Cephalometric X-rays Research Articles

A New Geometric Intersection Point (Ms) to Determine the Spatial Position of Maxillary Sinus

Abstract Introduction: Cephalometeric landmark detection, is a knowledge intensive activity to identify on standardized lateral x-rays of the skull, to perform measurements needed for medical diagnosis, treatment planning and evaluation. For computation of analysis of steps and for determination of underlying structures, provided landmarks should be correctly localized. Due to the complexity of human anatomy sensed in a cephalometric x-ray, the landmarks are localized and constructed. Maxillary sinus has an important role to play in the formation of facial contours. Objective: Our aim is to check the validity of new geometric intersection point Ms, evaluating cephalometerically the spatial position of maxillary sinus and to find any correlation between the spatial position of maxillary sinus and sagittal dysplasias. Study design: A single-institution prospective analysis. Subjects and methods: A total of 20 lateral cephalograms were used, of both sexes, ranging in age from 18-25 years. These radiographs were from subjects, classified into class I and class II on the bases of ANB and Ao-Bo. Maxillary sinus was carefully analyzed and measured in linear dimensions of length and width and its spatial position was calculated by using a new geometric intersection point Ms, created by the intersection of the linear measurements, in relation to the anterior cranial base. The spatial position of maxillary sinus was calculated from the position of the intersection point Ms. The length and height of maxillary sinus was measured and compared in both the groups. Results: The mean of maxillary sinus length (MSL) and height (MSH) was 43.2 ± SD 3.2mm and 41.2 ± SD 3.8mm, respectively for classI (p value=0.595) and 44.2 ± SD 4.9mm and 43.0 ± SD 3.4mm, respectively for class II (p value=0.283). The intersection point Ms depicting centre of maxillary sinus from x-axis (Ms-Msx) was same for both the groups. Mean for Ms-Msy, was 37.3 ± SD 5.7 for class I and 37.8 ± SD 1.9 for class II (p value=0.796). No statistical significance was found among the results in both the groups. Conclusion: The length and height of maxillary sinus was calculated and the centre of maxillary sinus was calculated by the intersection of the two. This new point can contribute in calculating the spatial position of sinus and be an effective measure to study the convexity and concavity of the midface. In the present study, the length and height of the sinus did not alter with the increased or decreased ANB and Ao-Bo. There was no significant spatial position change of maxillary sinus with variation in ANB and Ao-Bo (sagittal). Regarding vertical parameters, Ms may have significant correlation with the various malocclusions.

하악 전돌증 환자에서 악교정 수술방법에 따른 설골과 혀의 위치 및 기도량 변화의 비교

Purpose: The purpose of this study was to compare the changes in the pharyngeal airway space, tongue and hyoid bone positions according to the orthognathic surgical methods of mandibular prognathism. Methods: The subjects included 30 patients (16 males, 14 females) with the skeletal class III malocclusion. Group 1 (10 patients) underwent bilateral sagittal split ramus osteotomy (BSSRO) only; group 2 (10 patients) underwent BSSRO with genioplasty; and group 3 (10 patients) underwent BSSRO, Le Fort I osteotomy. We measured the lines between the selected upper air way, hyoid bone and tongue landmarks on the lateral cephalometric x-ray films of skeletal class III. The measurements were made preoperation, within 1 week after the operation, 3~6 months after the operation and 1 year after the operation. We compared and analyzed the measurements with matched paired t-test and independent samples t-test. Results: There were no postoperative changes in the nasopharyngeal airway space in group 3. The measurements of group 3 also increased during the follow-up period as compared to the preoperative measurements. In group 1, 2 and 3, the immediate postoperative oropharyngeal and hypopharyngeal airway spaces were decreased. In the following period, the hypopharyngeal airway space returned to the preoperative positions, but the oropharyngeal airway space was not significantly changed. The upper and lower tongue was posteriorly repositioned immediately after the surgery. During the follow-up period, the lower tongue position returned to the preoperative position, and the upper tongue position was not significantly changed. Immediately after the surgery, the B point was moved to the posterior position, and a slight anterior advancement was found in the follow-up period. Conclusion: Patients who received the mandibular setback surgery showed a decrease in the posterior airway space, and those who underwent maxillary advancement showed a significant increase of the nasopharyngeal airway space, which remained stable during the evaluation period. The change of the airway space, position of the hyoid bone and tongue did not differ according to the presence or absence of genioplasty.

