Diagnostic aids in orthodontics

for Students of Orthodontics

1. Presented by- Dr. Smaraki Mahapatra PG 1 ST Year (Orthodontics) Under the guidance of – Dr. Neetu Dabla (Professor and Guide) DIAGNOSTIC AIDS

2. CONTENTS 1.Introduction 2.Classification of diagnostic aids 3. Essential diagnostic aids a. Case history b. Clinical examination c. Study models d. Radiographs and facial photographs 4.Supplemental diagnostic aids 5. Recent advances 6. Conclusion 7. References

3. Introduction Comprehensive orthodontic diagnosis is established by use of certain orthodontic clinical implements called diagnostic aids in orthodontics. Diagnostic aids help in proper diagnosis and treatment planning of orthodontist during examining patients.

4. Classification of diagnostic aids Essential diagnostic aids Supplemental diagnostic aids

5. Essential diagnostic aids Case history Clinical examination Study models Certain radiographs 1.Periapical radiographs 2.Bite wing 3.Panoramic Facial photographs

6. Supplemental diagnostic aids 1.Specialized Radiographs Cephalometric Occlusal Lateral jaw views Cone shift technique 2.Electromyographic examination of muscle activity 3.Hand-wrist radiograph to asess bone age or maturation age 4.Endocrine tests 5.Estimation of BMR 6.Diagnostic set up 7. Occlusogram

7. ESSENTIAL DIAGNOSTIC AIDS

8. CASE HISTORY 1 1.Personal details 2.Chief complaint 3. Medical history 4.Dental history 5.Prenatal history 6.Post-natal history 7. Family history

9. Personal details Name - Age - Sex - Case no - Occupation - Address - Date -

10. Chief Complaint The patient’s chief complaints should in his/her own words. 2.This helps the clinician in identifying the priorities and desires of the patient. 3. It can be elicited by way of an interview or by asking the patient to fill the questionnaire.

11. Medical history A thorough medical history should be taken . Conditions which might affect orthodontic treatment include the following. Rheumatic Fever- Invasive procedures such as band placement and removal should be covered with antibiotic regime.A chlorhexidine rinse prior to the adjustment of a fixed appliance is a useful adjunct.

12. Epilepsy- Removable orthodontic appliances are contraindicated in patients who exhibit poorly controlled epilepsy due to risk of airway obstruction during seizures. Diabetes Mellitus- Orthodontic treatment should be avoided in patients with poorly controlled DM. Periodontal evaluation is mandatory before starting orthodontic procedure. Patients should be have their normal meal and medications before appointments.

13. Haemophilia Care should be taken to avoid irritation in the gingiva , lip or cheeks from the orthodontic appliances. 2. Care should be taken during insertion and removal of the arch wire in order to avoid any injury to the oral soft tissues. 3.Elasteromeric ligatures are preferred over wire ligatures to secure the arch wire as it reduces the risk of irritation of the soft tissues.

14. Dental history Components of past dental history includes Previous restorative Endodontic or Oral surgical treatments Reasons for tooth loss of teeth Experience with orthodontic appliance and dental prosthesis By noting this , the dentist will get an accurate idea of the importance he gives to good dental treatment and how conscious he has been in persuing a goal of good oral health.

15. Pre-natal history The pre-natal history should include information on the condition of the mother during pregnancy and the type of delivery. The use of certain drugs like thalidomide or affection with some infections during pregnancy like German measles can result in congenital deformities of the child. Information should be gathered on the type of delivery. Forcep delivery predispose to TMJ Iinjuries that can manifest as marked mandibular growth retardation.

16. Post-natal History The post-natal history includes information on the type of feeding, presence of habits and on the milestones of normal development. Tongue thrusting Thumb sucking

17. Family history This is very important for many hereditary diseases. Many diseases recur in families like hemophilia, diabetes mellitus, hypertension and heart diseases.

