Finite element analysis of the stability of retrograde intramedullary nail and plate-screw combinations for periprosthetic femoral fractures following total knee replacement.

OBJECTIVE: Periprosthetic fractures following total knee replacement are rare but challenging. The goal of the treatment is to achieve the most stable fixation that allows early mobilization. Therefore, the aim of this study was to evaluate the biomechanical results of the use of different fixation systems in the treatment of distal femur periprosthetic fractures with finite element analysis. MATERIALS AND METHODS: A total knee prosthesis was implanted in Sawbone femur models. A transverse fracture line was created in the supracondylar region and was fixed in four different groups. In group 1, fracture line fixation was fixed using retrograde intramedullary nailing. In group 2, fixation was applied using a lateral anatomic distal femoral. In group 3, in addition to the fixation made in group 1, a lateral anatomic distal femoral plate was used. In group 4, in addition to the fixation made in group 2, a 3.5 mm Limited Contact Dynamic Compression Plate (LC-DCP) was applied medially. Computed Tomography (CT) scans were taken of the created models and were converted to three-dimensional models. Axial and rotational loading forces were applied to all the created models. RESULTS: The least deformation with axial loading was observed in the double plate group. Group 3 was determined to be more advantageous against rotational forces. The greatest movement in the fracture line was found in group 2. The application of the medial plate was determined to reduce the tension on the lateral plate and increase stability in the fracture line. CONCLUSIONS: Combining a lateral anatomic plate with intramedullary nailing or a medial plate was seen to be biomechanically more advantageous than using a lateral plate or intramedullary nailing alone in the treatment of distal femoral periprosthetic fractures.

Management of anesthesia in pregnant women with pulmonary hypertension.

OBJECTIVE: Pulmonary hypertension (PH) is a rare heart disease associated with high maternal and fetal mortality. This study aims to discuss anesthesia management and the fetal and maternal outcomes of patients with PH followed-up at our clinic. PATIENTS AND METHODS: This study includes a retrospective analysis of 105 pregnant women with PH. The patients were classified according to the mean pulmonary artery pressure (mPAP) values measured at rest by transthoracic echocardiography. The first group included patients with an mPAP value between 25 and 49 mmHg, considered to have a mild PH, whereas patients with an mPAB value ≥50 mmHg were considered to have severe PH and were included in the second group. RESULTS: When the patients were examined for etiology, the majority (n=84, 70.5%) were found to have type 2 PH. It was found that in pregnant women with severe PH, the diameters of the left atrium, right atrium, and right ventricle were significantly larger (p=0.008, p=0.04, and p=0.013, respectively), and the ejection fraction was also significantly lower (p=0.04). CONCLUSIONS: Although there has been a partial decrease in mortality for PH in recent years, it is still a serious condition that requires a multidisciplinary approach and well-planned obstetric treatment.

Ocular biometry characteristics and its relationship with age, gender, spherical equivalent in Turkish children.

Background: Studying ocular biometric parameters in different populations and determining the relationship with personal characteristics can provide valuable information about ocular growth and help provide a better understanding of refractive errors. Aims: To describe distributions of ocular biometry and to evaluate its associations with age, gender, spheric equivalent in Turkish children. Patients and Methods: In this prospective study 344 children aged 3-14 years were evaluated. Parameters studied included axial length (AL), anterior chamber depth (ACD), and mean corneal radius (CR) measured with optical biometry. Cycloplegic refraction values were obtained using autorefractometer. The change of biometric parameters according to age and gender were evaluated. The relationship between ocular biometry parameters with refraction and age was analyzed by linear regression. Results: Mean spherical equivalent (SE), AL, ACD and AL/CR observed to be lowest in the preschooler group (P < 0.001). SE reduced with age, and a weak correlation observed between SE and age (r = -0.333). AL and ACD had moderate and weak positive correlations with age respectively (r = 0.511; r = 0.304). There were negative correlations between SE with AL, ACD and AL/CR (r = -0.826; r = -0.540; r = -0.886). The strongest correlation with SE among these parameters was identified for AL/CR. AL and ACD were higher in boys, while the CR was lower in girls (p < 0.001). Conclusion: While AL in children in late schooler group is higher than European countries, it shows similar characteristics in early schooler group. In addition AL is lower in all age groups than Asian population sexcept preschooler group. With age AL increases, SE decreases and AL plays a key role in refractive development.

