Although 'small chin' is not a medical terminology, it is widely used between non-medical persons and even between medical doctors. But there are two kinds of diagnosis which look small chin. One is microgenia and another is micrognathia and because they called as a same name 'small chin', sometimes they are confused and result in suboptimal operation result. Microgenia can be treated by advancing sliding genioplasty, implant insertion and sometime by fat grafting. And micrognathia must be treated by orthognathic surgery theoretically. But many times advancing sliding genioplasty, implant insertion or fat grafting are applied to micrognathia. Sometime it was done by misdiagnosis but sometimes it is done intentionally to avoid orthognathic sugery which is considered as a complicated operation to the peoples who are unfamiliar to it. Sometimes it results in somewhat acceptable result, but it is not the best. So in this article, the author is going to discuss about the different results of orthgnathic surgery and camouflage sliding advancing genioplasty.
Chin ; Diagnostic Errors ; Genioplasty ; Humans ; Intention ; Mandible ; Orthognathic Surgery ; Transplants

When we establish treatment planning of facial asymmetry, we must predict each asymmetrical element that will be changed upon coronal, axial, sagittal plane. At the visual point, prediction of the change of coronal plane is most important. It is important difference between Rt. and Lt. mandibular angle belonging to posterior coronal plane, as well as anterior coronal plane, such as upper and lower incisor, or midline of chin point. Several methods for control bulk of mandibular angle are additional angle shaving after osteotomy, grinding contact area between proximal and distal segment for decrease the volume, or bone graft for increase the volume. But, at the point of bimaxillary surgery, transverse position of posterior maxilla is an important factor for control it. So, we would report transverse movement of posterior maxilla for decrease asymmetry on the posterior coronal plane of face, that is, asymmetry of mandibular angular portion.
Chin ; Facial Asymmetry* ; Incisor ; Maxilla* ; Orthognathic Surgery* ; Osteotomy ; Transplants

Although orthognathic surgery has been performed at the maxilla and the mandibular ramus to obtain a normal functional occulsion and aesthetic improvement of the face, deformities of the chin and disproportion of the soft tissue have been left. Mandibular set-back or advancement usually leaves soft tissue redundancy or deficiency along with its displacement. We have combined genioplasty with orthognathic surgery after intermaxillary fixation through a separate incision to get aesthetic improvement in the chin area in 28 patients. The authors obtained the aesthetic profile of the chin and lower lip according to various soft tissue analysis as follows: 1) The depth of the mentolabial fold 2) The distance from the E-line to labrale inferius (LI) 3) N-ANS/ANS-Me The soft tissue disproportion and residual deformities which were not usually corrected by the orthognathic surgery alone could be improved by combining it with genioplasty.
Chin ; Congenital Abnormalities ; Genioplasty* ; Humans ; Lip ; Maxilla ; Orthognathic Surgery

Facial asymmetry can be classified into the rolling-dominant type (R-type), translation-dominant type (T-type), yawing-dominant type (Y-type), and atypical type (A-type) based on the distorted skeletal components that cause canting, translation, and yawing of the maxilla and/or mandible. Each facial asymmetry type represents dentoalveolar compensations in three dimensions that correspond to the main skeletal discrepancies. To obtain sufficient surgical correction, it is necessary to analyze the main skeletal discrepancies contributing to the facial asymmetry and then the skeletal-dental relationships in the maxilla and mandible separately. Particularly in cases of facial asymmetry accompanied by mandibular yawing, it is not simple to establish pre-surgical goals of tooth movement since chin deviation and posterior gonial prominence can be either aggravated or compromised according to the direction of mandibular yawing. Thus, strategic dentoalveolar decompensations targeting the real basal skeletal discrepancies should be performed during presurgical orthodontic treatment to allow for sufficient skeletal correction with stability. In this report, we document targeted decompensation of two asymmetry patients focusing on more complicated yaw-dependent types than others: Y-type and A-type. This may suggest a clinical guideline on the targeted decompensation in patient with different types of facial asymmetries.
Chin ; Facial Asymmetry* ; Humans ; Mandible ; Maxilla ; Orthognathic Surgery ; Tooth Movement

The treatment plan for orthognathic surgery must be based on accurate predictions, and this can be produced the most esthetic results. Treatment of prognathic mandible in adult is usually orthognathic surgery using mandible set back, but mandible with retruded chin point os needed additional chin augmentation. In this case, the directions between mandible and chin point are different therefore, the prediction of soft tissue reactions must be modified. In this study, we materialize the patients who was taken orthognathic surgery due to prognathic mandible, 11each(Group A) was taken only Bilateral Sagittal Sprit Ramus Osteotomy (BSSRO), 9each(Group B) was taken additional advancement genioplasty. The lateral cephalometric radiography taken 8 months later after orthognathic surgery by this patients were used. The results of this study were as follows 1. The profile of lips was favorable after surgery due to upper lip to E-line became prominent and lower lip to E-line was retruded. 2. In both group, upper lip moved posteriorly and national angle was increased. 3. The ratio of the soft tissue profile change in POGs point to skeletal B point movement was 84% in group A and 66% in group B, and there was statistical significance between group A and group B. 4. Vertical movement of hard tissue points is decreased in group A.
Adult ; Chin ; Genioplasty ; Humans ; Lip ; Mandible* ; Orthognathic Surgery ; Osteotomy ; Radiography

