Cephalometric Films Research Articles

A Longitudinal Cephalometric Study of Dento-facial Growth from 5 to 15 Years

Analysis of serial lateral cephalometric films for 85 subjects at 5, 10 and 15 years revealed that the behaviour of nine mean angular dimensions was variable, indicating a change in facial shape. However, the range of individual variation was considerable.

The effect of activator treatment on Class II malocclusions

It was the purpose of this investigation to study the effect of activator treatment of Class II malocclusions in the mixed-dentition period. A group of treated patients was compared with a similar group of untreated Class II malocclusion patients. The criteria for selection and matching of the patients in the two groups included age, sex, dental maloclusion, and observation time. Lateral cephalometric films before treatment, after treatment, and after the retention period were compared and revealed clinically and statistically significant differences between the activator group and the control group. Differences in mean changes are described as follows: 1. 1. The effect of treatment was usually of dentoalveolar origin with a major favorable change in position of the upper incisors. 2. 2. The lower incisors were slightly intruded without significant protrusion. 3. 3. The improvement of the relationship between the upper and lower molars was caused mostly by tooth movement within the dentoalveolar area. 4. 4. The average orthopedic effect of treatment was limited, in spite of individual cases with excellent response. A significant improvement of the anteroposterior relationship between the maxilla and the mandible was registered, as well as an increase in the lower face height and a slightly steeper mandibular plane angle. 5. 5. No differences in the amount of mandibular growth were recorded. 6. 6. Several years after the retention period the dentoalveolar treatment effect upon the maxilla was quite evident, with no sign of relapse.

Mucogingival changes resulting from mandibular incisor tooth movement

This study involved a cephalometric analysis of 1,150 fully treated orthodontic cases evaluated by Kodachrome slides, plaster casts, and cephalometric films to determine changes in the width of keratinized gingiva relative to lower incisor tooth movement and to ascertain the incidence of mucogingival problems in orthodontic patients. It was apparent that in a small percentage of cases visible mucogingival changes occurred and could be statistically correlated with the magnitude and direction of tooth movement. In this group of patients 1.3 percent (sixteen) showed a decrease in the width of keratinized gingiva with either minimal movement or some labial movement of the mandibular incisors; 0.69 percent (eight) had an increase in keratinized gingival width concomitant with significant lingual positioning of the lower incisors. The salient point to be made is that with an initial minimal or inadequate width of keratinized gingiva (0 to 2 mm.), mandibular incisor tooth movement over a period of treatment could significantly affect the final quality of gingival health in the critical mandibular anterior region.

A Method of Superimposing Serial Lateral Cephalometric Films for the Purpose of Comparison: A Preliminary Report

A method is described for superimposing and comparing serial lateral cephalometric films using de Coster's line, the Adams Blink Comparator and correction for vertical movements of Nasion due to growth. Using the method no significant change (P < 0·05) was recorded in Cranial Base Angle for a group of 85 subjects between 5 and 15 years. It is suggested that the method may remove inaccuracies due to vertical movements of Nasion.

An evaluation of extraoral combined high-pull traction and cervical traction to the maxilla

The effects of extraoral combined high-pull traction and cervical traction of known duration (mean, 122 days) and magnitude (2.5 to 3 pounds total per side) were studied by means of serial lateral cephalometric head films of thirty patients. The lateral cephalometric head films used were taken at three different times: before the extraoral force was applied, after the prescribed period of continuous headgear wear, and as long as possible after the extraoral force was discontinued. Changes in the dentition and associated structures were described both for the period of continuous headgear wear and for an average of 3.2 years later. The following conclusions are based on statistical analysis of the observed changes: 1. The position of the maxilla and the palatal plane was not significantly affected by relatively short periods of extraoral combined high-pull traction and cervical traction to the maxillary first molars as used for this investigation. 2. The maxillary first molars can be moved distally and bodily with this appliance without extrusion. 3. On the average, the mandibular first molars uprighted distally in response to the extraoral force to the maxilla. 4. The maxillary and mandibular first molars demonstrated a strong tendency to recover to their original positions and inclinations relative to their respective bases during the posttreatment period. 5. The amount and direction of growth in the posttreatment period may be important in determining how the Class I relationship is maintained.

Effect of palatoplasty and cleft extent on facial and dental relations

Clinical evaluation and lateral cephalometric films were made of 88 Caucasian females, in three age groups and all with isolated clefts of the palate, to evaluate the effect of palatoplasty and the extent of the cleft in the palate on facial and dental relations. From the findings in this investigation it can be concluded that modifications of the Wardill-Kilner palatoplasty necessitated by the extent of the cleft in the palate did not result in any consistently significant changes in the skeletal-facial relationships. Dentally, on the other hand, there was an increased incidence of malocclusion in the group with severe palatal clefts.

