In the orthodontics process, intervention and sliding of an orthodontic bracket during the orthodontic process can arise large response of the labio-cheek soft tissue. Soft tissue damage and ulcers frequently happen at the early stage of orthodontic treatment. In the field of orthodontic medicine, qualitative analysis is always carried out through statistics of clinical cases, while quantitative explanation of bio-mechanical mechanism is lacking. For this purpose, finite element analysis of a three-dimensional labio-cheek-bracket-tooth model is conducted to quantify the bracket-induced mechanical response of the labio-cheek soft tissue, which involves complex coupling of contact nonlinearity, material nonlinearity and geometric nonlinearity. Firstly, based on the biological composition characteristics of labio-cheek, a second-order Ogden model is optimally selected to describe the adipose-like material of the labio-cheek soft tissue. Secondly, according to the characteristics of oral activity, a two-stage simulation model of bracket intervention and orthogonal sliding is established, and the key contact parameters are optimally set. Finally, the two-level analysis method of overall model and submodel is used to achieve efficient solution of high-precision strains in submodels based on the displacement boundary obtained from the overall model calculation. Calculation results with four typical tooth morphologies during orthodontic treatment show that: ① the maximum strain of soft tissue is distributed along the sharp edges of the bracket, consistent with the clinically observed profile of soft tissue deformation; ② the maximum strain of soft tissue is reduced as the teeth align, consistent with the clinical manifestation of common damage and ulcers at the beginning of orthodontic treatment and reduced patient discomfort at the end of treatment. The method in this paper can provide reference for relevant quantitative analysis studies in the field of orthodontic medical treatment at home and abroad, and further benefit to the product development analysis of new orthodontic devices.
Humans ; Periodontal Ligament/physiology* ; Orthodontic Wires ; Cheek ; Ulcer ; Tooth ; Finite Element Analysis

cheek pressures and suprahyoid and buccinator muscle activities at various head rotations and tilts, as independent variables. The data were subjected to one-way analysis of variance and post-hoc (linear contrast) testing. Tongue elevation pressures differed significantly when the head was flexed or extended compared to the neutral position (P<0.01). Suprahyoid muscle activity varied significantly when the head was rotated left or right compared to neutral, or tilted with the tongue elevated (P<0.01). Cheek pressure varied significantly when the head was rotated left or right compared to neutral, or tilted (P<0.01). Both tongue and cheek pressures increased significantly when the head was extended or rotated contralaterally compared to the neutral position. Suprahyoid muscle activity increased when the head was flexed or extended, or contralaterally or ipsilaterally rotated compared to the neutral position. Therefore, we suggest that head rotation or tilting could be used to vary oral pressure and muscle activity.]]>
Adult ; Cheek ; Female ; Head ; Humans ; Male ; Muscles ; Tongue

Salivary gland tumors usually appear in solitary mass in single salivary gland. The coexistence of tumors with different histological types occurring within a unilateral parotid gland is an extremely rare event. We experienced a case which two different types of malignant tumors developed at different time points in same gland; metachronous tumors. The second tumor was excised widely and reconstruction was performed by free tissue transfer. Sensory and motor nerve to the left cheek appeared to be intact, and circulation was adequate. This rare case was presented in this article.
Adenocarcinoma ; Cheek ; Neoplasms, Second Primary ; Parotid Gland ; Salivary Glands

Merkel cell carcinoma (MCC) is a relatively rare and aggressive cutaneous neuroendocrine malignancy. It is characterized by high rates of recurrence and metastasis, both to regional lymph nodes and to distant locations. Its characteristic clinical manifestation is a single, painless, hard, erythematous nodule on a sun-exposed area, particularly in older men. Surgical management of both the primary site and the sentinel lymph node is the standard of care. In this article, we describe the diagnosis and treatment of a case of MCC in the left cheek.
Carcinoma, Merkel Cell ; Cheek ; Diagnosis ; Head ; Humans ; Lymph Nodes ; Male ; Merkel Cells ; Neck ; Neoplasm Metastasis ; Recurrence ; Skin Neoplasms ; Standard of Care

Schwannoma is a slow-growing, well-demarcated, benign soft tissue tumor of the peripheral nerve sheath. It commonly develops in the head and neck region, usually in the parapharyngeal space. In this case, a 42-year-old woman visited the outpatient department to manage a painless mass on her left cheek. She had no history of concern and no neurological symptoms were observed. In the enhanced computed tomography scan, a 2.8 × 2.8 × 1.8 cm, heterogeneously enhanced tumor was detected in the left masseter muscle. A tumor resection under general anesthesia was planned. For the resection, a facelift incision was chosen; branches of the facial nerve were identified and retrogradely dissected. A well-marginated, yellowish, solid mass was found in the left masseter muscle. The mass was excised and given a histopathological diagnosis of schwannoma. A definite diagnosis of schwannoma, originating in the masseter muscle, is difficult to arrive at with radiographic findings alone; it is often misdiagnosed as intramuscular hemangioma. Histopathological examinations, including fine-needle aspiration or histological biopsy after surgery, are necessary. Using a facelift incision with retrograde facial nerve dissection, tumor resection in an intramasseteric lesion can be performed efficiently, without nerve damage, or leaving conspicuous scars on the face.
Adult ; Anesthesia, General ; Biopsy ; Biopsy, Fine-Needle ; Cheek ; Cicatrix ; Diagnosis ; Facial Nerve ; Female ; Head ; Hemangioma ; Humans ; Masseter Muscle ; Neck ; Neurilemmoma ; Outpatients ; Peripheral Nerves ; Rhytidoplasty