Assessment of the orbital structures using computed tomography in healthy adults.

OBJECTIVES: In this study, we retrospectively evaluated the orbital and ocular dimensions using computed tomography (CT) scans in healthy adults. MATERIALS AND METHODS: This retrospective study included 302 Turkish adult individuals aged 20-76 years (158 males and 144 females), who underwent paranasal sinus or craniofacial CT due to headache or suspicion of sinusitis, but abnormal orbital or cranial CT findings were not detected. Linear and volumetric measurements of the orbital structures were performed in the sagittal, coronal, and axial planes on CT slices. The volume was estimated in cubic centimeters using the equation of the ellipsoid method. A total of 34 parameters were measured from both eyes of each individual using 14 different anatomical landmarks and analyzed by gender and age. RESULTS: Parameter values of orbital structures in males and females are shown in millimeters or cubic centimeters. In most of the 34 parameters that we evaluated, it was seen that males had statistically significant higher mean values than females (P < 0.05). Also, there was no statistically significant difference between the measurements of right and left orbits. The correlation with age was varied according to the 34 parameters. Interestingly enough, there were no statistically significant differences between the two genders for extraocular muscles thickness (except superior muscles group thickness-SMT) and left optic nerve thickness (LOT) (p > 0.05). The mean right superior muscles group thickness was 5.35 ± 0.85 mm in the male subjects and 4.64 ± 1.10 mm in the female subjects (P < 0.001). The mean left superior muscles group thickness (LSMT) was 5.28 ± 0.88 mm in the male subjects and 4.67 ± 1.16 mm in the female subjects (P < 0.001). The mean LOT was 6.15 ± 0.97 and 5.88 ± 1.07 mm in males and females, respectively (P = 0.099). CONCLUSION: This study can be applied to the standardization of orbital morphometry in healthy adults.

Factores para predecir los resultados de la litotricia por ondas de choque en pacientes pediátricos y validación externa de un nomograma / Factors to predict shock-wave lithotripsy results in pediatric patients and external validation of a nomogram

OBJETIVO: Evaluar la exactitud del nomograma de Dogan para predecir la tasa libre de cálculos (LC) tras una única sesión de litotricia extracorpórea por ondas de choque (LEOCH) y evaluar factores predictivos de los resultados de LEOCH en niños. PACIENTES Y MÉTODOS: En el estudio participaron 68 pacientes menores de 18 años que habían sido tratados con LEOCH en nuestro centro terciario desde enero de 2010 hasta diciembre de 2016, por cálculos radiopacos del tracto urinario superior. La media de edad fue de 50 meses (6-207) y la media del período de seguimiento, de 9 meses (4-50). Se excluyeron los pacientes con litiasis cistínica, anomalía renal, derivación urinaria y litiasis múltiples localizadas en diferentes cálices, igual que en el estudio del nomograma original. El estatus LC se evaluó mediante la realización de radiografía simple de abdomen y ecografía urinaria 2 semanas después de cada sesión de LEOCH. Los pacientes que estaban completamente libres de cálculos fueron considerados LC. Se realizaron análisis de regresión logística múltiple para determinar las variables que afectan el estado de LC. El método bootstrap con 1.000 repeticiones se utilizó para la validación externa del nomograma desarrollado por Dogan. RESULTADOS: Las tasas de LC para cada sesión de LEOCH fueron de 54,4% (37/68) para la primera sesión, de 33,3% (7/21) para la segunda y de 55,6% (5/9) para la tercera. En total, la tasa de LC fue del 72,1% (49/68). El análisis de regresión logística múltiple mostró correlaciones positivas y significativas entre la edad y el tamaño del cálculo, y el riesgo de fracaso al tratamiento con LEOCH. El gráfico de calibración externa mostró una validación aceptable respecto al nomograma de Dogan para predecir el fracaso de LEOCH en la primera sesión. CONCLUSIÓN: Nuestro estudio demostró que el nomograma de Dogan se puede utilizar para predecir el estado LC tras una sesión de LEOCH en pacientes pediátricos

