Incorporating 3-dimensional models in online articles

Evaluation of condylar and mandibular movements on the upper airway during the use of mandibular advancement device for obstructive sleep apnea treatment

OBJECTIVES

To evaluate the temporomandibular joint (TMJ), condylar and mandibular movements in obstructive sleep apnea (OSA) patients treated with mandibular advancement device (MAD) and to identify the influence of these anatomic factors on upper airway (UA) volume and polysomnographic outcomes after treatment.

MATERIALS AND METHODS

Twenty OSA patients were prospectively treated with MAD. Clinical examinations, cone-beam computed tomography, and polysomnography were performed before MAD treatment and after achieving therapeutic protrusion. Polysomnographic variables and three-dimensional measurements of the TMJ, mandible, and upper airway were statistically analyzed.

RESULTS

Condylar rotation, anterior translation, and anterior mandibular displacement were directly correlated with total UA volume, while vertical mandibular translation was inversely correlated with the volume of the inferior oropharynx. MAD treatment resulted in an increase in the volume and area of the superior oropharynx. There was no statistically significant correlation between condylar rotation and translation and polysomnographic variables. With MAD, there was a significant increase in vertical dimension, changes in condylar position (rotation and translation), and mandibular displacement. The central and medial lengths of the articular eminence were inversely correlated with condylar rotation and translation, respectively. The lateral length of the eminence was directly correlated with condylar translation, and the lateral height was directly correlated with condylar rotation and translation.

CONCLUSION

Condylar and mandibular movements influenced UA volume. The articular eminence played a role in the amount of condylar rotation and translation.

CLINICAL RELEVANCE

Individualized anatomical evaluation of the TMJ proves to be important in the therapy of OSA with MAD.

Realizing in-house algorithm-driven free fibula flap set up within 24 hours: a pilot study evaluating accuracy with open-source tools

Objective

This study aims to critically evaluate the effectiveness and accuracy of a time safing and cost-efficient open-source algorithm for in-house planning of mandibular reconstructions using the free osteocutaneous fibula graft. The evaluation focuses on quantifying anatomical accuracy and assessing the impact on ischemia time.

Methods

A pilot study was conducted, including patients who underwent in-house planned computer-aided design and manufacturing (CAD/CAM) of free fibula flaps between 2021 and 2023. Out of all patient cases, we included all with postoperative 3D imaging in the study. The study utilized open-source software tools for the planning step, and three-dimensional (3D) printing techniques. The Hausdorff distance and Dice coefficient metrics were used to evaluate the accuracy of the planning procedure.

Results

The study assessed eight patients (five males and three females, mean age 61.75 ± 3.69 years) with different diagnoses such as osteoradionecrosis and oral squamous cell carcinoma. The average ischemia time was 68.38 ± 27.95 min. For the evaluation of preoperative planning vs. the postoperative outcome, the mean Hausdorff Distance was 1.22 ± 0.40. The Dice Coefficients yielded a mean of 0.77 ± 0.07, suggesting a satisfactory concordance between the planned and postoperative states. Dice Coefficient and Hausdorff Distance revealed significant correlations with ischemia time (Spearman's rho = -0.810, p = 0.015 and Spearman's rho = 0.762, p = 0.028, respectively). Linear regression models adjusting for disease type further substantiated these findings.

Conclusions

The in-house planning algorithm not only achieved high anatomical accuracy, as reflected by the Dice Coefficients and Hausdorff Distance metrics, but this accuracy also exhibited a significant correlation with reduced ischemia time. This underlines the critical role of meticulous planning in surgical outcomes. Additionally, the algorithm's open-source nature renders it cost-efficient, easy to learn, and broadly applicable, offering promising avenues for enhancing both healthcare affordability and accessibility.

Surgically assisted maxillary expansion with or without pterygoid disjunction alters maxillomandibular positioning

PURPOSE

This study aimed to analyze alterations in mandibular positioning after surgically assisted maxillary expansion (SARME) with and without pterygoid disjunction (PD).

METHODS

Cone-beam computed tomography scans of 24 healthy individuals (18-45 years old) with transverse deficiency, superior to 5 mm, underwent SARME with or without PD. The aspects prospectively assessed were (1) alignment and position of the head (ITK-Snap and 3D Slicer software); (2) McNamara's and Steiner-Tweed-Wits' cephalometric analysis (Dolphin Imaging®); and (3) colorimetric evaluation based on 3D correspondence analysis (3D Slicer software).

RESULTS

A decrease in 1-NA and 1-SN angles as well as an increased occlusal plane in both groups was observed. Superior-inferior and anteroposterior spatial displacements of the chin were statistically significant in the PD group. Altered colorimetric patterns were also observed in the PD group.

CONCLUSIONS

This study found more evident tooth inclination in the group without PD; mandibular alterations were more evident in the PD group. Further studies with 3D analysis are strongly recommended for more comprehensive results.

