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71.
Authors – Wadhawan N, Kumar S, Kharbanda OP, Duggal R, Sharma R Aim – To document the alterations within the condyle‐glenoid fossa (C‐GF) complex and the positional changes of the glenoid fossa in the cranium after removable functional appliance therapy and after the completion of fixed appliance therapy. Setting and Sample – The Department of Orthodontics, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India. The study sample consisted of 12 growing children (eight girls and four boys) between 10 and 14 years of age with skeletal Class II division 1 malocclusion selected on well defined criteria. Materials and Methods – All patients were treated with either the Twin Block or the Bionator appliance followed by fixed appliances. Mean total treatment duration was 28 months. The changes in and around the C‐GF complex were evaluated using MRI at pre‐treatment stage, after functional appliance therapy and at the completion of fixed mechanotherapy. Results – Forward condylar position within the glenoid fossa and articular disc retrusion with respect to the condylar head were statistically significant after functional appliance therapy. However, the condyles had a relatively concentric position within the glenoid fossa, while the articular disc resumed its pre‐treatment position at the end of the treatment. Linear measurements from the centre of the external auditory meatus to the post‐glenoid spine revealed a 1.3‐mm forward relocation of the post‐glenoid spine along the Frankfurt Horizontal plane. Conclusions – Forward relocation of the C‐GF complex seems to be one of the mechanisms of action of functional appliances, while the internal anatomic arrangement within the temporomandibular joint (TMJ) complex normalizes to its pre‐treatment position.  相似文献   
72.
The present SEM study revealed the effect of 50 percent citric acid on the primary tooth enamel subsequent to mechanical pretreatment. The enamel of primary teeth was conditioned with 50% citric acid for 1, 1.5, 2, 3 and 5 minutes. A uniformly etched enamel surface was obtained at 5 minutes.  相似文献   
73.
Secondary bone grafting in cleft lip and palate patients is performed preferably before the eruption of permanent canine in order to provide adequate periodontal support for eruption and preservation of the teeth adjacent to the cleft. Presented here with is a case of unilateral cleft lip and palate, which was followed up from birth to 15 years of age. The role of an orthodontist in the team approach for management of such anomalies is described. Also discussed in detail is the entire range of treatment procedures the child underwent, especially the role of secondary bone grafting.  相似文献   
74.
Craniofacial surgery requires a highly specialized surgical team, appropriate precision delicate instruments, dedicated anesthetist, and upgraded intensive care unit facilities. This type of surgery is undertaken in a large number of congenital problems such as encephalocele, craniosynostosis, hypertelorism, tumors of the craniofacial region, and for craniofacial injuries. We present our experience with craniofacial surgery in 10 patients during a 15-month period at Khoula Hospital, Muscat, Sultanate of Oman. These operations were the first of this kind to be done in this part of the world. This article highlights the need for developing craniofacial units in the Gulf region.  相似文献   
75.
BACKGROUND: Recurrent gingival hyperplasia due to plasminogen deficiency is a rare condition due to fibrin deposition in the connective tissue. Only eight cases have previously been reported in the English literature, and all cases were diagnosed before the age of 35 years. This paper presents an older patient with recurrent gingival hyperplasia due to plasminogen deficiency (hypoplasminogenemia). METHODS: A 59-year-old woman presented with recurrent gingival swelling of 6 years' duration. Multiple biopsies performed at various time periods were histologically reported to be gingival hyperplasia with chronic inflammation. Routine hematoxylin and eosin (H & E) staining and direct immunofluorescence were performed. RESULTS: H & E-stained sections showed subepithelial, eosinophilic, amorphous, acellular deposits. Direct immunofluorescence showed positive staining for fibrin, immunoglobulin (Ig) G, IgA, and IgM. Functional plasminogen and plasminogen activator inhibitor-1 assays were done and found to be deficient. A diagnosis of gingival hyperplasia due to plasminogen deficiency (hypoplasminogenemia) was rendered. CONCLUSIONS: Recurrent gingival hyperplasia due to plasminogen deficiency (hypoplasminogenemia) is a newly recognized and rare condition. H & E staining, direct immunofluorescence, and assessment of functional plasminogen levels are essential to differentiate this condition from other conditions in which subepithelial, eosinophilic, amorphous materials are deposited.  相似文献   
76.
Lichen planus is a dermatologic disease of unknown etiology characterized by keratotic plaques on the skin. Many patients also harbor white lesions of the oral mucosa. The literature contains numerous reports of lichen planus-like lesions evolving in conjunction with the administration of a variety of pharmacologic agents. It is difficult, if not impossible, to distinguish such lesions from one another. The present study evaluated the epithelial and basement membrane thickness, mast cells (intact cells and degranulated cells subepithelially) and the presence or absence of blood vessels in oral lichen planus and oral lichenoid lesions. The evaluation was done using the periodic acid-schiff (PAS) and toluidine blue staining techniques on 20 cases each of oral lichen planus and oral lichenoid lesions and 5 control specimens of normal buccal mucosa. The results showed an increased number of degranulated mast cells in areas of basement membrane degeneration, increased vascularity and increased PAS-positive basement membrane thickness in oral lichen planus as compared with oral lichenoid lesions. Reduced epithelial thickness was found in oral lichen planus. The present study emphasizes the importance of these parameters in differentiating oral lichen planus from oral lichenoid lesions using special staining techniques.  相似文献   
77.

Introduction  

Mandibular defects usually involve a combination of osseous and soft tissue deficiency and are among the most challenging problems in maxillofacial surgery, many options are available for mandibular reconstruction. One of the options discussed in literature recently being distraction osteogenesis.  相似文献   
78.
79.
Carcinomas of the tongue constitute approximately 5% to 10% of oral carcinomas. Rehabilitation of these patients postsurgery is challenging because the motor control of the tongue is lost and postsurgical scarring reduces the vestibular depth needed to support and retain a denture. Implant-supported overdentures are a viable option to rehabilitate such patients. The restoration provides enhanced function and wearer comfort.  相似文献   
80.
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