OBJECTIVE: To evaluate the accuracy of the Dogan nomogram in predicting stone-free (SF) rate after a single shock wave lithotripsy (SWL) session and evaluate factors that predict SWL results in children. PATIENTS AND METHODS: The study included 68 patients under 18 years of age who had been treated with SWL for radiopaque upper urinary tract stones in our tertiary centre from January 2010 to December 2016. The median age is 50 (6-207) months and median follow-up period is 9 (4-50) months. Patients with known cystine stone disease, abnormal renal anatomy, urinary diversion and multiple stones located in different calyces were excluded like in the original nomogram study. SF status was evaluated by performing plain abdominal radiography and urinary ultrasonography 2 weeks after each SWL session. Patients who were completely free of stones were considered to be SF. Multiple logistic regression analyses were performed to determine the variables affecting SF status. The bootstrap method with 1,000 replicates was used for the external validity of a nomogram developed by Dogan. RESULTS: SF rates for each SWL session were determined as 54.4% (37/68) for the first session, 33.3% (7/21) for the second session and 55.6% (5/9) for the third session. Overall, the SF rate was 72.1% (49/68). Multiple logistic regression analysis showed positive and significant correlations of age and stone size with risk of SWL failure. The external calibration plot showed a nearly good validation with Dogan nomogram to predict SWL failure in first session. CONCLUSION: Our study demonstrates that the Dogan nomogram can be used to predict the SF status after one session of SWL in pediatric patients

Factors to predict shock-wave lithotripsy results in pediatric patients and external validation of a nomogram. / Factores para predecir los resultados de la litotricia por ondas de choque en pacientes pediátricos y validación externa de un nomograma.

OBJECTIVE: To evaluate the accuracy of the Dogan nomogram in predicting stone-free (SF) rate after a single shock wave lithotripsy (SWL) session and evaluate factors that predict SWL results in children. PATIENTS AND METHODS: The study included 68 patients under 18 years of age who had been treated with SWL for radiopaque upper urinary tract stones in our tertiary centre from January 2010 to December 2016. The median age is 50 (6-207) months and median follow-up period is 9 (4-50) months. Patients with known cystine stone disease, abnormal renal anatomy, urinary diversion and multiple stones located in different calyces were excluded like in the original nomogram study. SF status was evaluated by performing plain abdominal radiography and urinary ultrasonography 2 weeks after each SWL session. Patients who were completely free of stones were considered to be SF. Multiple logistic regression analyses were performed to determine the variables affecting SF status. The bootstrap method with 1,000 replicates was used for the external validity of a nomogram developed by Dogan. RESULTS: SF rates for each SWL session were determined as 54.4% (37/68) for the first session, 33.3% (7/21) for the second session and 55.6% (5/9) for the third session. Overall, the SF rate was 72.1% (49/68). Multiple logistic regression analysis showed positive and significant correlations of age and stone size with risk of SWL failure. The external calibration plot showed a nearly good validation with Dogan nomogram to predict SWL failure in first session. CONCLUSION: Our study demonstrates that the Dogan nomogram can be used to predict the SF status after one session of SWL in pediatric patients.

MRI Predictors of Recurrence and Outcome after Acute Transverse Myelitis of Unidentified Etiology.

