Effect of rapid maxillary expansion on skeletal, dental, and nasal structures: a postero-anterior cephalometric study. (17/289)

The purpose of this study was to compare the transverse dimensions of skeletal, dental, and nasal structures of a group of patients with maxillary narrowness before and after rapid maxillary expansion (RME) with an untreated control group using postero-anterior (PA) cephalometric radiographs. The material consisted of PA cephalograms of 25 children with a posterior crossbite (mean age 13 years 4 months), and 25 age- and sex-matched controls (mean age 13 years 11 months). Both groups consisted of 20 females and five males. Thirty-four reference points were digitized using the Dentofacial Planner software program. The 17 variables studied consisted of six skeletal, four dental, and seven intra-nasal linear measurements. Student's t-tests were used to compare the differences between the groups, and the effect of RME on skeletal, dental, and nasal structures. RME produced small, but statistically significant changes in maxillary width, upper and lower molar widths, the width between upper central incisor apices, and intra-nasal width. When compared with previous studies, the changes observed were similar for patients of a similar age group, but less than reported for a younger population. There is some evidence that the pattern of expansion produced by RME will vary depending on the age and maturity of the subject.  (+info)

Craniofacial growth of immature rats following administration of vincristine and doxorubicin. (18/289)

The aim of the present study was to investigate the possible short-term effect of two anti-neoplastic drugs, vincristine and doxorubicin, on the craniofacial skeleton in young rats. On the basis of findings from pilot experiments, one dose of 0.0375 mg/kg vincristine or 1.0 mg/kg doxorubicin was given parenterally to inbred Long-Evans/Turku rats at 10 or 30 days of age, and followed up until 30 or 50 days, respectively. Some 30-day-old rats received two additional doses of the drugs, 3 and 6 days after the first injection. Controls were given physiological saline. A total of 310 rats were used: 40 for the pilot study, 180 medicated, and 90 control animals for the experiment itself. The weights of the rats were recorded, a number of craniofacial dimensions were measured, and the neurocranial volume determined in the case of the most severely affected rats. The weight gain of the younger rats was retarded, as was that of the older rats that received repeated drug injections. Most dimensions of the craniofacial skeleton were significantly smaller in the vincristine-treated young animals, and following multiple injections of vincristine or doxorubicin also in the older ones when compared with the controls. Contrary to the general pattern, the measurements of the foramen magnum increased in the older rats, a feature associated with the decrease in brain cavity volume observed in those that received vincristine. These findings indicate that anti-neoplastic agents can have a short-term adverse effect on the craniofacial growth and that the morphological changes are differential, rather than uniform.  (+info)

A case of anterior open bite developing during adolescence. (19/289)

Imaging studies have reported on the relationship between temporomandibular joint (TMJ) degeneration and facial deformity. These studies have suggested that mandibular growth is affected by TMJ degeneration, resulting in altered skeletal structure as mandibular retrusion. However, there are very few longitudinal case reports on TMJ osteoarthrosis (OA). Progressive open bite occurred in an adolescent patient with TMJ OA. Cephalometric analysis showed a downward and backward rotated mandible, and a labial inclination of the upper incisor. Magnetic resonance imaging showed internal derangement without reduction and erosion in the right and the left condyles. Although the cause of open bite is unclear in this case, tongue thrusting, and internal derangements in the temporomandibular joint were suspected as causes of the open bite.  (+info)

Dentoskeletal morphology in children with juvenile idiopathic arthritis compared with healthy children. (20/289)

The aim of this study was to evaluate the dentoskeletal relationships in children with juvenile idiopathic arthritis (JIA) compared to healthy children without significant differences in relation to age and sex, by means of lateral cephalometric radiographs. Cephalometric, as well as dental panoramic radiographs were taken of 66 JIA children (27 males and 39 females; age range: 6-19 years; mean age: 11.9 years). The control group consisted of 37 healthy children unaffected by JIA seeking orthodontic treatment, with Class I occlusion (17 males and 20 females; age range: 7.5-17 years; mean age: 11.9 years). All cephalometric landmarks were identified and digitized, and calculations were performed by means of a computerized cephalometric system. The cephalometric findings indicated a tendency towards retrognathism with a short mandible. The lower facial height was increased and the growth pattern of the face was biased towards the vertical direction (clockwise, i.e. with a tendency to open bite) and the interincisal angle was less in the JIA children compared to the healthy children. These findings were in general more pronounced by the JIA children with polyarticular type of the disease as well as with affected condyles. Our study indicated that the dentoskeletal morphology in children with JIA presented some special characteristics when compared to healthy children, which could be attributed to the effects of the disease.  (+info)