The Airway Volume Related to the Maxillo-Mandibular Position Using 3D Analysis

Objective

The aim of this research was to compare three cephalometric analyses and their correlation with the airway volume in subjects with different skeletal classes using 2D and 3D images. Study Design. Cross-sectional descriptive study. Material and Method. Steiner, McNamara, and Ricketts analyses and the airway volume were compared in 115 subjects who were candidates for orthognathic surgery under diagnosis using cone beam computed tomography (CBCT); 46 males (40%) and 69 females (60%) were included. The sagittal positions of the maxilla and mandible, the angulation of the mandibular plane, the sagittal positions of the upper and lower incisors, measurements of the largest or shortest airway area, and the volume were compared using Spearman's test considering a p value < 0.05.

Results

Differences were observed between the Steiner and McNamara techniques for the sagittal position of the maxilla (p = 0.01). For mandibular angulation, there was a greater difference between values for Steiner and Ricketts techniques (p = 0.001). In the upper incisor, the results for McNamara and Ricketts techniques were significantly different (p = 0.004). Analysing the airway, subjects with a class II skeletal pattern had a smaller volume than those with a class III pattern (p = 0.034).

Conclusion

It may be concluded that skeletal class II patients have a significantly smaller airway volume than class III patients. The skeletal parameter does not always relate to the airway volume; however, the high mandibular angle could be related to the airway conditions.

A long-term longitudinal study of the osteoarthritic changes to the temporomandibular joint evaluated using a novel three-dimensional superimposition method

The aim of this study was to assess the changes in individual condyles from 5 to 8 years in patients with temporomandibular joint (TMJ) osteoarthritis using 3-dimensional cone beam computed tomography (3D CBCT) reconstruction and superimposition. To assess the longitudinal TMJ changes, CBCT was performed at initial (T₀) and final (T₂) timepoints that were at least 5 years apart and at a middle (T₁) timepoint. To improve the accuracy, we used a novel superimposition method that designated areas of coronoid process and mandibular body. The differences in the resorption and apposition amounts were calculated between each model via maximum surface distances. The greatest resorption and apposition observed were − 7.48 and 2.66 mm, respectively. Evaluation of the changes in each condyle showed that osteoarthritis leads to both resorption and apposition. Resorption was mainly observed in the superior region, while high apposition rates were observed (in decreasing order) in the posterior, lateral, and anterior regions. The medial parts showed greater apposition than the lateral parts in all regions. Our superimposition method reveals that both resorption and apposition were observed in condyles with TMJ osteoarthritis, and resorption/apposition patterns depend on the individual condyle and its sites.

Three-dimensional evaluation of dental decompensation and mandibular symphysis remodeling on orthodontic-surgical treatment of Class III malocclusion

INTRODUCTION

The purposes of this research were to identify the buccolingual inclinations of the mandibular teeth and the mandibular symphysis remodeling that result from the orthodontic decompensation movement.

METHODS

The sample consisted of 30 adults with Class III dentofacial deformity, who had presurgical orthodontic treatment. Three-dimensional images were generated by cone-beam computed tomography scans at 2 different times (initial and before orthognathic surgery). Three-dimensional virtual models were obtained and superimposed using automated voxel-based registration at the mandible to evaluate B-point displacement, mandibular molar and incisor decompensation movement, and symphysis inclination and thickness. The 3-dimensional displacements of landmarks at the symphysis were quantified and visualized with color-coded maps using 3D Slicer (version 4.0; www.slicer.org) software.

RESULTS

The measurements showed high reproducibility. The patients presented mandibular incisor proclination, which was consistent with the movement of tooth decompensation caused by the presurgical orthodontic treatment. Statistically significant correlations were found between the inclination of the mandibular incisors, symphysis inclination, and B-point displacement. Regarding the thickness of the symphysis and the inclination of the incisors, no statistically significant correlation was found.

CONCLUSIONS

The buccolingual orthodontic movement of the mandibular incisors with presurgical leveling is correlated with the inclination of the mandibular symphysis and repositioning of the B-point but not correlated to the thickness of the symphysis.

Midface Morphology and Growth in Syndromic Craniosynostosis Patients Following Frontofacial Monobloc Distraction

BACKGROUND

Facial advancement represents the essence of the surgical treatment of syndromic craniosynostosis. Frontofacial monobloc distraction is an effective surgical approach to correct midface retrusion although someone consider it very hazardous procedure. The authors evaluated a group of patients who underwent frontofacial monobloc distraction with the aim to identify the advancement results performed in immature skeletal regarding the midface morphologic characteristics and its effects on growth.

METHODS

Sixteen patients who underwent frontofacial monobloc distraction with pre- and postsurgical computed tomography (CT) scans were evaluated and compared to a control group of 9 nonsyndromic children with CT scans at 1-year intervals during craniofacial growth. Three-dimensional measurements and superimposition of the CT scans were used to evaluate midface morphologic features and longitudinal changes during the craniofacial growth and following the advancement. Presurgical growth was evaluated in 4 patients and postsurgical growth was evaluated in 9 patients.

