Three-dimensional finite element analysis of zygomatic implants for rehabilitation of patients with a severely atrophic maxilla.

STATEMENT OF PROBLEM: Stresses applied to zygomatic implants have been determined to be transferred mainly to the zygomatic bone; however, consensus regarding the stress distribution pattern in the bone surrounding zygomatic implants has not yet been reached. PURPOSE: The purpose of this 3-dimensional (3D) finite element analysis (FEA) study was to visually compare the stress distribution pattern in 2 different zygomatic implant treatment modalities and evaluate the effect of masseter musculature involvement. MATERIAL AND METHODS: A 3D FEA craniofacial model was constructed from the computed tomography (CT) data of a selected patient with a severely atrophic edentulous maxilla. Modeled zygomatic and conventional implants were inserted into the craniofacial model supporting a prosthesis superstructure. Two types of treatment were considered in the study: 2 zygomatic implants placed bilaterally or 2 zygomatic implants placed in conjunction with at least 2 conventional implants at the anterior maxilla. The models were loaded with a vertical force of 150 N, a lateral force of 50 N, and a distributed occlusal force of 300 N applied to the insertion area of the masseter muscle. The stresses on and deformations of the bones and implants were then observed and compared with and without the involvement of the musculature component. RESULTS: The stresses were distributed efficiently along the vertical and horizontal facial buttresses, as in the dentate skull; however, a difference in distribution pattern was observed when the models were loaded without applying the muscle component. The maximum deformation of bones surrounding the implants occurred in the abutment connection of the conventional anterior implant in the model with an additional conventional anterior implant. CONCLUSIONS: The FEA revealed the stresses were distributed efficiently along the vertical and horizontal facial buttresses, as in the dentate skull. However, the stresses in both models were concentrated in the zygomatic bone when incorporating the muscle component. Therefore, incorporating muscular force into FEA studies could affect the analysis result.

Can Oral TB develop in susceptible individuals after an oral surgical procedure? 3 case reports.

As opposed to the popular assumption, there have been an increase in the cases of Oral Tuberculosis as of late. Owing to increased drug resistance, there has been a change in the disease pattern leading to an upsurge in the Extra-pulmonary Oral Tuberculosis. According to the WHO, Diagnosis is the first step in the control of TB; but due to the lack of pathognomonic signs associated with Oral Tuberculosis and the rarity of these lesions, diagnosis is often difficult. So, to enable a timely diagnosis, we point out the occurrence of such lesions in the post-operative refractory lesions in susceptible individuals. However, a thorough search of literature did not yield any conclusive results. In this paper we present the clinical, radiographic and histopathological findings of three cases between the ages of 5 and 50 years old who were diagnosed of Oral Tuberculosis. These patients have undergone a recent oral surgical procedure prior to the development of Oral TB lesions. More research is required to increase the awareness of the pattern of this disease and to enable a quicker diagnosis so that the overall morbidity and mortality is reduced.

Accuracy Comparison between Robot-Assisted Dental Implant Placement and Static/Dynamic Computer-Assisted Implant Surgery: A Systematic Review and Meta-Analysis of In Vitro Studies.

Background and Objectives: The present systematic review and meta-analysis undertake a comparison of studies that examine the accuracy of robot-assisted dental implant placement in relation to static computer-assisted implant surgery (SCAIS), dynamic computer-assisted implant surgery (DCAIS), and freehand procedures. This study aims to provide a comprehensive understanding of the precision of robot-assisted dental implant placement and its comparative efficacy in relation to other placement techniques. Methods: The guidelines recommended by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were used to organize and compose this review. Four electronic databases (PubMed, Web of Science, Scopus, and Cochrane) were systematically searched for pertinent articles. Articles were selected following the inclusion and exclusion criteria. Qualitative and quantitative analyses of the selected articles were performed. Results: The initial electronic search resulted in 1087 hits. Based on the inclusion and exclusion criteria, five articles were selected for qualitative analysis, out of which three were considered for quantitative analysis. Three parameters were considered for accuracy evaluation (angular, coronal, and apical deviation). The mean angular deviation was -1.22 degrees (95% CI, -1.06--1.39), the mean coronal deviation was -0.15 mm (95% CI, -0.24--0.07), and the mean apical deviation was -0.19 mm (95% CI, -0.27--0.10). Conclusions: The robotic implant system was found to have significantly lower angular deviations and insignificantly lower coronal and apical deviations compared to DCAIS. Within the limitations of this review, it can be concluded that robot-assisted implant placement in resin models permits higher accuracy compared to DCAIS and SCAIS systems. However, due to the limited number of comparative studies with high heterogeneity, the findings of this review should be interpreted with caution. Further research is necessary to confirm the clinical application of robotics in implant surgery.

Zygomatic implant-supported prosthetic rehabilitation of a patient with Brown et al. Class II c maxillary defect: A clinical report.

