Network analysis of three-dimensional hard-soft tissue relationships in the lower 1/3 of the face: skeletal Class I-normodivergent malocclusion versus Class II-hyperdivergent malocclusion.

BACKGROUND: The determining effect of facial hard tissues on soft tissue morphology in orthodontic patients has yet to be explained. The aim of this study was to clarify the hard-soft tissue relationships of the lower 1/3 of the face in skeletal Class II-hyperdivergent patients compared with those in Class I-normodivergent patients using network analysis. METHODS: Fifty-two adult patients (42 females, 10 males; age, 26.58 ± 5.80 years) were divided into two groups: Group 1, 25 subjects, skeletal Class I normodivergent pattern with straight profile; Group 2, 27 subjects, skeletal Class II hyperdivergent pattern with convex profile. Pretreatment cone-beam computed tomography and three-dimensional facial scans were taken and superimposed, on which landmarks were identified manually, and their coordinate values were used for network analysis. RESULTS: (1) In sagittal direction, Group 2 correlations were generally weaker than Group 1. In both the vertical and sagittal directions of Group 1, the most influential hard tissue landmarks to soft tissues were located between the level of cemento-enamel junction of upper teeth and root apex of lower teeth. In Group 2, the hard tissue landmarks with the greatest influence in vertical direction were distributed more forward and downward than in Group 1. (2) In Group 1, all the correlations for vertical-hard tissue to sagittal-soft tissue position and sagittal-hard tissue to vertical-soft tissue position were positive. However, Group 2 correlations between vertical-hard tissue and sagittal-soft tissue positions were mostly negative. Between sagittal-hard tissue and vertical-soft tissue positions, Group 2 correlations were negative for mandible, and were positive for maxilla and teeth. CONCLUSION: Compared with Class I normodivergent patients with straight profile, Class II hyperdivergent patients with convex profile had more variations in soft tissue morphology in sagittal direction. In vertical direction, the most relevant hard tissue landmarks on which soft tissue predictions should be based were distributed more forward and downward in Class II hyperdivergent patients with convex profile. Class II hyperdivergent pattern with convex profile was an imbalanced phenotype concerning sagittal and vertical positions of maxillofacial hard and soft tissues.

Facial soft-tissue shape changes after fixed edgewise treatment with premolar extraction in individual artificial-intelligence-classified facial profile patterns.

OBJECTIVE: To examine the patterns of pretreatment facial soft tissue shape in orthodontic cases with premolar extraction using artificial intelligence (AI) and to investigate the corresponding changes. METHODS: One hundred and fifty-two patients who underwent orthodontic treatment with premolar extraction were enrolled. Lateral cephalograms were obtained before and after the treatment. For each record, the outlines of the nose-lip-chin profile and corresponding 21 cephalometric variables were extracted. The AI method classified pretreatment records into three subject groups based on the feature variables extracted from the outline. Dentoskeletal and soft tissue facial form changes observed after treatment were compared statistically (P < 0.05) between the groups using ANOVA. Multivariate regression models were used for each group. RESULTS: Group 1 (n = 59) was characterized by Class II high-angle retrognathic mandible with an incompetent lip, group 2 (n = 55) by Class I malocclusion with retruded and thin lips, and group 3 (n = 38) by Class I malocclusion with an everted superior lip before treatment. The ratios of anteroposterior soft tissue to hard tissue movements in Group 1 were 56% (r = 0.64) and 83% (r = 0.75) for the superior and inferior lips, respectively, whereas those in Group 2 were 49% (r = 0.78) and 91% (r = 0.80), and 40% (r = 0.54) and 79% (r = 0.70), respectively, in Group 3. CONCLUSIONS: The modes of facial form changes differed depending on the pre-treatment profile patterns classified by the AI. This indicates that the determination of the pre-treatment profile pattern can help in the selection of soft tissue to hard tissue movement ratios, which helps estimate the post-treatment facial profile with a moderate to high correlation.

[Vascular occlusion following profile harmonization of the chin with hyaluronic acid fillers]. / Vasculaire occlusie na profielharmonisatie van de kin met hyaluronzuur fillers.

The use of dermal fillers for cosmetic procedures has increased rapidly both worldwide and in the Netherlands in recent years, which has led to an absolute increase in reported side effects and complications. Although most of these complications are mild, serious complications such as vascular occlusion can also occur. In this article, we describe a case of a 35-year-old woman who showed signs of reduced tissue perfusion and the early stage of skin necrosis following injection of hyaluronic acid fillers in the chin. This complication was successfully treated by ultrasound-guided injection of hyaluronidase, resulting in a full recovery without residual symptoms. To minimize the risk of serious complications treatment with hyaluronic acid fillers should be carried out by an experienced practitioner.