Hormonal effects on orthodontic tooth movement in cats—A pilot study

s of papers presented before the Research Section of the American Association of Orthodontists, Ne’w Orleans, La., May 3, 1971 Changes in Tongue Position and Activity Following Mandibular Osteotomy N. A. Wickwire and W. R. Proffit University of Kentucky, College of Dentistry, Lexington, Ky. This study of tongue response and activity was developed from serial cephalometric films and lingual pressure recordings. Preoperative and postoperative cephalograme were analyzed to determine the extent and direction of changes of the odontoid process, the body of the hyoid, and the mandible following surgical treatment. The postoperative response of the mandibular setback in nineteen of twenty-two patients was a posterior deflection of the hyoid body. The hyoid was elevated or depressed in negative correlation with mandibular vertical positioning. In the absence of mandibular vertical change, the vertical changes of the hyoid related to the direction and extent of the hinging of the odontoid process, These movements of the hyoid served to preclude change in the pharyngeal space. This constancy enforces the concept of reflex maintenance of airway patency. Analyses made 1 year postoperatively showed stable mandibular positioning in ten patients. Five patients showed mandibular anterior repositioning, with a mean of -0.6 mm. In three of these patients with mandibular relapse the hyoid was seen to be assuming a more anterior position. Lingual pressure changes, as measured by pressure transducers mounted in a palate-covering device, also indicate that the tongue repositions after the surgical procedure, then returns somewhat toward its original position in the postoperative period. Tongue-tip pressure in most patients decreases after surgery, then returns to approximately the original level. If tongue-tip pressure increases after the operation, the incisor position is likely to be unstable, and a

The borderline patient and tooth removal

1. 1. Nine borderline cases treated with the removal of four first premolars were compared with nine closely matched borderline cases treated with the removal of four second premolars. The differences in incisal and lip changes were analyzed by means of lateral cephalometric films. Tests of significance of difference between the treatment results of the groups were made. 2. 2. The mandibular incisors demonstrated a lesser amount of posterior repositioning in relation to the symphysis when four second premolars were removed (0.01 level). 3. 3. The maxillary incisors were repositioned less posteriorly in relation to deep cranial and facial structures when four second premolars were removed (0.05 level). 4. 4. There was no significant difference in lip retraction between the first-premolar-removal group and the group in which four second-premolars were removed. 5. 5. The mandibular incisors were repositioned less posteriorly in relation to the esthetic plane when four second premolars were removed (0.05 level). 6. 6. An analysis of the treatment response to premolar removal in borderline cases was discussed, and information was presented to assist in obtaining a harmonious incisor-to-lip relationship following treatment.

A blink viewer for comparing serial cephalometric films and dental casts

A blink viewer for comparing serial cephalometric films and dental casts

A cephalometric study of normal and defective -s- articulation and variations in incisor dentition.

The purpose of this study was to define variation in /s/ articulation associated with differences in incisor dentition. Articulatory relationships, defined by cephalometric films, were studied in normal speakers with normal occlusion and complete dentition, normal speakers with normal molar relationships and missing maxillary incisors, and /s/ defective speakers with normal molar relationships and missing maxillary incisors. Adequacy of /s/ articulation for the total sample of 39 children was determined by two separate auditory ratings. Significant differences between normal and defective /s/ articulation were related to the environmental characteristics of the anterior oral constriction. Speakers with defective /s/ articulation excessively fronted the tongue tip. Other differences were related to the antero-postero and vertical placement of the tongue tip, to the extent of mandibular protrusion-retrusion, and to the vertical position of the upper lip. There was no significant difference between children with normal and defective /s/ articulation in regard to the degree of vertical constriction between the midline of the tongue and dental-alveolar complex. These findings appear to be consistent with current physiological phonetic theory.

The construction and application of templates in the surgical reduction of mandibular prognathism

Summary A method of constructing templates from cephalometric films is described. These templates are intended to be placed directly upon that part of the mandible in which the osteotomy is to be performed. Although cephalometric films have been used by Converse (1963) and Joffe (1964) as an indirect aid to treatment planning, and by many such as Goldstein (1947) and Poulton, Taylor and Ware (1963)for the post-operative evaluation, there does not seem any instance of their use for the manufacture of templates to be used at operation.Hillerstrom and Nyquist (1954) were able to indicate the correct direction of a ramus osteotomy by mechanical means on a special articulator, but regarded their apparatus as more of scientific than of clinical interest. Although there have been instances where an operator will not count it of importance to sever the inferior dental bundle as Winter et al. (1949) reported, it would seem much more worth while to take pains to avoid damage to these structures if possible and the use of templates as described is a simple way of doing this.

