Biomedical subjects
Publications and source records attributed to M Peled.
The incidence of lipoma in the parotid gland is very low, and lipomas in the deep lobe of the parotid are extremely rare and seldom considered in the differential diagnosis of deep lobe parotid gland tumours. A deep lobe parotid gland lipoma is presented and discussed.
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.
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.
Several conflicting findings have been published in previous literature regarding the effects of impacted third molar extraction on the periodontal health of the adjacent second molar; some authors have shown improvement of periodontal health distal to the adjacent second molar, whilst others have demonstrated loss of attachment and reduction of alveolar bone height. The purpose of this controlled clinical and radiographic study is to evaluate the long-term changes in periodontal health and alveolar bone height distal to the adjacent second molar following extraction of an impacted third molar. This split-mouth design study included 25 patients who underwent extraction of one mandibular impacted third molar (test), whereas the opposite tooth remained intact (control). Pre-operative and current-state panoramic radiographs were than scanned, and alveolar bone height was digitally measured on the distal aspect of the second molar on the test and control sides. Current-state clinical measurements were performed on both sides, and consisted of plaque index, gingival index, periodontal pocket depth, gingival margin position and clinical attachment level. Student's t-test for paired observations was used in order to examine the statistical significance of the differences in clinical parameters between the test and control sides and the differences in alveolar bone height pre- and post-operatively on both sides. Extraction of an impacted third molar resulted in a significant gain of alveolar bone height on the distal aspect of the adjacent second molar on the test side, whereas slight bone loss was noted on the control side. Even though the difference in plaque index between the test and control sides approached statistical significance following extraction, all clinical parameters seem to be unchanged. Further follow-up on clinical and radiological parameters is required for a more profound understanding of the long-term effects of third molar extraction on the periodontal health of the adjacent second molar.
BACKGROUND: Individuals with intellectual disability (ID) are more vulnerable to abuse compared to individuals without disabilities yet have limited access to the legal system. This study examined perceived credibility of youth with mild intellectual disability (MID) who provide courtroom testimony. METHOD: Participants, 187 undergraduates, were asked general questions about credibility. They also read eyewitness testimony and answered questions about a particular witness's credibility. Half the participants were informed that the youth has MID [chronological age (CA) 15 years, mental age (MA) 10 years] and the others were informed that the youth is a typically developing 10-year-old. RESULTS: When participants were asked general questions about credibility they rated 15-year-olds with MID (MA 10 years) as less credible than typically developing 15-year-olds and as less credible than typically developing 10-year-olds. However, when participants read eyewitness testimony and answered questions about a particular witness's credibility, no statistically significant differences were found between participants who were informed that the witness was a 15-year-old with MID (MA 10 years) and those who were informed that the witness was a typically developing 10-year-old. CONCLUSIONS: The present study provided a preliminary investigation of perceived credibility of witnesses with MID and suggests directions for future research in this area.
Replacing missing teeth with osseointegrated dental implants is a predictable technique as evidanced by overall 5-years survival rate that range between 93% to 97%. Few studies, however have adressed the history and frequency of inflammatory complication associated with dental implant. Inflammatory complications are the main cause of failure of dental implants. In this review we classified the inflammatory complications to acute and chronic and to those limited to the hard tissue, to the soft tissue or both. The incidence of the complications is discussed with an emphasis on their risk factors.
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.
Eagle syndrome is an aggregate of symptoms that includes recurrent throat pain, foreign body sensation, dysphagia, and/or facial pain as a direct result of an elongated styloid process or calcified stylohyoid ligament. The etiology is poorly understood and several theories have been proposed. The pathophysiological mechanism of symptoms is debated as well. Diagnosis is made both radiographically and by physical examination. Treatment of Eagle syndrome is either surgical or non surgical. A case report of temporomandibular joint pain that has been finally diagnosed as Eagle syndrome is presented and discussed.
An integral component of apicoectomy procedure is the placement of a root end filling material. In this 20 years literature review we identified at least 19 different materials that have been used as root end filling materials. Unfortunately, the ideal material for this purpose is yet to be found. Amalgam is the most frequently used material in apicoectomy procedure and can lead to satisfying results in many cases. IRM, super EBA and MTA are more suitable materials, and give better results in apicoectomy procedures than Amalgam. IRM and super EBA are both ZOE cements. Super EBA is less cytotoxic than IRM, suggesting that the decreased eugenol in Super EBA allows it to be less irritating. MTA gives better results when tested for leakage and biocompatibility than IRM and Super EBA, and has the ability of induction of hard tissue. A possible disadvantage that prevents MTA from being acceptable as "the ideal root-end filling material" is a long setting time that may lead to dislodgment or deformation from root end preparation. Yet, in most cases MTA serves as the best choice for a root end filling material.
Replacing missing teeth with osseointegrated dental implants is a predictable technique as evidenced by the overall five-year implant survival rates ranging 93% to 97%. Few studies, however, address systematically the frequency or natural history of complications related to the use of dental implants. Reported complication rates range so widely, i.e. 1%-40%, as to be rendered clinically meaningless. Differences in reported rates may be attributable to differing definitions of complications. Even less has been written about risk factors for developing surgical complications related to the use of dental implants. Knowledge regarding the type and frequency of complications that can occur with implants is an important aspect of treatment planning, surgeon-patient communication, informed consent and post-treatment care. The purposes of this chapter are to: 1) summarize the reported types and frequencies of implant-associated complications, 2) identify risk factors for developing complications associated with the use of dental implants, and 3) to suggest strategies to avoid complications.