Lower incisor dentoalveolar compensation and symphysis dimensions among Class I and III malocclusion patients with different facial vertical skeletal patterns

To compare lower incisor dentoalveolar compensation and mandible symphysis morphology among Class I and Class III malocclusion patients with different facial vertical skeletal patterns. Lower incisor extrusion and inclination, as well as buccal (LA) and lingual (LP) cortex depth, and mandibular symphysis height (LH) were measured in 107 lateral cephalometric x-rays of adult patients without prior orthodontic treatment. In addition, malocclusion type (Class I or III) and facial vertical skeletal pattern were considered. Through a principal component analysis (PCA) related variables were reduced. Simple regression equation and multivariate analyses of variance were also used. Incisor mandibular plane angle (P < .001) and extrusion (P = .03) values showed significant differences between the sagittal malocclusion groups. Variations in the mandibular plane have a negative correlation with LA (Class I P = .03 and Class III P = .01) and a positive correlation with LH (Class I P = .01 and Class III P = .02) in both groups. Within the Class III group, there was a negative correlation between the mandibular plane and LP (P = .02). PCA showed that the tendency toward a long face causes the symphysis to elongate and narrow. In Class III, alveolar narrowing is also found in normal faces. Vertical facial pattern is a significant factor in mandibular symphysis alveolar morphology and lower incisor positioning, both for Class I and Class III patients. Short-faced Class III patients have a widened alveolar bone. However, for long-faced and normal-faced Class III, natural compensation elongates the symphysis and influences lower incisor position.

Association between Oro-Facial Defects and Systemic Alterations in Children Affected by Marfan Syndrome

It is important to establish an early diagnosis of the Marfan Syndrome (MFS) for providing an adequate pharmacological or surgical therapy. Nevertheless, this diagnosis may be complex, given the multi-organic involvement of this disease. In this work, we evaluated the oral phenotype in a group of paediatric patients with a clinical diagnosis of MFS, to quantify the association of the oro-facial defects with other systemic alterations. Paediatric subjects who were aged, with a clinical diagnosis of MFS, were selected from our regional Marfan monitoring unit. All the patients were subjected to Paediatric Dentistry examinations and a radiological screening with Panoramic and Cephalometric X-Rays. The aortic dilation (Aortic Z-score value), the hyperlaxity of the ligaments and scoliosis were evaluated by cardio-surgical and orthopaedics specialists. The correlations between the oral and systemic alterations were analyzed by using the chi square test for the nominal variables. We found a significant correlation of the Aortic Z - score with multiple oral defects which included retrognathia, malar hypoplasia, cross bite, oral respiration and an ogival palate. An association of the oral defects with hyperlaxity of the ligaments and scoliosis was also found. Thus, the data suggested that dentists should be more involved in a multidisciplinary approach, to provide an early MFS diagnosis in paediatric patients.