The genesis of acquired maxillary defects poses a significant challenge when it comes to rehabilitating a patient prosthetically. These defects lead to functional and esthetic impairment, affecting the quality of life of an individual. This clinical report describes a satisfactory zygomatic implant-supported overdenture rehabilitation of a patient who underwent subtotal bilateral maxillectomy after an industrial accident. The result shows zygomatic implant-supported overdenture as a viable, predictable, and economical treatment option for a patient with an extensive maxillary defect.

An interdisciplinary approach for the management and rehabilitation of a fibro-osseous neoplasm using platelet-rich gel and an implant-supported hybrid prosthesis.

Fibro-osseous neoplasms such as central ossifying fibroma (COF) can lead to destructive expansile lesions involving the maxilla or the mandible. Management of such lesions usually involves surgical intervention in the form of enucleation or resection. Platelet-rich gel (PRG) has been known to expedite bone regeneration due to its osteoconductive property. PRG initiates a greater and faster initial cellular response in comparison to platelet-rich plasma and has better handling characteristics. The challenge in rehabilitation often occurs due to the size of the osseous defects postsurgery. Fixed prosthodontic rehabilitation with endosteal implants is a viable treatment approach in such cases, improving the oral health quality of life and masticatory efficiency, when compared to a removable partial denture. This case report describes the management of an extensive lesion of COF using PRG and rehabilitation with a screw-retained, implant-supported hybrid prosthesis.

The Efficacy of Fixation of Unilateral Mandibular Angle Fracture with Single 3D Plate vs Single Miniplate Using Transbuccal Approach.

Introduction: The management of mandibular angle fractures is often challenging and results in the highest rate of complications. The optimal treatment modality still remains controversial. This study was done to compare the treatment outcomes of single 3D plate versus single miniplate. Objective: The objective was to compare and evaluate the clinical and radiological outcome in patients who underwent treatment with single 3D plate versus single miniplate using transbuccal approach for unilateral angle fractures with other associated mandibular fractures. Methodology: A randomized control study was done in 12 patients with unilateral angle fracture who were divided into two groups. Group A patients were treated using single 3D plates, and Group B patients were treated using single miniplates. Study parameters were evaluated at different time intervals. Results: The results of the study showed that postoperatively in Group A, fracture reduction, occlusion and mouth opening were comparatively better than Group B. Hardware failure was seen in one patient in Group B. Postoperative morbidities showed no statistical difference. Conclusion: The single 3D plates showed a statistically insignificant advantage over single miniplates, although clinically Group A proved better than Group B with respect to the study parameters. Therefore, we recommend the use of single 3D plates for effective unilateral angle fracture treatment. More studies are required to prove the significant statistical significance.

3D Models Revolutionizing Surgical Outcomes in Oral and Maxillofacial Surgery: Experience at Our Center.

INTRODUCTION: New technological advances have revolutionized the field of oral and maxillofacial surgery. The three-dimensional (3D) models are new technological breakthroughs which have equipped the oral and maxillofacial surgeon to effectively reproduce or improve preoperative form and function. They have also allowed the surgeon to achieve minimal operative and postoperative morbidity. MATERIALS AND METHODS: In this case series, we present the clinical application and benefits of 3D models that are used for the surgical planning and execution of surgery in treating a case of mid-face deficiency and for the treatment of extensive jaw pathologies using reconstruction plate bent preoperatively, which contributed to improved surgical outcomes and patient satisfaction.

Prosthodontic rehabilitation of a sub-total maxillectomy defect with a definitive hollow obturator prosthesis using the modified lost-wax concept: A novel technique.

Squamous cell carcinoma (SCC) of the oral cavity is relatively common in the Indian subcontinent with surgical resection and adjuvant radiotherapy/chemotherapy being the treatment modality of choice. Prosthetic rehabilitation with an obturator following resection is more economical and yields satisfactory results. Better patient acceptance and comfort necessitates hollowing the prosthesis to a great extent. This novel method modifies the existing lost-wax technique in fabricating a definitive hollow maxillary obturator. An elderly man had reported to the Department of Prosthodontics with the chief complaint of a "big hole" in the mouth which affected his quality of life. He had undergone subtotal maxillectomy, following a histopathologic diagnosis of SCC, with adjuvant radiotherapy. Examination revealed an Aramany Class II defect with the healthy oral mucosa. A lightweight definitive obturator was designed and fabricated using a simple technique which utilizes easily available modeling wax. This article describes a relatively simple, single-step fabrication of a closed hollow-bulb obturator prosthesis with a uniform thickness of heat-cured resin encapsulating the hollow prosthesis.

Ameloblastic Fibrodentinoma: A Rarity in Odontogenic Tumors.

Ameloblastic fibrodentinoma is a rare, benign, mixed odontogenic tumor composed of odontogenic epithelium, immature connective tissue and is characterized by the formation of dysplastic dentin. An incidence of 0.1% is reported for this benign odontogenic tumor which indicates the rarity of this lesion. In the present review, a case of ameloblastic fibrodentinoma of the mandible in an african male is presented which was managed by surgical enucleation of the lesion along with the removal of impacted tooth associated with it.

