PubMed Health⌕ Search

Biomedical subjects

A Rachmiel

Publications and source records attributed to A Rachmiel.

At least 19 recordsLinked to original sources

Bilateral mandibular distraction for patients with compromised airway analyzed by three-dimensional CT.

The purpose of this study was to present the method of mandibular distraction osteogenesis in order to improve airway to respiratory distressed patients due to significant mandibular deficiency, and to present the quantitative volumetric evaluation of mandible and upper airway using three-dimensional-CT (3D-CT) before and after distraction. This study involved 12 patients aged 12 months to seven years with various complaints of Obstructive Sleep Apnea (OSA) such as noisy breathing during sleep, waking episodes, pauses in respiration and daytime somnolence. Some of them were considered tracheostomy candidates. All the patients underwent bilateral mandibular distraction under general anesthesia. 3D-CT of face and neck was performed before and after distraction and a quantitative volumetric evaluation of mandibular volume and airway volume was performed. The results reveal successful mandibular advancement with increase of mandibular volume by an average of 28.24% and increase of upper airway volume with a mean of 71.92%. Moreover, there were improved apnea index and oxygen saturation and elimination of OSA symptoms. In conclusion, the results demonstrate that following distraction osteogenesis of hypoplastic mandible the volume of the mandible and upper airway increases, eliminating symptoms of OSA and preventing tracheostomy.

Child↗

Long-term results in maxillary deficiency using intraoral devices.

Cleft lip and palate patients often present maxillary retrusion and class III malocclusion after cleft repair. Maxillary distraction is a technique that can provide simultaneous skeletal advancement and expansion of soft tissue. Twelve patients with cleft maxillary deficiency due to cleft lip and palate were treated by Le Fort I osteotomy and two intraoral distraction devices that were activated after 4 days of latency period, 1mm per day on both sides. Long-term clinical and cephalometric evaluation of one and two years demonstrate stable results concerning the skeletal, dental and soft tissue relations. In this paper we discuss the advantages of distraction osteogenesis as a method for treatment of maxillary deficiency in cleft patients in terms of stability and relapse. The indications for maxillary distraction: (1) Moderate and severe retrusion that needs large advancement as in cleft lip and palate patients. (2) Forward and downward lengthening of the maxilla with no need for intermediate bone graft. (3) Growing patients. In conclusion, maxillary distraction in moderate or severe retrusion, as in cleft patients offers marked maxillary advancement with long-term stability.

Adolescent↗

Bone defect repair in rat tibia by TGF-beta1 and IGF-1 released from hydrogel scaffold.

Bone repair is one of the major challenges facing reconstructive surgery. Bone regeneration is needed for the repair of large defects and fractures. The ability of TGF-beta1 and IGF-1 incorporated into hydrogel scaffold to induce bone regeneration was evaluated in a rat tibia segmental defect model. External fixation was performed prior to the induction of the segmental bone defect in order to stabilize the defect site. Hydrogel scaffold containing either TGF-beta, IGF-1, TGF-beta + IGF-1, hydrogel containing saline or saline, were inserted in the defect. Calcified material was observed in the defects treated with TGF-beta 2 weeks following the start of treatment. Bone defects treated with TGF-beta, IGF-1 or TGF-beta + IGF-1 revealed significant bone formation after 4 and 6 weeks when compared to the control specimens. X-ray images showed that solid bone was present at the defect site after 6 weeks of treatment with TGF-beta or TGF-beta + IGF-1. A less pronounced bone induction was observed in the control specimens and bones treated with IGF-1. Percent closure ratio of bone defects after 6 weeks were 40, 80, 89, and 97% for saline, hydrogel, IGF-1, TGF-beta and IGF-1 + TGF-beta groups, respectively. It is concluded that hydrogel scaffold can serve as a good osteoconductive matrix for growth factors, and that it provides a site for bone regeneration and enhances bone defect healing and could be used as alternative graft material.

Animals↗

[Pre-septal orbital cellulitis from odentogenic origin--combined surgical and endodontic approach: a case report].