18. CLINICAL EXAMINATION

19. General examination Height and weight Gait Posture Body build

20. Extraoral Examination Shape of head Facial form Facial asymmetry Facial Profile Facial divergence Ant-post jaw relationship Vertical skeletal relationship Facial proportion Examination of lips, nose, chin prominences

21. Intraoral examination Examination of the following 1.Tongue 2. Palate 3.Gingiva 4.Frenal attachments 5.Tonsils and adenoids 6. Assessment of dentition

22. F unctional examination Improper functioning of the stomatognathic system can result in various malocclusions. The functional examination should include : Assessment of postural rest position and inter occlusal space Path of closure Assessment of respiration Examination of TMJ Examination of swallowing Examination of speech 22

23. STUDY MODEL 1.Orthodontic study models are accurate Plaster reproductions of the teeth and their surrounding soft tissues. Uses - They enable the study of the occlusion from all aspects They enable accurate measurements to be made in a dental arch. They help in measurement of arch length, arch width and tooth size. They help in treatment progress by the dentist as well as the patient. They help in assessing the nature and severity of malocclusion.

24. RADIOGRAPHS They are two types:- 1.Intraoral 2.Extraoral Intraoral is again divided in to 3 types:- 1.Periapical 2. Bitewing 3. Occlusal Extraoral radiographs:- 1.Panoromic 2. Cephalometric a. Lateral ceph b. Postero -anterior cehalogram Others- Hand-wrist radiograph.

25. INTRAORAL RADIOGRAPH Periapical radiograph Bite-wing Radiograph

26. EXTRAORAL RADIOGRAPH OPG

27. PA VIEW OF SKULL

28. FACIAL PHOTOGRAPHS Uses of facial photographs :- 1.They are useful in assessment of facial symmetry, facial type and profile. 2.They serve as diagnostic records. 3.They help in assessing the progress of the treatment.

29. EXTRA-ORAL PHOTOGRAPHS

30. INTRA-ORAL PHOTOGRAPHS

31. SUPPLEMENTAL DIAGNOSTIC AIDS

32. SPECIALIZED RADIOGRAPHS

33. a.Cephalometric Radiographs Uses of cephalometric radiographs in orthodontics:- 1.It helps in planning treatment for an individual. 2.Cephalometrics helps in predicting the growth related changes and changes associated with surgical treatment. 3.Cephalometrics is a valuable aid in research work involving the cranio-dento facial region.

34. b. Occlusal intraoral films The following are uses of occlusal radiographs:- 1.To locate impacted or unerupted teeth. 2. To locate supernumerary teeth. 3.To locate foreign bodies in the jaws and stones in salivary ducts. 4.To diagnose the presence and extent of fractures. 5. They are useful in orthodontics to study the effects of arch expansion procedures.

35. c. Selected lateral jaw views 1.Lateral oblique view is one of the most enterprising and satisfactory techniques of having an extraoral view of the jaw. Indications:- a. Unerupted teeth b. Fracture c. Pathology d. Mandibular 3 rd molar e. Periapical area

36. d. Cone shift technique

37. Also called 1.Tube shift technique 2.Clark’s technique 3. Buccal object rule 4.SLOB technique The principle states that the object closest to the buccal surface appears to move in the direction opposite the movement of the cone or tube head, when compared with the second film. Object closest to the lingual site appears to move(on a film) in the same direction that the cone moved.

38. 2. ELECTROMYOGRAPHIC EXAMINATION It is a procedure used for recording the electrical activity of the muscles. Electromyogram is a record obtained by such a procedure. Uses :- In severe Class II division I malocclusion the upper lip is hypofunctional . Thus during swallowing , the lower lip extends upwards and forwards to force the maxilla labially and a strong mentalis activity is seen. EMG can be used to study such condition. After orthodontic therapy EMG is done to achieve if muscle balance is achieved.

39. 3.HAND WRIST RADIOGRAPH Useful in estimating the skeletal age of a person. The hand and wrist region have a number of small bones whose appearance and progress of ossification occurs in a predictable sequence. This enables a skeletal age of a patient. They are useful in assessing growth for planning growth modification procedures and surgical resective procedures.

40. 4.ENDOCRINE TESTS A number of endocrinal disorders , infectious conditions and metabolic disturbances can predispose to malocclusion .

41. 5.ESTIMATION OF BMR BMR helps in assessment of thyroid function. It helps in the calculation of a daily energy requirement of a person. It helps in planning diet for an individual. For adult men BMR is 34-37 kcal/ squremeter /hour. For adult women BMR is 24kcal/ squaremeter /hour.

