definition (HD) of 33 seconds, and reconstruction time of 30 seconds. The CBCT scans were saved as digital imaging and communications in medicine (DICOM) files. Volumetric reconstructions of the maxilla and mandible were carried out using the software NemoScanNxPro (Software Nemotec). We obtained sagittal images of right and left maxillary and mandibular central incisors (teeth 11, 21, 31, and 41 according to FDI notation), and used the central axis slice of each tooth. After saving the central image of the tooth, the CEJ and the root apex were identified. The distance between them was considered as the total length of the root. This length was divided equally and horizontally into three parts in order to take into account both buccal and lingual surfaces. Each third was then named and designated a number as follows: 1. cervical 2. middle 3. apical.
516
According to the tooth surface, buccal (B) and lingual (L), we then assigned the following (Fig 1): • B1: buccal cervical surface • B2: buccal middle surface • B3: buccal apical surface • L1: lingual cervical surface • L2: lingual middle surface • L3: lingual apical surface. The different conditions of alveolar bone insertion were visually classified according to the presence or absence of bone in each third of the tooth, in buccal and lingual surfaces. This classification is preceded by the number that corresponds to the tooth.
Classification • • • • • • • • •
B1L1: bone tissue present in cervical buccal and lingual surfaces (Fig 2) B1L2: bone tissue present in cervical buccal and middle lingual surfaces B1L3: bone tissue present in cervical buccal and apical lingual surfaces B2L1: bone tissue present in middle buccal and cervical lingual surfaces B2L2: bone tissue present in middle buccal and lingual surfaces (Fig 3) B2L3: bone tissue present in middle buccal and apical lingual surfaces B3L1: bone tissue present in apical buccal and cervical lingual surfaces B3L2: bone tissue present in apical buccal and middle lingual surfaces B3L3: bone tissue present in apical buccal and lingual surfaces.
Figure 4 exemplifies the nine possible conditions of alveolar bone insertion, with their respective abbreviations and classifications. After classifying the tooth in question, the amount of bone tissue can be measured in each third by using a software ruler, which is positioned perpendicular to the axis of the tooth, from the external surface of the root to the most external alveolar bone surface. In this
VOLUME 45 • NUMBER 6 • JUNE 2014
Q U I N T E S S E N C E I N T E R N AT I O N A L Nahás-Scocate/Scocate
11B1L1
B3 B2
L3
B1
B1
L2
L2
L1
L1
B2
31B2L2
Fig 1 Cervical (1), middle (2), and apical (3) thirds to the buccal (B) and lingual (L) surfaces.
Fig 2 Tooth 11 B1L1: bone tissue present to the cervical buccal and lingual surfaces of the right maxillary central incisor.
Fig 3 Tooth 31 B2L2: bone tissue present to the middle buccal and lingual surfaces of the left mandibular central incisor.
ECJ 1/3 1/3 apex
B1 L1
B1 L2
B1 L3 ECJ 1/3 1/3 apex
B2 L1
B2 L2
B2 L3 ECJ 1/3 1/3 apex
B3 L1 Fig 4
B3 L2
B3 L3
Classification: different conditions of alveolar bone insertion.
way, the analysis abbreviations can be complemented by numeric values, such as the example B1 = 0.72 mm; B 2 = 1.02 mm; B 3 = 1.47 mm; L 1 = 2.39 mm; L2 = 5.56 mm; and L3 = 8.06 mm (Fig 5). The bone thickness measurements can be directly obtained from the radiograph when the image is reformatted to the actual size of the tooth and developed to a scale of 1:1.
VOLUME 45 • NUMBER 6 • JUNE 2014
Fig 5 Bone thickness measurements in each third, to the buccal and lingual surfaces, of the right maxillary central incisor by using a software ruler.
DISCUSSION There has been an increase in the number of adult orthodontic patients in recent years, representing 20% in this area.7 If an adult patient presents periodontal problems that had not previously been detected, the use of an orthodontic appliance might aggravate their situation.
517
Q U I N T E S S E N C E I N T E R N AT I O N A L Nahás-Scocate/Scocate
Faced with this scenario, orthodontists must be aware of the importance of the diagnosis and the treatment plan offered to these adult patients. This knowledge of normal and abnormal periodontal characteristics is of extreme importance when determining the risk of a patient developing future periodontal problems when tooth movement is induced.6 The need for multidisciplinary treatment,1 such as the diagnostic tools used in periodontics, aid and inform the orthodontist. These tools are used to evaluate the patient’s actual condition with regards to the depth of probing, bleeding areas during probing, tooth mobility, interproximal bone loss, furcation defect, and gingival recession. The assessment and interpretation of these aspects, as well as the decision to scale and polish coronary root surface or to perform periodontal surgery, prior to applying braces, are prerequisite to good planning and professional conduct. The aim of creating a standardized grading of alveolar bone tissue is to provide the clinicians with one more tool to classify the tooth in relation to the presence or absence of bone tissue in buccal and lingual surfaces. Moreover, this standardized classification will offer an improved and more dynamic communication between professionals in dentistry. It is didactic and visually rapid to comprehend, as it classifies the tooth into nine alveolar bone conditions: B1L1, B1L2, B1L3, B2L1, B2L2, B2L3, B3L1, B3L2, B3L3. Moreover, this classification can be used to take into account the bone height at the mesial and distal surfaces, considering M for mesial and D for distal. Thus, if the four surfaces are taken into account, this grading scale can provide 81 different alveolar bone classifications. During the phases of orthodontic treatment, the classification does not vary in relation to the amount of bone tissue, regardless of the size of the root. Hence, even though root resorption is inevitable during orthodontic treatment, this does not affect the classification results. On the other hand, if the tooth experiences significant root resorption, a classification of B2L2, for instance, may become B3L3 without any additional periodontal breakdown. Although the length of the root will differ during treatment phases, the depth of probing will confirm the maintenance of bone level.