Simultaneous options for cleft secondary deformities

Introduction:So much has been written by so many about secondary procedures in cleft surgery that testify not only the complexity and variable expression of cleft deformity itself but also the need to find methods of primary surgery that will reduce, if not avoid, adverse effects on all the structures and functions involved and affected. It must be the principal aim of cleft surgeon to restore the deformed and displaced regional anatomy to as close to normality as possible, whether or not true hypoplasia exists. The pathogenesis of secondary deformities is related to specific features as: the presence of scar tissues into the cleft basal bone area, that inhibits alveolar growth; scarring of palatal soft tissue, that inhibits growth and causes palatal orientation of dentoalveolar elements; and the exceeding lip tension, that may inhibits maxillary growth along dentoalveolar structures.Materials and Methods:From 2008 to 2011 at the Department of Cranio-Maxillo-Facial Surgery, Santo Spirito Hospital, Rome 25 patients (21 males and 4 females) who had undergone previous surgery for unilateral cleft lip and palate (UCLP) and bilateral cleft lip and palate (BCLP) were enrolled in our study. Diagnosis of deformity was made by means of a cephalometric and photographic analysis (Arnett), gipsometry and a radiological assessment (orthopantomography, lateral and frontal cephalometric X-rays). Moreover, every patient was studied with a temporomandibular joint (TMJ) tomography, TMJ magnetic resonance imaging (MRI) and a computerized gnatography to better evaluate potential TMJ dysfunctions. The surgical procedures adopted simultaneously were: Total or segmental maxillomandibular osteotomies, genioplasty, rhinoplasty, labioplasty, and application of facial prosthesis. Every patient received a postoperative questionnaire to evaluate his/her satisfaction with the surgery performed.Results:The surgical procedures adopted were Le Fort I osteotomy and bilateral sagittal split osteotomy (BSSO) in 16 patients (65%) and only Le Fort I osteotomy in 9 patients (35%). A relapse of malformation occurred in 4.5% of cases. Concerning the patient questionnaire, 96% of patients were satisfied with the jaw surgery and favorable for combined surgery, 88% were satisfied with lip-nose surgery, and finally 76% would advise to a friend.Conclusions:Simultaneous correction of the deformities is indicated as to avoid several surgical distresses for the patient, to improve facial aesthetic and function in one surgical step, and to reduce risk of psychological consequences.

Changes of the upper lip in orthodontic and orthopedic treatment of angle′s class II malocclusion

This study aimed to evaluate the changes in upper lips due to incisors retraction in Class II Division 1 patients treated with mandibular protraction, fixed appliances, and without extraction. The sample consisted of 64 pre- and post-treatment lateral cephalometric X-rays of 32 patients with 9-12 years old (16 men and 16 women), who presented ANB > 4 o , overjet ≥ 4 mm, treated with Balter's Bionator and fixed appliances. The average period between initial and final radiographies was 5 years (maximum of 5.5 years and minimum of 4.5 years). A Student's t-test (P < 0.01) evaluated the statistical significance of differences between the mean values obtained for pre- and post-treatment in each variable, for males and females. Linear regression analysis for hard-tissue variables in relation to soft-tissue variables were also made for correlation. The male group presented cervical point with r = 0.40 and incisal point with r = 0.42. Female subjects showed incisor cervical point with r = 0.86 and incisal point r = 0.74. The average Ls retraction was 0.55 mm in 2.43 mm of incisal point movement and 0.34 mm of cervical point. The nasolabial angle showed increase average of 2° for men and 3.9° for women. There is a difference between genders regarding the lip-incisor relation at this age. Males presented thickening of soft tissue and week correlation between the movement of the incisor and soft tissue both cervical and incisal point. In females' subjects, a strong correlation between the retraction movement and soft tissue, both cervical and incisal point.

Teenage sleep-disordered breathing: Recurrence of syndrome

The study aims to better understand the reappearance of sleep apnoea in adolescents considered cured of obstructive sleep apnoea (OSA) following adenotonsillectomy and orthodontic treatment. The study employs a retrospective analysis of 29 adolescents (nine girls and 20 boys) with OSA previously treated with adenotonsillectomy and orthodontia at a mean age of 7.5years. During follow-up at 11 and 14years of age, patients were clinically evaluated, filled the Pediatric Sleep Questionnaire (PSQ) and had systematic cephalometric X-rays performed by orthodontists. Polysomnographic (PSG) data were compared at the time of OSA diagnosis, following surgical and orthodontic treatment and during pubertal follow-up evaluation. Following the diagnosis of OSA and treatment with adenotonsillectomy and rapid maxillary expansion (Apnea-Hypopnea Index (AHI) 0.4±0.4), children were re-evaluated at a mean age of 11years. During follow-up at 14years, all children had normal body mass indices (BMIs). Teenagers were subdivided into two groups based on complaints: Nine asymptomatic subjects (seven girls and two boys) and 20 subjects with decline in school performance, presence of fatigue, indicators of sleep-phase delays and, less frequently, specific symptoms of daytime sleepiness and snoring. Presence of mouth breathing, abnormal AHI and RDI and significant reduction of posterior airway space (PAS) was demonstrated during repeat polysomnography and cephalometry. Compared to cephalometry obtained at a mean of 11years of age, there was a significant reduction of PAS of 2.3±0.4mm at a mean age of 14years. Previously suggested recurrence of OSA during teenage years has again been demonstrated in this small group of subjects. Prospective investigations are needed to establish frequency of risk, especially in non-orthodontically treated children.

