scholarly journals Occlusal Cant and Its Challenges – A Review

2021 ◽  
Vol 10 (33) ◽  
pp. 2835-2840
Author(s):  
Renuka Rao Talla
Keyword(s):  
Soft Tissue ◽  
Combination Treatment ◽  
Orthognathic Surgery ◽  
Anterior Segment ◽  
Skeletal Anchorage ◽  
Orthodontic Therapy ◽  
Satisfactory Outcome ◽  
Lateral Cephalograms ◽  
Wide Range ◽  
The Asymmetry

Asymmetries can be considered as a huge challenge for an orthodontist because of the complex mechanics and uncertainty in stability of treatment outcomes. Multifactorial nature of the asymmetry due to wide range has complicated the classification and determination of the cases. The aetiology can be classified as hereditary and environmental factors. The occlusal cant in patients can be evaluated by frontal photographs, lateral cephalograms, clinical assessment and a threedimensional imaging methods. Photographs can be used as one of the methods to evaluate the asymmetries of the soft tissue and also the cant of lips. In recent times with the aid of computers and different software’s like power point or keynote the use of reference lines with the software, facilitates in the analysis of the smile and the occlusal plane. The management of occlusal cant includes different treatment alternatives like orthognathic surgery, orthodontic therapy, or a combination treatment of both orthognathic surgery and orthodontic therapy. The surgical approach depends upon the awareness of the patient with the severity of cant and aesthetic problems as well as the jaw discrepancy in both vertical and sagittal directions. Orthognathic surgery creates an overall skeletal as well as soft tissue improvement including the lips. In cases with OC in anterior segment and deep - bite malocclusion a combination treatment is required. To reduce the anterior vertical height and to achieve more stable results intrusion of molars is considered using skeletal anchorage. The skeletal anchorage (miniscrews or miniplates) can be used for the correction of the cant in maxillary segment and the surgical treatment for correction of the asymmetry of the face like sagittal split osteotomy, ramus osteotomy etc. can be carried out. To achieve satisfactory outcome the clinician must examine and find the etiological factors and proper treatment planning has to be carried out based on the type of occlusal cant such that the outcome shows aesthetic smile along with good facial symmetry. KEY WORDS Occlusal Cant, Facial Asymmetry, Skeletal Asymmetry, Cant.

The Benefits of Post-surgical Orthodontic Treatment

1994 ◽  
Vol 21 (3) ◽  
pp. 265-274 ◽  
Author(s):  
R. T. Lee
Keyword(s):  
Soft Tissue ◽  
Orthognathic Surgery ◽  
Orthodontic Treatment ◽  
Tooth Movement ◽  
Treatment Time ◽  
Overall Treatment Time ◽  
Orthodontic Therapy ◽  
Clinical Benefits

Orthodontic therapy is best carried out in a normal skeletal and soft tissue environment. In patients requiring orthognathic surgery, it is suggested that there are advantages in correcting the skeletal and soft tissue elements as early as possible, and to orthodontically control the occlusion post-operatively. This results in a shorter overall treatment time due to more biologically favourable tooth movement, more predictable occlusal results and better management by the orthodontist. The clinical benefits of post-operative orthodontics are outlined.

scholarly journals Comparison of Dentoskeletal and Soft Tissue Changes Between Tooth-Borne and Tooth-Bone-Borne Hybrid Nonsurgical Rapid Maxillary Expansions in Adults: A Retrospective Observational Study

2021 ◽  
Author(s):  
Jung-Sub An ◽  
Bo-Yeon Seo ◽  
Sug-Joon Ahn
Keyword(s):  
Soft Tissue ◽  
Vertical Dimension ◽  
Skeletal Anchorage ◽  
Maxillary Expansion ◽  
Sex Distribution ◽  
Number Of Patients ◽  
Lateral Cephalograms ◽  
Expansion Protocol ◽  
Tissue Changes ◽  
Soft Tissue Changes