BACKGROUND AND PURPOSE: The early prediction of recurrence after an initial event of transverse myelitis helps to guide preventive treatment and optimize outcomes. Our aim was to identify MR imaging findings predictive of relapse and poor outcome in patients with acute transverse myelitis of unidentified etiology. MATERIALS AND METHODS: Spinal MRIs of 77 patients (mean age, 36.3 ± 20 years) diagnosed with acute transverse myelitis were evaluated retrospectively. Only the patients for whom an underlying cause of myelitis could not be identified within 3 months of symptom onset were included. Initial spinal MR images of patients were examined in terms of lesion extent, location and distribution, brain stem extension, cord expansion, T1 signal, contrast enhancement, and the presence of bright spotty lesions and the owl's eyes sign. The relapse rates and Kurtzke Expanded Disability Status Scale scores at least 1 year (range, 1-14 years) after a myelitis attack were also recorded. Associations of MR imaging findings with clinical variables were studied with univariate associations and binary log-linear regression. Differences were considered significant for P values < .05. RESULTS: Twenty-seven patients (35.1%) eventually developed recurrent disease. Binary logistic regression revealed 3 main significant predictors of recurrence: cord expansion (OR, 5.30; 95% CI, 1.33-21.11), contrast enhancement (OR, 5.05; 95% CI, 1.25-20.34), and bright spotty lesions (OR, 3.63; 95% CI, 1.06-12.43). None of the imaging variables showed significant correlation with the disability scores. CONCLUSIONS: Cord expansion, contrast enhancement, and the presence of bright spotty lesions could be used as early MR imaging predictors of relapse in patients with acute transverse myelitis of unidentified etiology. Collaborative studies with a larger number of patients are required to validate these findings.

Medial olivocochlear suppression in musicians versus non-musicians.

The medial olivocochlear efferent (MOCE) branch synapses with outer hair cells (OHCs), and the efferent pathway can be activated via a contralateral acoustic stimulus (CAS). The activation of MOCE can change OHC motile responses and convert signals that are capable of controlling the sensitivity of the peripheral hearing system in a frequency-specific manner. The aim of this study was to examine the MOCE system activity in professional musicians using transient evoked otoacoustic emission test and CAS. Musician group showed stronger suppression in all frequency bands in the presence of CAS.

Brain MRI Findings in Pediatric-Onset Neuromyelitis Optica Spectrum Disorder: Challenges in Differentiation from Acute Disseminated Encephalomyelitis.

BACKGROUND AND PURPOSE: Differentiating pediatric-onset neuromyelitis optica spectrum disorder from acute disseminated encephalomyelitis could be challenging, especially in cases presenting with only brain manifestations. Our purpose was to investigate brain MR imaging features that may help distinguish these 2 entities. MATERIALS AND METHODS: We retrospectively examined initial brain MR imaging studies of 10 patients with pediatric-onset neuromyelitis optica spectrum disorder (female/male ratio, 7:3) and 10 patients with acute disseminated encephalomyelitis (female/male ratio, 2:8). The mean age of the patients was 10.3 ± 5.6 and 8.7 ± 5.3 years, respectively. Brain lesions were evaluated with respect to location, extent, expansion, T1 hypointensity, contrast enhancement/pattern, and diffusion characteristics. The χ2 test (Yates or Fisher exact χ2tests) was used to compare differences between groups. RESULTS: Cerebral subcortical ± juxtacortical and pons ± middle cerebellar peduncle were the most frequent locations involved in both neuromyelitis optica spectrum disorder (n = 5 and 4, respectively) and acute disseminated encephalomyelitis (n = 9 and 7, respectively). Thalamic lesions were more frequent in acute disseminated encephalomyelitis (P = .020) and were detected only in 1 patient with neuromyelitis optica spectrum disorder. None of the patients with neuromyelitis optica spectrum disorder had hypothalamic, internal capsule, or cortical lesions. The internal capsule involvement was found to be significantly different between groups (P = .033). There was no significant difference in terms of extent, expansion, T1 hypointensity, contrast enhancement/pattern, and diffusion characteristics. CONCLUSIONS: Although there is a considerable overlap in brain MR imaging findings, thalamic and internal capsule involvement could be used to differentiate pediatric-onset neuromyelitis optica spectrum disorder from acute disseminated encephalomyelitis.