구강 내 장치와 III급 고무줄을 이용한 유치열기 전치부 반대 교합 치료

III급 부정 교합과 전치부 반대 교합은 동양인에게서 더 빈번히 관찰되며 이 문제는 치과 의사뿐 아니라 부모도 쉽게 인지할 수 있다. 유치열기 반대 교합의 경우, 피개량이 깊어질수록 하악의 기능성 전방 변위가 현저해지는데 이를 방치하면 골격성 반대 교합으로 이행될 우려가 있다. 따라서 치료가 필요한 유치열기 반대 교합의 경우 조기에 정확히 진단하는 것이 중요하고 조기교정 치료를 통해 개입할 필요가 있다. 본 증례에서는 유치열기에 전치부 반대 교합을 주소로 내원하여 기능성 반대 교합으로 진단된 만 4세 어린이들에게 구강내 장치를 이용한 치료를 시행하여 정상적 상하악 치열 관계로 개선시켰다. 또한 본과에서 유치열기 반대 교합 치료를 받은 7명의 어린이들의 치료 기간과 사용된 장치를 고찰하고, 측방 두부 규격 방사선 사진 분석을 통해 치료 전후의 상하악의 위치적 관계의 변화, 악골 크기의 변화량 등을 분석하였다. 그 결과 구내 장치와 III급 고무줄을 이용한 치료에서 대부분의 어린이들은 1년 이내에 반대 교합의 개선을 보였고, 그 치료 결과는 전하안면 고경의 수직적 성장을 통한 하악의 후하방 회전에 의한 것으로 나타났다. Class III malocclusion or anterior crossbite is commonly seen in Asian. This problem is easily recognized by dentists and parents. During the primary dentition period, anterior crossbite with functional shift and deep overbite could develop to skeletal protrusive mandible. So, early and proper diagnosis of anterior crossbite which needs prompt treatment is important. These cases showed the early management of crossbite with functional shift in primary dentition using intraoral removable appliance resulting in improvement of intermaxillary relationship. And I analyzed the positional change and the dimensional change during treatment with lateral cephalometric x-ray analysis. Our patients showed vertical dimensional change of lower anterior facial height and clockwise rotation which results crossbite correction in 1 year of treatment period.

Dento-skeletal changes associated with treatment of deep overbite in class II malocclusion

The present study aimed to evaluate the treatment changes in class II patients with deep overbite. A total of 22 females (15-18 years) were treated with fixed orthodontic appliances divided into 2 groups; the first group comprised of 12 cases with class II division 1and the second group ten cases with class II division 2. All cases possessed over bite more than 4 mm, class II more than 4 degrees and had pre and post treatment lateral cephalometric x-ray films. Eleven angular and ten linear cephalometric measurements were recorded and analyzed before and after treatment. The differences in mean values of variables within each studied group were statistically analyzed using Wilcox on singed rank test. On the other hand the mean differences of overbite before and after intervention were compared between the two studied groups using Mann-Whitney test.Results: Bite depth improved an average of 5.6 mm in class II division1, and 2.6 mm in class II division2 with significant differences within and between the studied groups. All measurements showed changes that were statistically significant except SNB0 in both groups, ANB0, OP/MP0, U1-PP, ANS-Me in group 1, and L1-MP in group 2. Conclusion: Bite depth improved due to the changes in the axial inclination of incisor teeth that were decreased in class II division1, while increased in class II division 2, intrusion of lower incisor in class II division1, and intrusion of maxillary incisor in class II division 2 in addition to extrusion of upper and lower molars in both groups.