Lipoma is one of the most common benign tumors in the human body. However, they are uncommon in the oral cavity. Oral lipomas can occur on the cheeks, tongue, lips, gums and rarely on the floor of the mouth. Clinical symptoms are usually asymptomatic yellow masses. Sometimes the tumor grows and can have difficulty speaking and mastication. The treatment of lipoma is surgical excision, and recurrence is rare. We present a case of oral lipoma in an unusal location on the floor of mouth which is rare in the literature.
Cheek ; Gingiva ; Human Body ; Lip ; Lipoma ; Mastication ; Mouth Floor ; Mouth ; Recurrence ; Tongue

Cheilitis granulomatosa (CG) is a subset of orofacial granulomatosis (OFG) and considered to be a monosymptomatic form of Melkersson-Rosenthal syndrome (MRS), which is characterized by the triad of chronic lip swelling, facial paralysis, and fissured tongue. The labial swelling is thought to be associated with an orofacial swelling, which affects the chin, cheeks, and oral mucosa. Histologically, it is distinguished by noncaseating granulomas consisting of lymphohistiocytes and giant cells. Although systemic steroids with or without intralesional triamcinolone injections are the mainstay of treatment, and various agents have been proposed for this rare disease, no successful treatment modality has been reported in the literature yet. Herein, we present our experience with three different CG cases, which showed a varied level of positive response to the combination therapy.
Cheek ; Cheilitis ; Chin ; Facial Paralysis ; Giant Cells ; Granuloma ; Granulomatosis, Orofacial ; Lip ; Melkersson-Rosenthal Syndrome ; Mouth Mucosa ; Rare Diseases ; Steroids ; Tongue, Fissured ; Triamcinolone

Basal cell carcinoma (BCC) is the most common malignant skin tumor that usually develops in the head and neck region. It has a wide range of histological variants and constitutes approximately 65% of epithelial tumors. Cutaneous plasma cell infiltration can occur in individuals with various disorders, including amyloidosis, plasma cell neoplasm, and infectious diseases such as syphilis and deep fungal infections. A 53-year-old woman presented with scaly erythematous plaque on the left cheek. Skin biopsy showed smooth-bordered collections of basaloid proliferation with epidermal connection, and fibrotic stromas were noted in the dermis. Notably, mixed inflammatory cells were noted in the upper dermis, and they were mainly plasma cells. There was no evidence of other organ involvement and infection. She was diagnosed with BCC with plasma cell infiltration and was treated with topical and oral steroid, and excision was performed. In our literature review, plasma cell infiltration is related to tumor ulceration and more likely to be seen in patients with high-risk BCCs. Herein, we report a peculiar case of BCC with plasma cell infiltration.
Amyloidosis ; Biopsy ; Carcinoma, Basal Cell ; Cheek ; Communicable Diseases ; Dermis ; Female ; Head ; Humans ; Middle Aged ; Neck ; Neoplasms, Plasma Cell ; Plasma Cells ; Plasma ; Skin ; Syphilis ; Ulcer

Cactus spines can easily puncture the skin with only minor pressure. Removal of the offending cactus spine is the treatment of choice; however, it is very difficult, even with tweezers. A 17-year-old Korean girl presented for evaluation of multiple purple-colored macules and papules on the left cheek and left thumb. Two months earlier, she had pricked her finger and face on cactus spines while volunteering in Haiti. An ultrasound identified wedge-shaped echogenic materials suspected as cactus spines. We recommended surgical removal of the spines, but she vehemently refused. We then advised her to take amoxicillin/clavulanic acid and undergo regular follow-up. During the follow-up period, the spines dislodged spontaneously for easy removal and the patient removed them with tweezers. The lesions actually improved over the next several months. Here, we report this rare and interesting case for educational purposes because such a case has never been previously reported in Korea.
Adolescent ; Cactaceae ; Cheek ; Female ; Fingers ; Follow-Up Studies ; Haiti ; Humans ; Korea ; Punctures ; Skin ; Spine ; Thumb ; Ultrasonography ; Wounds and Injuries

Odontoma is an asymptomatic slow-growing odontogenic tumor. It is usually found by chance in the maxilla or mandible on radiography, or when it deforms the adjacent teeth. It is commonly found in patients who are 30 years of age or younger. We report our encounter with an odontoma within a dentigerous cyst found incidentally in a 56-year-old man. He presented with abnormal fullness in the right infraorbital area of the cheek. During the evaluation of the mass, we incidentally detected the odontogenic tumor within a dentigerous cyst in the patient's maxilla. Under general anesthesia, complete surgical drainage of the infraorbital cystic mass was performed. Enucleation of the odontogenic tumor and a bone grafting from the iliac bone were also performed. The final diagnosis was odontoma. After 2 years of follow-up, there was no sign of recurrence of the tumor. In case of odontogenic tumors, even in old patients, it is important to suspect an odontoma. When odontoma accompanies a dentigerous cyst, surgical excisional biopsy should be performed to rule out malignancy. In case of a large bony defect after enucleation, autogenous bone grafting is essential for reconstruction.
Alveolar Bone Grafting ; Anesthesia, General ; Biopsy ; Bone Transplantation ; Cheek ; Dentigerous Cyst ; Diagnosis ; Drainage ; Follow-Up Studies ; Humans ; Mandible ; Maxilla ; Middle Aged ; Odontogenic Tumors ; Odontoma ; Radiography ; Recurrence ; Tooth