Soft Tissue Chondroma of the Chin.

Soft tissue chondromas are benign tumors, generally of the hands or feet, very rarely of the head and neck region. Repeated microtrauma may be as an initiating factor. The authors describe a case of a soft tissue chondroma of the chin in a 58-year-old male who had used a continuous positive airway pressure face mask for obstructive sleep apnea for 3 years. The patient presented with a hard mass on his chin for 1 year. Computed tomography imaging showed a heterogeneous enhancing mass, with calcification in the subcutaneous layer. Intraoperatively, the mass was beneath the mentalis muscle and abutted the mental nerve, without bone involvement. The diagnosis was a soft tissue chondroma. The patient recovered fully, without recurrence. The primary cause of soft tissue chondromas is unknown. The authors consider that continuous use of a continuous positive airway pressure face mask may play a role in the etiology.

Numb chin syndrome: What all oral health care professionals should know.

BACKGROUND: Numb chin syndrome (NCS) is a rare sensory neuropathy involving the mental nerve. Symptoms of NCS are often overlooked because of their apparent innocent nature; however, owing to the frequent association of NCS with malignancies, the opposite should be the rule. Oral health care professionals may be the first to encounter patients with NCS and should be aware of its clinical characteristics in an effort to decrease patient morbidity and mortality. TYPES OF STUDIES REVIEWED: A search in PubMed (MEDLINE) and the Cochrane Library was performed using the terms numb chin syndrome, numb chin, mental neuropathy, mental nerve neuropathy, and malignant mental nerve neuropathy, yielding 2,374 studies. After inclusion and exclusion criteria were applied, 102 studies remained. Descriptive statistics were performed, analyzing the etiology responsible for NCS, characteristics of NCS including associated symptoms, unilateral or bilateral nature, and information on professionals visited and examinations requested to make a diagnosis. RESULTS: NCS was associated with malignancy in 29% through 53% of the published cases. Twenty-eight percent of patients initially consulted an oral health care professional with the symptom of a numb chin. Patients more likely to have NCS were those from the ages of 61 through 70 years; 74% were unilateral; and the most common symptoms reported were numbness (100%), paresthesia (18%), and pain (17%). Forty-seven percent of the NCS cases were associated with a recurrent malignancy, and the most prevalent associated diagnoses were breast cancer (32%) and lymphoma and leukemia (24%). CONCLUSIONS: Oral health care professionals should be aware of the characteristics of NCS as they may be the first health care providers consulted for these symptoms. PRACTICAL IMPLICATIONS: A thorough medical and dental history as well as a complete cranial nerve screening should be performed on all patients, especially those with numbness, as this may prevent misdiagnosis and allow a timely referral and a substantial improvement of treatment course and prognosis.

The Effect of Weight-Loss Interventions on Cervical and Chin Subcutaneous Fat Depots; the CENTRAL Randomized Controlled Trial.

Accumulation of cervical and chin subcutaneous adipose tissues (SAT) represent known phenotypes of obesity. We aimed to evaluate the sensitivity of these fat storages to long-term weight-loss directed lifestyle-intervention and to assess their relations to bodily-adiposity, insulin-resistance, and cardiometabolic risk; We randomly assigned 278 participants with abdominal-obesity/dyslipidemia to low-fat or Mediterranean/low-carbohydrate diets +/- physical-activity. All participants underwent an 18 month whole-body magnetic resonance imaging follow-up, from which we assessed cervical and chin SAT-areas; Participants (age = 48 years; 90% men; body-mass-index = 30.9 kg/m2) had an 18-month adherence-rate of 86%. Cervical-SAT and chin-SAT decreased after 6-months (-13.1% and -5.3%, respectively, p < 0.001). After 18-months only cervical-SAT remained decreased compared to baseline (-5%, p < 0.001). Cervical and chin-SAT 18-month changes were associated with changes in weight (r = 0.70, r = 0.66 respectively; <0.001 for both) and visceral-adipose-tissue (VAT; r = 0.35, r = 0.42 respectively; <0.001 for both). After adjustment to VAT, waist-circumference, or weight-changes, chin-SAT 18-month reduction was associated with favorable changes in fasting-glucose (ß = 0.10; p = 0.05), HbA1c (ß = 0.12; p = 0.03), and homeostasis-model-assessment-of-insulin-resistance (ß = 0.12; p = 0.03). Cervical-SAT 18-month reduction was associated with decreased triglycerides (ß = 0.16; p = 0.02) and leptin (ß = 0.19; p = 0.01) independent of VAT; Cervical and chin-SATs are dynamic fat depots that correspond with weight-loss and are associated with changes in cardiometabolic profile. In long-term, chin-SAT displays a larger rebound compared with cervical-SAT. Chin-SAT accumulation is associated with in insulin-resistance, independent of central obesity. (ClinicalTrials identifier NCT01530724).

