Soft-tissue Compensation Research Articles

Soft tissue compensation evaluation in patients with facial asymmetry using cone-beam computed tomography combined with 3D facial photographs

ObjectivesThis study aimed to evaluate bilateral soft tissue, hard and soft-tissue thickness at various anatomical levels in patients with facial asymmetries. Moreover, we attempted to find out correlation between soft-tissue compensation and severity of asymmetry by using cone-beam computed tomography (CBCT) combined with 3D facial photographs. Study designBased on menton deviation (MD), twenty-four subjects were divided into: mild-asymmetry group (n=12) and moderate-to-severe-asymmetry group (n = 12). CBCT images were superimposed with 3D facial photographs. Distance from the midsagittal plane to the outermost point of soft-tissue and hard-tissue were measured and calculated soft-tissue thickness. Comparison of soft-tissue thickness between deviated and contralateral side at any anatomical levels were performed within group, and correlation between bilateral soft-tissue thickness subtractions (soft-tissue compensation) and MD values was evaluated. ResultsWithin group, Soft- and hard-tissue distances were greater in deviated side than contralateral side at any levels. In moderate-to-severe group, significant differences were found at gonion and body of mandible level, whereas soft-tissue thickness was only found to be higher on deviated side at the level of mandibular ramus. Soft tissue compensation was negatively correlated with MD value at level of mandibular ramus (R = −0.5, P < 0.05). ConclusionsAsymmetry was found to be larger in the lower third of the face and was notably remarkable in the moderate-to-severe group. Soft-tissue thickness was thicker on the deviated side of the mandibular ramus. Thus, the soft-tissue compensation seems to be minimized in patients with more severe asymmetry.

Cephalometric Assessment of Differences in Soft Tissue and Dental Compensation in Skeletal Class II Div 1 Malocclusion.

This study was conducted to evaluate the differences in soft tissue as well as dental compensation in skeletal Class II div 1 malocclusion. The study sample consists of pre-treatment lateral cephalograms of 100 subjects of both gender having skeletal Class II and dental Class II div 1 malocclusion visiting the Department of Orthodontics and Dentofacial Orthopaedics, Bharati Vidyapeeth Dental College, and Hospital Navi Mumbai. Cephalograms of the subjects fulfilling the inclusion criteria were included in this study. This research was conducted to assess dental and soft tissue compensation in skeletal Class II div 1 malocclusion and comparative assessment of lip prominence measured from two soft tissue vertical reference lines. The 100 subjects selected randomly out of which 44 men and 56 women, age ranging from 18 to 35 years. ARNETT'S method and PROFFIT'S method showed statistically significant as P < 0.0001. PROFFIT'S method and LEGAN-BURSTONE'S method showed statistically significant as P < 0.0001.

Soft tissue thickness in Brazilian adults of different skeletal classes and facial types: A cone beam CT - Study.

The aim in this study was to evaluate the influence of skeletal class, facial type, and sex on soft tissue thickness (STT) of the craniofacial midline in a Brazilian subpopulation. Thus, 121 cone beam computed tomography (CBCT) scans (54 males and 67 females, age 21 to 40yrs) composed the study sample. Patients were classified according to skeletal class (class I, II, and III) and facial type (brachycephalic, mesocephalic, and dolichocephalic), and STT was measured (mm) in 10 landmarks in the craniofacial midline for each CBCT scan. Multivariate analysis of covariance evaluated facial STT with regard to multiple independent variables (sex, age - covariate, facial type, and skeletal class). TEM and rTEM assessed the intra-examiner agreement. STT was significantly greater in males than in females for all regions measured (p<0.05), except for the pogonion-pogonion' landmark (p>0.05). In general, class III individuals had significantly thicker soft tissue in the maxilla - subspinale-subnasale', prosthion-labrale superius', and incision-stomion' regions, while class II subjects had thicker soft tissue in the infradentale-labrale inferius' mandibular landmark (p<0.05). Regarding facial type, dolichocephalic individuals showed significantly thicker soft tissue in the supramentale-supramentale' mandibular landmark, whereas brachycephalic subjects had thicker soft tissue in maxillary regions - prosthion-labrale superius' and incision-stomion' (p<0.05). rTEM values were below 5% for most landmarks, and all TEM values were below 1 mm. Skeletal class and facial type influence STT, showing a soft tissue compensation, with deeper soft tissue in areas with lower skeletal development, and/or where bone is positioned more posteriorly.

The use of three-dimensional evaluation in the management of a complex patient with mandibular fracture: a 5-year evaluation.