Brachial Plexus Ultrasound and MRI in Children with Brachial Plexus Birth Injury.

BACKGROUND AND PURPOSE: Brachial plexus birth injury is caused by traction on the neck during delivery and results in flaccid palsy of an upper extremity commonly involving C5-C6 nerve roots. MR imaging and MR myelography help to assess the anatomic location, extent, and severity of brachial plexus injuries which influence the long-term prognosis along with the surgical decision making. Recently, sonography has been increasingly used as the imaging modality of choice for brachial plexus injuries. The aim of this study was to assess the degree of correlation among brachial plexus sonography, MR imaging, and surgical findings in children with brachial plexus birth injury. MATERIALS AND METHODS: This prospective study included 55 consecutive patients (girls/boys = 32:23; mean age, 2.1 ± 0.8 months) with brachial plexus birth injury between May 2014 and April 2017. The patients were classified according to the Narakas classification and were followed up at 4- to 6-week intervals for recovery by the Modified Mallet system and sonography without specific preparation for evaluation. All patients had MR imaging under general anesthesia. Nerve root avulsion-retraction, pseudomeningocele, and periscalene soft tissue were accepted brachial plexus injury findings on imaging. Interobserver agreement for MR imaging and the agreement between imaging and surgical findings were estimated using the κ statistic. The diagnostic accuracy of sonography and MR imaging was calculated on the basis of the standard reference, which was the surgical findings. RESULTS: Forty-three patients had pre- and postganglionic injury, 12 had only postganglionic injury findings, and 47% of patients underwent an operation. On sonography, no patients had preganglionic injury, but all patients had postganglionic injury findings. For postganglionic injury, the concordance rates between imaging and the surgical findings ranged from 84% to 100%, and the diagnostic accuracy of sonography and MR imaging was 89% and 100%, respectively. For preganglionic injury, the diagnostic accuracy of MR imaging was 92%. Interobserver agreement and the agreement between imaging and the surgical findings were almost perfect for postganglionic injury (κ = 0.81-1, P < .001). CONCLUSIONS: High-resolution sonography can identify and locate the postganglionic injury associated with the upper and middle trunks. The ability of sonography to evaluate pre- and the postganglionic injury associated with the lower trunk was quite limited. Sonography can be used as a complement to MR imaging; thus, the duration of the MR imaging examination and the need for sedation can be reduced by sonography.

Spontaneous otoacoustic emission recordings during contralateral pure-tone activation of medial olivocochlear reflex.

We hypothesized that cochlear frequency discrimination occurs through medial olivocochlear efferent (MOCE)-induced alterations in outer hair cell (OHC) electromotility, which is independent from basilar membrane traveling waves. After obtaining informed consent, volunteers with normal hearing (n = 10; mean age: 20.6 ± 1.2 years) and patients with unilateral deafness (n = 10; mean age: 30.2 ± 17.9 years) or bilateral deafness (n = 8; mean age: 30.7 ± 13.8 years) underwent a complete physical and audiological examination, and audiological tests including transient evoked otoacoustic emission and spontaneous otoacoustic emission (TEOAE and SOAE, respectively). SOAE recordings were performed during contralateral pure-tone stimuli at 1 and 3 kHz. SOAE recordings in the presence of contralateral pure-tone stimuli showed frequency-specific activation out of the initial frequency range of SOAE responses. Basilar membrane motion during pure-tone stimulation results from OHC activation by means of MOCE neurons rather than from a traveling wave. Eventually, frequency-specific responses obtained from SOAEs suggested that OHC electromotility may be responsible for frequency discrimination of the cochlea independently from basilar membrane motion.