Hyoid advancement to the mandible (hyo-mandibular advancement)

Hyoid advancement to the mandible was first described in 1984, but was later abandoned by most surgeons for the easier to perform advancement to the laryngeal cartilage. New modifications of the hyo-mandibular advancement technique has made this approach easier to perform and are described in this paper. The hyo-mandibular advancement technique has a higher success rate for the treatment of sleep apnea, especially in women.

Techniques radiographiques utiles en orthodontie

Specialists in dento-facial orthopedics have a large range of dental radiological techniques at their disposal to help them in their diagnostic and therapeutic procedures. Peri-apical, occlusal, panoramic, and cephalometric X-Rays are two-dimensional techniques that orthodontists can complement, if necessary, with Multi slices CT scan or Cone Beam Computed Tomography. Orthodontists must apply and respect quality criteria for each type of film in order to derive the best information from every image and to avoid producing artifacts or false images that will reduce their diagnostic value and, accordingly, the service that they render to patients. Practitioners must be willing to spend the few moments it takes to position patients correctly in the radiological apparatus instead of taking multiple views to compensate for failing to scrupulously follow protocols of radiology.

The efficiency and stability of maxillary expansion with Quadhelix; a longitudinal study

Transverse maxillary deficiencies constitute a routine clinical problem in orthodontics, Quadhelixis one of the slow maxillary expanders which used to solve these problems. The purpose of this study was to investigate the long-term clinical responses of Quadhelixas slow maxillary expander; a treatment performed for early permanent dentition in Class I malocclusion. Subjects and methods: A study sample of 30 patients (13 males and 17 females) were selected on the criteria of having Class I permanent dentition with transverse maxillary deficiency, and mild or no crowding mandibular dental arch, treated with Quadhelix expander without extraction, with active mechanotherapy for teeth alignment (as needed). The mean age of the sample was 12 years and 2 months for girls and 12 years and 11 months for boys at treatment initiation. Cast and cephalometric measurements outcomes were evaluated at pretreatment phase A 0, post- activeexpansion phase A 1, post-retentive phaseA2 (one year after A 1), and at the end of long term follow-up A3(three years after A1). The results were compared to a control group of 30 subjects (15 males and 15 females) of Class I with normal occlusions of the same age group. Simple training to withdraw bad oral habitswas carried out all over the study. Results: Casts and cephalometric x-rays measurements were quantified and compared among phase A0, A1, A2, and A3. Using Student's t-test, the study group demonstrated a significant increase in the arch width values during the activeexpanding phase (P, .001) and less significant increaseduring the long-term follow-up (P, .01). Stable arch length and no increase in the lower facial height were beneficial results. Conclusions: The long-term clinical response demonstrated the efficiency and stability of this type of treatment in achieving maxillary arch width with no threatening of mandibular downward rotation. The follow-up evaluation confirmed the validity of overtreatment.

National reference doses for dental cephalometric radiography

Diagnostic reference levels (DRLs) are an important tool in the optimisation of clinical radiography. Although national DRLs are provided for many diagnostic procedures including dental intra-oral radiography, there are currently no national DRLs set for cephalometric radiography. In the absence of formal national DRLs, the Health Protection Agency (HPA) has previously published National Reference Doses (NRDs) covering a wide range of diagnostic X-ray examinations. The aim of this study was to determine provisional NRDs for cephalometric radiography. Measurements made by the Dental X-ray Protection Service (DXPS) of the HPA, as part of the cephalometric X-ray equipment testing service provided to dentists and dental trade companies throughout the UK, were used to derive provisional NRDs. Dose-area product measurements were made on 42 X-ray sets. Third quartile dose-area product values for adult and child lateral cephalometric radiography were found to be 41 mGy cm² and 25 mGy cm², respectively, with individual measurements ranging from 3 mGy cm² to 108 mGy cm². This report proposes provisional NRDs of 40 mGy cm² and 25 mGy cm² for adult and child lateral cephalometric radiographs, respectively; these doses could be considered by employers when establishing their local DRLs.