The aims of this study were to diagnose and evaluate a case of severe condylar fracture followed up over 5 years using three-dimensional imaging for soft tissue and hard tissue. The patient underwent reconstruction with an autogenous rib graft to correct the resorbed left condyle secondary to a previous fracture and to balance her facial asymmetry. Orthodontic treatment is ongoing to equilibrize the occlusion and dentofacial complex. A stereo-photogrammetric system (3dMDFace System) was used to capture the soft tissue image of the patient. In addition, a cone-beam computed tomography (Kodak 9500) was used for hard tissue acquisition. The resultant images were analyzed using Rapidform 6 (RP6) and 3dMDvultus three-dimensional software packages, for 3 time frames: before surgery (T1), 1 month after surgery (T2), and 8 months after surgery (T3). Using three-dimensional software to analyze the three-dimensional data, several findings were noted: (1) soft tissue compensation of the hard tissue deformity for the facial asymmetry was around 7 mm; (2) color mapping and histograms helped identify distinct facial differences represented by positive changes of the patient's face because of the mandible reconstruction at T1-T2 and the mandible moving to its normal position at T3-T4. Three-dimensional imaging provides more accurate information and virtual representation of the patient. This leads to better diagnosis and treatment planning. In addition, the preliminary results of this study showed supportive evidence for the use of rib grafts in children.

Maxillofacial growth after neck burn injury at a young age: an experimental study in the rabbit.

An experimental model was designed to define alterations in the normal mandibular growth process under the influence of postburn neck contractures. Additionally, this craniofacial growth model was used to compare two early treatment modalities of neck burns in their capability to minimize contracture and hence allow for normal mandibular growth and development. Growth implies increase in size as well as change in shape and position. These three aspects of growth were defined accordingly to Björk as rotations. The intramatrix rotation expresses the change in mandibular shape, and the matrix rotation expresses the change in mandibular position relative to surrounding structures. The total rotation expresses both, and together with the measurement of the mandibular length, they represent the increase in mandibular size. Thirty-two 7-week-old rabbits were divided at random in four groups of eight rabbits each and randomized for selection for the 14 operation days defined as t = 0: Group A: controls to define normal mandibular growth Group B: untreated third-degree neck burns Group C: third-degree neck burns treated by a full-thickness skin graft Group D: third-degree neck burns treated by a myocutaneous flap All animals underwent placement of two bone markers in the maxilla. With biweekly intervals, standardized lateral skull roentgenographs were taken until the rabbits reached the age of 21 weeks. In this time period, major growth accelerations including the pubertal growth spurt took place. By the use of 13 reference points and 7 reference lines, rotations and distances were calculated. Statistical analysis of the data was performed. The results show that the normal mandibular length was unaffected in all groups. There were no statistically significant changes in matrix, intramatrix, and total rotations of the mandible and the maxilla. There was a statistically significant difference in the displacement of the mandibular reference point between all groups, suggesting a variable degree of normal backward skull rotation, namely, due to group B. Explanations to be considered concerning the fact that the only minor differences were found in group B: 1. Drawbacks of the animal model: differences in skin texture, postnatal mandibular growth, and head position compared with those of humans. 2. Other functional adaptation mechanisms such as changes in head position, which are recruited at first in adapting to disturbances of homeostasis, were not measured. Soft-tissue compensation probably has overcome major bony deformations. Nevertheless, some drawbacks of the model can be viewed as ideal concerning treatment of neck burns.(ABSTRACT TRUNCATED AT 250 WORDS)

A contact method for the assessment of ultrasonic velocity and broadband attenuation in cortical and cancellous bone

A portable system using a direct contact for the measurement of ultrasonic velocity and broadband attenuation in bone is described (contact ultrasonic bone analyser, CUBA). Soft-tissue compensation is performed using an ultrasonic pulse-echo technique. CUBA has been successfully validated using reference materials, the precision of velocity and broadband attenuation measurements being typically 0.2% and 0.5% respectively. The clinical reproducibility has been assessed on the equine third metacarpal bone. The reproducibility of velocity measurement is typically 0.5% for cortical bone and 1% for cancellous bone. For broadband attenuation the reproducibility is typically 7% for cortical bone and 6% for cancellous bone. The lower reproducibility of the attenuation data is attributed to the high sensitivity to variations in the material properties of bone with small changes in transducer positioning. Coupling difficulties through an intact equine coat have been overcome and the system may now be assessed in the clinical environment, in both human and animal populations.

The Trilogy of the “Triad of O'Donoghue” in the Knee and Its Analogy to the TMJ Derangement

An attempt has been made to describe the similarities between the pathological injury "Triad of O'Donoghue" in the knee and its analogous equivalent in the internal derangements of the temporomandibular joint (internal derangements). Because of the similarities between these internal derangements and the treatment they require, TM joint internal derangements should be reimbursed as a medical problem by insurance carriers as internal derangements in the knee are reimbursed. A description of the anatomical, physiological, and arthro-kinomatics of these two synovial joints has been done to further point out that they both operate by the same physiological principles, and therefore should be treated as similar dysfunctions. Treatment should be rendered to the TM joint, as in the knee, from an orthopedic viewpoint. This requires that treatment to the TM joint include a cooperative rehabilitative team approach. This team approach encompasses medical and dental cooperative care to stabilize the joint and secondarily control joint related soft tissue compensation and pain.

Genucom Knee Analysis System: An evaluation of the soft tissue compensation procedure

Genucom Knee Analysis System: An evaluation of the soft tissue compensation procedure