• Title/Summary/Keyword: plastic rotation

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Three Rotational Variables in Osseous Genioplasty (절골 턱끝성형술에 있어 3가지 축에 따른 회전적 관계의 활용)

  • Lee, Hyun-Tae;Kim, Yong-Ha;Kim, Tae-Gon;Lee, Jun-Ho
    • Archives of Plastic Surgery
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    • v.38 no.3
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    • pp.279-286
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    • 2011
  • Purpose: Chin is located in a prominent position, and is important to balance and harmony of the face. Genioplasty is widely performed with patients' high satisfaction, yet being relatively simple procedure. Recently in analysis of dentofacial trait, three rotational variables of yaw, pith, and roll are considered with three translational variables (forward/backward, up/down, right/left). And we could correct chin deformity effectively by applying the three rotational variables with three translational variables in genioplasty. Methods: Twenty-eight patients who have chin deformity underwent osseous genioplasty. Preoperative photography, facial three dimensional computed tomography, and cephalography were taken while chin deformities were accessed. The chin deformity was classified into four categories; macrogenia, microgenia, asymmetric chin deformity, and combined chin deformity groups. According to the nature of chin deformities and the patients' desire, preoperative plans were formulated, in consideration of three rotational variables and translational variables. Through intraoral approach, anterior mandible was exposed in the subperiosteal plane between the mental foramens and beneath the mental foramens. In the anterior mandible, vertical and horizontal grid lines with 5 mm intervals were marked to confirm the spatial location of osteomized bone segment after osteotomy. Chin repositioning was done in consideration of axial rotation and planar translation. Results: Most of the patients had achieved satisfactory results with few complications. By considering the three rotational variables, it was possible to make the chin repositioning effectively. One of the patients complained about insufficient chin correction. In other case, persistent sensory impairment around chin was observed. Conclusion: In conclusion, it is worthwhile to apply preoperative analysis and operative procedures in consideration of a three rotational variables with three translational variables in genioplasty.

Reconstruction of Various Perinasal Defects Using Facial Artery Perforator-Based Nasolabial Island Flaps

  • Yoon, Tae Ho;Yun, In Sik;Rha, Dong Kyun;Lee, Won Jai
    • Archives of Plastic Surgery
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    • v.40 no.6
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    • pp.754-760
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    • 2013
  • Background Classical flaps for perinasal defect reconstruction, such as forehead or nasolabial flaps, have some disadvantages involving limitations of the arc of rotation and two stages of surgery. However, a perforator-based flap is more versatile and allows freedom in flap design. We introduced our experience with reconstruction using a facial artery perforator-based propeller flap on the perinasal area. We describe the surgical differences between different defect subtypes. Methods Between December 2005 and August 2013, 10 patients underwent perinasal reconstruction in which a facial artery perforator-based flap was used. We divided the perinasal defects into types A and B, according to location. The operative results, including flap size, arc of rotation, complications, and characteristics of the perforator were evaluated by retrospective chart review and photographic evaluation. Results Eight patients were male and 2 patients were female. Their mean age was 61 years (range, 35-75 years). The size of the flap ranged from $1cm{\times}1.5cm$ to $3cm{\times}6cm$. Eight patients healed uneventfully, but 2 patients presented with mild flap congestion. However, these 2 patients healed by conservative management without any additional surgery. All of the flaps survived completely with aesthetically pleasing results. Conclusions The facial artery perforator-based flap allowed for versatile customized flaps, and the donor site scar was concealed using the natural nasolabial fold.

The usefulness of intermolar traction wiring for restoration of maxillary & mandibular dental arch in facial bone fracture (안면골 골절에서 상하악 치열궁 복원을 위한 양측 대구치간 철사견인술의 유용성)

  • Jeong, Jae Ho;Shin, Seung Kyu;Lee, Jun Ho;Kim, Yong Ha
    • Archives of Plastic Surgery
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    • v.36 no.1
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    • pp.56-60
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    • 2009
  • Purpose: Palatal fracture and mandible fracture result in instability of dental arch. Because they divide the maxillary and mandibular alveolus sagittally and / or transversely and comminute the dentition, they permit rotation of dental alveolar segments and significantly increase the potential for fracture malalignment, complicating fracture treatment. Previous treatment of palatal fracture consisted of palatal splint application and rigid palatal vault stabilization. This procedure result in patient's oral discomfort and removal of palate and screw. Mandible fracture often results in malocclusion due to widening of posterior aspect of dental arch. So we introduce more simple method using intermolar traction wiring, which can protect the widening of dental arch and rotation of dental alveolar segment. Methods: Arch bar and intermolar traction wiring with wire 1 - 0, or 2 - 0 was applied. After exposure of fracture line, neutrooclusion was maintained with intermaxillary fixation. And then open reduction & internal fixation on maxillary fracture line, commonly maxillary buttress, alveolar ridge, pyriform aperture except palatal vault or mandibular fracture line. After 1 week, intermolar traction wiring was removed. We checked occlusion and postoperative radiologic finding. Results: From June of 2007 to October of 2007, 10 patient, who have maxillary fracture with palatal fracture and mandible fracture, underwent open reduction & internal fixation with intermolar traction wiring. All have satisfactory occlusion and there were no complication, like gingiva disease, mouth opening impairment and nonunion. Conclusion: The intermolar traction wiring accompany open reduction and internal fixation can be alternative method for restoration of dental arch in facial bone fracture.

