Perforation Of Cortical Plate Research Articles

Squamous Odontogenic Tumor in the Posterior Region of Maxilla.

Squamous odontogenic tumor (SOT) is a rare benign but locally infiltrative tumor often misdiagnosed as other entities, such as ameloblastoma and squamous cell carcinoma, due to overlapping morphological findings. We document here the clinicopathological and imaging findings of an aggressive intraosseous SOT in the posterior left region of the maxilla in a 25-year-old male patient. On intraoral examination, the tumor extended from the region of the left lateral incisor to the upper left premolar and was covered by reddish mucosa, with discrete areas of ulceration. Imaging exams revealed an osteolytic lesion causing thinning, erosion, and buccal and lingual cortical plate perforation associated with an impacted canine. Microscopically, the tumor showed a proliferation of islands of well-differentiated squamous epithelium in a variably collagenized background. The peripheral cells of the islands were flat or slightly cuboidal and did not exhibit nuclei with peripheral palisade and reverse polarization. The diagnosis of SOT was rendered. The patient underwent surgical resection and has been under clinical follow-up for approximately 12 months with no signs of recurrence. A careful morphological evaluation is essential to avoid misdiagnosis and ensure a satisfactory treatment approach.

Evaluation of Cone-beam Computed Tomography to differentiate Odontogenic Periapical Cysts and Granulomas

Background: Cone-beam Computed Tomography is a useful diagnostic tools for the detection of odontogenic peripheral cysts and granulomas.
 Objective: The purpose of the present study was to assess the accuracy of CBCT for diagnosing periapical cyst and granuloma.
 Methodology: This cross-sectional study was conducted from February 2017 to November 2017. Following inclusion and exclusion criteria consecutive patients who were consult in the department of oral and maxillofacial surgery of Dhaka Dental College Hospital and Bangabandhu Seikh Mujib Medical University for periapical infection was selected. Only those patients showing a periapical lesion of minimum 5 mm size was included in the study subject. Intra-oral periapical radiograph showing criteria was presence of apical radiolucency of 5 mm, corticated borders and displacements of roots. The CBCT images were done for those patients. The following features were documented on CBCT like location at the apex of involved tooth, well defined corticated border, shape is curved or circular, internal structure of lesion is radiolucent, displacement and resorption of the roots of adjacent teeth with a curved outline and perforation of cortical plate. Histopathological specimens were obtained for microscopic examination. The findings of histopathological examinations were correlated with the findings of CBCT.
 Results: Out of 50 subjects, 41(82.0%) subjects were diagnosed as cyst and 9(18.0%) subjects were as granuloma. Postoperative histopathology revealed 37 out of 41 were cysts and 4 were granulomas. Out of 9 granulomas 3 were cysts and 6 were granulomas. In this study we found the PPV 90.2439 and NPV 66.66. Diagnostic Accuracy was measured by calculating TP, TN and total population. The accuracy was 86%.
 Conclusion: In conclusion Cone-beam Computed Tomography has high accuracy of CBCT for diagnosing periapical cyst and granuloma.
 Journal of National Institute of Neurosciences Bangladesh, July 2022;8(2):171-174

A short review on guided implant surgery and its efficiency.

Ideal implant placement may reduce surgical complications, such as nerve injury and lingual cortical plate perforation, and minimize the likelihood of functional and prosthetic compromises. Guided implant surgery [GIS] has been used as the means to achieve ideal implant placement. GIS refers to the process of digital planning, custom-guide fabrication, and implant placement using the custom guide and an implant system-specific guided surgery kit. GIS includes numerous additional steps beyond the initial prosthetic diagnosis, treatment planning, and fabrication of surgical guides. Substantial errors can occur at each of these individual steps and can accumulate, significantly impacting the final accuracy of the process with potentially disastrous deviations from proper implant placement. Pertinent overall strategies to reduce or eliminate these risks can be summarized as follows: complete understanding of the possible risks is fundamental; knowledge of the systems and tools used is essential; consistent verification of both diagnostic and surgical procedures after each step is crucial; proper training and surgical experience are critical. This review article summarizes information on the accuracy and efficacy of GIS, provides insight on the potential risks and problems associated with each procedural step, and offers clinically relevant recommendations to minimize or eliminate these risks.

The occurrence of dental implant malpositioning and related factors: A cross-sectional cone-beam computed tomography survey.