Early postnatal development of the mandibular permanent first molar in infants with isolated cleft palate

Based on measurements on dental casts, smaller permanent teeth in children with cleft palate have previously been reported in the literature; however, the early maturation of teeth and the size of the follicles and crowns have not been investigated. The maturation of the mandibular permanent first molar (M1(inf)) is delayed, and the mesiodistal diameters of the follicle and crown of M1(inf), respectively, are reduced in children with isolated cleft palate (ICP). Retrospective, longitudinal. Cephalometric X-rays were available for 2 and 22 months old children with clefts (64 children with ICP, and a control group of 38 children with unilateral incomplete cleft lip). The width of the follicle and the crown of M1(inf), and the maturation of M1(inf) were assessed. Intra-observer error was acceptable. M1(inf) maturation was delayed in children with ICP at both 2 and 22 months of age. The mesiodistal diameter of the crown of M1(inf) in the ICP group was reduced. Thus, the two hypotheses could not be refuted. Children with ICP showed smaller dimensions of the M1(inf) , and in addition, the maturation of M1(inf) was delayed.

Variation with age of dental cephalometric variables in Class II, division 2 patients

The treatment of Angle Class II/2 malocclusion requires an understanding not only of the dental and maxillofacial features but also of the changes occurring with age in the dental relationships. This paper attempts to determine certain dental relationships in patients with Angle II/2 malocclusion and any changes that might occur with age. The study material included 96 lateral cephalometric X-rays of patients with Angle II/2 malocclusion, the youngest of whom was 7 years old and the eldest 35. Six cephalometric measurements were performed on every cephalometric X-ray. Statistical processing of data included one-variable analyses and correlations of two variables. Statistical one-variable analysis used methods from descriptive statistics. Methods of inferential statistics have been applied in order to revel statistical significance. The evaluation of the findings of this research study concluded that, in patients with Angle II/2 malocclusion, maxillary central incisors presented pronounced palatal tipping, which exacerbated significantly with age, while mandibular incisors displayed reduced labial tipping and projection, which significantly reduced with age. Furthermore, it was found that there was pronounced incisor overjet, which increased with age, due to increased protrusion of mandibular incisors.

Cephalometry and prediction of oral appliance treatment outcome

Predicting which patients with obstructive sleep apnea (OSA) will be successfully treated with mandibular advancement splints (MAS) remains elusive. Developing simple daytime measurements and tests to predict treatment outcome would enhance MAS treatment. The purpose of this study was to assess the clinical utility of anthropomorphic measurements and cephalometric X-rays in the prediction of MAS treatment outcome in OSA. Anthropomorphic measurements and cephalometric X-rays from 72 OSA patients who had presented to a tertiary referral sleep clinic were analyzed retrospectively. Treatment response was defined as ≥50% reduction in Apnea/Hypopnea Index (AHI; criterion 1); ≥50% reduction and residual AHI less than 20/h (criterion 2); ≥50% reduction in AHI and residual AHI less than 10/h (criterion 3); and ≥50% reduction in AHI and residual AHI less than 5/h (criterion 4). This was done to reflect the differences in the clinical definition of treatment success in the literature. A good response occurred in 56% (40 patients) according to criterion 1; 54% (39 patients) according to criterion 2; 46% (33 patients) according to criterion 3; or 39% (28 patients) according to criterion 4. Age and gender were found to be significant predictors for criteria 1 and 2. Age and soft palate length were found to be significant predictors for criteria 3 and 4. Equations to predict MAS treatment response were derived as equations were to predict final AHI. Certain cephalometric and anthropomorphic measurements impact on MAS treatment outcome. This study adds to the current literature and implies that MAS success is (to some degree) related to anatomical characteristics.