Numb chin syndrome secondary to infiltration of inferior alveolar nerve as a presentation of relapse in treated testicular lymphoma-diagnosis on PET/CT and MR neurography.

Numb chin syndrome (NCS) is a rare presentation of primary or recurrent malignant neoplasms among other non-neoplastic causes. The syndrome is characterized by altered sensations in the distribution of the mental nerve and presents with pain and paresthesias along the distribution of the inferior alveolar nerve and its branches. The primary diagnosis is indicated while following up patients through positron emission tomography/computed tomography (PET/CT) when a hypermetabolic focus is seen in the vicinity of the angle of the mandible. Further anatomical localization is performed using magnetic resonance (MR) neurography and postcontrast MR imaging, which demonstrates neural involvement. We hereby describe a case of a 56-year-old man, a treated case of DLBCL (diffuse large B-cell lymphoma), presenting with NCS and diagnosed with perineural invasion through PET/CT and further MR evaluation. To our knowledge, there are no other reports in the literature describing the MR neurography appearance of the inferior alveolar nerve in NCS. We hereby stress on the use of MR neurography followed by postcontrast 3D sequences with multiplanar reformatting for adequate lesion detection.

Plaque-Type Variant of Acquired Rhabdomyomatous Mesenchymal Hamartoma on the Chin: A Case Series.

ABSTRACT: Rhabdomyomatous mesenchymal hamartoma (RMH) is a rare benign tumor composed of skeletal muscle fibers and other mesenchymal-derived cells. The lesions are generally solitary sessile papules or skin tag lesions that occur during childhood. We retrospectively reviewed patients diagnosed with RMH pathologically between January 2001 and June 2020 at a tertiary medical center. A literature review was conducted. Seven plaque-type RMHs on the chin were found, including 6 in adults and one in a 14-year-old boy. The average age was 45.7 years. The onset of the RMH appearance was between several months and years. Pathologically, all patients showed a scattered haphazard arrangement of skeletal muscle bundles in the dermis and/or subcutis. Subcutis replaced by fibrous tissue and skeletal muscle bundles was present in 2 cases. Some skeletal muscles had a periadnexal distribution. This case series demonstrated a distinct clinical presentation of acquired RMH specifically located on the chin.

Sweet syndrome with perifollicular involvement because of koebnerization from facial hair plucking.

Sweet syndrome (SS), also known as acute febrile neutrophilic dermatosis, is an uncommon skin eruption characterized by fever, leukocytosis, and tender erythematous papules, nodules, and plaques. Histopathologically, SS lesions are characterized by marked superficial papillary edema with a dense neutrophilic infiltrate. SS is known to demonstrate both the Koebner phenomenon and pathergy. The majority of reported cases of these phenomena occur following significant cutaneous injury (e.g., biopsies, burns) rather than minor trauma such as pressure and friction. Here, we present the first known reported case of SS koebnerization secondary to minor grooming-related hair plucking. In addition, this is also the first reported case to our knowledge of SS with perifollicular involvement on histopathology.

The goniomaxillar length/goniomandibular length ratio in normal newborn infants: A clinical tool for defining chin position abnormalities.

Retrognathia (recessed chin) and prognathism (prominent chin) often present as signs of an underlying condition. Accurate clinical definitions are important. Yet their definitions were according to "clinical impression", or to seldom used X-ray criteria. We propose a statistical and anthropometric definition of retrognathia and prognathism based upon the ratio between the goniomaxillar length (distance between the gonion at the mandible angle and the subnasale and the goniomandibular length (distance between the mandible angle and the most anterior point of the bony chin). We assumed that an increase in the ratio indicates retrognathia and a decrease reflects prognathism. We conducted a prospective, observational, anthropometric study in 204 consecutive healthy term infants. Measurements took place on the second day of life, using sliding calipers. Mean ± SD of goniomandibular length (5.1 ± 0.3 cm), goniomaxillar length (5.4 ± 0.3 cm), were calculated. All measurements correlated significantly with gestational age, and with infant birthweight. The mean ± SD goniomaxillar length/goniomandibular length ratio was 1.06 ± 0.05. We defined a normal ratio as being within 2 SD of the mean, that is, between 0.96 and and 1.16. This ratio correlated with neither gestational age nor with birthweight. We conclude that the goniomaxillar length/goniomandibular length ratio can be calculated whenever retro - or prognathism is suspected. A ratio outside of the 95% confidence interval should help in making this diagnosis. An increase in this ratio beyond 2 SD above the mean (1.16) could be interpreted as retrognathia and a decrease beyond 2 SD below the mean (0.96) as prognathism.

