Gavriel Chaushu

Anterior loop of the mental canal: an anatomical-radiologic study.

This study sought to characterize the anatomical dimensions of the anterior mental loop and to determine the accuracy of conventional radiographs in identifying its presence and dimensions. The study group consisted of 46 hemimandibles fixed in formalin. Radiographs of the area between the mental foramen and the midline were obtained and evaluated for each hemimandible, followed by dissection and physical examination of the same area. Anatomically, an anterior loop of the mental nerve was observed in only 13 hemimandibles (28%). The anterior extension of the loop ranged from 0.4 to 2.19 mm. No correlation was found between the radiographic image and the anatomical shape of the loop. Of the radiographically diagnosed loops, 40% were not seen in anatomical examination. In cases with a false radiologic loop, a correlation was found between the diameter of the origin of the incisive canal and the radiologic interpretation of the loop. The radiologic appearance or diagnosis of the anterior mental loop in cadaver mandibles does not disclose the true ramification of the inferior alveolar nerve to the mental and incisive nerve.

Anatomic and radiologic course of the mandibular incisive canal.

The purpose of this article was to define the anatomic and radiographic courses of the incisive mandibular canal and discuss its clinical significance. The study group comprised of 46 hemimandibles fixed in formalin. After radiographic examination, the buccal cortical plate of the mandible was removed leaving the bony frame of the incisive bundle intact. The morphology of the bony walls of the canal was evaluated, as having complete, partial, or no cortical walls. The course of the intraosseous pathway of the canal and its diameter in four different locations were recorded. An incisive bundle was anatomically found in all hemimandibles, travelling within a canal with complete (n = 10), partial (n = 27), or no (n = 9) bony cortical borders. The diameter of the canal ranged from 0.48 mm to 2.9 mm. Radiographically, the canal was either well defined (n = 11, 24%), poorly defined (n = 15, 32%), or undetectable (n = 20, 44%). A statistically significant correlation was found between the anatomic structure of the incisive canal bony borders and its radiographic detectability (p = 0.043). No correlation was found between the anatomic and radiological width of the incisive canal diameter. An incisive canal with a large diameter could have an important role in successful osteointegration and prevention of postoperative sensory disturbances. According to the present study, the ability to interpret the incisive canal from conventional radiographs is limited. Therefore, it is recommended to use conventional tomographs or computerised tomographic dental scans for better imaging of the intermental foraminal area.

Quality of life of nasopharyngeal carcinoma patients

Quality of life (QOL) issues in patients with head and neck carcinoma are of importance beyond the incidence of these tumors because of the impact of the disease and its treatment on external appearance and function of the upper aerodigestive tract. Nasopharyngeal carcinoma (NPC) patients comprise a unique subgroup in whom, to our knowledge, QOL has not been studied directly.

Risk factors contributing to symptomatic plate removal in orthognathic surgery patients

PURPOSE This study analyzed the fate of miniplates in orthognathic surgery and defined risk factors that eventually result in plate removal. PATIENTS AND METHODS The outpatient clinic files of 70 patients who had undergone orthognathic surgery were reviewed. All osteotomies were rigidly fixed with stainless steel or titanium miniplates. Study variables included age, gender, plate material, site of plates, and reasons for plate removal. RESULTS Of 260 plates used for fixation, 31 were removed (12%). When all factors were considered together, only age was statistically significant. Patients older than 30 years of age were more likely to have plate removal (22% vs. 9%). Only when each factor was considered separately were gender and plate material statistically significant. Females (15.4% vs. 6.7%) and stainless steel plates (15.5% vs. 6.7%) were more prone to plate removal. Although more plates were removed from the buttress (15.5%) and chin (14.5%) compared with the piriform area (6.4%), this was not statistically significant. CONCLUSIONS Age can be defined as a primary risk factor for plate removal, whereas gender and plate material are secondary. Although age and gender are not controllable, the use of titanium plates and infection control may lower the number of symptomatic plates and the need for their removal.

The use of panoramic radiographs to localize displaced maxillary canines.

OBJECTIVE The purpose of this investigation was to develop a reliable method of diagnosing the position of a displaced maxillary canine on the basis of a single panoramic radiograph. STUDY DESIGN A total of 115 panoramic radiographs depicting 164 displaced maxillary canines were evaluated. The ratio of the width of the displaced canine to the width of the homolateral central incisor (the canine-incisor index) and the ratio of the width of the displaced canine to the width of the contralateral canine (the canine-canine index) were calculated. The height of the crown of each displaced canine was classified in the vertical plane, relative to the adjacent incisor, as apical, middle, or coronal. RESULTS There was an overlap in the canine-incisor index ranges of the buccal (0.94-1. 45) and palatal (1.15-1.29) canines in the apical zone. In the middle and coronal zones, a clear difference could be seen between the canine-incisor indices of labially (0.78-1.11) and palatally (1.15-1.7) located canines. A cut-off point of 1.15 was determined. CONCLUSIONS Provided that vertical restriction and the canine-incisor index are used, the panoramic radiograph can serve as a useful indicator for determining the position of an unerupted maxillary canine.

Immediate provisionalization of single-tooth implants in fresh-extraction sites at the maxillary esthetic zone: up to 6 years of follow-up.

