Mandibular Margin Research Articles

Clinical application of titanium plate reconstruction of mandibular defect: 10 years of follow up

To summarize the postoperative complications of reconstruction of mandible defect with titanium reconstruction plate. A total of 111 cases of the mandibular defect caused by various reasons and repaired by titanium reconstruction plate in the Department Oral and Maxillofacial Surgery of the affiliated Hospital of Qingdao University from 2003 to 2012 were collected and followed up. The complications were analyzed. Thirty-seven percent of 111 cases showed long term complications. The titanium fracture was the main complication(16%[18/111]), followed by stress-shielding (9%[10/111]), infection(8%[9/111]), and titanium plate exposure(4%[4/111]). Titanium plate fracture occurred within 8 months and 3 years after surgery. The simple titanium plate reconstruction had the highest rate of plate fracture(30%[15/50]). Stress-shielding in non-vascularized bone graft was more significant than that in vascularized bone graft(P<0.05). When replaced by mini-titanium plate, the stress-shielding effect disappeared gradually. When the retention of mandibular margin height was less than 1 cm with the use of reconstruction plate, the postoperative complications were prone to occur. Bone graft is the best way to reconstruct mandibular defect, and simple reconstruction plate repair is applied only as a transitional means for high degree of malignancy, obvious recurrence tendency tumor or special reasons such as age etc, which are not suitable for bone graft. The reconstruction plate fixation is not recommended for bone graft, especially non-vascularized bone graft. The retention of mandibular margin with reconstruction plate fixation is open to discussion.

Anthropometric Analysis of Facial Foramina in Korean Population: A Three-Dimensional Computed Tomographic Study.

BackgroundPosition of the facial foramina is important for regional block and for various maxillofacial surgical procedures. In this study, we report on anthropometry and morphology of these foramina using three-dimensional computed tomography (3D-CT) data.MethodsA retrospective review was performed for all patients who have undergone 3D-CT scan of the facial skeleton for reasons other than fracture or deformity of the facial skeleton. Anthropometry of the supraorbital, infraorbital, and mental foramina (SOF, IOF, MF) were described in relation to facial midline, inferior orbital margin, and inferior mandibular margin (FM, IOM, IMM). This data was analyzed according to sex and age. Additionally, infraorbital and mental foramen were classified into 5 positions based on the anatomic relationships to the nearest perpendicular dentition.ResultsThe review identified 137 patients meeting study criteria. Supraorbital foramina was more often in the shape of a foramen (62%) than that of a notch (38%). The supraorbital, infraorbital, and mental foramina were located 33.7 mm, 37.1 mm, and 33.7 mm away from the midline. The mean vertical distance between IOF and IOM was 13.4 mm. The mean distance between MF and IMM was 21.0 mm. The IOF and MF most commonly coincided with upper and lower second premolar dentition, respectively. Between the sex, the distance between MF and IMM was significantly higher for males than for female. In a correlation analysis, SOF-FM, IOF-FM and MF-FM values were significantly increased with age, but IOF-IOM values were significantly decreased with age.ConclusionIn the current study, we have reported anthropometric data concerning facial foramina in the Korean population, using a large-scale data analysis of three-dimensional computed tomography of facial skeletons. The correlations made respect to patient sex and age will provide help to operating surgeons when considering nerve blocks and periosteal dissections around the facial foramina.

Redescription of late-instar larva of Scydmoraphes sparshalli (Denny)Coleoptera: Staphylinidae, Scydmaeninae).

The larva of Scydmoraphes sparshalli is redescribed. This is the first complete description of an immature Scydmoraphes with special focus on the chaetotaxic characters. The larva is unique among Cyrtoscydmini in having three pairs of stemmata, a very long sensory appendage of the antennomere II, mandibles with mesal row of microserrations interrupted by smooth portion of mandibular margin; maxillary mala with asetose apex and a row of very long, modified setae on mesal margin, and extremely elongate maxillary palpomere III and labium. A comparative study of previous descriptions resulted in recognizing a misidentification of a Scydmoraphes larva (the "Typ 2-Larve" of Schmid) as a putative Neuraphes (Pararaphes). The serial homology of chaetotaxic structures in the larva of Scydmoraphes sparshalli is discussed, and comparative notes on the larvae of Scydmoraphes, Neuraphes and Stenichnus are given, with an identification key.