42. 6.DIAGNOSTIC SETUP It was first proposed by H.D Kesling . The diagnostic set up is made from extra set of trimmed and polished study models. Uses :- 1. It is useful in visualizing and testing the effect of complex tooth movements and extractions on the occlusion. 2. The patient can be motivated by simulating the various corrective procedures on the cast. 3. Tooth size- arch length discrepancies can be visualized by means of occlusal set up.

43. 7.OCCLUSOGRAM It is a tracing of a photograph or photocopy of a dental arch. It is used for following purposes:- 1.To estimate occlusal relationships 2. To estimate arch length and width 3. To estimate spacing and crowding 4. To estimate anchorage requirements 5. To estimate the tooth movements in all 3 planes of space

44. RECENT ADVANCES IN DIAGNOSTIC AIDS

45. XERORADIOGRAPHY It is completely dry, non-chemical process that makes use of the electrostatic process that makes use of the electrostatic process as in the xerox machines. It was invented by Chester F. Carlson in 1937. It makes the use of an aluminium plate that is coated with a layer of vitreous selenium. The selenium particles are given a uniform elecrostatic charge.

46. The charged plate is placed in a light-tight, air-tight cassette. When the film is exposed it causes selective discharge of the selenium depending upon the amount of radiation used and the relative density of the object. This pattern of electric discharge on the plate is called latent image . Once the latent image is converted to a real image on to a paper , the selenium plate can be discharged, cleaned and used again. It can be reused as many as 1000 times.

47. Advantages ;- 1. Cephalometric landmarks are easily identified. 2. Ease of viewing .No special light source is required. 3. Reduction in exposure time. 4. Ease in manipulation. 5. No need of dark rooms for developing.

48. DIGI GRAPH The Digi Graph is a synthesis of video imaging, computer technology and sonistic digitising . The digigraph enables the clinician to perform non-invasive and non-radiographic cephalometric analysis.

49. DIGIGRAPH consists of sonic cephalometric device

50. Two video cameras, permanently aimed and focused, are mounted on the vertical column. Lighting emanates from sources inside the boom, thus insuring that all images are properly illuminated.

51. According to the manufacturer's information, one can perform cephalometric analysis and monitor patient treatment progress as often a necessary without radiation exposure.

52. The Digi Graph allows all patient’s models, radiographs, photographs, cephalograms and tracings to be stored on one small disc, thereby reducing storage requirements. It is a valuable tool for improving communication among clinician, patient and staff.

53. The cephalometric landmarks are digitised by lightly touching the sonic digitising probe to a point on the patient’s skin corresponding to it. This emits a sound, which then recorded by the microphone and monitored as X, Y and Z co-ordinates.

54. Features of Digi graph A landmark can be identified as a point in three dimensions. A cephalometric analysis can be made independently of head position. Parallelism of X-ray in mid- sagittal plane and symmetry of anatomic morphology between left and right sides is not necessary.

55. The Digi Graph workstation’s hardware and software enable the performance of cephalometric analyses, tracing , superimposition and VTO . The programme is capable of 14 analyses. Measurements for any selected analysis can be displayed on the monitor and the observed values are shown along with the patient norm adjusted for age, sex, race and head size including standard deviations.

56. Optional components include : 1. A consultation unit : It transports information in to the operatory, doctor’s office/consultation area , thus allowing viewing and comparison of information and development of VTO . 2. A high resolution video camera with a telephoto lens for taking intraoral views by framing the video image.

57. 3. A light box for X-rays and a study model holder for video imaging that will be included in the floppy disk. 4. Camera and video printer for producing copies of video monitor information .

58. MRI It makes the use of two fundamental properties of protons, i.e spin and small magnetic movements. Advantages :- 1. MRI does not have hazards as it uses non- ionising electromagnetic radiation. 2. Greater tissue characterisation is possible. 3. Anatomical details are good as in C.T. scan.

59. Disadvantages of MRI Time taken is more. Not used in patients with cardiac pacemaker. Non- visualization of bone makes it useless in bony lesions.

60. TOMOGRAPHY Tomography can be conventional or computed tomography. Conventional - It is a process by which a layer of an image with in the body is produced while the images of structures above and below that layer are made invisible by blurring. Computed – It is also called C.T. Or CAT –These are mainly complex imaging systems which use thin beams of X-ray that move in a synchronous manner with an array of detectors which calculate and attenuate the X ray beams at different angles and in different planes.