Reconstruction of Necrosis Following Total Knee Replacement Arthroplasty (슬관절 전치환술 후 발생한 피부 괴사부의 재건)

  • Ahn, Hee Chang;Lim, Young Soo;Kim, Chang Yeon;Hwang, Weon Joong
    • Archives of Plastic Surgery
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    • v.32 no.1
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    • pp.93-99
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    • 2005
  • In spite of proper maneuver of total knee replacement arthroplasty, some patients suffer from skin necrosis just above the implant. From Mar. 2000 to Jan. 2004, the authors performed reconstruction of knee skin defects after total knee replacement athroplasty. Total 6 cases of flap surgery were performed and patients ranged between 43-years-old to 82-years-old. Rectus femoris perforator based reversed adipofascial flaps were used in 2 cases, medial gastrocnemius muscular island flaps were used in 2 cases and sural artery based on adipofascial rotation flap was used in 1 case. One patient with extended necrosis underwent reconstruction with dual flaps of sural artery based adipofascial rotation flap and medial gastrocnemius muscular island flap. There were no distinctive complication needing additional procedure in all cases during the long term follow up. Reconstruction of necrosis following total knee replacement arthroplasty had several characteristics different from simple knee defect. The patients might have the history of long term steroid usages, excessive skin tension due to implants, underlying disease such as diabetes, rheumatoid disease, and etc. In addition, the early ambulation is mandatory in these patients of total knee replacement arthroplasty. With regards to these special considerations, a single stage and reliable operation must be needed. The authors introduce various reconstruction methods and algorithm that may aid easy decision making.

Cephalic lateral crural advancement flap

  • Bulut, Fuat
    • Archives of Plastic Surgery
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    • v.48 no.2
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    • pp.158-164
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    • 2021
  • Background In lower lateral cartilage (LLC) surgery, cephalic trimming poses risks for the collapse of the internal and external nasal valves, pinched nose, and drooping deformity. The cephalic lateral crural advancement (CLCA) technique presented herein was aimed at using a flap to increase nasal tip rotation and support the lateral crus, in addition to the internal and external nasal valves, by avoiding grafts without performing excision. Methods This study included 32 patients (18 female and 14 male) and the follow-up period for patients having undergone primer open rhinoplasty was 12 months. The LLC was elevated from the vestibular skin using the CLCA flap. A cephalic incision was performed without cephalic trimming. Two independent flaps were formed while preserving the scroll ligament complex. The CLCA flap was advanced onto the lower lateral crus while leaving the scroll area intact. The obtained data were analyzed retrospectively. Results The mean age of the patients was 31.6 years (range, 20-51 years). The Rhinoplasty Outcome Examination scores after 12 months varied from 90 to100 points, and 93% of patients reported perfect satisfaction. At a 1-year follow-up, the patients' nasal patency (visual analogue scale) rose from 4.56±1.53 (out of 10) to 9.0±0.65 (P<0.001). Conclusions The CLCA flap led to better nasal tip definition by protecting the scroll area, increasing tip rotation, and supporting the internal and external nasal valves without cephalic excision.

The effect of the tongue in groove technique on the nasolabial angle and nasal tip projection

  • Khabir, Fatemeh;Sezavar, Mehdi;Bohluli, Behnam;Mesgarzadeh, Vahid;Tavakoli, Hamidreza
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.42
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    • pp.19.1-19.4
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    • 2020
  • Background: The tongue in groove technique (TIG) is a useful technique for the correction of the nasal tip projection and the nasolabial angle. The purpose of this study was to determine the utility of this technique for nasal tip rotation and projection correction in the Iranian society. Methods: This is a retrospective clinical trial study of 20 patients undergoing open septo-rhinoplasty using TIG technique from January 2017 to August 2019 at the oral and maxillofacial unit of Bu Ali Hospital and private sector. Preoperative and postoperative profile view photographs were compared to assess the changes in tip projection and rotation. Results: Fifteen patients (75%) had normal angular size, and 5 of them (25%) were not within the normal range after the surgery. The Fisher exact test showed that this success was statistically significant (P = 0.006). Ten patients (50%) had normal projection size, postoperatively. The Fisher exact test showed that this effect was statistically significant (P < 0.01) Conclusion: The study demonstrated the benefit of TIG on the correction of nasal tip projection and rotation.