Immediate loading of dental implants aims to shorten treatment time. Stability at implant insertion is critical to success. The aim of this prospective study is to compare primary implant stability, measured by insertion torque (IT) with resonance frequency analysis (RFA) expressed as ISQ. Patients requiring implant therapy were treated by teeth extractions, placement of 1-9 MIS implants, bone augmentation as needed and fixed provisional restorations. We measured IT and ISQ for non-submerged loaded (NSL), non-submerged non loaded (NSNL) and submerged (S) implants. 14 patients, aged 34-79 years, were recruited. 53 implants were inserted (38 maxillary & 15 mandibular). 30 implants, 18 in fresh extraction sites, were immediately loaded. ISQ was 63.3 +/- 2.8 (S.E.), 67.2 +/- 3.5 (S.E.) and 58.8 +/- 2.7 for the NSL, NSNL and S groups, respectively (p = 0.0459). IT was 40.4 +/- 1.8 Ncm, 46 +/- 4.0 and 35.3 +/- 2.1 (p = 0.0646). ISQ and IT were not statistically different between extraction vs. non-extraction and augmented vs. non-augmented sites. We found a significant difference in IT between maxillary & mandibular sites, and a significant correlation between ISQ & IT and between ISQ & implant diameter. These data suggest that ISQ is correlated to IT and is influenced mainly by implant diameter and not by implant length, location or bone level. Finally, a case including immediate implants, bone augmentation and immediate provisional restoration is presented.
BACKGROUND: Alveolar bone is particularly sensitive to increased levels of parathyroid hormone (PTH) from either primary or secondary hyperparathyroidism (HPT). The purpose of this study was to examine the effect of secondary HPT on the periodontium of patients on hemodialysis. METHODS: The experimental group consisted of 35 patients with secondary HPT, with chronic renal failure treated by hemodialysis (E group). A control group (C group) was formed from 35 healthy age- and gender-matched subjects attending the maxillofacial outpatient clinic for a variety of reasons. Blood samples were taken from the E group, and the biologically active intact parathormone molecule, PTH(1-84), was assayed using two-site immunoradiometric assay (IRMA). The time of onset and the duration since diagnosis of HPT was also recorded. In addition, for a subgroup of 25 matched pairs of patients, a clinical periodontal examination was performed, and the Ramfjord index teeth were recorded for: Plaque index (PI); Gingival index (GI); Probing depth (PD); and Clinical attachment level (CAL). A standardized panoramic X-ray was taken from all patients and computer-based linear measurements were used to assess alveolar bone loss (BL). Unpaired Student's t-test served to compare the two groups. Pearson's correlation coefficient test was used to study the association between PI, PTH level, disease duration and BL. RESULTS: Demographically, both groups were similar with no statistical difference. PI was also similar in the C and E group (2.03 +/- 0.13 and 1.76 +/- 0.17, respectively). GI, however, was slightly greater in the C group (1.28 +/- 0.09) compared to the E group (0.97 +/- 0.01). PD in the E group (2.92 +/- 0.14 mm) was almost identical to that of the C group (2.90 +/- 0.12 mm). Likewise, CAL in the E group (4.43 +/- 0.29 mm) did not differ from CAL in the C group (4.03 +/- 0.25 mm). Mean BL was also similar in the E and C groups (3.60 +/- 0.23 mm and 3.85 +/- 0.24 mm, respectively). PI showed a positive, significant correlation with BL (r = 0.457, P = 0.0008). CONCLUSION: From this study it can be concluded that secondary HPT does not have an appreciable effect on periodontal indices and radiographic bone height.
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.
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.
Saliva plays an important role in maintaining the oral and the dental health, by lubricating the mucosae and protecting the teeth from caries attack. Furthermore, saliva participates in the taste sensation and recognition processes and is a central component in the first stage of the food digestion. Saliva collection, either in the pure or in the whole form, is a relatively easy procedure. Since the collection is non invasive, it is not harmful to the patient and has no complications. The paper discusses the use of saliva in the diagnosis of oral and systemic diseases and in monitoring the levels of molecules like hormones and medicines. The experience accumulated in our department in that field is also presented.
Dental implants are a functional and esthetic solution to partial and total edentulism. The initial success rate of this treatment modality is 90-95%. But, that treatment modality is not free of complications. One of the rare complications yet, with severe clinical results is fracture of dental implants. The current literature review presents the various causative factors that may lead to implant fracture. Implant failures may be sorted into groups by the timing of their appearance, or by the origin of failure. Fractures belong to the group of late complications, caused by a biomechanical overload. Overload may be caused by inappropriate seat of the superstructure, in-line arrangement of the implants, leverage, heavy occlusal forces (bruxing, clenching), location of the implant and the size of the implant or metal fatigue. Good clinical examinations and correct treatment plans may reduce the risk of implant fracture.
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.
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.