Abstract Background Despite the gradual increase in the use of rapid maxillary expansion (RME), specifically RME with the aid of skeletal anchorage in adults, there have been no reports comparing dentoskeletal and soft tissue changes between nonsurgical tooth-borne and tooth-bone-borne RMEs in adults. This study aimed to analyse differences in dentoskeletal and soft tissue changes between tooth-borne and tooth-bone-borne RMEs using a similar appliance design and the same expansion protocol in adult patients. Methods Twenty-one patients with tooth-borne expansion (a conventional expansion screw with two premolars and two molar bands for dental anchorage [T-RME]) and the same number of patients with tooth-bone-borne hybrid expansion (a conventional expansion screw with two premolar and two molar bands for dental anchorage and four mini-implants in the palate for skeletal anchorage [H-RME]) were included. Dentoskeletal and soft tissue variables at pretreatment (T1) and after expansion (T2) were measured using posteroanterior and lateral cephalograms and frontal photographs. The sex distribution of the two groups was analysed using the chi-square test, and the change after RME in each group was evaluated using the Wilcoxon signed-rank test. Differences in pretreatment age, expansion duration, post-expansion duration, and dentoskeletal and soft tissue changes after RME between the two groups were determined using the Mann–Whitney U test. Results There were no significant differences in the expansion protocol, pretreatment conditions, and sex distribution between the two groups. Despite similar degrees of dental expansion at the crown level between the two groups, H-RME induced increased skeletal and parallel expansion of the maxilla compared to T-RME. After expansion, H-RME demonstrated increased forward displacement of the maxilla without significant changes in the vertical dimension, while T-RME exhibited increased backward displacement of the mandible, increased vertical dimension, and decreased overbite. Both groups showed significant retroclination and extrusion of the maxillary incisors without significant intergroup differences. There were no significant soft tissue changes between the two groups. Conclusion This study suggests that using skeletal anchorage in RME may induce increased skeletal and parallel expansion of the maxilla without significant effects on the vertical dimension.

scholarly journals Predicting soft tissue changes after orthognathic surgery: The sparse partial least squares method

2019 ◽  
Vol 89 (6) ◽  
pp. 910-916 ◽  
Author(s):  
Hee-Yeon Suh ◽  
Ho-Jin Lee ◽  
Yun-Sic Lee ◽  
Soo-Heang Eo ◽  
Richard E. Donatelli ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Prediction Model ◽  
Least Squares ◽  
Partial Least Squares ◽  
Orthognathic Surgery ◽  
Prediction Algorithm ◽  
Wide Range ◽  
Tissue Changes ◽  
Input Variables ◽  
Soft Tissue Changes

ABSTRACT Objectives: To develop a prediction algorithm for soft tissue changes after orthognathic surgery that would result in accurate predictions (1) regardless of types or complexity of operations and (2) with a minimum number of input variables. Materials and Methods: The subjects consisted of 318 patients who had undergone the surgical correction of Class II or Class III malocclusions. Two multivariate methods—the partial least squares (PLS) and the sparse partial least squares (SPLS) methods—were used to construct prediction equations. While the PLS prediction model included 232 input variables, the SPLS method included a reduced number of variables generated by a handicapping algorithm via the sparsity control. The accuracy between the PLS and SPLS models was compared. Results: There were no significant differences in prediction accuracy depending on surgical movements, the sex of the subjects, or additional surgeries. The predictive performance with a reduced set of 34 input variables chosen using the SPLS method was statistically indistinguishable from the full set of variables with the original PLS prediction model. Conclusions: The prediction method proposed in the present study was accurate for a wide range of orthognathic surgeries. A reduced set of input variables could be selected through the SPLS method while simultaneously maintaining a prediction level that was as accurate as that of the original PLS prediction model.

scholarly journals Incisal and Soft Tissue Effects of Maxillary Premolar Extraction in Class II Treatment

2007 ◽  
Vol 77 (5) ◽  
pp. 808-816 ◽  
Author(s):  
Nevenka Tadic ◽  
Michael G. Woods
Keyword(s):  
Soft Tissue ◽  
Class Ii ◽  
Individual Response ◽  
Lower Lip ◽  
Fixed Appliance ◽  
Premolar Extraction ◽  
Class Ii Treatment ◽  
Nasolabial Angle ◽  
Lateral Cephalograms ◽  
Wide Range

