Comparison of Cone-beam Computed Tomography and Multi-slice Spiral Computed Tomography Bone Density Measurements in the Maxilla and Mandible.

UNLABELLED: The purpose of this study was to compare cone-beam computer tomography (CBCT) and multi-slice spiral computed tomography (MSCT) bone density measurements in the maxilla and mandible to determine whether any discrepancies between imaging modalities exist. MATERIAL & METHODS: 33 sets of CBCT and MSCT scans were evaluated using Simplant software. Density measurements were made in eight regions of interest on each scan and were compared and analyzed. RESULTS: Correlation of density measurements at specific regions of interest between CBCT and MSCT was only fair and ranged from 0.61-0.86. High-density areas, such as the anterior mandible, showed a higher correlation between imaging modalities than low-density regions, such as the posterior maxilla. CONCLUSION: Care should be taken when relying upon CBCT to determine bone density, especially in low-density regions such as the posterior maxilla.

Surgical management of the buccal bifurcation cyst: bone grafting as a treatment adjunct to enucleation and curettage.

The buccal bifurcation cyst (BBC) is a rare inflammatory odontogenic cyst of unknown etiology. It typically develops on the buccal aspect of the permanent mandibular first molar and occasionally on the permanent mandibular second molar in children 4 to 14 years old. Distinct clinical findings of the BBC include involvement of a vital partially or fully erupted mandibular first or second molar, swelling in the affected mandibular molar region, delayed or altered eruption pattern of the involved tooth, and an increase in periodontal pocket depth when the affected tooth is partially erupted. Specific radiographic features include a radiolucent lesion on the buccal aspect of the tooth involving the roots to a variable extent, tilting of the involved molar so that the root apices are toward the lingual cortical plate, an intact periodontal ligament space and lamina dura, a periosteal reaction on the buccal surface, and an intact inferior border of the mandible. The histopathology of the lesion has been described as similar to a radicular or inflammatory odontogenic cyst. Most of the current literature supports simple enucleation and curettage of the cyst without extraction of the involved tooth as the treatment of choice. This report presents 3 cases of BBCs that were treated with enucleation and curettage without extraction of the involved tooth, in addition to a bone graft placed primarily or secondarily as an adjunctive treatment approach to the current therapies.

Correlation between Schneiderian membrane perforation and sinus lift graft outcome: a retrospective evaluation of 359 augmented sinus.

PURPOSE: The aim of this study was to estimate the incidence of sinus membrane perforation in maxillary sinus augmentation surgery using a lateral approach and the impact of sinus integrity on incidence of sinusitis and bone graft survival in the maxillary sinus. PATIENTS AND METHODS: A total of 359 sinus augmentation procedures (208 patients) were evaluated retrospectively for sinus integrity during augmentation, complications, graft failure, and implant loss. RESULTS: The incidence of sinus membrane perforation was 41%. There was an overall sinus graft failure rate of 6.7%; of the failed sinus grafts, 70.8% had a perforated sinus membrane at augmentation. There were 11.3% of sinuses with perforated membranes at graft placement that failed compared with 3.4% of sinuses with intact membranes failing (general linear model [GLM], P = .003). Age, gender, and provider type were not significantly associated with sinus integrity at 1 year. Overall, 11.3% of sinuses with perforated membranes at graft placement required secondary antibiotics for sinusitis and infection compared with 1.4% of sinuses with intact membranes (GLM, P < .0006). Of the sinuses requiring secondary antibiotics, 30% failed compared with 5% of untreated sinuses (GLM, P = .0071). Of the sinuses developing sinusitis or secondary infection requiring antibiotics, 85% had a membrane perforation during augmentation compared with 39.2% of those not requiring antibiotics; gender, age, and provider were not associated with antibiotic use. CONCLUSIONS: In the present study, antibiotic use for postoperative sinusitis and infection and graft failure were shown to be statistically higher in sinuses with perforated membranes at augmentation.

Cavernous sinus thrombosis as a result of a fungal infection: a case report.

Cavernous sinus thrombosis (CST) is a rare disease with the potential for significant morbidity and even death. Rapid diagnosis and aggressive medical and surgical management are imperative for patients with CST. The cause may be aseptic or infectious. When the cause is infectious in nature, it is most commonly from a bacterial origin. However, we present the case of a 57-year-old man with a fungally related CST that ultimately led to his death.

Management of central giant granuloma of mandible with intralesional triamcinolone injections: a case report.

A 31-year-old female presented with a central giant cell granuloma of the mandible. The patient was successfully treated with intralesional triamcinolone for a period of six weeks. At a two-year follow-up, the patient showed no clinical or radiographic signs of the lesion.

Correlation between insertion torque and survival rates in immediately loaded implants in the maxilla: a retrospective study.