Severe phymatous rosacea of the nose, cheeks, and chin treated with hydrosurgery.

Phymatous rosacea is a rare and severe form of rosacea that manifests as disfiguring soft-tissue hypertrophy and sebaceous gland hyperplasia and fibrosis. Most cases are surgically treated; surgical modalities vary, however, ranging from cryosurgery to conventional excision, and consensus guidelines for surgical management do not exist. The Versajet II Hydrosurgery System (Smith-Nephew) is a high-pressure, pulsatile lavage system. We present the case of a 75-year-old man with severe phymatous rosacea of the nose, cheeks, and chin who was successfully treated with the Versajet II Hydrosurgery System, yielding excellent contouring.

Comparison of three-dimensional soft-tissue evaluations between skeletal and pseudo-class III malocclusions.

The aim of our study was to compare soft tissue measurements with 3D imaging methods in individuals with untreated skeletal and pseudo-Class III malocclusions. The study sample consisted of 75 patients (38 males, 37 females, mean age 12.41 ± 2.35 years) with pseudo- and true skeletal Class III malocclusions and skeletal Class I malocclusions. Soft tissue evaluations of all patients were performed using 3D stereophotogrammetric facial images. In our study, 26 landmarks, 17 linear measurements, 13 angular measurements, and 5 volume measurements were made using the 3dMD Vultus software. The significance was determined to be p < 0.05 in ANOVA, Tukey tests. No significant differences were found among the groups in terms of demographic data (p > 0.05). The skeletal Class I control group had a significantly more extended upper lip and vermillion length as compared to the Class III groups. The soft tissue convexity angle and upper nasal angle were found to be wider in the Class III malocclusion group compared to those in the Class I control group. While the pseudo-Class III group had a significantly lower midface volume, chin volume was significantly higher in the skeletal class group. Upper lip volume was significantly higher in the Class I group. Using 3dMD for guiding clinicians in the differential soft and hard tissue diagnosis of pseudo-Class III malocclusions, differences were revealed in Class I patients in the middle part of the face. In the differential diagnosis of true Class III malocclusions, chin volume was found to be different from that of Class I patients.

Perceptions of chin asymmetries among dental professionals and laypersons.

INTRODUCTION: Previous studies have looked at a variety of dental and facial asymmetries and compared their detection by dental professionals with those of laypersons. However, few studies have analyzed the diagnosis and perception of chin asymmetries. In this study, we assessed whether dental professionals can recognize and diagnose facial asymmetries of the chin better than laypeople. METHODS: Chin asymmetries were analyzed through a series of edited frontal photographs of 2 subjects (male and female). The transverse position of the chin was digitally altered from 0° (no alteration) to 6° (most severe alteration). Participant responses were collected from laypersons (n = 64), nonorthodontist dentists (n = 58), and orthodontists (n = 145). Participants graded the photographs according to esthetic appeal using a visual analog scale. Statistical analysis produced diagnostic threshold levels for identifying chin asymmetries. RESULTS: Nonorthodontist dentists and orthodontists were better able to diagnose transverse chin asymmetry in the female subject at a lower threshold level of 2° of deviation, compared with laypersons at a 3° deviation. Orthodontists could diagnose transverse chin asymmetry in the male subject at a lower threshold level of 1° of deviation, compared with laypersons and nonorthodontist dentists at a 2° deviation. All 3 groups of raters graded very small or no chin asymmetries (1° and 0°) as more attractive, whereas high degrees of chin asymmetries (5° and 6°) were graded as most unattractive by all 3 groups. CONCLUSIONS: Transverse asymmetries of the chin influence the perception of facial attractiveness by laypersons, nonorthodontist dentists, and orthodontists. Subjects with small asymmetries are graded as most attractive, and subjects with large asymmetries are graded as least attractive. Orthodontists were the harshest graders, followed by the nonorthodontist dentists, whereas laypersons were the most lenient. The accuracy of diagnosing chin asymmetries varied among laypersons, nonorthodontist dentists, and orthodontists. Laypersons were the least accurate in diagnosing transverse chin asymmetries in a female subject, and they were just as accurate as nonorthodontist dentists when diagnosing this asymmetry in a male subject. Nonorthodontist dentists were just as accurate as orthodontists when diagnosing transverse chin asymmetries in a female subject, and orthodontists were the most accurate in diagnosing transverse chin asymmetries in a male subject.