Abstract Objective: This retrospective study was designed to show likely upper incisal and soft tissue lip changes accompanying Class II fixed appliance treatment with only two upper premolar extractions and to assess whether the lips, especially, are predictably and directly affected with such treatment. Materials and Methods: Pretreatment and posttreatment lateral cephalograms and study casts from 61 growing Class II patients (aged 11 to 18 years; 39 division 1 and 22 division 2) were assessed. Upper and lower lip curve depths, nasolabial angle, and upper incisal position and angulation were all assessed and compared with changes in other cephalometric variables. Results: A wide range of individual response in both lip and upper incisor behavior were noted. The observed soft tissue lip changes were most likely to be related to the preexisting morphology of the lips themselves, while upper incisal changes were mainly related to their own pretreatment positions and changes occurring with treatment in the underlying bony structures. Conclusion: Orthodontic treatment involving the extractions of only two upper premolars is likely to result in a wide range of variation in lip and upper incisor behavior. The preexisting soft tissue morphology is likely to be the greatest determinant of lip behavior.

scholarly journals Comparison of dentoskeletal and soft tissue changes between tooth-borne and tooth-bone-borne hybrid nonsurgical rapid maxillary expansions in adults: a retrospective observational study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jung-Sub An ◽  
Bo-Yeon Seo ◽  
Sug-Joon Ahn
Keyword(s):  
Soft Tissue ◽  
Vertical Dimension ◽  
Skeletal Anchorage ◽  
Maxillary Expansion ◽  
Sex Distribution ◽  
Number Of Patients ◽  
Lateral Cephalograms ◽  
Expansion Protocol ◽  
Tissue Changes ◽  
Soft Tissue Changes

Abstract Background Despite the gradual increase in the use of rapid maxillary expansion (RME), specifically RME with the aid of skeletal anchorage in adults, there have been no reports comparing dentoskeletal and soft tissue changes between nonsurgical tooth-borne and tooth-bone-borne RMEs in adults. This study aimed to analyse differences in dentoskeletal and soft tissue changes between tooth-borne and tooth-bone-borne RMEs using a similar appliance design and the same expansion protocol in adult patients. Methods Twenty-one patients with tooth-borne expansion (a conventional expansion screw with two premolars and two molar bands for dental anchorage [T-RME]) and the same number of patients with tooth-bone-borne hybrid expansion (a conventional expansion screw with two premolar and two molar bands for dental anchorage and four mini-implants in the palate for skeletal anchorage [H-RME]) were included. Dentoskeletal and soft tissue variables at pretreatment (T1) and after expansion (T2) were measured using posteroanterior and lateral cephalograms and frontal photographs. The sex distribution of the two groups was analysed using the chi-square test, and the change after RME in each group was evaluated using the Wilcoxon signed-rank test. Differences in pretreatment age, expansion duration, post-expansion duration, and dentoskeletal and soft tissue changes after RME between the two groups were determined using the Mann–Whitney U test. Results There were no significant differences in the expansion protocol, pretreatment conditions, and sex distribution between the two groups. Despite similar degrees of dental expansion at the crown level between the two groups, H-RME induced increased skeletal and parallel expansion of the maxilla compared to T-RME. After expansion, H-RME demonstrated increased forward displacement of the maxilla without significant changes in the vertical dimension, while T-RME exhibited increased backward displacement of the mandible, increased vertical dimension, and decreased overbite. Both groups showed significant retroclination and extrusion of the maxillary incisors without significant intergroup differences. There were no significant soft tissue changes between the two groups. Conclusion This study suggests that using skeletal anchorage in RME may induce increased skeletal and parallel expansion of the maxilla without significant effects on the vertical dimension.

Evaluation of 99mTc-Label led Vitamin K4 as an Agent for Testicular Imaging

1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan
Keyword(s):  
Soft Tissue ◽  
Room Temperature ◽  
Normal Subjects ◽  
Left Testis ◽  
Wide Range ◽  
Activity Ratios ◽  
The Right ◽  
Radioactivity Levels

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.