OBJECTIVE: To evaluate the correlation between insertion torque and the survival rate of immediately loaded implants placed in the maxilla. METHODS: 390 NobelReplace (Nobel Biocare USA, Yorba Linda, CA) Select Tapered implants were placed in the maxillae of 145 patients over a 15-month period. The insertion torque was measured using a digital torque wrench. RESULTS: Of the 390 implants, only 9 (2.3%) failed. The 381 successful implants were placed with an average insertion torque of 72.1 N.cm. Insertion torque values of failed implants varied between 45.8 and 134 N.cm, with an average of 69.2 N.cm. Of the 9 failed implants, 8 were abutments in multiple-unit implant-supported prostheses, and 1 was a single-unit implant. CONCLUSIONS: Although insertion torque undoubtedly plays an important role in the primary stability and successful osseointegration of implants, there seems to be no correlation between insertion torque and implant failure above 35 N.cm threshold of insertion torque. Immediate loading of implants in the maxilla is a successful and predictable treatment option with failure rates approaching those of traditional 2-stage surgery.

Augmentation of the anterior maxilla with intraoral onlay grafts for implant placement.

The use of autogenous cortical cancellous block grafts to augment the premaxilla is a safe and effective technique to provide adequate bone height and width when reconstructing patients with atrophic premaxilla ridge when endosteal implants are planned. Intraoral bone graft harvests have the advantages of proximity of the donor site to the graft site, convenient surgical access, minimal operative time, and ease of performance in an office setting. The major limitation of these donor sites is the smaller quantity of graft obtainable compared with iliac crest bone harvest sites.

Effect of sinus membrane perforation on dental implant integration: a retrospective study on 128 patients.

A common complication of sinus augmentation is perforation of the sinus membrane during augmentation and/or implant placement. This retrospective study examines the effect of sinus membrane perforation with regard to graft survival and implant integration. A total of 175 sinuses were augmented with 115 of the membranes being reported intact at the time of surgery. A total of three infections occurred in patients who sustained perforated sinuses and one infection occurred in a patient who had an intact sinus. All four infections resolved after culture sensitivity and placement of the patient on an appropriate antibiotic for 10 days. Of 438 dental implants placed in the augmented sinuses, five implants failed, four of which were associated with perforated sinuses and and which was not associated with a perforated grafted sinus.

Immediate loading of dental implants in the anterior and posterior mandible: a retrospective study of 120 cases.

PURPOSE: The objective of this retrospective study was to evaluate the overall success of immediately loaded implants in the mandible. This report focuses on immediately loaded anterior and posterior mandibular implants. MATERIALS AND METHODS: A total of 979 patients received 2,904 mandibular dental implants placed from January 2007 to December 2008. One hundred sixty-one of the implants were placed anterior to the mental foramen, and 95 were placed posterior to the mental foramen. All immediately loaded implants were torque tested to 35 N-cm. All were provisionally restored the day of insertion. RESULTS: A total of 256 immediately loaded mandibular dental implants were placed in a 2-year period. Of the 256 immediately loaded implants, 252 integrated and were restored and 4 failed. Of the 4 failed implants, 3 were in the anterior mandible and the fourth was in the posterior mandible. All 4 were replaced, integrated, and have been restored. The survival rate for immediately loaded implants in the anterior mandible was 99.4%, and the survival rate in the posterior mandible was 97%. CONCLUSION: Immediately loaded implants have predictable clinical success in the anterior and posterior mandible.

Off-label use of rhBMP-2 for reconstruction of critical-sized mandibular defects.

Techniques for reconstructing segmental defects of the mandible have traditionally relied upon autogenous tissue transfer. Tissue engineering has brought about the promise of de novo bone formation and the possibility of reconstruction of these defects without the drawbacks of traditional techniques. Bone morphogenic proteins (BMP) have presented themselves as the most promising in this field. We present three cases where reconstruction of critical-sized mandibular defects was attempted using recombinant human BMP-2.

Use of tilted implants in treatment of the atrophic posterior mandible: a preliminary report of a novel approach.

PURPOSE: Restoration of the atrophic partially edentulous posterior mandible with implant retained prostheses has proved to be problematic, with no ideal treatment modality. The purpose of this report is to offer a novel method of treatment using tilted endosseous implants. MATERIALS AND METHODS: A total of 64 patients with edentulous spans of the mandible and less than 9.5 mm of alveolar bone overlying the inferior alveolar nerve had implants placed. The implants were placed in a bicortical manner with the porous hydroxyapatite placed subperiosteally if more than 1 mm of the apex of the implant was placed beyond the lingual cortex of the mandible. These implants were allowed to osseointegrate for 3 to 5 months and restored using custom-angled abutments. RESULTS: A total of 196 implants were placed in 64 patients from March 2003 through July 2008. Two implants were lost owing to a lack of osseointegration. No implants were lost because of prosthodontic failure. No damage to the neurovascular structures or permanent paresthesia was noted. CONCLUSIONS: Our initial results have shown that the use of tilted implants combined with custom abutments is a viable treatment modality for patients with atrophic edentulous mandibular spans that lack the required alveolar height for traditional dental implants.

