Retrospective Clinical Study of 988 Dual Acid-Etched Implants Placed in Grafted and Native Bone for Single-Tooth Replacement

Purpose: To evaluate the influence of sex, implant characteristics, and bone grafting on the survival rate of dual acid-etched (DAE) implants. Materials and Methods: Patients treated with internal-hex DAE implants for single-tooth replacement in a military dental clinic between January 2005 and December 2010 were included in this study. Clinical data related to implant characteristics, implant location, presence of grafted bone, and implant failures were collected. The primary outcome was implant loss. The survival rate was analyzed using the Kaplan-Meier method. Cox regression modeling was used to determine which factors would predict implant failure. Results: DAE implants were evaluated in a total of 988 patients (80.3% men). Twenty-four (2.4%) implants failed, most were cylindric (54.2%) with regular platforms (70.8%) and were 10 mm long (58.3%). The failure rate was 2.4% for the anterior maxilla, 3.3% for the posterior maxilla, 1.6% for the anterior mandible, and 2.0% for posterior mandible. The cumulative survival rate was 97.6%. The failure rate was 8.8% in implants placed after sinus augmentation, 7.3% in bone block-grafted areas, and 1.6% in native bone. Based on multivariable analysis (Cox regression), sinus augmentation and bone block grafting had a statistically significant effect on implant failure; the hazard ratios were 5.5 and 4.6, respectively. Conclusion: The results revealed that DAE implants had high survival rates, and no influence of sex, location, shape, diameter, or length on failure rates could be observed. However, a significant association was observed between failure and presence of bone graft in the implant area. Int J Oral Maxillofac Implants 2012;27:1243-1248

Central Granular Cell Odontogenic Tumor of the Maxilla

The central granular cell odontogenic tumor (CGCOT) is a rare benign odontogenic neoplasm composed of varying amounts of large eosinophilic granular cells and apparently inactive odontogenic epithelium. It tends to occur as a small asymptomatic swelling in the posterior region of the mandible with nonaggressive appearance. We report an unusual case of CGCOT in the maxillary region with clinical features of malignancy. The patient underwent surgical treatment, and the 2-year follow-up revealed no signs of recurrence. Central granular cell odontogenic tumor is a very rare condition with few cases reported, especially in the maxillary region. This case highlights the possibility of aggressive behavior by these lesions.

Bidirectional Barbed Suture for Bladder Neck Reconstruction, Posterior Reconstruction and Vesicourethral Anastomosis During Robot Assisted Radical Prostatectomy

Background: The urethrovesical anastomosis is a particular challenging step of robot assisted radical prostatectomy (RARP). Failure to achieve a watertight anastomosis is associated with postoperative urinary leak and its consequences, which include paralytic ileus, prolonged catheterization, urinary peritonitis and possibly re-intervention. The bidirectional barbed suture is a new technology that may lead to improve the quality of the urethrovesical anastomosis. Objective: To present our surgical technique of urethrovesical anastomosis, bladder neck reconstruction and posterior reconstruction, using a bidirectional barbed suture. Material and methods: The bladder neck reconstruction, posterior reconstruction and vesicourethral anastomosis were performed using a 2-0 synthetic absorbable bidirectional monofilament barbed suture Results: All cases were finished successfully without major complication or conversion to laparoscopic or open surgery. Conclusion: The authors successfully modified their RARP technique to take advantage of the properties of the bidirectional barbed suture. Comparative studies that evaluate objective outcomes such as leakage rates and operative time are needed to definitely establish the benefits of this device in comparison to the traditional absorbable monofilament. (C) 2011 AEU. Published by Elsevier Espana, S.L. All rights reserved.

Conservative Management of a Large Keratocystic Odontogenic Tumor in the Maxilla

Keratocystic odontogenic tumor is characterized by high recurrence rates. Conservative or aggressive management has been suggested as a method of treatment. Decompression is a conservative treatment that has been used in the treatment of large odontogenic cysts. The authors report a case of a 14-year-old patient with a keratocystic odontogenic tumor located in the right maxilla, which was treated by decompression followed by enucleation with curettage. The lesion did not recur on follow-up for 3 years after the enucleation surgery.