Assessment of Commercial Off-the-Shelf Tissue Adhesives for Sealing Military-Relevant Corneal Perforation Injuries

2021 ◽  
Author(s):  
Eric J Snider ◽  
Lauren E Cornell ◽  
Brandon M Gross ◽  
David O Zamora ◽  
Emily N Boice
Keyword(s):  
Intraocular Pressure ◽  
High Speed ◽  
Anterior Segment ◽  
Ocular Tissue ◽  
Corneal Tissue ◽  
Corneal Perforation ◽  
Tissue Adhesives ◽  
Open Globe ◽  
Wide Range ◽  
Commercial Off The Shelf

ABSTRACT Introduction Open-globe ocular injuries have increased in frequency in recent combat operations due to increased use of explosive weaponry. Unfortunately, open-globe injuries have one of the worst visual outcomes for the injured warfighter, often resulting in permanent loss of vision. To improve visual recovery, injuries need to be stabilized quickly following trauma, in order to restore intraocular pressure and create a watertight seal. Here, we assess four off-the-shelf (OTS), commercially available tissue adhesives for their ability to seal military-relevant corneal perforation injuries (CPIs). Materials and Methods Adhesives were assessed using an anterior segment inflation platform and a previously developed high-speed benchtop corneal puncture model, to create injuries in porcine eyes. After injury, adhesives were applied and injury stabilization was assessed by measuring outflow rate, ocular compliance, and burst pressure, followed by histological analysis. Results Tegaderm dressings and Dermabond skin adhesive most successfully sealed injuries in preliminary testing. Across a range of injury sizes and shapes, Tegaderm performed well in smaller injury sizes, less than 2 mm in diameter, but inadequately sealed large or complex injuries. Dermabond created a watertight seal capable of maintaining ocular tissue at physiological intraocular pressure for almost all injury shapes and sizes. However, application of the adhesive was inconsistent. Histologically, after removal of the Dermabond skin adhesive, the corneal epithelium was removed and oftentimes the epithelium surface penetrated into the wound and was adhered to inner stromal tissue. Conclusions Dermabond can stabilize a wide range of CPIs; however, application is variable, which may adversely impact the corneal tissue. Without addressing these limitations, no OTS adhesive tested herein can be directly translated to CPIs. This highlights the need for development of a biomaterial product to stabilize these injuries without causing ocular damage upon removal, thus improving the poor vision prognosis for the injured warfighter.

scholarly journals Quantification of assembly forces during creation of head-neck taper junction considering soft tissue bearing: a biomechanical study

Arthroplasty ◽  
2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Toni Wendler ◽  
Torsten Prietzel ◽  
Robert Möbius ◽  
Jean-Pierre Fischer ◽  
Andreas Roth ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Work Experience ◽  
Soft Tissues ◽  
Force Sensor ◽  
Biomechanical Study ◽  
Measuring System ◽  
Wide Range ◽  
Head Neck

Abstract Background All current total hip arthroplasty (THA) systems are modular in design. Only during the operation femoral head and stem get connected by a Morse taper junction. The junction is realized by hammer blows from the surgeon. Decisive for the junction strength is the maximum force acting once in the direction of the neck axis, which is mainly influenced by the applied impulse and surrounding soft tissues. This leads to large differences in assembly forces between the surgeries. This study aimed to quantify the assembly forces of different surgeons under influence of surrounding soft tissue. Methods First, a measuring system, consisting of a prosthesis and a hammer, was developed. Both components are equipped with a piezoelectric force sensor. Initially, in situ experiments on human cadavers were carried out using this system in order to determine the actual assembly forces and to characterize the influence of human soft tissues. Afterwards, an in vitro model in the form of an artificial femur (Sawbones Europe AB, Malmo, Sweden) with implanted measuring stem embedded in gelatine was developed. The gelatine mixture was chosen in such a way that assembly forces applied to the model corresponded to those in situ. A study involving 31 surgeons was carried out on the aforementioned in vitro model, in which the assembly forces were determined. Results A model was developed, with the influence of human soft tissues being taken into account. The assembly forces measured on the in vitro model were, on average, 2037.2 N ± 724.9 N, ranging from 822.5 N to 3835.2 N. The comparison among the surgeons showed no significant differences in sex (P = 0.09), work experience (P = 0.71) and number of THAs performed per year (P = 0.69). Conclusions All measured assembly forces were below 4 kN, which is recommended in the literature. This could lead to increased corrosion following fretting in the head-neck interface. In addition, there was a very wide range of assembly forces among the surgeons, although other influencing factors such as different implant sizes or materials were not taken into account. To ensure optimal assembly force, the impaction should be standardized, e.g., by using an appropriate surgical instrument.