Effects of hyoid position on surgical treatment outcome for patients with obstructive sleep apnea hypopnea syndrome

To evaluate the predictive value of the position of the hyoid in surgical outcomes of velopharyngeal surgery for obstructive sleep apnea hypopnea syndrome (OSAHS). The polysomnography, CT, and anthropometry data were retrospectively reviewed from patients who underwent revised uvulopalatopharyngoplasty with uvula preservation (H-UPPP) simply or the combination of H-UPPP and transpalatal advance pharyngoplasty (TAP) for OSAHS from July 2008 to December 2011. OSAHS was diagnosed by polysomnography (PSG) in 128 patients who underwent H-UPPP or H-UPPP with TAP surgery for their sleep disorder. After surgical treatment, the patients were evaluated by PSG. The 128 patients included were all male, the mean age of these patients was (39.6±8.5) years, ranged from 19 to 66 years. Seventy-seven patients were successfully treated and 51 did not respond to surgical treatment. The overall apnea hypopnea index (AHI) improved from (58.2±22.4) times/h preoperatively to (20.6±18.1) times/h postoperatively (t=14.9, P<0.001). The vertical distance from inferior margin of hyoid to the inferior mandibular margin (D-HM) was the only parameter that had a significant difference between responders [(14.6±7.7)mm] and non-responders [(19.4±8.0)mm] (t=3.452, P=0.001). D-HM, AHI and the lowest blood oxygen saturation were significant predictors of surgical outcomes (P<0.05). There was a significant correlation between the D-HM and the postoperative AHI (r=0.284, P=0.001). The D-HM of ≥23 mm could predict the postoperative AHI of >10 times/h a specificity of 95.2%. The D-HM is a negative predictor of surgical outcomes, patients with a D-HM of ≥23 mm are inappropriate candidates for velopharyngeal surgery.

Delayed Methicillin-Resistant Staphylococcus aureus Infection on a Mandibular Angle Fracture with Absorbable Plates.

Delayed Methicillin-Resistant Staphylococcus aureus Infection on a Mandibular Angle Fracture with Absorbable Plates.

What is the difference between the inferior labial artery and the horizontal labiomental artery?

The inferior labial artery (ILA) and horizontal labiomental artery (HLA) can be regarded as the main arteries used in the lower lip pedicle for the perioral reconstruction. However, the courses of the ILA and HLA are described in diverse ways, and there is no obvious standard for distinguishing between them. The aim of this study was to elucidate the distribution patterns of the ILA and HLA, and the significance of the HLA in the vascularization of the lower lip. Sixty-three hemifaces from 18 Korean and 19 Thai cadavers were used in this study. The distribution patterns of the arteries of the lower lip area were classified based on the assumption that the HLA travels in the middle of the lower lip area, while the ILA runs along the lower lip border. The arterial distribution pattern of the HLA was classified into three types (I-III): type I, where the HLA ran horizontally in the lower lip area; type II, where the HLA curved upward to the vermilion border of the lower lip; and type III, where the HLA bifurcated into two branches. The ILA was also classified into three types (A-C): type A, where the ILA was not observed; type B, ILA was ramified from facial artery at the level of mouth corner; and type C, ILA arose from the superior labial artery (SLA) and supplied the lower lip vermillion border. Types I, II, and III were observed in 52.4 % (33/63), 39.7 % (25/63), and 7.9 % (5/63) of cases, respectively; and types A, B, and C were observed in 52.4 % (33/63), 36.5 % (23/63), and 11.1 % (7/63) of cases. Consideration of the two artery classifications together revealed seven types: type IA (14.3 %, 9/63), type IB (28.6 %, 18/63), type IC (9.5 %, 6/63), type IIA (30.2 %, 19/63), type IIB (7.9 %, 5/63), type IIC (1.6 %, 1/63), and type III (7.9 %, 5/63). The distance between the HLA and the midpoint between the mouth corner and the inferior mandibular margin was 0.4 ± 3.1 mm (mean ± SD) inferior to this point. The ILA and HLA should be differentiated according to the location of their origin rather than their terminating areas. The HLA could be considered as the main artery supplying the lower lip mucosa.

