Three-dimensional evaluation of angular,linear, and resorption features of maxillary impacted canines on cone-beam computed tomography

Objectives

The aim of this study was to evaluate the localization, angulation, and resorption features of maxillary impacted canines on cone-beam computed tomography (CBCT).

Methods

This retrospective study examined the CBCT scans of 140 maxillary impacted canines in 102 patients (43 males, 59 females; mean age: 16.25 ± 6.31 years). The following impacted canine-related parameters were analyzed on the CBCT images: impaction side; location; root resorption levels of adjacent teeth; occlusal plane and midline distances of impacted canines; and angulations of impacted canines to midline, lateral incisor, and occlusal plane.

Results

Bilateral canine impaction was found in 38 subjects, and unilateral canine impaction was present in 64 subjects. Severe resorption was found in 14 canines. There were no significant differences between the occlusal plane and midline distances to the impacted canine cusp tip and root apex (p > 0.05). The midline angulation of right maxillary impacted canines was significantly higher than that of left maxillary impacted canines (p < 0.05), while the occlusal plane angulation of left maxillary impacted canines was significantly higher than that of right maxillary impacted canines (p < 0.05).

Conclusions

Maxillary canine impaction was more frequently seen in female subjects than in male subjects. Lateral incisors were more frequently affected than first premolars, and slight resorption was more frequently seen in adjacent teeth. CBCT assessment of maxillary impacted canines can provide accurate measurements of angular, linear, and resorption parameters.

     

Comparison of Erich arch bar versus embrasure wires for intraoperative intermaxillary fixation in mandibular fractures

Purpose

Intermaxillary fixation (IMF) is a fundamental principle in the management of mandibular fractures but with recent advent of open reduction and internal fixation (ORIF), use of IMF is almost limited intraoperatively. Therefore, we compared the efficacy of Erich arch bar versus embrasure wires for intraoperative IMF in mandibular fractures.

Method

This prospective study was comprised of 50 patients with mandibular fractures who required ORIF with intraoperative IMF. Patients were categorized into two groups of 25 patients each: Erich arch bar technique was used for group A and embrasure wire technique for group B. Parameters were time taken for IMF, needle stick injury, occlusal stability, iatrogenic complications, and periodontal status of patients.

Statistical analysis

Chi-squared test and unpaired t test analyses was run on IBM SPSS 21.0 version (2015) software.

Result

Mean time for placing embrasure wire (3.48 min) was significantly less than that for Erich arch bar (48.08 min). Needle stick injury rates to the operator as well as the assistants were significantly less when using the embrasure wire than the Erich arch bar. The Erich arch bar had significantly superior postoperative occlusion stability. Iatrogenic injury was more common when placing the Erich arch bar than the embrasure wire. Postoperative oral hygiene status was good in patients that received the embrasure wire.

Conclusion

Embrasure wire technique is a quick, easy, and reliable technique for minimally or moderately displaced fractured mandible and had better clinical outcomes than did patients that underwent the Erich arch bar technique.

     

Superolateral Dislocation of Bilateral Intact Mandibular Condyles: A Rare Case Series

Background and Purpose

The dislocation of mandibular condyle is a clinical condition in which the head of condyle has been displaced out of the glenoid fossa. Complete dislocation of the mandibular condyle can occur in anterior, posterior, lateral and superior direction. Among these dislocations, bilateral superolateral dislocation of mandibular condyles is quite rare and often misdiagnosed. Because of its rare occurrence and unusual clinical course, the best treatment is debatable.

Patients and Method

We present the first case series of true bilateral superolateral dislocation of intact mandibular condyles (Type 2B) without fracturing the Zygomatic arch, associated with symphysis fracture.

Conclusion

This article intends to provide information regarding the possible biomechanics and management of bilateral superolateral dislocation of mandibular condyles associated with symphysis fracture.

     

Mandibular Reconstruction: Overview

Introduction

Mandibular reconstruction has changed significantly over the years and continues to evolve with the introduction of newer technologies and techniques.

Purpose

This article reviews the history of oromandibular reconstruction, biomechanics of mandible, summarizes the reconstruction options available for mandible with defect classification, goals in reconstruction, the various donor sites, current reconstructive options, dental rehabilitation and persistent associated problems.