[Complications due to an oral injury caused by diving]. / Complicaties na onbehandeld mondletsel bij duiken.

A 42-year-old man presented himself with a complaint of recurrent swelling of the chin. After clinical and radiographic examination, it was shown to be an injury caused by the use of an insufficiently disinfected mouthpiece when diving at an exotic destination. Oral injuries caused by diving mouthpieces are widely known. It is less well known that an untreated injury can ultimately lead to tooth loss.

Sialoblastoma in chin and management of treatment.

OBJECTIVE: Sialoblastoma is a rare salivary gland tumor mainly located in parotid. In this article, we aimed to review the clinical manifestations and treatments of sialoblastoma, especially to provide effective chemotherapy regimens to instruct internal medicine therapy for unresectable or recurrent tumors. METHOD: We reported a 1-year old girl who presented a left-sided firm facial mass and subsequently diagnosed as sialoblastoma. Afterwards, we reviewed and analyzed relevant literatures. RESULTS: Sixty-four cases of pediatric sialoblastoma were reviewed. Of them, surgical excision was the basic treatment, 17 cases received chemotherapy, and 15 cases got good response. Lung metastasis was reported in six patients, all of whom had good response to chemotherapy. CONCLUSION: Chemotherapy may play an important role in residual, extensive, metastatic and relapsed cases. In addition, lung metastasis was unlikely to exert a significant effect on prognosis.

Soft tissue changes: a comparison between changes caused by the construction bite and by successful treatment with a modified Twin-block appliance.

Background/objectives: Functional appliances are commonly used to correct Class II malocclusion. This study aimed to compare the facial soft tissue changes in Caucasians between pre-treatment and with the construction bite versus pre-treatment and completion of treatment with a modified Twin-block appliance (MTBA). Materials and methods: Fifty-eight Caucasian subjects with Class II division 1 malocclusion had 3D stereophotogrammetric images captured pre-treatment (T1), with the construction bite (T2), and on completion of MTBA treatment (T3). Twenty-six landmarks were located on each image and 10% were re-landmarked 1 month later. Soft-tissue linear and volumetric changes (T1-T2 and T1-T3) were analyzed using linear mixed effect models (SAS® Version 9.4, www.sas.com). Results: Forty-seven subjects [mean age 13.2 (SD 1.7) years] completed treatment [mean duration 9.8 (SD 3.8) months]. Differences between the changes from T1 to T2 versus T1 to T3 for upper facial and upper lip landmarks were insignificant (all P > 0.05) except for nasion, orbitale right, pronasale, and subnasale. For the same comparisons, lower lip and chin landmarks changed significantly (all P < 0.05) as did facial soft tissue volume (P< 0.0001). Limitations: There was no control group. Conclusion: The facial soft tissue changes from pre-treatment to with the construction bite were considerably more than those from pre-treatment to completion of treatment with a MTBA. Implication: With MTBA treatment, the soft tissue changes from pre-treatment to with the construction bite in situ, overestimate those from pre- to post-treatment.

Burkitt non-Hodgkin lymphoma presenting with mental neuropathy ('numb chin' syndrome) in an HIV-positive patient.

Mental nerve neuropathy is usually due to local trauma or dental causes, but may be a manifestation of malignancy. A patient with virologically controlled human immunodeficiency virus (HIV) infection presented with a 'numb chin' on the background of long-standing night sweats, malaise and weight loss, worsening respiratory symptoms, and lymphadenopathy. Burkitt non-Hodgkin lymphoma was diagnosed from histology of a lymph node. Imaging (magnetic resonance imaging and 18fluorodeoxyglucose [FDG]-positron emission tomography-computed tomography [PET-CT]) showed abnormal intracranial enhancement of the right mandibular nerve and extensive 18FDG-avid lymphadenopathy above and below the diaphragm, focal lesions in the spleen and within the right mandible. The patient received chemotherapy and remains in clinical and radiological remission seven years later. This case highlights the need for clinicians to maintain a high index of suspicion for underlying malignancy when an HIV-infected patient presents with new onset of a 'numb chin'. Additionally, it demonstrates the importance of functional 18FDG-PET-CT and neuroimaging in order to identify site(s) of pathology.