Orbital abscesses are common infectious diseases. The etiology of orbital abscesses may vary from common sinusitis in most of the cases, to cocaine sniffing. As a result of the proximity to the brain, orbital abscesses may complicate to life threatening situations. The infectious process spreads to the orbit in several ways: hematogenous, via anatomic spaces in the maxillofacial region, direct invasion. The treatment philosophy combines surgical and Antibiotic therapy to resolve the acute phase of the disease, followed by elimination of the source. The purpose of this paper is to report a case of pre septal orbital cellulitis, that was treated surgically combined with endodontic therapy. To describe the different subtypes of orbital abscesses, differential diagnosis, imaging and treatment options.

Adolescent↗

Use of the 'shark-fin' osteotome in separation of the pterygomaxillary junction in Le Fort I osteotomy: a clinical and computerized tomography study.

Le Fort I osteotomy fails in many cases to completely separate the pterygomaxillary junction and often results in fractures of the pterygoid bone and the tuberosity, which subsequently can cause complications. The objectives of this study were to describe the specifically developed Laster 'shark-fin' osteotome and to compare its use to other methods of pterygomaxillary dysjunction. Pterygomaxillary dysjunction was performed in 10 adult patients requiring Le Fort I osteotomy. In one randomly chosen side of the maxilla, the Obwegeser osteotome was used, while the Laster 'shark-fin' osteotome was used on the opposite side. A postoperative computerized tomography of the separation at the pterygomaxillary junctions revealed that in all sites treated with the Laster 'shark-fin' osteotome, a complete or almost complete separation was obtained, whereas the use of the Obwegeser osteotome resulted in five sites with fractures of the maxillary tuberosity and three with high-level fractures of the pterygoid plates (P<0.001). Comparing these findings with the literature, we concluded that the Laster 'shark-fin' osteotome is preferable for separating the pterygomaxillary junction in Le Fort I osteotomy.

Adolescent↗

Osseous reconstruction using a membrane barrier following marginal mandibulectomy: an animal pilot study.

BACKGROUND: Invasive and malignant tumors of the oral soft tissues adjacent to the mandible are often treated with partial resection of the osseous structure adjacent to the lesion (marginal mandibulectomy). Autogenous bone graft and composite bone grafts are being used to fill the osseous defects with various degrees of success. The aim of the present study was to explore the utilization of membrane barriers and the principle of guided bone regeneration to negotiate these defects. METHODS: Following the removal of P1, P2, and P3, experimental bilateral marginal mandibulectomy defects were created in 4 adult dogs. The bone segments (measuring 25 mm x 15 mm) were then removed. Each side was then randomly selected for either experimental (titanium-reinforced expanded polytetrafluoroethylene membrane, [ePTFE-TR]) or control (repositioning flaps) treatment. Postoperatively, the animals were put on soft diet, antibiotics, and analgesics. Sutures were removed under light sedation after 4 weeks, and the area was left to heal and mature for 4 to 6 months (mean 5.3 months). The animals were then sacrificed, and block sections of the mandible were obtained for macroscopic and histological evaluation. RESULTS: The size of the residual defect (the vertical distance between the most apical depression in the ridge and the horizontal line connecting the free gingival margins of the proximal teeth) in the experimental sites (6.10 +/- 1.00 mm) was much smaller compared to the controls (10.65 +/- 0.82 mm), which was statistically significant (P = 0.0127). Histomorphometric measurements of new bone formation (NBF) revealed a similar pattern: for the experimental sites, NBF was 8.08 +/- 0.85 mm compared to 4.99 +/- 0.61 mm in the controls. These differences were also statistically significant (P = 0.0257). CONCLUSIONS: A regenerative approach to large mandibular osseous defects has been described. If this new treatment modality is further substantiated in other independent studies, it might prove a useful tool in restoring the lost osseous structure associated with marginal mandibulectomy procedures.

Animals↗

Expression of vascular antigens by bone cells during bone regeneration in a membranous bone distraction system.