Summary

Oromandibular reconstruction, although a challenge for the head and neck reconstructive surgeon, is now reliable and highly successful with excellent long-term functional and aesthetic outcomes with the use of autogenous bone grafts and current reconstructive options. The ideal reconstruction would provide a solid arch to articulate with the upper jaw, restoring swallowing speech, mastication, and esthetics. Autogenous vascularized bone grafts in combination with microsurgical techniques have revolutionized mandibular reconstruction in oral cancer surgery. Current trends in mandibular reconstruction aim to achieve reestablishment of a viable mandible of proper form and maxillary mandibular relationship while decreasing the need for invasive autogenous graft procurement. However the optimal reconstruction of mandibular defects is still controversial in regards to reconstructive options which include the donor site selection, timing of surgery and method of reconstruction.

     

The reproducibility of assessment of white spot lesions adjacent to orthodontic brackets,with a quantitative light induced fluorescence digital camera at different rotations of teeth – an in vitro study

Background

A quantitative light-induced fluorescence digital (QLF-D) camera is able to assess demineralizations adjacent to orthodontic brackets. Rotations of teeth during and the presence of the orthodontic appliances may influence the longitudinal follow-up of such lesions over time.

Methods

Brackets were bonded on extracted teeth: 54 incisors and 31 canines. Demineralizations were formed in vitro directly cervical of the bracket. Images were captured using a QLF-D camera mounted on an optical bench, equipped with a goniometer on a turntable. The teeth were placed in the goniometer simulating buccolingual rotation (0°, 10°, 20°), the turn-table was used for mesiodistal rotations (0°, 10°, 20°). Standardized QLF-D images were made before (with and without a wire) and after debonding at combinations of aforementioned angles of rotation. The image after debonding at 0° buccolingual and 0° mesiodistal rotation served as a control.

Results

The presence of a bracket resulted in a significantly higher fluorescence loss, yet a smaller lesion area (p < 0.05) in comparison to the control. A significant higher fluorescence loss was seen for rotations towards lingual relative to the 0° buccolingual and 0° mesiodistal rotation, while the effect was less explicit towards buccal.

Conclusions

Fluorescence loss and lesion size are influenced by the angle of rotation under which the demineralization is photographed. The full extent of demineralizations is only apparent after debonding when photographed at rotations of 0° mesiodistal and up to 20° buccal. Precaution must be taken into account assessing demineralizations of patients undergoing treatment with fixed appliances when using a QLF-D camera.

     

Arch Wire: A Novel Technique for Intra-Maxillary Fixation

Introduction

Arch bars are regularly used in the management of dentoalveolar and minimally displaced fractures of the maxilla or mandible and luxation or avulsion of teeth by maxillofacial surgeons. The procedure for arch bar placement has remained unchanged over the period of years, and this coupled with the difficulty in maintenance of oral hygiene is a problem that begs attention.

Technique

We have devised a technique to overcome these hurdles and achieve adequate intramaxillary splinting. The technique uses an arch wire and ligature wire assembly instead of the conventional arch bar.

Conclusion

This technique is easy to learn and can thus be used as a rapid yet robust alternative to the conventional arch bar for dentoalveolar and minimally displaced fractures.

     

Osteoporotic mandibular changes caused by type 2 diabetes mellitus: a comparative study by cone beam computed tomography imaging

Objectives

Studies on bone mineral density and fracture risk in diabetic patients have attracted interest in the last few years. This study was aimed at comparing mandibular osteoporotic changes assessed by qualitative and quantitative radiographic methods in the mandibles of type 2 diabetes mellitus patients with those of non-diabetic subjects using cone beam computed tomographic images.

Methods

This quantitative and qualitative study of mandibular bone in diabetic patients included 23 type 2 diabetes mellitus patients and an equal number of healthy subjects. Radiomorphometric measurements were performed for each subject using cone beam computed tomography images. Changes in cortical bone thickness were determined by measuring bone area. Fractal dimension analysis was applied to evaluate the trabecular structure of the bone.

Results

No statistically significant difference could be established between the type 2 diabetes mellitus group and the control group in regard to either radiomorphometric measurements or fractal dimension analysis. Quantitative assessment of mandibular bone indicated a thinning of the cortical bone, with a statistically significant difference between the type 2 diabetes mellitus patients and the healthy controls.

Conclusions

Bone condition related to diabetes involves complex pathophysiological mechanisms; thus, radiographic imaging parameters may be useful as an adjunct to clinical parameters.

     

A Self-Retaining Lingual Flap Guarding Device During Surgical Removal of Impacted Mandibular Third Molar

Introduction

Lingual nerve damage is one of the common complications following mandibular third molar surgery. On considering the impact of lingual nerve damage on the patient’s quality of life, it is necessary to exercise caution to minimize its occurrence.

Material and methods

Although many lingual retractors are available, in this article we describe an indigenously designed lingual retractor for use in mandibular third molar surgery.