Aim:Numerous studies demonstrate successful immediate loading of dental implants. The purpose of this study was to evaluate the long-term survival of single-tooth implants immediately placed in fresh extraction sites at the anterior maxilla with immediate infraocclusion-provisional restorations and nonfunctional immediately loading. Methods:A total of 24 implants were placed in 16 patients. The fixed provisional restorations were connected to a prefabricated plastic abutment. Occlusal contacts were avoided. Follow-up starting at implantation day ranged from 24 to 72 months with a mean of 40.7 months. Results:One implant failed 1 month after placement due to the unscrewing of a temporary abutment that resulted in implant overload. Overall implant survival rate resulted in 95.8%. The mean marginal bone loss increased by 0.9 ± 1.1 mm. starting from implant placement. Conclusions:Within the limits of this study, the data indicate that nonfunctional immediate loading of single-tooth implants placed in fresh extraction sites in the anterior maxilla can result in successful implant integration and stable peri-implant conditions up to 6 years.

The Effect of Crown/Implant Ratio and Crown Height Space on Stress Distribution in Unsplinted Implant Supporting Restorations

PURPOSE To measure the transfer of axial and nonaxial load in unsplinted fixed implant supported restoration with varying crown to implant (C/I) ratios and crown height space (CHS). MATERIALS AND METHODS A photoelastic block model was constructed. Three holes were drilled vertically in a straight line in the mid axis of the photoelastic model at predetermined locations to lengths of 12 mm. Three implants were inserted into the model. Two strain gauges were cemented onto the neck of each implant on the buccal and lingual aspects, which provided a simultaneous direct reading of strain. Four groups of cement retained restorations with C/I ratios of 1:1; 1:1.5; 1:1.75, and 1:2 were used. CHS were 10, 15, 17.5, and 20 mm, respectively. Fifteen static loadings were carried out simultaneously with 20 kg weights via a custom-built loading apparatus at 0 and 30 degrees to the vertical axis. Descriptive analysis consisted of mean and standard deviation of microstrain values for each group. Groups were compared by the use of the 1-way parametric analysis of variance. A P value of less than .05 was considered statistically significant. RESULTS Occlusal force application at 30 degrees showed a statistically significant increase in both buccal (1,588 ± 150 vs 2,610.59 ± 150) and palatal (64.92 ± 7 vs 146.59 ± 15) microstrain values as C/I ratio increased from 1:1 to 1:1.5 (P < .001). Force application at 30 degrees in cases with C/I ratio of 1:1.75 and 1:2 resulted in fracture of the abutment screw followed by dislodgment of the crowns. Failures were noted at CHS >15 mm. CONCLUSIONS CHS is more significant than the C/I ratio in assessing biomechanical-related detrimental effects. Prosthetic failure occurred at CHS ≥ 15 mm.

Salivary LL-37 Secretion in Individuals with Down Syndrome is Normal

Antimicrobial peptides play an important role in the innate immune response. Deficiency in salivary LL-37 antimicrobial peptide has been implicated in periodontitis in patients with morbus Kostman syndrome. Down syndrome is associated with periodontitis, diminished salivary flow, and salivary immunoglobulin deficiency. In the present study, levels of LL-37 and its hCAP18 precursor were measured in saliva samples from young individuals with Down syndrome and compared with levels in those from age-matched healthy controls. LL-37 and human cathelicidin antimicrobial protein (hCAP18) were detected in whole but not in parotid saliva. hCAP18 was more abundant than LL-37. The concentrations of salivary hCAP18 and LL-37 were found to be higher in individuals with Down syndrome than in healthy controls, but their secretion rates were similar. We concluded that, while the adaptive immunity of individuals with Down syndrome is impaired at the oral mucosa, the secretion rate of the LL-37 component of the innate immune system is normal.

Risk factors contributing to symptomatic plate removal in maxillofacial trauma patients.

This study analyzed the fate of plates used to correct maxillofacial injuries and defined risk factors that eventually resulted in plate removal. The outpatient clinic files of 108 patients treated with rigid internal fixation after maxillofacial trauma were reviewed. Study variables included age, sex, trauma circumstances, diagnosis, type of fracture, approach to the facial skeleton, presence of teeth in the line of fracture, plate material, site of plates, and reasons for plate removal. Of 204 plates used for fixation, 44 plates (22 percent) were removed. When all factors were considered together, only fracture diagnosis (mandibular body and angle) and plate location (mandibular body and angle) were statistically significant. Only when each factor was considered separately, the approach to the facial skeleton (intraoral) and the type of fracture (comminuted and compound fractures) were statistically associated with plate removal. Selection of favorable plate location, the extraoral approach, and vigilant infection control may reduce plate removal in patients with maxillofacial injuries. Special attention should be given to compound and comminuted fractures of the mandibular body and angle.

Severe Impairment of Secretory Ig Production in Parotid Saliva of Down Syndrome Individuals

Infections associated with Down Syndrome (DS) are prevalent in the mucosal-gastrointestinal and respiratory systems, for reasons that are uncertain. The purpose of the present study was to assess the levels of parotid salivary immunoglobulins (Ig) in a group of DS individuals as a possible factor in the susceptibility of mucosal surfaces to infections. Twenty-nine DS and 10 age- and sex-matched healthy individuals were included. Salivary flow rate and IgA, IgG, and IgM concentrations were recorded. The secretion rates of IgA and IgG were diminished by 83% (p < 0.001) and 75% (p = 0.05), respectively, whereas the secretion rate of IgM was not statistically significantly lower. Analysis of the data suggests that DS individuals are immunodeficient in the humoral mucosal immune response. This may explain, in part, the high incidence of recurrent infections in target organs of the secretory immune system in DS subjects.