Real-Time Radiophotography

Patients are always concerned about facial profile changes after orthognathic surgery. Orthodontists and oral and maxillofacial surgeons could use cephalometric software to create a post-treatment image, which is a combination of a radiograph and a photograph. Cephalometric software with imagemorphing programs can integrate the cephalometric analysis, patient photographs, and treatment plan. This has made it easy for the patient to understand the outcome of the treatment. However, slight imperfections can arise when superimposing the 2 images (photograph and cephalogram), because the source of the photographs and cephalograms differs in time and space. The noncongruence of both types of images has been frequently observed in the case of soft tissue profiles, especially in the lip region. If both images could be simultaneously filmed, the imperfections could be reduced to a minimum. Therefore, we developed a new technology to obtain identical images using real-time radiophotography. Technical Design Although many cephalometric imaging software programs can rapidly retrace and recombine radiographs and photographs to predict the treatment outcome, variations still occur because of the different intervals used for both types of images. The variations in the different portions of the radiograph and the corresponding photograph have always been ignored. However, our method can control the variations to a minimum using real-time radiophotography. First, it is essential to locate the focal spot of the x-ray tube. An x-ray tube is enclosed in a leaded shield with an opening that is usually covered by glass or aluminum, allowing useful beams of x-rays to emerge from the head of the x-ray machine. Using the instruction manual of the x-ray machine, we can calculate the relative area of the focal spot to be positioned almost in the center of the x-ray head. The position of the focal spot is very important in determining the location of the digital camera, which is essential for obtaining consistently accurate photographs. For an esthetic design, most cephalometric x-ray machines do not possess a glass window in front of the x-ray tube. Several cephalometric projections are required to detect the position of the digital camera as accurately as possible without impeding the path of the x-ray beam. The digital camera can be set almost parallel to the path of the central x-ray beam (Figs 1, 2). The remote control can be used to manipulate the camera’s function outside the radiographic room. Therefore, the camera and x-ray machine can easily be operated simultaneously. If the digital camera does not have a remote control, a 10-second delay self-timer can be set to operate the shutter in synchronicity with the x-ray machine. Thus, a greater congruence between both images can be obtained. It is also essential to determine the magnification differences between the radiographs and photographs of the different portions of the face. Owing to divergence from the focal spot, the x-ray projections will be fan-shaped and will have different magnifications on the film. However, it can be easy to adjust the magnification using software such as Microsoft PowerPoint, Apple Keynote, PhotoImpact, and so forth (Fig 3).

Mass retraction movement of the anterior upper teeth using orthodontic mini-implants as anchorage

Several studies have demonstrated the application of mini-implants in the orthodontic treatment as anchorage during the retraction movement of the anterior teeth. This study was designed to evaluate the mass retraction movement of the anterior upper teeth using orthodontic mini-implants as anchorage. Nine patients with class I malocclusion and Angle's class II, needing extractions of the upper first premolars, were enrolled in this case series. The retraction was performed using sliding mechanics and orthodontic anchorage on mini-implants. Measures were taken by initial and final cephalometric X-rays of the retraction movement to evaluate whether the mini-implants remained stationary and displacements of the incisors and the upper first premolars. Out of 18 mini-implants, 8 mesialized (0.45mm, average) and 3 extruded (0.14mm, average). The upper incisors were retracted on the average of 4.21mm, extruded 0.33mm, and tipped 10.3°. There were no statistical significant modifications in the placement of the posterior teeth. Although there was a very small displacement of the mini-implants, they still provided an adequate anchorage for the retraction of the anterior teeth, and there was no loss in the anchorage of the posterior teeth.