Conclusion

The indigenous lingual retractor described in this article provides advantages like clear access and excellent retention unlike conventional retractors.

     

Comparison of Efficacy of Transalveolar Screws and Conventional Dental Wiring Using Erich Arch Bar for Maxillomandibular Fixation in Mandibular Fractures

Introduction

Maxillomandibular fixation is required in nearly all cases of facial fractures which can be achieved by conventional dental wiring techniques or newer methods using transalveolar screws.

Material and Methods

A prospective randomized clinical study divided into two groups with thirty adult patients each with mandibular fractures was undertaken comparing the Maxillomandibular fixation technique using transalveolar screws and Erichs arch bar. Total time taken, rate of glove perforation, intraoperative and postoperative complications were noted in both the groups.

Results

The time taken for maxillomandibular fixation in minutes and rate of glove perforation was found to be statistically significantly less for transalveolar group compared to arch bar group (p < 0.05). However, there was no significant difference found in the oral hygiene and gingival status using the Glass index and Gingival index. The rate of screw breakage (04.67%), wire breakage (05.12%), non-vitality due to iatrogenic dental damage (01.66%), soft tissue injury and tooth loss were some of the noted complications during the study.

Conclusion

We found that transalveolar group offered advantages like less time taken with a definite decreased risk of percutaneous injury, while the iatrogenic complications like dental damage can be reduced by taking adequate precautions.

     

Factors affecting observer agreement in morphological evaluation of mandibular cortical bone on panoramic radiographs

Objectives

To assess intra- and inter-observer agreement in the morphological evaluation of mandibular cortical bone on panoramic radiographs, to examine factors affecting the diagnosis, and to determine causes of diagnostic discrepancy.

Methods

Three experienced observers evaluated mandibular cortical shape on panoramic radiographs of 228 females, and divided the images into three classes. The intra- and inter-observer agreements were calculated. The effect of mandibular cortical width on shape classification was examined. Causes of diagnostic discrepancy were investigated.

Results

Overall intra- and inter-observer kappa values in diagnosing mandibular cortical shape were 0.58–0.76 and 0.62–0.69, respectively. The kappa values in diagnosing Class 2 were low. In radiographs diagnosed as Class 2 and Class 3, the ranges of mandibular cortical width overlapped. Discrepancies in diagnosis were caused by slight resorption at the endosteal margin of the cortical bone, endosteal cortical residues near the thinned smooth cortex, and superimposition of the hyoid bone over the mandible.

Conclusions

Inter-observer agreement in evaluating mandibular cortical shape was moderate to substantial. Diagnostic discrepancies were mainly caused by differences in evaluation of the endosteum near the cortical bone.

     

The Jugaad Technique for Jaw Reconstruction: Denture Based Inverse Planning

Aim

The aim of this clinical paper is to introduce a technique to plan for functional maxillofacial reconstructions.

Materials and Methods

Preoperative dental casts were made of the patient and mock surgery performed on the casts. A fibula analogue was then placed in an ideal functional reconstruction position. New dentures were fabricated on the fibula analogue and drill holes for the placement of implants were placed through the denture. This denture formed as a guide to position the fibula transplant during surgery.

Results

This technique was useful in producing functional and rehabilitative outcomes in cases of both maxillary and mandibular reconstructive surgeries.

Conclusion

The Jugaad technique—denture based inverse planning—is a cost effective method for planning and executing maxillofacial reconstructions using mock surgery on casts and interim dentures.

     

Anesthetic Efficacy of 4 % Articaine During Extraction of the Mandibular Posterior Teeth by Using Inferior Alveolar Nerve Block and Buccal Infiltration Techniques

Introduction

The study was designed to evaluate the anesthetic efficacy of 4 % articaine with 1:100,000 epinephrine (A100) in infiltration and inferior alveolar nerve block (IANB) anesthetic techniques for the pain control during extraction of the mandibular posterior teeth.

Methods

This prospective randomized single-blind clinical trial included 100 patients needing extraction of at least two mandibular molars. Patients received either infiltration in the buccal vestibule opposite to the first molar supplemented with lingual infiltration or standard IANB with A100. For assessment of depth of anesthesia obtained by the two anaethetic techniques, presence or absence of pain during the extraction were rated using the visual analog scale.

Results

Fifty patients received infiltration anesthesia and fifty patients were anesthetized by IANB. The success rate of pain-free extraction after buccal infiltration was 94 %, whereas by using IANB with the same anesthetic it was 92 %. No statistical differences were detected in the success rates between the two anesthetic techniques (P = 0.15).