PurposeDental implants are widely used for the rehabilitation of edentulous sites. This study investigated the occurrence of dental implant malpositioning as shown on post-implantation cone-beam computed tomography (CBCT) and to identify related factors.Materials and MethodsSamples with at least 1 malpositioned dental implant were collected from a central radiology clinic in Tehran, Iran from January 2017 to January 2019. Variables such as demographic characteristics, length and diameter of implants, type of implant, sites of implant insertion, different types of implant malpositioning problems (cortical plate perforation, interference with anatomical structures), angulation of the implant, and the severity of malpositioning were assessed. In addition, the incidence of implant fracture and over-drilling was evaluated. Data were statistically analyzed using the chi-square test, 1-sample t-test, and Spearman correlation coefficients.ResultsIn total, 252 patients referred for implant postoperative CBCT evaluations were assessed. The cases of implant malpositioning included perforation of the buccal cortical plate (19.4%), perforation of the lingual cortical plate (14.3%), implant proximity to an adjacent implant (19.0%), implant proximity to an adjacent tooth (3.2%), interference with anatomical structures (maxillary sinus: 18.3%, mandibular canal: 11.1%, nasal cavity: 6.3%, mental foramen: 5.6%, and incisive canal: 0.4%). Implant fracture and over-drilling were found in 1.6% and 0.8% of cases, respectively. Severity was categorized as mild (9.5%), moderate (35.7%), severe (37.7%), and extreme (17.1%), and 52.4% of implants had inappropriate angulation.ConclusionCBCT imaging is recommended for detecting dental implant malpositioning. The most common and severe type of malpositioning was buccal cortex perforation.

Guided implant surgery risks and their prevention.

Ideal implant placement may reduce surgical complications, such as nerve injury and lingual cortical plate perforation, and minimize the likelihood of functional and prosthetic compromises. Guided implant surgery (GIS) has been used as the means to achieve ideal implant placement. GIS refers to the process of digital planning, custom-guide fabrication, and implant placement using the custom guide and an implant system-specific guided surgery kit. GIS includes numerous additional steps beyond the initial prosthetic diagnosis, treatment planning, and fabrication of surgical guide. Substantial errors can occur at each of these individual steps and can accumulate, significantly impacting the final accuracy of the process with potentially disastrous deviations from proper implant placement. Pertinent overall strategies to reduce or eliminate these risks can be summarized as follows: complete understanding of the possible risks is fundamental; knowledge of the systems and tools used is essential; consistent verification of both diagnostic and surgical procedures after each step is crucial; proper training and surgical experience are critical. This review article summarizes information on the accuracy and efficacy of GIS, provides insight on the potential risks and problems associated with each procedural step, and offers clinically relevant recommendations to minimize or eliminate these risks.

Bone heat generated using conventional implant drills versus piezosurgery unit during apical cortical plate perforation

The apical portion of the implant osteotomy receives less irrigation and cooling during surgical preparation. High bone temperature, above the critical 10°C threshold, may impair osseointegration, particularly around dense cortical bone. The aim of this study was to evaluate the apical cortical plate temperature increase with two different devices and pressure loads in a porcine rib ex vivo model. A total of 24 implant sites were prepared on porcine ribs, divided into 4 groups of 6 samples each, according to the device used (conventional drill system or piezosurgery) and pressure load applied (1,000g or 1,500g). A rubber dam was used to isolate the apical cortical plate from the cooling effect of irrigation. Temperature variation measurements were taken using an infrared thermometer. The piezosurgery unit was two times more likely to increase the osteotomy temperature by 10°C (OR=2; 95% CI 1.136, 3.522; P<0.05). The average temperature increase was 0.07°C (SD=0.10) for group 1 (drill system 1,000g); 0.22°C (SD=0.26) for group 2 (drill system 1,500g); 9.18°C (SD=4.51) for group 3 (piezosurgery 1,000g); and 8.17°C (SD=6.12) for group 4 (piezosurgery 1,500g). The piezosurgery site preparation had significantly higher temperature increase than did the conventional drill site preparation (P<0.05). There was no statistically significant difference in temperature change between the two pressure loads applied (P=0.78). Temperature increases exceeded the critical 10°C threshold in half of the samples prepared with the piezoelectric device. Bone overheating using a piezosurgery unit is a potential risk during implant site preparation. The piezosurgical device resulted in significantly higher temperatures than did conventional drilling at the apical cortical portion of the osteotomy. The temperature increase was often higher than the critical 10°C threshold.