Comparison of HbA1c analysers: Agilent 1100 HPLC using kits produced by Gordion Diagnostic (Turkey) with Premier Hb9210 using kits produced by Trinity Biotech (USA) in different patient groups.

BACKGROUND: The aim of this study was to compare the performance of Agilent 1100 HPLC analyser using HbA1c kits manufactured by Gordion Diagnostic (Turkey) with that of Premier Hb9210 using the original kits for the measurement of HbA1c in different patient groups. METHODS: Subjects were divided into four groups: Group 1 included 140 diabetic and non-diabetic subjects with normal urea and haemoglobin levels; Group 2 included 84 diabetic and non-diabetic subjects with high urea levels; Group 3 included 44 diabetic and non-diabetic subjects with iron deficiency anaemia; and Group 4 included 52 diabetic and non-diabetic subjects with high haemoglobin levels. EP Evaluator Release 8 program was used to evaluate the resultant data. RESULTS: According to the comparison results of the two methods in all groups, there was an excellent correlation between the two methods (R>0.98). Moderate-low correlation was found between increased urea concentration and the difference of the two methods (R= -0.374, p = 0.0005). The difference between the methods was found to be increased with increased urea concentrations. This difference, although statistically significant, was within the permitted limits. The observed correlation between the difference of the two methods and the low and high haemoglobin concentrations was statistically non-significant (R = 0.149, p = 0.3343; R = 0.263, p = 0.0594). CONCLUSIONS: We found that Agilent 1100 HbA1c analyser and Gordions' HbA1c kit comply with the clinical requirements and are suitable for HbA1c analysis at high levels of urea and Hb and low levels of Hb in diabetic and non-diabetic patients.

Analyses of 1100 supernumerary teeth in a nonsyndromic Turkish population: A retrospective multicenter study.

PURPOSE: The aim of this study was to analyze the clinical and radiological features of supernumerary teeth (ST), record the related complications, and discuss different forms of treatment. MATERIALS AND METHODS: A total of 111,293 patients were examined over a 3-year period. The patients' ages and genders, in addition to the number, morphology, location, position, shape, developmental stage, and eruption status of ST and associated complications, were recorded. RESULTS: Among the 111,293 patients, there were 851 (0.76%) patients with 1100 ST. Of these patients, 478 (56.2%) were males, and 373 (43.8%) were females, with a mean age of 22.71. Most of the 1100 ST were located in the maxilla, 437 (39.72%) were a conical shape, with 82.81% of these including a fully developed tooth. A mesiodens was the most common type of supernumerary tooth (n=284, 33.37%), followed by distomolars (n=204, 23.97%) and parapremolars (n=146, 17.16%). Among the 1100 ST, 422 (38.36%) were associated with complications. CONCLUSIONS: No previous studies in the literature have examined in detail so many cases with ST. The demographic profile of the patients with ST presented herein provides useful additional epidemiological information.

Assessment of the biocompatibility of mineral trioxide aggregate, bioaggregate, and biodentine in the subcutaneous tissue of rats.

OBJECTIVE: The objective of this study was to evaluate the tissue inflammation caused by three endodontic repair materials. MATERIALS AND METHODS: The materials included micro mega-mineral trioxide aggregate (MM-MTA), bioaggregate (BA), and biodentine (BD), which were implanted into the subcutaneous tissue of rats. The tissue samples for histological examination were prepared. The infiltration of lymphocytes and macrophages into the tissue was examined to assess the inflammatory response. RESULTS: Lymphocyte infiltration: A significant increase was detected in the MM-MTA and BA groups on the 7th and 14th days as compared with the control (7th day P=0.0001, 14th day P=0.0176). There was no difference between the groups on the 45th day (P=0.1730). Lymphocyte infiltration had decreased over time in all groups. Macrophage infiltration: There was a significant increase by the 7th day in the test groups as compared to the control group (P=0.007). However, there was no difference between the experimental groups on the 14th (P=0.2708) and 45th (P=0.1291) days. CONCLUSION: While MM-MTA and BA showed a similar biocompatibility, BD was more biocompatible than MM-MTA and BA in the 1 st week of the experiment. However, there was no difference between the materials at the end of the 45th day. MM-MTA, BA, and BD can be considered suitable endodontic repair materials.