61. DIGITAL SUBSTRACTION RADIOGRAPHY This is an image enhancement method that removes the structured noise from the images. The result is the area of change clearly displayed either against a neutral grey background . The digital substraction technique selectively enhances the differences between two imges . It is impossible to achieve perfect registration of images during registration .

62. LASER HOLOGRAPHY Holography is a photographic technique for recording and reconstructing images in such a way that the 3D aspect of an object can be obtained. The recorded image is called a hologram . Laser is light amplification by stimulated emission of radiation. Application - 1. Storage of study model images 2. To study the effect of maxillary expansion of facial skeletons.

63. CINERADIOGRAPHY This is basically a radiographic motion picture. The subject is oriented properly and stabilized in a modified cephalostat . This diagnostic aid is used to visualize the swallowing pattern of the patient. The X- ray motion picture is studied using a movie projector .

64. TECHNETIUM SCAN It is usually recommended in cases of abnormally growing facial bones, the commonest condition being unilateral condylar hyperplasia . It is indicated in condylar hyperplasias to confirm the activity of the condylar active growth site. Technetium scan also be useful in skeletal class III cases to confirm the cessation of the active growth before undertaking orthognathic surgery.

65. Unilateral condylar hyperplasia

66. CBCT The first Cone-Beam Computed Tomography ( CBCT ) scanner was used in the Mayo Clinic, USA for performing angiography in 1982. Advantages :- 1. Lower radiation exposure. 2. Reduced scan time 3. Lower cost than CT scan Disadvantages ;- 1. Limited information on soft tissue structures 2. Lower contrast resolution –less discrimination between different tissue types.

67. PRINCIPLE OF CBCT

68. Applications of CBCT in orthodontics Assessment of an impacted teeth e.g. canines(including evaluation of resorption of an adjacent tooth) For assessment and planning of orthognathic surgery Assessment of cleft palate.

69. Contraindication of CBCT Caries detection Routine method of assessing periodontal bone support Periapical pathosis Demonstration of root canal anatomy

70. STEREOPHOTOGRAMMETRY (3D FACIAL PHOTOGRAPHS) Soft tissue facial analysis Evaluation of the craniofacial growth and development Measurement of esthetic facial parameters Photos -light ; Gramma -to draw; Metron -to measure It involves photographing a 3D object from two different co-planar views in order to derive a 3D reconstruction of the images. Stereophotogrammetry refers to the special case where two cameras, configured as a stereo pair , are used to recover 3D distances of features on the surface of the face by means of triangulation . Uses;-

71. SURE SMILE TECHNOLOGY It can substantially reduce many common errors in fixed appliance treatment, and it can enhance the quality of care afforded to the patient by compressing the treatment cycle and reducing the number of appointments. Sure smile gives the clinician powerful tools to deliver consistent, high quality care to all patients, regardless of practice volume. In short,this technology is designed for the patient-centered practice.

72. PHOTOCEPHALOMETRY Thomas in 1978 developed photocephalometry to better visualize the soft tissues of patient. Three radio-opaque metallic markers with holes are placed on patient’s skin with adhesives and standard lateral and anteroposterior cehalograms are taken. Using the same position lateral and frontal photographs are taken. The photographs are printed to the same size as the radiographs and are superimposed over the radiographic tracing taking the metallic markers as the guide.

73. CONCLUSION A thorough knowledge of the clinician about the disease and along with diagnostic aids will help the orthodontic diagnosis and treatment successful . No doubt in it.

74. REFERENCES Contemporary Orthodontics . William R. Proffit . Sixth edition. Diagnosis and management of malocclusion and Dentofacial Deformities. OP kharbanda.2 nd edition. Orthodontic Principles and Practice.Phulari.2 nd edition. Text Book Of Orthodontics. Gurkeet Singh.3 rd edition. Color Atlas of Orthodontic diagnosis.Thomas Rakosi .

75. Holograms in orthodontics:A universal sysyem for the production , development, and illumination of holograms for the storage and analysis of dental casts.Romeo . AJODO.Oct 1995;Vol 108 (4):443-7. Radiographic exposure conditions and resultant skin doses in application of xeroradiography to the orthodontic diagnosis. Nakasima et al. AJODO . Dec 1980;646-56. Digital revolution in orthodontic diagnosis.Annals of Geriatric Education and Medical sciences. July-Dec 2017;Vol 4(2):38-40.