scholarly journals The Use of Anterior-Segment Optical-Coherence Tomography for the Assessment of the Iridocorneal Angle and Its Alterations: Update and Current Evidence

2021 ◽  
Vol 10 (2) ◽  
pp. 231
Author(s):  
Giacinto Triolo ◽  
Piero Barboni ◽  
Giacomo Savini ◽  
Francesco De Gaetano ◽  
Gaspare Monaco ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Intraocular Pressure ◽  
Clinical Relevance ◽  
Anterior Segment ◽  
Angle Closure ◽  
Current Evidence ◽  
Optical Coherence ◽  
Iridocorneal Angle ◽  
Wide Range

The introduction of anterior-segment optical-coherence tomography (AS-OCT) has led to improved assessments of the anatomy of the iridocorneal-angle and diagnoses of several mechanisms of angle closure which often result in raised intraocular pressure (IOP). Continuous advancements in AS-OCT technology and software, along with an extensive research in the field, have resulted in a wide range of possible parameters that may be used to diagnose and follow up on patients with this spectrum of diseases. However, the clinical relevance of such variables needs to be explored thoroughly. The aim of the present review is to summarize the current evidence supporting the use of AS-OCT for the diagnosis and follow-up of several iridocorneal-angle and anterior-chamber alterations, focusing on the advantages and downsides of this technology.

scholarly journals Radical treatment of severe open fractures of extremities by orthoplastic surgery: a 10-year retrospective study

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Zhao Yang ◽  
Chao Xu ◽  
Yong-Gang Zhu ◽  
Jun Li ◽  
Zi-Xiang Wu ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Infection Rate ◽  
Clinical Data ◽  
Open Fractures ◽  
Soft Tissue Reconstruction ◽  
Satisfactory Outcome ◽  
Tissue Damages ◽  
Tissue Reconstruction ◽  
Severe Soft Tissue

Abstract Objective This study aimed to retrospectively analyze clinical data of a series of patients with severe open fractures of extremities (Gustilo IIIb or IIIc), who achieved a satisfactory outcome through radical orthoplastic surgery, so as to provide a reference for determining the treatment of severe open fractures of extremities. Methods The clinical data of 41 consecutive patients with severe open fracture (Gustilo IIIb or IIIc) of the limb, who underwent successful surgical debridement, fixation, and soft tissue reconstruction in one stage between January 2008 and January 2019, were retrospectively reviewed. Postoperative indicators, including infection rate and union time, were acquired by a regular follow-up and analyzed. Results The mean (±SD) age of the patients was 38 ± 16 years. A total of 90 open fractures and severe soft tissue damages were analyzed. The soft tissue cover was achieved within 72 h. The overall rate of infection was 14.6% (6/41). Sex and the Mangled Extremity Severity Score were associated with infection. The median union time of 40 patients (one amputation) was 32 weeks. Conclusion The overall rate of infection exhibited a lower tendency in this study compared with previous studies on high-grade open fractures following a two-stage orthopedic approach. The consequence of infection rate and union time was similar to that in previous studies. These results indicated that the single-stage radical orthoplastic treatment was an effective and reliable option for reconstructing severe open fractures.

Sign in / Sign up

Export Citation Format

Share Document