Influence of pulp condition on the accuracy of an electronic foramen locator in posterior teeth: an in vivo study

The aim of this study was to assess, in vivo, the accuracy of the NovApex (R) electronic foramen locator in determining working length (WL) in vital and necrotic posterior teeth. The NovApex (R) was used in 144 canals: 35 teeth with vital pulps (68 canals) and 42 teeth with necrotic pulps (76 canals). WL was measured with the NovApex (R) locator and confirmed using the radiographic method. Differences between electronic and radiographic measurements ranging between 0.0 and 0.4 millimeters were classified as acceptable; differences equal to or greater than 0.5 millimeter were considered unacceptable. Pearson's chi-square test was used to assess the influence of pulp condition on the accuracy of NovApex (R) (alpha = 0.05). Regardless of pulp condition, differences between electronic and radiographic WL measurements were acceptable in 73.61% of the canals. No statistically significant differences in accuracy were observed when comparing vital and necrotic canals (p > 0.05). There were 38 unacceptable measurements. In none of these cases was the file tip located beyond the radiographic apex; in 32, it was located short of the NovApex (R) measurement. Pulp condition had no significant effect on the accuracy of NovApex (R).

Soft tissue profile changes after rapid maxillary expansion with a bonded expander

The aim of this study was to evaluate the short-and long-term treatment effects of rapid maxillary expansion (RME) on the soft tissue facial profile of subjects treated with a modified acrylic-hyrax device. The sample comprised 10 males and 10 females in the mixed dentition. Their average age was 9.3 years +/- 10 months pre-treatment (T1), with a narrow maxilla and posterior crossbite, treated with a modified fixed maxillary expander with an occlusal splint. Lateral cephalometric radiographs obtained at T1, immediately post-expansion (T2), and after retention (T3) were used to determine possible changes in the soft tissue facial profile. The means and standard deviations for linear and angular cephalometric measurements were analysed statistically using analysis of variance and Tukey's test (alpha = 0.05). The measurements at T2 differed significantly from those at T1 and T3. However, RME did not produce any statistically significant alteration (P > 0.05) in the soft tissue profile for any of the cephalometric landmarks evaluated when compared at T1 and T3. The use of a fixed expander associated with an occlusal splint did not cause significant alterations in the soft tissue facial profile at T3. This modified device is effective for preventing the adverse vertical effects of RME such as an increase anterior face height in patients with a crossbite.

Maxillary sinus and posterior teeth: accessing close relationship by cone-beam computed tomographic scanning in a brazilian population

Introduction: This study aimed to evaluate the close proximity established between the maxillary sinus floor and posterior teeth roots apices by using cone-beam computed tomographic scanning. Methods: The relationship of maxillary sinuses and posterior teeth roots, which were divided into 2 groups, was analyzed using i-CAT Vision software (Imaging Sciences, Hatfield, PA). Group 1 included all root apices found in close contact with the maxillary sinus floor without sinus floor elevation, whereas group 2 included all root apices that were protruded within the sinus producing an elevation of the bony cortical. Results: A total of 100 maxillary sinuses and 601 roots apices were evaluated. Group 1 presented 130 of 601 (21.6%) roots and group 2 presented 86 of 601 (14.3%) roots. Conclusions: The second molar mesiobuccal root apex is frequently found in close proximity with the sinus floor, and the relation between these anatomic structures should be considered in order to prevent an iatrogenic procedure and minimize the risks from an infectious disease within the sinus

Comparative analysis of the anterior and posterior length and deflection angle of the cranial base, in individuals with facial pattern I, II and III

Objective: This study evaluated the variations in the anterior cranial base (S-N), posterior cranial base (S-Ba) and deflection of the cranial base (SNBa) among three different facial patterns (Pattern I, II and III). Method: A sample of 60 lateral cephalometric radiographs of Brazilian Caucasian patients, both genders, between 8 and 17 years of age was selected. The sample was divided into 3 groups (Pattern I, II and III) of 20 individuals each. The inclusion criteria for each group were the ANB angle, Wits appraisal and the facial profile angle (G’.Sn.Pg’). To compare the mean values obtained from (SNBa, S-N, S-Ba) each group measures, the ANOVA test and Scheffé’s Post-Hoc test were applied. Results and Conclusions: There was no statistically significant difference for the deflection angle of the cranial base among the different facial patterns (Patterns I, II and III). There was no significant difference for the measures of the anterior and posterior cranial base between the facial Patterns I and II. The mean values for S-Ba were lower in facial Pattern III with statistically significant difference. The mean values of S-N in the facial Pattern III were also reduced, but without showing statistically significant difference. This trend of lower values in the cranial base measurements would explain the maxillary deficiency and/or mandibular prognathism features that characterize the facial Pattern III.