15. 規格レントゲン写真の適正濃度と顔面幅径について

15. 規格レントゲン写真の適正濃度と顔面幅径について

Cephalometric x-ray evaluation of the vertical osteotomy correction of mandibular prognathism

The use of cephalometric films has been shown to be helpful in the planning and evaluation of surgical corrections of mandibular prognathism. More precise treatment results have been obtained than would have been possible if occlusion had been the only guide in treatment. In each of the thirty cases in which the vertical osteotomy was performed the correction proved to be satisfactory, without such problems as nonunion of fragments or anterior open-bite. Five of the cases were analyzed in detail and showed an original posterior chin movement of between 10 and 16 mm., followed by 2 to 3 mm. of forward chin adjustment. The correction tended to increase the angle of the mandible with the cranium. On the basis of these findings, an overcorrection of about 2 mm. may be advisable in the surgical treatment of mandibular prognathism. No further changes were found following the first year after treatment. The patients have been uniformly pleased with the improved function and facial appearance achieved.

Cephalometrics and longitudinal research

Summary While the sources of error inherent in measurements from cephalometric films are satisfactorily small for many purposes, they should be given special attention when long-term individual rates and patterns of growth or short-term changes that occur during orthodontic treatment are being studied. One source of these errors is blurring. This can be reduced by using an x-ray tube with a small focal spot, a high-kilovolt technique with a grid to absorb some secondary radiation, large tube-to-film distances, and a short exposure time. A description of one installation has been given, with suggestions for further improvement. For stated reasons, the earposts have been eliminated for lateral films. A certain amount of error occurs in the procedures for selecting and measuring from cephalometric films. Attention has been directed toward procedures which reduce these sources of unreliability.

Position of the maxillary first permanent molar in the cephalofacial complex: A study in three dimensions

1. 1. In the present study we have selected the records of 102 children and nine adults from the files of the Philadelphia Center for Research in Child Growth. The children were all of dental stage III C to IV A, with a chronological age range of 11:3 to 13:7. The study is essentially cross sectional. 2. 2. Sample breakdown is as follows: normal occlusion, twenty-four boys and twenty-nine girls; Class II, Division 1 malocclusion, twenty-nine boys and girls, grouped; Class III malocclusion, eleven boys and girls, grouped; nine Negro boys and girls, grouped, with normal occlusion; the nine adults, male and female, grouped, had mixed occlusion. 3. 3. For each case lateral and anteroposterior roentgenographic cephalometric films, taken in the Broadbent-Bolton apparatus, were analyzed, together with dental models. The main comparative analysis, in the present study, is between the groups with normal occlusion and those with Class II, Division 1 malocclusion. 4. 4. In this study we have employed previously defined landmarks and/or end points in the lateral film, but we have presented an entirely new series of such landmarks and/or end points in the P-A film. The aim is to permit a technical and visual correlation between the two views so that any specific structure, such as 6 may be oriented and understood in three planes of space. 5. 5. In the P-A film we have established three main zones (Fig. 4): horizontal (H), unpaired; central (C), vertical in position, unpaired; lateral (L), paired. The major contents of each zone or structure, as seen in the x-ray film, are carefully defined and described. 6. 6. In the lateral film, three zones, in an anteroposterior orientation, are given (Fig. 5): anterior (A), medial (M), and posterior (P). 7. 7. A technique employing millimeter paper is given which permits the orientation of comparable lateral and P-A tracings, in the same child, at the same age. Also, a technique is presented to permit direct comparison of x-ray films (lateral and P-A) with dental models. 8. 8. The position of 6 anteroposteriorly, as seen in the lateral x-ray film, is as follows: 8.1. (a) The distance Te-Na = ANS 6 8.2. (b) Position of 6 to the temporal arc (Te) varies directly as does ANS to the anterior arc. 8.3. (c) This suggests that 6 position in the arch varies as does position of 1 . 8.4. (d) The anteroposterior position of 6 is influenced by size of teeth, position of incisors, muscle balance, and the position of the palate in the cephalofacial complex. 8.5. (e) The anteroposterior position of 6 is not, as Angle claimed, fixed; hence, it cannot be absolutely basic to an occlusal classification which assumes 6 to be stable and fixed. 9. 9. The position of 6 transversely, as seen in the P-A x-ray films, is as follows: 9.1. (a) In normal occlusion its variability is of the order of 1 to 2 mm. 9.2. (b) Class II, Division 1 malocclusions tend to have a smaller bimolar dimension, while in Class III the reverse is true. 9.3. (c) The bicanine diameter approximates three-fifths of the bimolar diameter, regardless of occlusal category; the Class II, Division 1 is in the lower end of the distribution of total range. 9.4. (d) The position of 6 transversely is influenced by both muscular and mandibular function. 10. 10. The position of 6 vertically, as seen in the lateral x-ray film, is as follows: 10.1. (a) The vertical variation of 6 is small, of the order of ±1 mm. 10.2. (b) Hence, the position of 6 is relatively very stable in this plane. 11. 11. This study, cross sectional in nature and based upon small samples in some of the occlusal groups, must be tested at least by longitudinal studies and possibly by experimentation.