Root and pulp response after intentional injury from miniscrew placement.

INTRODUCTION: The purpose of this study was to evaluate the effects on the pulp and supporting tissues when miniscrews severely abrade the root surface. METHODS: Sixty self-drilling and self-tapping miniscrews were placed between the premolars and molars of 3 beagles (20 miniscrews per dog). The miniscrews were placed according to the protocol suggested by the manufacturer, but with the intention of inflicting root damage. Radiographs were taken of all 60 interdental alveolar sites, 5 in each quadrant, and sites that evidenced root proximity were identified. The animals were killed at 12 weeks, and 20 of the most probable injury sites were selected for histologic analysis. Serial nondecalcified sections and microcomputed tomography scans were obtained with the implants in place. RESULTS: There was no histologic evidence of inflammatory response either at the root surface or in the pulp. Pulp necrosis, external resorption, and ankylosis were not found, but reparative cementum was seen at each injury site. The presence of woven bone along miniscrew threads lends evidence to support the osseointegration of miniscrews. CONCLUSIONS: Permanent damage to the pulp and supporting tissues is not a regular occurrence when miniscrews abrade or even enter the root surface.

Cementum, pulp, periodontal ligament, and bone response after direct injury with orthodontic anchorage screws: a histomorphologic study in an animal model.

PURPOSE: To assess the histologic response of the periodontium, cementum, and pulp after intentional root injury with titanium screws. MATERIALS AND METHODS: Three female beagle dogs were used, and a total of 60 self-drilling/self-tapping miniscrews were manually inserted into the maxilla and the mandible with the intention of placement in close proximity or in direct contact with the roots. Digital radiographs were taken to select the sites with root injuries. After a 3-month period, the animals were killed and serial nondecalcified histologic sections were obtained with the miniscrew in place. RESULTS: Sixteen sites with significant root injury were identified. Four sites presented with cementum abrasion, 7 sites had dentin penetration up to 50% of the diameter of the screw, and 5 sites had miniscrew penetration into the pulp space with root fragmentation. At all damaged sites, continuous cementum repair could be observed. There was no evidence of external resorption or pulpal necrosis and/or inflammatory infiltrate. Point ankylosis was seen only in cases of severe injury with root fragmentation. Finally, woven bone was present along the miniscrew threads. CONCLUSION: When titanium screws penetrate root cementum or dentin, pulpal necrosis and/or inflammation was not observed at 12 weeks in an animal model. Cementum regenerates at every injury site, but ankylosis can occur with root fragmentation. Woven bone is present at the screw-bone interface even with root contact suggesting osteointegration.

Outcomes of placing short dental implants in the posterior mandible: a retrospective study of 124 cases.

PURPOSE: The purpose of this retrospective study was to determine the overall success of short dental implants (8 mm in length) placed in the partially or completely edentulous posterior mandible restored with fixed and removable prostheses. PATIENTS AND METHODS: A total of 124 patients had 335 8-mm-long implants placed from May 2005 until June 2007. Of the 124 total patients, 35 were men and 89 were women, with a median age of 56 years and an age range of 18 to 80 years at the time of implant surgery. There were 112 patients who were partially edentulous and 12 who were completely edentulous. Of the patients, 32 had a single implant placed whereas the other 92 had multiple implants placed. One patient had the implants immediately provisionally loaded. All of the implants were restored by use of fixed prostheses. Of these fixed prostheses, 245 were splinted together whereas 75 were restored individually. RESULTS: A total of 335 short dental implants were placed in 124 patients. Of the 335 implants placed, 331 integrated successfully. In the 2 cases that failed, the sites were grafted with porous hydroxyapatite and platelet-rich plasma. The implants were replaced at 5 months after the initial failure in the first patient and at 7 months in the second patient. These replacement implants integrated and have been restored and in function for more than 16 months. There was 1 fracture of an implant with a restoration. The implant had been restored with an individually fabricated fixed restoration, with the fracture occurring at the head of the implant, requiring removal. The implant and restoration had been in function for 10 months before fracture.There were no other fractures of implants or restorative hardware noted in this study. The survival rate for 8-mm implants placed in the mandible was 99% from stage I surgery to a functional prosthesis for up to 2 years. CONCLUSIONS: Placement of short dental implants is a predictable treatment method for patients with decreased posterior mandibular bone height.