This study was designed to test the possibility of using a standardized lateral facial photographs as a clinical tool which produce the prediction of postsurgical soft-tissue profile changes associated with surgical correction in skeletal CIII patients. The number of the patients involved in this study were 27 in total, including 11 male patients and 16 female patients. A practical method to the utilization of presurgical photo prediction for mandibular prognathic patients has been presented. To predict postoperative facial appearance, montage photographs were superimposed on standard facial reference photos taken preoperatively. Within the limitations of its technology, postoperative predictions generated by this method were of sufficient accuracy, especially mandible and chin area, for clinical use. In addition, they provide valuable communication and diagnostic information which may be used in formulating treatment plan in cases requiring corrective orthognathic surgery. But, the lip changes were somewhat exaggerated by photo prediction. Consequently, the photo prediction seems suitable for planning profile changes in orthognathic surgery that include mobilization of one main mandibular fragment. Futher investigations are needed to determine whether changes of soft-tissues and hard-tissues are sufficiently reproducible so that more meaningful predictive values can he established.
Chin ; Female ; Humans ; Lip ; Male ; Mandible* ; Orthognathic Surgery

BACKGROUND: The purpose of the present study was to investigate the differences in the position and shape of the anterior loop of the inferior alveolar nerve (ALIAN) in relation to the growth pattern of the mandibular functional subunit. METHODS: The study was conducted on 56 patients among those who had undergone orthognathic surgery at the Gangnam Severance Hospital between January 2010 and December 2015. Preoperative computerized tomography (CT) images were analyzed using the Simplant OMS software (ver.14.0 Materialise Medical, Leuven, Belgium). The anterior and inferior lengths of ALIAN (dAnt and dInf) and each length of the mandibular functional subunits were measured. The relationship between dAnt, dInf, and the growth pattern of the mandibular subunits was analyzed. RESULTS: The length of the anterior portion of ALIAN (dAnt) reached 3.34 ± 1.59 mm in prognathism and 1.00 ± 0.97 mm in retrognathism. The length of the inferior portion of ALIAN (dInf) reached 6.81 ± 1.33 mm in prognathism and 5.56 ± 1.34 mm in retrognathism. The analysis of Pearson’s correlation coefficiency on all samples showed that the lengths of functional subunits were positively correlated with the loop depth. The length of the symphysis area in prognathic patients was positively correlated with the anterior loop depth (p = 0.005). CONCLUSIONS: Both the anterior and inferior length of ALIAN are longer in prognathic patients. Especially, it seems to be associated with the growth of the symphysis area.
Chin ; Genioplasty ; Humans ; Mandibular Nerve ; Orthognathic Surgery ; Prognathism ; Retrognathia

Chin ; Humans ; Hyoid Bone ; Orthognathic Surgery ; X-Ray Film

surgery remains a problem during preoperative planning because of the difference relative movements of the hard and soft tissues. This study was performed to predict the changes of upper and lower lips after BSSRO with non-rigid fixation. MATERIAL AND METHODS: 15 patients with skeletal Class III malocclusion treated by bilateral sagittal split ramus osteotomy(BSSRO) and mandibular setback were selected for analysis. Cephalometric data of presurgery and postsurgery 12 months were used. Wilcoxon signed rank test, calculation of Spearmans correlation rho and simple regression analysis were performed to predict the relations between hard tissue changes and soft tissue changes. RESULTS: The horizontal change of hard tissue Pogonion and those of lower lips showed high correlation and the ratios were from 71% to 84%. The horizontal change of hard tissue Pogonion and those of chin showed high correlation and the ratios were from 90% to 92%. The horizontal change of hard tissue Pogonion and those of upper lips showed moderate correlation and the ratios were from 7% to 18%. CONCLUSION: This study suggests that the changes of lower lips are highly affected by the hard tissue change of mandible and those of upper lips are moderately affected. In comparison with other studies, no significant differences were found among the fixation methods.]]>
Chin ; Humans ; Lip ; Malocclusion ; Mandible ; Orthognathic Surgery ; Prognathism

OBJECTIVETo investigate a technique for correction of severe microgenia.

METHODSThe mandibular symphysis was exposed through intraoral mucous incision. Two parallel osteotomies were performed under mental foramen. The mobilized segments were advanced like two steps and fixed rigidly with miniplate.

RESULTSFrom June, 2004 to Dec, 2005, 10 cases with severe microgenia were treated with this technique. The duration of follow-up was six months. The mean chin advancement was 1.1 cm and the mean chin vertical increase was 0.7 cm. All the patients healed very well with satisfactory aesthetic result.

CONCLUSIONSWith this two-step genioplasty, the chin can be moved to ideal position with a natural appearance. It is a reliable method for severe microgenia.

Adult ; Chin ; abnormalities ; surgery ; Female ; Humans ; Mandible ; abnormalities ; surgery ; Osteotomy ; Young Adult