Anatomy-based image processing analysis of the running pattern of the perioral artery for minimally invasive surgery

We aimed to elucidate the tortuous course of the perioral artery with the aid of image processing, and to suggest accurate reference points for minimally invasive surgery. We used 59 hemifaces from 19 Korean and 20 Thai cadavers. A perioral line was defined to connect the point at which the facial artery emerged on the mandibular margin, and the ramification point of the lateral nasal artery and the inferior alar branch. The course of the perioral artery was reproduced as a graph based on the perioral line and analysed by adding the image of the artery using MATLAB. The course of the artery could be classified into 2 according to the course of the alar branch - oblique and vertical. Two distinct inflection points appeared in the course of the artery along the perioral line at the ramification points of the alar branch and the inferior labial artery, respectively, and the course of the artery across the face can be predicted based on the following references: the perioral line, the ramification point of the alar branch (5∼10 mm medial to the perioral line at the level of the lower third of the upper lip) and the inferior labial artery (5∼10 mm medial to the perioral line at the level of the middle of the lower lip).

Mandibular Marginal Contouring in Oriental Aesthetic Surgery

In aesthetic mandibular contouring surgery, which is often conducted in Asians, the operative procedure is thought to deliver a more aesthetic mandibular shape by means of contouring conducted as a whole from the ramus to the symphysis. The authors describe the refined concept and operative procedures of mandibular marginal contouring. For the 7-year period from 2004 to 2011, mandibular marginal contouring has been used in 57 consecutive series of Japanese subjects. Patient ages ranged from 18 to 33 years, and the subjects included 15 men and 42 women. The surgery was carried out by cutting off the protruding deformed mandibular margin from the ramus to the symphysis. In 53 of 57 cases, the focus was on angle contouring. Concomitant genioplasty by horizontal osteotomy of the chin was conducted in 42 of 57 cases (recession, advancement, shortening, elongation, and correction of the shift variously). In 22 materials exhibiting bulk around the mandibular, the ramus to the body was excised sagittally and thinned. In all the patients, mandibular marginal contouring from the ramus to the symphysis was completed. Partial masseter muscle resection was conducted in 11 of 57 cases. Mandibular contouring effectively achieved a highly satisfactory result in all cases. The upper portion of the peripheral branch of the trunk of the mental nerve was dissected by an electric scalpel in 1 case but sutured immediately using an 8-0 nylon stitch. Transient palsy of the mental nerve was noticed in a few cases but subsided in 1 to 2 months. No particular complications were encountered. No secondary revision was required in this series. In mandibular angle plasty, mandibular marginal contouring from the ramus to the symphysis should be carried out by cutting off the angle keeping in mind the entire mandibular shape. This concept and the procedure can deliver greater patient satisfaction.

Determination of lingual vascular canals in the interforaminal region before implant surgery to prevent life‐threatening bleeding complications

Profuse hemorrhage and airway obstruction may occur during or after the implant surgery in the interforaminal region. The prevention from this complication requires identifying the location of the mandibular lingual vascular canals (MLVCs). The purpose of this study was to evaluate the anatomical variations of MLVCs and to determine the safety margins for implant placement in interforaminal region. Computer tomography (CT) images of 200 consecutive patients were reexamined retrospectively by a radiologist and a maxillofacial surgeon to evaluate the presence of the MLVCs entering the mandible. The diameter and the number of the canals, the distance between the entrance of the canal and mandibular midline, and the height of the entrances of the canals from the inferior mandibular margin were measured. Two hundred and thirty-six median lingual canals (MLCs) and 159 lateral lingual canals (LLCs) were found in 200 patients. Significant differences were found between the number of lingual canals in the midline and canine regions (P < 0.001). There is a potential risk of complications due to the injuries of the vessels entering the lingual cortical bone through a number of bone canals during implant placement in the interforaminal region.

Cell adhesion molecule 1 is a new osteoblastic cell adhesion molecule and a diagnostic marker for osteosarcoma