518
Associated with this classification, the orthodontist must routinely take into account the patient’s medical and dental background. According to the American Association of Orthodontists and the American Academy of Periodontists,7 there are four items that must be considered in the identification of patients who are at risk of developing periodontal disease: • Does patient have routine checkups? • Is the patient diabetic? • Is the patient a smoker? • Has the patient has already undergone periodontal therapy? Even though the usefulness of CBCT for periodontal applications is in the early stages of being understood, it is found to be as accurate as direct measurements when using a periodontal probe and as reliable as radiographs for analyzing interproximal areas. CBCT therefore provides even better diagnostic and quantitative information about periodontal bone levels in three dimensions.8 However, quality and precision of the images depend on the resolution of the machine, especially the voxel size.3,6 Although there is no consensus on the specification of CBCT equipment for the evaluation of alveolar bone, 0.1 mm voxel size was used in this work as it is known that the smaller the voxel size, the higher the spatial resolution, and the smaller the field of view, the less noise from scatter radiation. Exposing the patient to additional radiation will depend on the necessity of diagnosing and confirming his morphologic characteristics. The decision should stem from a comprehensive assessment of the advantages and disadvantages to each patient. In order to use this classification, the professional can determine a protocol that guarantees the best tomography image, as the grading shown in this work is simply to classify the tooth into different alveolar bone conditions through the use of CBCT images. Even though there have been innumerous publications about assessing alveolar bone through the use of sagittal image slices, which confirms reliability of this 3D diagnostic method,9 the main aim of this article is to offer professionals an innovative classification grade
VOLUME 45 • NUMBER 6 • JUNE 2014
Q U I N T E S S E N C E I N T E R N AT I O N A L Nahás-Scocate/Scocate
that would ease communication and enhance collaboration between the different members of the treatment team. This grading scale has proved to be very useful and this is the first attempt to internationally systematize and classify the amount of alveolar bone insertion through the use of CBCT images.
CONCLUSION This standardized classification of alveolar bone tissue aims to offer another tool to aid the diagnosis of periodontal bone insertion by using CBCT data. Moreover, this grading scale will provide a scientific method that will enhance effective communication between professionals in dentistry.
REFERENCES 1. Nahás-Scocate ACR. The importance of knowledge and the benefits of interdisciplinary treatment. Orthodontics 2011;12:285–286. 2. Evangelista K, Vasconcelos Kde F, Bumann A, Hirsch E, Nitka M, Silva MA. Dehiscence and fenestration in patients with Class I and Class II division 1 malocclusion assessed with cone-beam computed tomography. Am J Orthod Dentofacial Orthop 2010;138:133.e1–7; discussion 134–136. 3. Patcas R, Muller L, Ullrich O, Peltomaki T. Accuracy of cone-beam computed tomography at different resolutions assessed on the bony covering of the mandibular anterior teeth. Am J Orthod Dentofacial Orthop 2012;141:41–50. 4. Gracco A, Luca L, Bongiorno MC, Siciliani G. Computed tomography evaluation of mandibular incisor bony support in untreated patients. Am J Orthod Dentofacial Orthop 2010;138:179–187. 5. Timock AM, Cook V, McDonald T, et al. Accuracy and reliability of buccal bone height and thickness measurements from cone-beam computed tomography imaging. Am J Orthod Dentofacial Orthop 2011;140:734–744. 6. Nahás-Scocate ACR, Brandão AS, Patel MP, Lipiec-Ximenez ME, Chilvarquer I, Valle-Corotti KM. Bone tissue amount related to upper incisors inclination. Angle Orthod 2013 Jul 24 [Epub ahead of print]. 7. American Association of Orthodontists / AAO Introduces Periodontic Screening Protocols. Available at: https://www.aaomembers.org/Resources/Publications/ebulletin-07-27-12.cfm#perio. Accessed 27 July 2012. 8. Mohan R, Singh A, Gundappa M. Three-dimensional imaging in periodontal diagnosis: utilization of cone beam computed tomography. J Indian Soc Periodontol 2011;15:11–17. 9. Fleiner J, Hannig C, Schulze D, Stricker A, Jacobs R. Digital method for quantification of circumferential periodontal bone level using cone beam CT. Clin Oral Investig 2013;17:389–396.