An in vivo system of membranous bone formation during distraction has been investigated in order to follow cells that express vascular markers with the objective of understanding the neovascularization process. Concomitantly, sustained proliferation of preskeletal cells was achieved through the application of mechanical force. New capillaries and leading edges that arose by angiogenesis from the periosteal and mucosal surfaces and invaded the central zone of the regenerating distraction tissue temporally preceded the growth of delicate woven bone trabeculae from both edges of the cut bone. Concentrically arranged 'onion-like' configurations were abundant in paracentral zones and in association with mesenchymal condensations, suggesting their de novo formation in situ. Vascular specific markers, the angiopoietin receptor Tie-2 and factor VIII-related antigen (FVIIIrAg), were localized immunohistochemically in order to follow cells of vascular origin. Endothelial cells of the new capillaries, centrally located cells of the concentric configurations, pericytes, and most of the adjacent polygonal mesenchymal cells stained positively with specific antibodies to both antigens. Moreover, preosteoblasts and osteoblasts that lie adjacent to or already embedded in the osteiod of the newly formed trabeculae were also FVIIIrAg and Tie-2 immunopositive. As the source of the bone-forming cells in regenerating tissue during distraction is not yet fully understood, this observation might support the possibility of their vascular origin.

Animals↗

Intraoral distraction osteogenesis of the mandible in hemifacial microsomia.

PURPOSE: Lengthening of the mandible by distraction osteogenesis is the preferred method for treatment of hemifacial microsomia in children. Use of an intraoral distraction technique and horizontal oblique ramus osteotomy in such patients is presented. PATIENTS AND METHODS: Mandibular ramus lengthening was performed in 11 patients aged 6 to 12 years with hemifacial microsomia. During the age of mixed dentition in hemifacial microsomia patients with a hypoplastic mandible, the unerupted molars buds are located high in the retromolar region and are in danger of being damaged by the osteotomy. Therefore, an intraoral approach exposing the mandibular ramus and angle was performed, and a horizontal oblique ramus osteotomy was made, preserving the inferior alveolar nerve. An intraoral device was placed along the ramus, and distraction was started on the third postoperative day at the rate of 1 mm/d and continued for 2 to 3 weeks or as long as necessary. The device was maintained for retention an additional 6 weeks and was then removed. RESULTS: Clinically, the face became more symmetric. The postdistraction posteroanterior cephalometric radiographs demonstrated elongation of the affected ramus and improvement in facial symmetry. CONCLUSIONS: The advantages of this method are that it allows device placement along the ramus, permitting the ramus elongation necessary in treatment of hemifacial microsomia, that it prevents damage to the tooth buds which, during the age of mixed dentition, are in a higher position in the retromolar area, and that it prevents injury of the inferior alveolar nerve.

Cephalometry↗

Alveolar ridge augmentation by distraction osteogenesis.

Distraction osteogenesis is an alternative method for reconstructing atrophic alveolar bone. Fourteen patients underwent vertical alveolar distraction by the LEAD SYSTEM-Endosseous Alveolar Distraction System (Stryker Leibinger, Kalamazoo, MI). An alveolar segmental osteotomy was carried out and the vertical distraction device was mounted. In patients with an extensive alveolar defect, two distraction devices were placed in order to better control the vector of elongation in both bone edges. The distraction was started on the fourth postoperative day at a rate of 0.8 mm/day for 10-16 days, followed by a consolidation period of 60 days. Vertical distraction osteogenesis (VDO) was completed successfully in all patients with segment lengths in the range of 8 to 13 mm and with an average of 10.3 mm. Subsequently, the devices were removed and 23 threaded titanium dental implants were placed for osteointegration. Earlier mineralization in the vertically distracted area was seen radiographically during the consolidation period. In a follow up of 6-20 months after the distraction, 22 implants were successfully osteointegrated while one implant failed due to improper distracted segment stability. As a result of alveolar distraction, a segment of mature bone was transported vertically in order to lengthen the crest for better implant anchorage, either for aesthetic purposes or for functional prosthetic requirements. The main advantages of VDO are: (1) augmentation of alveolar bone height with new bone formation and simultaneous expansion of the soft tissues; (2) no bone harvesting is necessary; (3) the technique has a lower morbidity rate compared with conventional techniques; (4) it makes the insertion of longer dental implants feasible.

Adolescent↗

[Vertical alveolar ridge augmentation using distraction osteogenesis].