Reliability of cone beam computed tomography as a biopsy-independent tool in differential diagnosis of periapical cysts and granulomas: An In vivo Study.

Background:Differential diagnosis of periapical cysts and granulomas is required as their treatment modalities are different.Aim:The aim of this study was to evaluate the efficacy of cone beam computed tomography (CBCT) in the differential diagnosis of periapical cysts from granulomas.Settings and Design:A single-centered observational study was carried out in the Department of Conservative Dentistry and Endodontics, Dr. R. Ahmed Dental College and Hospital, using CBCT and dental operating microscope.Methods:Forty-five lesions were analyzed using CBCT scans. One evaluator analyzed each CBCT scan for the presence of the following six characteristic radiological features: cyst like-location, shape, periphery, internal structure, effect on the surrounding structures, and cortical plate perforation. Another independent evaluator analyzed the CBCT scans. This process was repeated after 6 months, and inter- and intrarater reliability of CBCT diagnoses was evaluated. Periapical surgeries were performed and tissue samples were obtained for histopathological analysis. To evaluate the efficacy, CBCT diagnoses were compared with histopathological diagnoses, and six receiver operating characteristic (ROC) curve analyses were conducted.Statistical Analysis Used:ROC curve, Cronbach's alpha (α) test, and Cohen Kappa (κ) test were used for statistical analysis.Results:Both inter- and intrarater reliability were excellent (α = 0.94, κ = 0.75 and 0.77, respectively). ROC curve with regard to ≥4 positive findings revealed the highest area under curve (0.66).Conclusion:CBCT is moderately accurate in the differential diagnosis of periapical cysts and granulomas.

Submandibular fossa augmentation in implant dentistry.

Background:There are two limiting factors for determining the dental implant fixture length in mandibular posterior edentulous region: Inferior dental canal and submandibular fossa.Purpose:Submandibular fossa augmentation is a suggested way to overcome the problem of lingual undercut beneath the mylohyoid ridge in implant dentistry.Materials and Methods:Patients with lingual posterior bony undercut that interferes with the placement of a standard implant with a length of 10 mm were enrolled in this study.Results:This method was used for eight patients in 10 sites. Increased implant length and decreasing the chance of sublingual hematoma due to lingual cortical plate perforation are the results of this study.Conclusions:Submandibular fossa augmentation is a new technique to improve the maneuver of oral surgeons to increase dental implant length in the presence of deep lingual bony undercut.

Expression of astrocyte elevated gene-1 protein in ameloblastomas, keratocystic odontogenic tumors, and dentigerous cysts.

Benign epithelial odontogenic tumors such as ameloblastoma and keratocystic odontogenic tumor (KCOT) may exhibit an aggressive clinical course reminiscent of malignancies. Recent studies have indicated that astrocyte elevated gene-1 (AEG-1) is highly expressed in a variety of malignant neoplasms and its overexpression is associated with tumor invasion, metastasis, and poor survival. However, the role of AEG-1 in odontogenic tumors and cysts is still undiscovered. Immunohistochemical staining of AEG-1 was performed in 42 cases of ameloblastoma, 29 cases of KCOT, and 19 cases of dentigerous cyst. Correlations between AEG-1 expression and clinical parameters of ameloblastomas or KCOTs were statistically analyzed. AEG-1-positive staining was found in 37 (88%) of 42 ameloblastomas and in 24 (83%) of 29 KCOTs. None of 19 dentigerous cysts were positive for AEG-1 protein. For ameloblastomas, AEG-1 protein expression was significantly higher in ameloblast-like cells than in stellate reticulum-like cells (P = 0.003). For KCOTs, AEG-1 protein was diffusely expressed in all lining epithelial cells except the superficial parakeratinized cells. Moreover, the frequency of cortical plate perforation was significantly higher in ameloblastomas with high AEG-1 expression than in ameloblastomas with low or negative AEG-1 expression (P = 0.043). Significantly higher expression of AEG-1 protein in ameloblastomas and KCOTs than in dentigerous cysts and significantly greater frequency of cortical plate perforation in high AEG-1-expressed ameloblastomas than in low or negative AEG-1-expressed ameloblastomas may imply the high potential of AEG-1 to serve as a locally invasive biomarker and a target for novel therapy.