Complex and compound odontomas: Analysis of 69 cases and a rare case of erupted compound odontoma.

OBJECTIVE: The purpose of this study was to analyze clinic and radiologic features of the 69 odontoma cases and present a rare case of erupted compound odontoma in the oral cavity. MATERIAL AND METHODS: The 69 cases were analyzed with regard to the following parameters: age, gender, location, associated unerupted teeth, missing teeth, radiological and histopathological features and treatment protocols. RESULTS: Of the 69 cases, 49 were compound odontoma and 20 were complex odontoma. There was a female predilection for both compound and complex odontomas. Compound odontoma occurred more often in the anterior region of the jaws; complex lesions occurred more often at the posterior mandible. The most common clinical manifestations were the retention of permanent teeth. CONCLUSION: Compound odontomas rarely erupt into the mouth. The presented case is the 13 th case of erupted compound odontoma reported in the literature. The treatment of choice is surgical removal of the odontoma. In the case of odontomas associated to impacted teeth, the teeth should be preserved in wait of spontaneous eruption, or alternatively fenestration followed by orthodontic traction is indicated. Regular follow-up period is crucial to evaluate the prognosis of these teeth.

Efficacy of Ankaferd Blood Stopper on bone healing in diabetic rats: a stereological and histopathological study.

We evaluated the effects of Ankaferd Blood Stopper (ABS) and routine antibiotic prophylaxis (AP) on early healing of bone defects in diabetic rats. We used 48 rats in the study. Diabetes was induced in 24 rats using streptozotocin; the remaining 24 healthy untreated rats served as controls. Twelve of the diabetic rats and 12 of the healthy rats were treated with AP for 3 days before surgery. Bilateral bone defects were created in the mandible of all animals. ABS was applied to the defects on the left sides of the mandibles, while nothing was applied to the right sides. Animals were sacrificed on days 7 and 14 after operation and examined for histopathology and by stereology. The volume of newly formed bone was significantly less in the diabetic rats on both days 7 and 14. Local administration of ABS significantly increased the mean volume of newly formed bone in both diabetic and nondiabetic rats at days 7 and 14. No significant difference in new bone formation was found between AP and ABS treatment in diabetic rats. Both AP and local administration of ABS have beneficial effects on bone healing in diabetic animals.

Shear bond strength of orthodontic attachments bonded to impacted teeth under in vivo and in vitro conditions.

OBJECTIVES: To evaluate and compare the shear bond strength (SBS) of stainless steel and gold-plated attachments to impacted lower third molars in vivo and in vitro with a light-cured orthodontic resin. SETTING AND SAMPLE POPULATION: Sixteen patients with bilaterally full soft tissue impaction of lower third molars were recruited on a voluntary basis from an oral and maxillofacial surgery department. MATERIALS AND METHODS: A split-arch technique was used. Following surgical exposure of the crown, the tooth was luxated but not extracted. Then, two attachments (one stainless steel button and one gold-plated eyelet) were bonded to the labial enamel surface of the loosened tooth. Five minutes later, the luxated tooth was removed from its socket. In each patient, the impacted tooth on the other side was extracted, and attachments were bonded in vitro. The SBSs of the attachments were evaluated. For comparison, analysis of variance and multiple range tests were used (α = 0.05). RESULTS: Statistically significant differences were evident in attachment adhesion to the impacted tooth surfaces among the four groups (p < 0.001). Superior SBS values were obtained for stainless steel button groups bonded in vitro. The mean bond strengths of the groups bonded in vitro were better than those of the same groups bonded in vivo. CONCLUSIONS: Although the in vitro-bonded groups showed higher SBS values, adequate bond strength is possible with stainless steel buttons bonded in vivo.