AimsAn immunohistochemical screen for mouse embryos showed that cell adhesion molecule 1 (CADM1), which is an immunoglobulin superfamily member, was expressed in developing bones. Here, we determined the cell types expressing CADM1 and examined its usefulness in the differential diagnosis of osteosarcoma. Main methodsSerial sections of murine developing mandibles were stained with anti-CADM1 antibody, by a coloring substrate reactive to alkaline phosphatase (ALP), a broad osteoblastic marker for preosteoblasts to osteoblasts, and by in situ hybridization for osteopontin (OPN), a marker for mature osteoblasts. CADM1 immunohistochemistry was also performed on human remodeling bones, osteosarcomas and other soft tissue tumors. Key findingsCADM1 immunohistochemistry for the mandible revealed that morphologically identifiable osteoblasts expressed CADM1 on their plasma membranes, but neither osteocytes nor bone lining cells did. At the mandibular margin, not only OPN-positive cells but also OPN-negative, ALP-positive cells were CADM1-positive, whereas inside the mandible, OPN-positive cells were often CADM1-negative. Clear membranous staining was detected in the majority of osteosarcomas (46/57), whereas only 13% (6/46) of the other soft tissue tumors were CADM1-positive (P<0.001). SignificanceThese results indicated that CADM1 was a novel osteoblastic adhesion molecule that is expressed transiently during osteoblastic maturation, and a useful diagnostic marker for osteosarcoma cells.

A New Route for Passing a Free Flap Vascular Pedicle Using Contralateral Facial Vessels as Recipient Vessels in Skull Base Reconstruction

A New Route for Passing a Free Flap Vascular Pedicle Using Contralateral Facial Vessels as Recipient Vessels in Skull Base Reconstruction

Versatile Use of Submental Tissue for Reconstruction of Perioral Soft Tissue Defects

To obtain optimum aesthetic result, perioral soft tissue defects require reconstruction using similar tissue. The submental area has very similar characteristics to perioral soft tissue and consists of thin, pliable tissue with a perfect color match. Therefore, we have used submental tissues for reconstruction of perioral soft tissue defects and application of the techniques, and results are discussed in this article. Between February 2001 and April 2008, 14 perioral soft tissue reconstruction procedures using the submental tissues were performed. The defect was on the upper lip including nasal columella in 5 cases, mentum in 3 cases, and oral commissure including buccal cheek in 6 cases. The techniques that were used included composite graft in 3 cases, local advancement flap in 3 cases, pedicled flap in 5 cases, and free flap in 3 cases. Patients were followed up for 9 months to 5 years. During this period, no major complications were noted, and satisfactory aesthetic results were obtained. All transferred submental tissues survived. In all patients, donor defects were closed primarily except in cases of local advancement flap. The donor-site scar was inconspicuous and well hidden below the mandibular margin and did not restrict neck motion in all patients. In particular, hair restoration on the flap was excellent in male patients. We believe that the submental area can provide useful soft tissue for perioral soft tissue defects because it provides a good color and texture match with perioral skin and can be harvested with minimal donor-site morbidity.

Topography of the masseter muscle in relation to treatment with botulinum toxin type A

The objective of this study was to provide the safest and most efficient site for injection of botulinum toxin type A into the masseter muscle. This study was performed on 40 hemifaces from cadavers. The surface of the masseter was compartmentalized into areas I to VIII. Areas I, III, V, and VII were assigned to represent the upper 4 compartments from the posterior aspect of each muscle, and areas II, IV, VI, and VIII were assigned to represent the lower 4 compartments. The parotid gland usually covered compartments I and II, and the marginal mandibular branch of the facial nerve was located a mean of 7.4 mm above the inferior mandibular margin. The parotid duct was usually located above the reference line connecting the tragus and the cheilion. The center of compartment VI is the safest and most efficient injection site for botulinum toxin type A into the masseter muscle.

下顎前歯部歯槽骨切り術・オトガイ形成術施行後に癒合不全を呈した下顎前突症の１例

A 40-year-old female visited our department in June 2008 with chief complaints of intraoral denudation of the canine root, occlusion anomaly, and mastication disorder. She had a history of mandibular anterior subapical osteotomy and genioplasty by removal of the mandibular margin of the mental region under general anesthesia in another hospital in June 2007. In December 2007, an aperture was found at the osteotomy site and plate fixation was performed in the same hospital in January 2008. However, denudation of the canine root was found in February 2008 with a mastication disorder that had persisted since the initial surgery, which led her to visit to our department.At her initial visit, denudation of the canine root was confirmed. The right molars were missing and no contact was found in the anterior teeth. Skin mobility in the mental region was limited, indicating oral food intake without mastication. The patient was diagnosed as fissure fracture of the mandibular bone at the distal region of the lower left canine and faulty union of the alveolar osteotomy site.Alveolar osteotomy was repeated and the mandibular fracture was fixed under general anesthesia in September 2008. The cortical bone of the former alveolar osteotomy site showed faulty union. Following repeated osteotomy, the dentures were reconstructed by supporting them with preoperatively prepared plate splints and wire splints to check the occlusion, and then the osteotomy site was fixed with a miniplate. Iliac bone was grafted in the bone gap, and intermaxillary anchorage was retained for 20 days postoperatively. Following treatment, the occlusion in the anterior teeth improved and the patient was able to take regular food. However, continuous follow-up is necessary because of persistent partial denudation of the canine root and denudation of the grafted bone.In the diagnosis and treatment of jaw deformities to correct occlusion and masticatory functions, we consider that preoperative and postoperative occlusal management is important, especially when it appears to be difficult to obtain stability of postoperative occlusion.