Panic-like defensive behavior but not fear-induced antinociception is differently organized by dorsomedial and posterior hypothalamic nuclei of Rattus norvegicus (Rodentia, Muridae)

The hypothalamus is a forebrain structure critically involved in the organization of defensive responses to aversive stimuli. Gamma-aminobutyric acid (GABA)ergic dysfunction in dorsomedial and posterior hypothalamic nuclei is implicated in the origin of panic-like defensive behavior, as well as in pain modulation. The present study was conducted to test the difference between these two hypothalamic nuclei regarding defensive and antinociceptive mechanisms. Thus, the GABA A antagonist bicuculline (40 ng/0.2 µL) or saline (0.9% NaCl) was microinjected into the dorsomedial or posterior hypothalamus in independent groups. Innate fear-induced responses characterized by defensive attention, defensive immobility and elaborate escape behavior were evoked by hypothalamic blockade of GABA A receptors. Fear-induced defensive behavior organized by the posterior hypothalamus was more intense than that organized by dorsomedial hypothalamic nuclei. Escape behavior elicited by GABA A receptor blockade in both the dorsomedial and posterior hypothalamus was followed by an increase in nociceptive threshold. Interestingly, there was no difference in the intensity or in the duration of fear-induced antinociception shown by each hypothalamic division presently investigated. The present study showed that GABAergic dysfunction in nuclei of both the dorsomedial and posterior hypothalamus elicit panic attack-like defensive responses followed by fear-induced antinociception, although the innate fear-induced behavior originates differently in the posterior hypothalamus in comparison to the activity of medial hypothalamic subdivisions.

Effects of active and passive lacebacks on antero-posterior position of maxillary first molars and central incisors

The purpose of this study was to compare the effects of active and passive lacebacks on antero-posterior position of maxillary first molars and central incisors during leveling phase. Twenty-three subjects with Class I and Class II malocclusion were treated with first premolars extraction using preadjusted appliances (MBT 0.022-inch brackets). The leveling phase was performed with stainless steel archwires only. The sample was divided into 2 groups: 14 subjects received active lacebacks (Group 1) and 9 subjects received passive lacebacks (Group 2). Lacebacks were made from 0.008-inch ligature wire. Lateral cephalometric radiographs were taken pre- and post-leveling phase. Student's t-test was applied to determine the differences between pre- and post-leveling mean values and to determine the mean differences between groups. In Group I, the first molars showed a significant mesial movement, whereas no change was observed in Group 2. In both groups, maxillary central incisor crowns moved to lingual side. In conclusion, active laceback produced anchorage loss of maxillary first molars whereas passive laceback did not affect the position of these teeth. Active and passive lacebacks were effective in preventing central incisor proclination.

Effect of rapid maxillary expansion on the dimension of the nasal cavity and on facial morphology assessed by acoustic rhinometry and rhinomanometry

OBJECTIVE: To assess the effects of rapid maxillary expansion on facial morphology and on nasal cavity dimensions of mouth breathing children by acoustic rhinometry and computed rhinomanometry. METHODS: Cohort; 29 mouth breathing children with posterior crossbite were evaluated. Orthodontic and otorhinolaryngologic documentation were performed at three different times, i.e., before expansion, immediately after and 90 days following expansion. RESULTS: The expansion was accompanied by an increase of the maxillary and nasal bone transversal width. However, there were no significant differences in relation to mucosal area of the nose. Acoustic rhinometry showed no difference in the minimal cross-sectional area at the level of the valve and inferior turbinate between the periods analyzed, although rhinomanometry showed a statistically significant reduction in nasal resistance right after expansion, but were similar to pre-treatment values 90 days after expansion. CONCLUSION: The maxillary expansion increased the maxilla and nasal bony area, but was inefficient to increase the nasal mucosal area, and may lessen the nasal resistance, although there was no difference in nasal geometry. Significance: Nasal bony expansion is followed by a mucosal compensation.

Width of buccal and posterior corridors: differences between cases treated with asymmetric and symmetric extractions

OBJECTIVE: To verify if there is difference in the buccal and posterior corridor width in cases treated with extraction of one and four premolars. METHODS: Through posed smile photographs of 23 Class II patients, subdivision, treated with extraction of one premolar and 25 Class I and Class II patients, subdivision, treated with extraction of four premolars, the percentage of buccal and posterior corridor width was calculated. The two protocols of extractions were compared regarding the buccal and posterior corridor width by independent t tests. RESULTS: There was no statistically significant difference on the buccal and posterior corridor widths between patients treated with symmetric and asymmetric extraction. CONCLUSION: The buccal and posterior corridor did not differ between the evaluated protocols of extractions.