Conclusions

Buccal Infiltration can be considered a good option during extraction of the mandibular molar and premolar teeth of course, with supplemental lingual anesthesia.

     

Effect of gamma irradiation on the wear behavior of human tooth dentin

Objectives

The objective of this study was to evaluate the effect of gamma irradiation on the wear behavior of human tooth dentin in terms of possible alterations in crystallinity, grain size, and composition.

Materials and methods

Human premolars (n = 19) were collected to obtain the perpendicular or parallel to the direction of the dentin tubule specimens. Each specimen was subjected to 60 Gy of gamma irradiation, in daily increments of 2 Gy. The nanoscratch tests were conducted. The scratch traces were observed via scanning electron microscope (SEM) and surface profilometer. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to investigate the alteration of crystallography and chemical composition of dentin after irradiation. The change of surface microhardness (SMH) was also evaluated.

Results

The nanoscratch results showed that the friction coefficient of dentin after irradiation became higher, and the depths and widths of scratch were greater than that of dentin before irradiation. Additionally, irradiation decreased the crystallinity of dentin and induced the formation of bigger crystals. The carbonate/mineral ratio was increased. Furthermore, a significant reduction in microhardness after irradiation was observed. The main damage mechanisms consisted of the formation of delamination and crack in both the specimens cut perpendicular and parallel to tubule dentin after irradiation.

Conclusion

Irradiation affected directly the wear behavior of tooth dentin, accompanied by the alterations in crystallography, chemical composition, and surface microhardness of dentin.

Clinical relevance

This would help extend understanding the influence of irradiation on dentin and provide suggestions for selecting more suitable materials for irradiated tooth.

     

Intraosseous Leiomyoma of the Mandible: A Case Report of the Rare Entity and Review of Literature

Introduction

Leiomyoma is a rare tumor of smooth muscle origin with a very low incidence in the maxillofacial region. Intraosseous occurrence of oral leiomyoma is even rare with involvement of mandible followed by maxilla.

Aim

The purpose of this paper is to present a case of intraosseous leiomyoma of the left mandibular angle region with the review of literature describing this rare entity. The paper also highlights the need to include this entity in differential diagnoses of jaw lesions.

Material and Method

An extensive search of literature was carried out on the Medline-Pubmed and Google Scholar database using the keywords leiomyoma, maxilla, mandible, oral and palate to thoroughly search and collect all the reported cases of intraosseous leiomyoma.

Result

To the best of our knowledge till date only 22 cases of intraosseous leiomyoma have been reported in the maxillomandibular region we represent the 23rd case of the intraosseous leiomyoma in a 36 year old male patient.

Conclusion

Though uncommon but it is known to occur in the jaws therefore intraosseous leiomyoma should be included in the list of differential diagnoses of radiolucent lesion of mandible and maxilla.

     

Restorative material and loading type influence on the biomechanical behavior of wedge shaped cervical lesions

Objectives

To evaluate the influence of restorative materials used on the rehabilitation of MOD cavities and loading type, on biomechanical behavior of wedge-shaped (WS) lesions in endodontically treated maxillary premolars. The investigation was conducted by 3D finite element analysis (FEA) and strain gauge test.

Materials and methods

Six models were generated, with MOD cavities and endodontic treatment: A (MOD amalgam restoration), R (MOD composite restoration), AL (A + cervical lesion (L)), RL, ALR (A + cervical lesion restored with composite (LR)), and RLR. Each model underwent two compressive loading (100N): axial and oblique—45° angle to the long axis on the buccal cusp. The models were analyzed by von Mises criteria. For strain gauge test, 14 standardized maxillary premolars were treated according to the groups described for FEA. Two strain gauges were bonded on each sample submitted to compressive loading in a mechanical testing machine.

Results

A presented higher stress concentration and strain values than R. Oblique loading promoted highest stress concentration and strain rates for all groups. ALR and RLR presented similar stress–strain distribution pattern when compared to A and R.

Conclusion

The interaction between MOD cavity restored with amalgam and oblique loading propitiated the highest stress concentration and strain values on cervical region and WS lesion.

Clinical relevance

The MOD cavity restored with composite resin is a better option than amalgam to improve the biomechanical behavior of wedge-shaped lesion, avoiding dental failure. In addition, the occlusal interferences must be removed, allowing homogeneous contact distribution and preventing WS lesion progression.

     

Comparison of 3D plate and locking plate in treatment of mandibular fracture—a clinical study

Introduction

This study was performed to evaluate the efficacy and post-operative complication of 3-dimensional (3D) titanium miniplate and locking plate in mandibular fractures (parasymphysis, symphysis, body, and angle).