Localization of important facial foramina encountered in maxillo‐facial surgery

Knowledge of the location of foramina in the maxillo-facial region is necessary in clinical situations requiring regional nerve blocks and in open as well as endoscopic surgical procedures to avoid injury to corresponding nerves. In this study, measurements were taken on 79 adult dried human skulls to determine the position of the supraorbital, infraorbital, and mental foramina. Supraorbital foramina were found to be approximately 25 mm lateral to the midline, 30 mm medial to the temporal crest of the frontal bone, and 2-3 mm superior to the supraorbital rim. Additional exits for branches of the supraorbital nerve were present in 14% of skulls. The intersection of the zygomatico-maxillary suture with the inferior orbital rim was a readily palpable landmark for locating the infraorbital foramen. This foramen was approximately 7 mm inferior to the inferior orbital rim and 28.5-mm lateral to the midline. Mental foramina were on average, 25.8-mm lateral to the midline and about 13-mm superior to the inferior mandibular margin. Both the infraorbital and mental foramina were most often on a vertical line with the second premolar (Position 3). The distances of the foramina from the midline were similar on both sides demonstrating facial symmetry. In about 80% of skulls, the supraorbital, infraorbital, and mental foramina/notches were along the same vertical line. These measurements may be of value to clinicians in localizing and safeguarding these nerves and providing effective nerve blocks.

A NEW SPECIES OF TREEFROG OF THE GENUS LITORIA (HYLIDAE) FROM THE LOUISIADE ISLANDS, PAPUA NEW GUINEA

I describe a new species of treefrog of the genus Litoria from Sudest Island, in the Louisiade Islands, off the southeastern tip of New Guinea. The new species is readily distinguishable from all other Papuan species of the genus except L. prora and L. humboldtorum in its possession of fully webbed hands and a fleshy rostral spike. It is distinguished from these species by its larger size, reduced crenelated fringes on arms and legs, absence of heel lappets, reduced papillae on the mandibular margin, and details of color pattern. I describe the tadpole for the new species and show that it differs from that of L. humboldtorum in morphology and color pattern. All three species form cohesive, distinct clusters in multivariate morphometric space. Morphologically, the new species most closely resembles L. humboldtorum, known from Yapen Island and the nearby New Guinea mainland 2000 km to the northwest. The new species was not found in recent surveys of nearby Rossel and Misima islands, the other large islands of the Louisiade group, and it may be restricted to Sudest Island.

Improvement of Functional and Aesthetic Results for Patients after Creation of Diversion Loop for Cervical Esophagus-Case Report

Choking is a serious problem in pharyngoesophageal reconstruction. These patients have to make a choice between preservation of vocal function but using permanent jejunostomy for feeding, and oral intake but using permanent tracheostomy for breathing. For patients who had chocking from previous injury to epiglottis, a new solution is creation of a diversion loop which allows food to pass from the oral vestibule to cervical esophagus. However, there is a disadvantage of the diversion loop. Because the jejunal flap was placed at subcutaneous layer, the patients may complain of the disfigurement due to the bulging of the chin. When the patients who received this procedure of diversionary loop had established good swallowing function, and they complained the disfigurement of the bulging of the chin, these patients are evaluated, including the mandible X-ray which is used to make sure the position of the tooth buds. A transverse skin incision is made for exploration of the mandibular tubercle, which is then trimmed off about 0.7~1 cm in height and 2 cm in width. The neck scar is also revised with multiple Z-plasties. Significant improvement in the function and aesthetic results was achieved. This is revealed on psychological interview. After removal of the mandibular margin some patients even got improvement in the speed of swallowing as revealed by dynamic esophagogram. The marginal mandibulectomy further contributed to the value of the diversion loop method, especially for young female patients.