Odontogenic Myxoma of Mandible: Report of A Rare Case.

Odontogenic Myxoma of Mandible: Report of A Rare Case.

A rare case of benign aggressive cementoblastoma

Cementoblastoma is considered to be a rare odontogenic neoplasm of mesenchymal origin. The World Health Organization classified benign cementoblastoma and cementifying fibroma as the only true cemental neoplasms. This is a case of cementoblastoma which has shown an unusual local aggressiveness causing lingual cortical plate perforation, which is a rare presentation of this lesion. Radiographic and histologic findings along with the treatment plan are described in detail.

Tomographic evaluation on bone morphology in posterior mandibular region for safe placement of dental implant.

The aim of this study was to examine the morphology of submandibular fossae at edentulous posterior regions of dried mandibles and to determine a safe range for proper lingual angulation during the placement of a dental implant in the posterior mandibular region, with a computerized tomographic scan study. Spiral computed tomographic images of 77 dry adult human mandibles were evaluated to determine the deepest area in the submandibular fossa. Then, the proper lingual angulations for the placement of a dental implant at these regions were measured. Pearson's correlation coefficient was calculated to show the relation between the depths of submandibular fossa and lingual implant angulations. "Paired t test" was used for differences between the lingual implant angulations and the depths of submandibular fossa on each side of the mandibles. Depths of the submandibular fossa and lingual implant angulations were varied between 1.1 and 4.6 mm: 62°-84° on right side of the mandibles, and 1.1-4.5 mm, 65°-83° on left side of the mandibles. There were statistically medium negative correlations between the degree of lingual implant angulations and the depth of submandibular fossa on each side of the mandible (r = -0.44, p < 0.001, and r = -0.38, p = 0.001). There was a statistically significant difference between the right and left sides of the mandibles in terms of the depth of submandibular fossa (p = 0.01). Within the limits of this study, the depth of submandibular fossa was measured as ≥ 2 mm in around 71.5 % of examined regions, and lingual implant angulations were between 62° and 84°. These results may be considered by clinicians who are planning the dental implant placement in posterior mandible to avoid potential risk of lingual cortical plate perforation.

Glandular odontogenic cyst: A diagnostic challenge

Glandular Odontogenic Cyst (GOC) is a developmental cyst of the jaw. It is clinically rare and histopathologically unusual type of odontogenic cyst with unpredictable and potentially aggressive behavior. It was first described in 1987 by Padayachee and Van Wyk. Since its first description, till date 114 cases have been reported in English literature. It usually occurs above 40 years of age and in the anterior region of mandible. Radiographically, it appears as either unilocular or multilocular well defined radiolucent lesion. Usually thinning and perforation of cortical plate is associated with GOC, indicating aggressiveness of the lesion. The clinical and radiographic features are not specific, and it can mimic as any other destructive lesion of the jaw. GOC has tendency to grow to a large size and propensity toward recurrence. Histologically, it can be easily misdiagnosed as a central muco-epidermoid carcinoma. The aim of this paper is to present an unusual case of GOC in a 21 year old male, which was clinically and radiologically diagnosed as a dentigerous cyst associated with an impacted third molar tooth of mandible; and also to review the main criteria for accurate diagnosis.

Intraoperative computerized navigation for flapless implant surgery and immediate loading in the edentulous mandible

Computerized navigation surgery has evolved to facilitate minimally invasive procedures, the gold standard of surgery today. While flapless implant surgery may be clinically beneficial, it has generally been perceived as a blind procedure limited to straightforward cases that do not pose a risk of cortical plate perforation. The objective of this report is to describe a protocol for flapless implant placement in a completely edentulous mandible using computerized navigation surgery. The Image Guided Implantology system (IGI, DenX Advanced Dental Systems) is described. The IGI system provides real-time imaging of the dental drill and transforms flapless implant surgery into a fully monitored procedure. The highly accurate intraoperative navigation enables precise transfer of the detailed presurgical implant plan to the patient. This is particularly valuable in edentulous jaws lacking any indication of the dental arch. The accurate positioning of the implants, based on the presurgical digital plan, allows fabrication of a provisional fixed prosthesis before the implant surgery for immediate postoperative loading. This innovative protocol can enhance prosthodontic-driven placement of implants in a fully monitored flapless surgery.—<i>Reprinted with permission of Quintessence Publishing.</i>