Materials and methods

Forty patients, with non-comminuted mandibular fractures treated with open reduction and internal fixation using 3D titanium miniplate system or locking plate system through an intra-oral approach, were included in this study. All patients were systematically monitored up to 2 months post-operatively. Parameters recorded were infection, occlusal discrepancies, hardware failure, wound dehiscence, sensory disturbance of the inferior alveolar nerve, and stability of fractured segments.

Results

Forty patients with mandibular fracture were divided into two groups randomly without any bias. The fractures of all 40 patients were found to be adequately fixed when checked intra-operatively after fixation. One patient (2.5%) of the 3D plate group developed an infection on the first and second post-operative visit and was treated by antibiotic coverage. One patient in the locking plate group (2.5%) reported wound dehiscence after the first week follow-up.

Conclusion

Both 3D titanium miniplates and locking plate are effective in the treatment of mandibular fractures, and overall complication rates are lesser. However, the 3D plating system uses less hardware in cases of parasymphysis and symphysis fractures and more hardware in cases of body and angle fractures.

     

Internal fixation of single mandibular fracture under mandibular nerve block

Objective

The aim of this study was to assess the results of open reduction and internal fixation (OR/IF) of isolated mandibular fracture under regional anesthesia using mandibular nerve block.

Patients and methods

This prospective study was carried out on 44 patients who had isolated traumatic parasymphyseal mandibular fractures. All patients were managed by OR/IF by two titanium miniplates using manual maxillomandibular fixation (MMF). All patients were sedated by (0.05 mg/kg) midazolam and (2 μg/kg) fentanyl. The patients were randomly classified into two groups: the control group (22 patients) treated under general anesthesia (GA) and the study group (22 patients) repaired under regional anesthesia. The results were assessed as regards dental occlusion, average intrinsic vertical mouth opening, actual operative time, complication, tolerance and patient’s satisfaction, and postoperative hospital stay time.

Results

Both groups were matched for age and sex. There were no statistically significant differences of the postoperative complication, dental occlusion, and mouth opening between both groups. Duration for anesthesia induction, intubation, and anesthesia recovery was not needed in regional anesthesia. Regional anesthesia was tolerable and highly satisfactory in all patients with no intraoperative or postoperative anesthesia-related problems and no reported complications.

Conclusion

Regional anesthesia can effectively replace GA in selected cases of mandibular fracture obviating the risks of GA.

     

Mandibular war injuries caused by bullets and shell fragments: a comparative study

Purpose

Is to compare the patterns, severity, and management of the high- and low-velocity mandibular war injuries managed at Al Shaheed Gazi Al-Hariri Hospital in Baghdad Medical City, Iraq, during a 2-year period.

Methods

Forty-one patients with a history of mandibular war injuries treated by our maxillofacial team were reviewed during a period of 2 years (2015–2017). All patients were treated in the Maxillofacial Unit of the Hospital of Specialized Surgeries in Baghdad Medical City.

Results

A 2-year retrospective study evaluated 41 patients with mandibular war injuries with a total of 94 fractures (comminution represents 79.06% of the bullet injuries, while it is only 62.74% with IED injuries). Management of these injuries was varied according to the severity of the injuries and resources available. Close reduction was used in 72.72% of the linear fracture cases, whereas open technique was used in 56.6% of the comminuted fractures.

Conclusions

Bullet injuries were associated with a higher number of mandibular comminuted fractures, in addition to more extensive bone loss. While shell injuries of IED (improvised explosive devices), on the other hand, were associated with higher infection rate and more postoperative complication.

     

Fate of Costochondral Graft in Temporomandibular Joint Reconstruction: A Histological Study

Objective

To asses the fate of the costochondral graft (CCG) used to stimulate mandibular growth in the management of Temporomandibular joint (TMJ) reconsrtuction in ankylosis—histologically.

Materials and Methods

Ten patients who had undergone CCG grafting for TMJ ankylosis between 1994–2009 in the department of Oral & Maxillofacial Surgery, Tamil Nadu Govt Dental College and Hospital, Chennai and had come back with reankylosis, were surgically explored and the graft along with the ankylotic mass was excised and evaluated histologically. There is no documented human study and clinically it is not possible.

Results

Histological evaluation revealed the presence of osseous tissue, fibrous tissue and osteocytes but no evidence of any chondroid tissue.

Conclusion

Our study showing the absence of chondroid tissue raises the question on the rationale of CCG in TMJ reconstruction when other interpositional gap arthroplasty can achieve a disease free joint.