Odontogenic maxillofacial space infections at a tertiary care center in North India: a five-year retrospective study.

OBJECTIVE: Odontogenic infections contribute to a significant proportion of maxillofacial space infections (MSI) across the world. MSI can cause several life-threatening complications despite skillful management. The objective of this study was to review the clinical characteristics, management, and outcome of odontogenic MSI treated at a tertiary care center, and to identify the factors predisposing to life-threatening complications. METHODS: A retrospective chart review of all patients treated for MSI from January 2006 to December 2010 at the Christian Medical College Hospital in Ludhiana, North India, was conducted. RESULTS: Out of 137 patients identified, 66.4% were men. Mean patient age was 40 years, and 24.1% of the patients were diabetic. The most common origin was pulpal (70.8%), the most common space involved was the submandibular space, and the most common teeth responsible were the lower third molars. Twenty patients (14.6%) developed complications. Diabetes, multiple space involvement, and a total leukocyte count of ≥15×10(9)/l were associated with complications. CONCLUSIONS: Patients with MSI who present with multiple space involvement, a high leukocyte count, and those with diabetes are at higher risk of developing life-threatening complications and need to be closely monitored.

Pattern of maxillofacial fractures at a tertiary hospital in northern India: a 4-year retrospective study of 718 patients.

PURPOSE: Pattern and aetiology of maxillofacial injuries varies from one country to another and even within the same country depending on prevailing socio-economic, cultural and environmental factors. Various studies have been carried out in various countries to study the epidemiology and demographics of the maxillofacial injuries but the studies from India are few. MATERIAL AND METHODS: Retrospective study was undertaken at Christian Medical College Ludhiana (India) from January 2006 to December 2009. Treatment records of the patients was checked and age, gender, aetiology of injury, associated injuries, maxillofacial fractures and treatment offered were recorded. RESULTS: A total of 1075 fractures were recorded in 718 patients, ranging from 11 months to 85 years of age. Male:female ratio was 6.6:1. Maxillofacial injuries were most common in third decade of life. A total of 517 patients suffered injuries because of road traffic accident, 115 because of accidental fall and 67 because of interpersonal violence. A total of 184 patients had 221 associated injuries of which 56.1% head injuries, 29.0% orthopaedic injuries and 14.9% other injuries were present. Of 596 middle third fractures, 29.8% were managed conservatively; for 21.7% and 48.7% of fractures, closed reduction and open reduction were performed respectively. Of 479 mandibular fractures, 1.8% was managed conservatively; for 16.7% and 81.5% fractures, closed reduction and open reduction were performed respectively. CONCLUSION: Better socio-economic status of people, increased vehicular movements and non-implementation of road safety norms have increased road traffic accidents. Proper education of the people who are most commonly involved in the RTA can be one of the possible ways to reduce the maxillofacial injuries.

Fine needle aspiration cytology: a diagnostic aid for oral lesions.

PURPOSE: Oral lesions usually lead to a diagnostic dilemma. Fine needle aspiration cytology (FNAC) is an important diagnostic aid for making a preoperative diagnosis of oral lesions. It does not supplant histopathology but augments it. MATERIALS AND METHODS: FNAC of oral lesions was undertaken in 45 patients, and all the lesions were subjected to histopathologic examination. Aspiration was performed with 23- to 25-gauge needles held in a Cameco syringe holder (Amar Udyog, Chandigarh, India). RESULTS: We diagnosed benign lesions in 22 cases, malignant lesions in 15, and inflammatory lesions in 7 by FNAC, whereas in 1 case the specimen was insufficient for diagnosis. One result was false negative, but there was no false-positive result. Specificity and sensitivity of FNAC were 95.45% and 93.75%, respectively. FNAC gave a diagnostic accuracy of 90.0% for benign lesions, 94.0% for malignant lesions, and 100% for inflammatory lesions. CONCLUSION: The procedure does not have any side effects or complications. Hence FNAC can be used as a reliable diagnostic aid for oral lesions because it is safe, accurate, convenient, and cost-effective.

Displacement of endodontic instruments in inferior alveolar canal.

Endodontic instrument breakage is a common occurrence during root canal treatment but the displacement of the separated instrument into the inferior alveolar canal is rare and has never been reported. We hereby present an unusual case of displacement of a separated instrument in the inferior alveolar canal and its retrieval by a simple technique.

Surgical Repositioning of a Dilacerated Impacted Incisor.

Dilaceration is one of the most common complications of trauma to deciduous dentition. The possible causes of dilaceration are trauma and developmental disturbances, while some authors suggest an association with some developmental syndromes. Dilaceration can be seen in both the permanent and deciduous dentition. The present case report describes surgical repositioning of a dilacerated impacted maxillary central incisor in a 9-year-old boy.