Rapid palatal expansion in mixed dentition using a modified expander: a cephalometric investigation. (21/289)

The aims of this investigation were to cephalometrically study the short-term skeletal and dental modifications induced by rapid palatal expansion in a sample of 20 patients (10 male, 10 female), aged 6-10 years (mean age 8 years) in mixed dentition with a uni- or bilateral posterior crossbite, a mild skeletal Class II malocclusion, and an increased vertical dimension (FMA, SN/\GoGn), and to compare them with an untreated matched control group of 20 subjects (10 male and 10 female), mean age 8 years. Cephalometric analysis showed that the maxilla displayed a tendency to rotate downwards and backward, resulting in a statistically significant increase of the SN/\PP angle (T0 = 9*95 degrees, T1 = 11*60 degrees, P < 0*01) and the SN-ANS linear value (T0 = 49*50 mm, T1 = 51*10 mm, P < 0*05). In addition, there was a statistically significant alteration of the anterior total facial height N-Me (T0 = 113*15mm, T1 = 114*15 mm, P < 0*05) and for the dental upper molar measurement U6-PP (T0 = 19*70 mm, T1 = 20*30 mm, P < 0*05). The small alterations found in the anterior total facial height and in the sagittal angles agree with previous studies, and suggest that RPE can be also used in subjects with a tendency to vertical growth and a skeletal Class II malocclusion.  (+info)

The mid-palatal suture in young adults. A radiological-histological investigation. (22/289)

The aim of the present study was to analyse which histological-histomorphometric findings correspond to a radiologically diagnosed open (group I) or closed mid-palatal suture (group II) on occlusal radiographs. For this purpose, 30 radiological regions of interest (rROI) from specimens obtained from 10 subjects ranging in age from 18 to 38 years were evaluated, and compared with the suture morphology, mean sutural width, and degree of suture closure on stained sections (3/rROI). The results showed that whether or not a radiologically visible suture can be classified as 'open' depends predominantly on the main oronasal suture course in relation to the X-ray path, rather than on factors such as suture width and degree of obliteration. The mean sutural width was 231 microns in group I (n = 10 rROI) and 201 mu in group II (n = 20 rROI). The degree of obliteration in relation to the total oronasal suture length was 0.45 in group I and 1.30 per cent in group II. No significant differences were found between the corresponding parameters of the two groups. The term 'suture obliteration' or 'fusion' should be avoided if a suture is radiologically not visible, since in 11 of the 20 rROI in which the suture was not visible no obliteration was recorded morphometrically.  (+info)

A longitudinal evaluation of craniofacial growth in a patient with Kabuki make-up syndrome: a case report. (23/289)

The purpose of this investigation was to evaluate the craniofacial growth of a patient diagnosed with Kabuki make-up syndrome (KMS). Craniofacial growth was assessed by analysing lateral cephalometric radiographs with an interval of 12-15 months. They were taken from 6 years 9 months to 14 years 2 months. Angular and linear measurement analyses of the craniofacial complex showed a hypoplastic maxilla and a constricted maxillary basal arch width. The mandibular size was relatively large and had started to increase from 13 years 4 months. This resulted in a prognathic face caused by forward growth of the mandible and insufficient growth of the maxilla. The skeletal pattern was Class III. Open bite morphology with a steep mandibular plane (SN-MP), a relatively short ramus, and a large gonial angle were also observed. In this subject, the facial dysmorphism found in the maxilla and mandible may have been influenced by several factors. Connective tissue disorder, macroglossia, lower tongue posture, and tongue thrust swallowing have been identified as possible aetiological factors that may determine dysmorphism in the craniofacial complex in this KMS patient.  (+info)

Craniofacial variability and its relationship to disharmony of the jaws and teeth. (24/289)

Examination of size and shape changes in the skulls of growing dogs and related canidae indicates that dental irregularity and jaw disharmony result when the growth pattern of the skull as a whole departs too widely from the norm.  (+info)