Inferior Alveolar Nerve Canal Position: A Clinical and Radiographic Study

To document a clinically relevant position of the inferior alveolar nerve (IAN) in dentate patients and identify patient factors associated with IAN position. The investigators used a cross-sectional study design and a study sample of subjects who had a radiographically identifiable IAN canal and at least 1 mandibular first molar was enrolled. Predictor variables were age, gender, and race. Outcome variables were the linear distances between the buccal aspect of the IAN canal and the outer buccal cortical margin of the mandible, and the superior aspect of the IAN canal and the alveolar crest. Appropriate uni-, bi-, and multivariate statistics were computed. The study sample was composed of 50 patients with a mean age of 42 years, 42.0% were male, and 73.2% were white. On average, the buccal aspect of the canal was 4.9 mm from the buccal cortical margin of the mandible. The superior aspect of the IAN canal was 17.4 mm inferior from the alveolar crest. Age and race were statistically associated with IAN position relative to the buccal cortical mandibular margin (P<.05). None of the demographic variables were associated with vertical position. The IAN canal was 4.9 mm and 17.4 mm from the buccal and superior cortical surfaces of the mandible, respectively. The bucco-lingual IAN canal position was associated with age and race. Older patients and white patients, on average, have less distance between the buccal aspect of the canal and the buccal mandibular border. To minimize the risk of IAN injury, these variables should be considered when planning mandibular osteotomies or using monocortical plates.

Anesthesia in a child with fibrodysplasia ossificans progressiva

We describe the anesthesia management of a 12-year-old girl, diagnosed with fibrodysplasia ossificans progressiva (FOP), who presented with a submandibular abscess. FOP is a rare, inherited disorder with heterotopic bone formation and progressive musculoskeletal disability. This disability ultimately confines patients to a wheelchair. Minor trauma following dental treatment may lead to ankylosis of the jaw. Subsequent to this disability, which resulted in poor dental hygiene, our patient developed a dental abscess. This spread along the mandibular margin and under the tongue. She presented with an impending airway compromise in an already difficult situation. The options for airway management in a child with limited mouth opening are discussed.

Skeletal Effects in Class II Treatment with the Functional Mandibular Advancer (FMA)?

The aim of this clinical study was to reveal skeletal effects during the treatment of Class II malocclusions in adolescents and young adults using a protrusive-acting fixed, rigid functional orthodontic appliance, and to quantify them in comparison with an untreated control group. We aimed to determine whether, and if so, to what extent skeletal effects diminish with increasing age, and whether inter-individual differences can be observed. To correct their intermaxillary jaw relationship, the functional mandibular advancer (FMA) was inserted in 16 adolescents and young adults (eight males, eight females, aged from 12 years, 3 months to 18 years, 7 months) presenting with a skeletal Class II malocclusion. The course of treatment was documented cephalometrically. In all patients, the FMA treatment led to neutroclusion or overcorrected neutroclusion and a marked reduction in overjet. The occlusion's improvement in the sagittal dimension (overjet reduction by 4.43 +/- 2.10 mm, molar relationship improvement by 3.88 +/- 1.12 mm) was achieved by a combination of dental effects (distalization of upper teeth, mesialization of lower teeth) and skeletal effects (mandibular growth stimulation). Excepting the position and morphology of the maxillary base and the condyle's dorsal position in the fossa, all sagittal skeletal and dental changes induced by the FMA treatment were statistically significant. There was a mean increase of 1.71 +/- 1.11 mm in sagittal length of the mandible, in the sagittal-diagonal dimension of 1.42 +/- 1.51 mm and 1.53 +/- 2.15 mm, as well as a slight, significant increase in the gonial angle area. Whereas the condylar position remained stable, a forward positioning of the chin and thus significant increase in distance length was recorded from the posterior condylar margin to the anterior mandibular margin. Treatment with a fixed functional appliance in Class II patients effected significant changes in mandibular growth and correction of the distal intermaxillary relationship even after the pubertal growth spurt in adolescents and young adults. While the proportion of the orthopedically-induced skeletal share is subject to substantial inter-individual variability in adolescents, the overall conclusion can be drawn that skeletal effects (= stimulation of mandibular growth) in general clearly lessen with increasing patient age. In young adult patients, the correction of a distal intermaxillary jaw relationship is manifested primarily as a dento-alveolar compensation for the skeletal malocclusion.