Alveolar ridge atrophy can be acquired or congenital. Alveolar ridge augmentation can be performed using bone grafting but a donor site morbidity is unavoidable and some resorption of the grafted bone occurs. Distraction osteogenesis offers an alternative method for bone reconstruction without donor site morbidity and sufficient stability of the final results. In order to place implants, vertical alveolar augmentation using Distraction Osteogenesis has been applied to 14 patients aged 17 to 55 years old with edentulous alveolar ridge, 8 in the mandible and 6 in the maxilla. Vertical alveolar bone distraction was started by performing a segmental alveolar osteotomy followed by insertion of a central distraction device--Lead System (Endosseous alveolar distraction system, Leibinger). After three days of latency period, the distraction was started in a rate of 0.8 mm per day for 9 to 16 days as needed. The retention period for the new bone maturation was twice as long as the active distraction period. After removal of the device, 23 cylindrical threaded implants were inserted. The results revealed increase of the alveolar bone height with new bone formation that was observed radiographically and clinically at the removal of the distraction device. The amount of elevation was 7-13 mm. In follow-up of 6-14 months, failure of only one implant was noted, due to inadequate transported bone stability. The advantages of alveolar bone distraction are: Increase of the alveolar bone height with new bone formation, minimal resorption of bone without the bone graft disadvantages. A long term follow up after the bone height achieved and implant anchorage should be performed in the future.

Adolescent↗

Carcinoma of the dorsum of the tongue.

BACKGROUND: Squamous cell carcinoma (SCC) of the anterior two thirds of the tongue is the second most common oral cancer, with the lateral border being the most common location. Squamous cell carcinoma of the dorsum of the tongue is exceedingly rare and has been described in the past as a myth or misdiagnosis. The clinical diagnosis of SCC on the dorsum of the tongue is difficult because it may be mimicked by a wide variety of benign and premalignant lesions, including granular cell myoblastoma, erosive lichen planus, medial rhomboid glossitis, and amyloidosis. In this study we re-evaluate the entity of SCC of the dorsum of the tongue. METHODS: We reviewed 5 large series of carcinoma of the tongue, which include accurate documentation of the topographic location of the carcinoma. We also describe 5 cases of SCC of the dorsum of the tongue from our own series of 99 patients with carcinoma of the tongue. RESULTS: In all 6 series, carcinoma of the dorsum of the tongue was present in 3 to 5% of the carcinomas of the tongue. CONCLUSION: Although rare, SCC of the dorsum of the tongue exists and may be mimicked by benign conditions, thus SCC should be suspected when diagnosing lesions of this area of the tongue.

Adult↗

Interleukin-6 modulates trabecular and endochondral bone turnover in the nude mouse by stimulating osteoclast differentiation.

A great deal of evidence has been accumulating that implicates the immune system in normal and pathological bone turnover. The objective of the present study was to examine the possible involvement of cytokines produced by T lymphocytes in bone metabolism. We have chosen the immunologically compromised athymic mouse, which demonstrate sclerotic features in its trabecular bone, as the animal model for assessment of possible modulation effects of interleukin-1alpha (IL-1alpha) and interleukin-6 (IL-6) on bone and cartilage metabolism. The cytokines were applied by daily subcutaneous injections for 3 consecutive days. Histomorphometry, measuring epiphyseal trabecular bone volume (ETBV), metaphyseal trabecular bone volume (MTBV), and the width of the growth plate, and tartrate-resistant acid phosphatase (TRAP) histochemistry were used to assess parameters of bone turnover in the proximal tibia. IL-6, but not IL-1alpha, reduced ETBV and MTBV. Both IL-6 and IL-1alpha reduced the width of the growth plate. IL-6, but not IL-1alpha, increased the number of chondroclasts and osteoclasts in the primary spongiosa of the proximal tibia, as well as the number of nuclei. The resultant bone resembled that of the wild-type mouse. The results point to IL-6 as a possible regulator of bone turnover in vivo. It is suggested that the athymic mouse has a deficiency somewhere in the cascade of events leading to the production of IL-6 or, alternatively, that IL-6 replaces other factors that are supplied by T lymphocytes directly or indirectly. As T lymphocytes interact with B lymphocytes it is suggested that the athymic mouse might be appropriate for studying the in vivo effects of the immune system on normal bone metabolism.

Animals↗

Extraoral vs. intraoral distraction osteogenesis in the treatment of hemifacial microsomia.