Unexpected postoperative atlantoaxial rotatory subluxation after excision of melanocytic nevi of the head and neck in older children: two case reports and literature review

  • Jiwon Kang;Byung Jun Kim
    • Archives of Craniofacial Surgery
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    • v.25 no.2
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    • pp.85-89
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    • 2024
  • Postoperative atlantoaxial rotatory subluxation (AARS) is a rare complication that develops almost exclusively in children following oropharyngeal and otologic surgeries, proposing that oropharyngeal inflammatory responses and excessive head rotation are responsible factors. However, there have been no reports of AARS after excision of a nevus on the head and neck. Here, we present two cases of AARS following limited head rotation during simple nevus excision. Patient 1, a 9-year-old girl, complained of neck pain and limited range of motion after excision of the nevus on the neck. After 2 months, computed tomography and magnetic resonance imaging finally revealed AARS with a ruptured transverse atlantal ligament. A month of halo traction was required for the treatment. Patient 2, an 11-year-old girl, presented with immediate pain and limited neck extension after tissue expander insertion under the upper chest and excision of the nevus on her left cheek. The diagnosis was promptly made using cervical spine radiography. A cervical collar was applied for 1 month. Both patients recovered without any complications after treatment. This report highlights the importance of suspicion for AARS after surgery regardless of surgical duration or amount of head rotation.

Determination of earthquake safety of RC frame structures using an energy-based approach

  • Merter, Onur;Ucar, Taner;Duzgun, Mustafa
    • Computers and Concrete
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    • v.19 no.6
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    • pp.689-699
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    • 2017
  • An energy-based approach for determining earthquake safety of reinforced concrete frame structures is presented. The developed approach is based on comparison of plastic energy capacities of the structures with plastic energy demands obtained for selected earthquake records. Plastic energy capacities of the selected reinforced concrete frames are determined graphically by analyzing plastic hinge regions with the developed equations. Seven earthquake records are chosen to perform the nonlinear time history analyses. Earthquake plastic energy demands are determined from nonlinear time history analyses and hysteretic behavior of earthquakes is converted to monotonic behavior by using nonlinear moment-rotation relations of plastic hinges and plastic axial deformations in columns. Earthquake safety of selected reinforced concrete frames is assessed by using plastic energy capacity graphs and earthquake plastic energy demands. The plastic energy dissipation capacities of the frame structures are examined whether these capacities can withstand the plastic energy demands for selected earthquakes or not. The displacements correspond to the mean plastic energy demands are obtained quite close to the displacements determined by using the procedures given in different seismic design codes.

Finite Element Analysis for Plastic Large Deformation and Anisotropic Damage

  • Nho, In-Sik;Yim, Sahng-Jun
    • Journal of Hydrospace Technology
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    • v.1 no.1
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    • pp.111-124
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    • 1995
  • An improved analysis model for material nonlinearity induced by elasto-plastic deformation and damage including a large strain response was proposed. The elasto-plastic-damage constitutive model based on the continuum damage mechanics approach was adopted to overcome limitations of the conventional plastic analysis theory. It can manage the anisotropic tonsorial damage evolved during the time-independent plastic deformation process of materials. Updated Lagrangian finite element formulation for elasto-plastic damage coupling problems including large deformation, large rotation and large strain problems was completed to develop a numerical model which can predict all kinds of structural nonlinearities and damage rationally. Finally a finite element analysis code for two-dimensional plane problems was developed and the applicability and validity of the numerical model was investigated through some numerical examples. Calculations showed reasonable results in both geometrical nonlinear problems due to large deformation and material nonlinearity including the damage effect.

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Repair of Unilateral Cleft Lip and Nose: Mulliken's Modification of Rotation Advancement (편측 구순열비의 교정술: Rotation Advancement 원칙에 근거한 Mulliken의 방법)

  • Jung, Young-Soo;Lee, Gyu-Tae;Jung, Hwi-Dong;Mulliken, John B.
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.34 no.2
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    • pp.133-139
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    • 2012
  • This is a review regarding Mulliken's Modification using the Millard rotation-advancement principle for the repair of unilateral complete cleft lip and nasal deformity. All patients underwent prior labionasal adhesion and dentofacial orthopedics with a pin-retained (Latham) appliance used for infants with a cleft of the lip and palate. Technical variations concerning the operation are described. A high rotation and releasing incision in the columella lengthens the medial labial element and produces a symmetric prolabium with minimal transgression of the upper philtral column through the advancement flap. The orbicularis oris muscle is everted, from caudad to cephalad, to form the philtral ridge. A minor variation of unilimb Z-plasty is used to level the cleft side of Cupid's bow handle, and cutaneous closure proceeds superiorly from this junction. The dislocated alar cartilage is visualized though a nostril rim incision and suspended to the ipsilateral upper lateral cartilage. Symmetry of the alar base is addressed in three dimensions, including maneuvers to position the deviated anterior-caudal septum, configure the sill, and efface the lateral vestibular web. The authors believe the technical refinements described herein contribute favorably to the outcome of repair regarding unilateral cleft lip and nasal distortion.