Orthodontic cephalometric X-rays overdone: a commentary

Free AccessLetter to the editorOrthodontic cephalometric X-rays overdone: a commentaryJay W FriedmanJay W FriedmanSearch for more papers by this authorPublished Online:28 Jan 2014https://doi.org/10.1259/dmfr/87387415SectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail AboutThis letter is in response to the recent DFMR article: Mutagenicity and cytotoxicity assessment in patients undergoing orthodontic radiographs.1In the introduction, the authors state that “a lateral cephalometric X-ray must be obtained for all patients, before the start of treatment, when the information obtained from this film is expected to benefit or enhance the formulation of the patient's diagnosis and treatment plan.”The reference in support of this statement is to a paper on legal and ethical aspects for post-treatment records.2 Obviously, this concerns the protection of orthodontists from malpractice suits and has no bearing on whether or not cephalographs benefit or enhance diagnosis and treatment. It might better be termed “defensive orthodontic radiography.”The introductory statement may be appropriately termed a “pious platitude” about which it is assumed no one will disagree because obviously no one would recommend X-rays that would not benefit or enhance diagnosis and treatment. The only problem is that it is a false platitude.An evidence-based study by Atchison et al3 demonstrated that cephalographs are of no value in deciding on treatment in approximately 70% of orthodontic cases. Nonetheless, cephalographs continue to be routinely prescribed for routine orthodontic cases for which there is no documented evidence.Although conceding that cephalographs should be employed only when beneficial, the authors state that “At present, lateral and frontal cephalograms are considered mandatory in orthodontic therapy.” With emphasis on “and frontal” patients are being subjected to these X-rays whether or not they are beneficial, “Although it is generally accepted that there is no safe level of radiation exposure…”.But is this a peripheral criticism of the paper, which is not about the necessity or validity of cephalographs for orthodontic diagnosis and treatment, but rather is the radiation harmful to the tissues radiated? The answer is yes and no. There was a large increase (69%) in cytotoxic cellular damage 10 days after radiation, but whether this translates to significant damage in terms of overall health is not known. There was no difference in the number of cells exhibiting DNA (micronucleus) damage before and after. In other words, this type of radiography does not appear to increase the risk of cancer in the oral tissues.Whether the damage that occurs was due more to cephalographic or panoramic radiation was not considered in this study and is probably not an issue with respect to the oral tissues. What the study does not consider is the effect of cephalographic radiation on the brain. If oral cells are damaged, then is it not likely that brain cells are damaged? We can conclude that cephalography is not only cytotoxic to oral tissues but also cytotoxic to brain tissues.The authors conclude “radiography is able to induce cytotoxicity… radiographs should be used only when necessary.” yet they accede to mandatory cephalometric X-rays for all orthodontic patients as if their need is self-evident and without any potential harm.In the absence of palpable benefit, it is unconscionable that children continue to be exposed to brain radiation and its cytotoxic effect on brain cells by orthodontists who may be more concerned with protecting themselves from negligence lawsuits while performing negligent diagnosis.References1 Angeleri F , Carlin V , Saez DM , Pozzi R , Ribeiro DA . Mutagenicity and cytotoxicity assessment in patients undergoing orthodontic radiographs. Dentomaxillofac Radiol 2010;39:437–440. Link ISI, Google Scholar2 Jerrold L . Litigation, legislation, and ethics. Post treatment records. Am J Orthod Dentofacial Orthop 2008;133:124–126. Crossref Medline ISI, Google Scholar3 Atchison KA , Luke LS , White SC . Contribution of pretreatment radiographs. to orthodontists' decision making. Oral Surg Oral Med Oral Pathol 1991;71:238–245. Crossref Medline ISI, Google Scholar Previous article Next article FiguresReferencesRelatedDetails Volume 39, Issue 8December 2010Pages: 455-524 2010 The British Institute of Radiology History Published onlineJanuary 28,2014 Metrics Download PDF

Análise da expansão rápida da maxila por meio da tomografia computadorizada Cone-Beam

Diante do diagnóstico de uma arcada maxilar esqueleticamente atrésica, o tratamento de escolha geralmente é a expansão ortopédica da maxila, envolvendo a separação da sutura palatina mediana. A avaliação dessa sutura era basicamente realizada por meio da radiografia oclusal superior, limitando sua análise em norma frontal. Da mesma forma, quantificar essa atresia radiograficamente nas telerradiografias cefalométricas sempre foi um obstáculo para o clínico, devido à grande sobreposição das estruturas faciais. O advento da tomografia computadorizada na Odontologia tem transformado a forma de diagnóstico devido à alta precisão na avaliação das dimensões das estruturas faciais, possibilitando quantificar de maneira fiel o comportamento das hemimaxilas, a inclinação dentária, a formação óssea na sutura nos três planos do espaço, assim como a reabsorção óssea alveolar e demais consequências da expansão palatina