During hemifacial microsomia (HMF), an important phase of the treatment is elongation of the hypoplastic mandible, mainly the ramus, at an early stage. Twenty-two patients with HFM were treated with distraction osteogenesis: 12 with an extraoral device (10 unidirectional and 2 multidirectional) and 10 with an intraoral device. The mean elongation with the extraoral device was 21 mm, and with the intraoral device was 17 mm, resulting in a more symmetrical facial appearance. The advantages and disadvantages of both methods are presented, based on the authors' experience and a review of the literature. The extraoral device permits elongation of a greater distance, enables extraoral control of the vector of elongation, and conserves the gonial angle by working in many directions. The main disadvantages of the extraoral device are the social inconvenience to the patient and the extraoral cutaneous scars. Conversely, the intraoral device is much more socially convenient to the patient and avoids residual scarring. However, in 2 patients treated with an intraoral device, an undesired contralateral open bite appeared as a result of reduced vector control. The intraoral method should always be considered first because of its previously mentioned advantages. However, in severely hypoplastic patients, when three-dimensional correction and gonial angle control are necessary, or when there is a limited space along the planned distracted bone, the extraoral device has an advantage over the intraoral device.

Adolescent↗

A possible otological complication due to maxillary expansion in a cleft lip and palate patient.

OBJECTIVE: We present a possible negative side effect of a sudden onset of secretory otitis media in a 12-year-old boy with unilateral cleft lip and palate who underwent maxillary expansion. The secretory otitis media caused a temporary hearing loss developed during the activation of the expander appliance. The possible causes for this complication are discussed. CONCLUSIONS: Clinicians should be aware of the possible association between maxillary expansion and secretory otitis media.

Audiometry, Pure-Tone↗

Primary gingival malignant melanoma. Report of 3 cases.

BACKGROUND: Malignant melanoma is rare in the oral cavity and accounts for less than 1% of all melanomas. Nevertheless, the disease can be fatal, and early diagnosis and treatment may improve prognosis dramatically. The purpose of this paper is to report 3 new cases of primary malignant melanoma of the oral cavity arising in the gingiva, and to review the literature regarding intraoral melanoma. METHODS: Three cases are presented. One case was in the right mandibular molar area; the second in the right maxillary canine-premolar area; and the third in the left mandibular canine-premolar region. All patients were treated surgically, with postoperative radiotherapy. RESULTS: The first patient lived for 2 years and the second for 3 years before distant metastases were diagnosed from which they subsequently died. The third patient was lost from follow-up after 18 months. CONCLUSION: Primary oral malignant melanoma is a deadly disease. Early suspicion of this disease will allow prompt treatment and increase the prognosis for these patients.

Adult↗

[Secondary bone grafting in cleft lip and palate].

Results of reconstruction of residual alveolar bone defects in 52 patients operated between 1990-1998 were evaluated clinically and radiographically in a retrospective study. Ages ranged between 9-37; 30 were males. The donor site of bone grafts in all was particulate cancellous marrow from the anterior iliac crest. 32 had unilateral clefts and 20 bilateral. Total cleft sites treated was 72. Best results were achieved when bone grafting was carried out prior to the eruption of the canine tooth. The cleft space was closed and oro-nasal fistulas were eliminated in 42 (80%). Success rates in unilateral and bilateral cases were significantly different.

Adolescent↗

Clinical and radiographic features of eosinophilic granuloma in the jaws: review of 41 lesions treated by surgery and low-dose radiotherapy.

Eosinophilic granuloma within the jaws may radiographically mimic other benign odontogenic cysts and tumors, and different protocols have been suggested in the literature for treating eosinophilic granuloma of the jaws. Forty-one lesions of eosinophilic granuloma, diagnosed in 25 patients, were reviewed retrospectively, and data were collected regarding age, gender, ethnic origin, location, symptoms, clinical appearance, radiographic features, treatment, and recurrence. The lesions were found in youngsters (18.1 +/- 4.7 years of age), mostly in the posterior parts of the mandible, and the most common presenting symptom was pain (92%), often accompanied by swelling. Approximately one half of the lesions were radiographically well defined without ossification. All patients were treated by enucleation (with or without peripheral ostectomy) and radiotherapy; 7.3% lesions recurred during follow-up (9.3 +/- 4.6 years). In addition, the different treatments suggested in the literature for eosinophilic granuloma of the jaws were reviewed.

Adolescent↗