RESULTS

Syndromic maxillary width and length were reduced and the most obtuse facial angles showed a lack in forward projection of the central portion in these patients. Three-dimensional distances and images superimposition demonstrated the age did not influence the course of abnormal midface growth.

CONCLUSION

The syndromic midface is hypoplastic and the sagittal deficiency is associated to axial facial concavity. The advancement performed in mixed dentition stages allowed the normalization of facial position comparable to nonsyndromic group. However, the procedure was not able to change the abnormal midface architecture and craniofacial growth.

Understanding the complexities of digital dentistry integration in high-volume dental institutions

The purpose of this article is to detail the primary challenges faced by large dental institutions as they incorporate digital dentistry into their mainstream workflow. Integration of digital technology is easier in private practices with smaller patient volumes and fewer trained staff required. Additionally, in private practices, scanning, designing and milling frequently occur in a single location, which does not require an external digital data transfer. However, large dental institutions must overcome several barriers which are uniquely generated by their large-scale operation. Numerous individuals must be comprehensively and efficiently trained to operate the advanced technologies. The digital software must seamlessly integrate with existing software and an internal infrastructure must be established capable of handling massive data inputs. High-volume production in large dental institutions requires the involvement of external laboratories to meet demand. This outsourcing presents a new challenge of safe digital data transfer in accordance with patient privacy and protection regulations set forth by governing agencies. It is vital for large dental institutions to recognise the unique challenges thrust upon them as they attempt to incorporate a digital workflow. With proper forethought and planning an appropriate infrastructure may be established allowing for a smooth and safe transition to the digital era.

The potential of additive manufacturing technologies and their processing parameters for the fabrication of all-ceramic crowns: A review

OBJECTIVE

This article aims to provide a review of the additive manufacturing technologies and the processing parameters that have been investigated for the fabrication of all ceramic crowns.

OVERVIEW

Additive manufacturing has crept its way into the field of dentistry for the fabrication of resin and metal prosthesis. To evaluate the current status of additive manufacturing for the fabrication of all ceramic crowns, literature review was targeted to include publications pertaining to the fabrication of dental ceramics and all ceramic crowns. With respect to the additive manufacturing of dental ceramics, five technologies have been investigated to date: stereolithography, material extrusion, powder based fusion, direct inkjet printing, and binder jetting. The processing parameters and experimental outcomes were collated and described for each of the aforementioned technologies.

CONCLUSION

Additive manufacturing has demonstrated promising experimental outcomes and corroborated to the fabrication all ceramic crowns. However, the technology is yet to witness a commercial breakthrough within this domain.

CLINICAL SIGNIFICANCE

Additive manufacturing mitigates raw material wastage and tooling stresses that are associated with milling of ceramics. Continued research and development can lead to its approbation as an alternate technology for manufacturing all ceramic restorations.

Effect of a Papain-based Chemomechanical Agent on Structure of Dentin and Bond Strength: An in vitro Study

Aim

To evaluate the microtensile bond strength of teeth restored with packable composite after removing caries with three chemomechanical caries removal agents (Carisolv, Papacarie and Carie-care) and also to analyze its effect on chemical composition of dentin using energy-dispersive X-ray (EDX) analysis.

Design

A total of 40 carious molars with 1 to 1.5 mm of remaining dentin were selected and divided into four groups of 20 each. Group I (control)—bur, group II—Carisolv, group III—Papacarie, group IV—Carie-care. A total of 15 samples from each group were restored with composite; 1 mm thick sections were made and were debonded under tensile load. Remaining five samples from each group were subjected to EDX for elemental analysis of dentin surface.

Results

No statistically significant difference in the bond strength values and Ca/P ratio was observed between control group and three chemomechanical agents tested in the study.

Conclusion

None of the chemomechanical agents tested in the study adversely affected the bond strength of composite resin to caries-affected dentin. Therefore, newer papain-based chemomechanical agent Carie-care can be considered as an equally effective economical alternative to commonly used agents Carisolv and Papacarie.

How to cite this article: Nair S, Nadig RR, Pai VS, Gowda Y. Effect of a Papain-based Chemomechanical Agent on Structure of Dentin and Bond Strength: An in vitro Study. Int J Clin Pediatr Dent 2018;11(3):161-166.

A Comparative Evaluation of Time-dependent Changes on the Surface Hardness of Bulk Cure Composites: An in vitro Study

Objectives

The objective of this in vitro study was to assess the surface hardness through Vickers hardness (VH) test of one conventional hybrid resin composites (Filtek Z350), compared with that of two bulk cure resin composites (SDR™, Tetric N Ceram®).

Materials and methods

Twenty specimens of each material were prepared in cylindrical aluminum molds with an internal diameter of 5 mm and depth of 4 mm, 10 (incremental curing) and 10 (bulk curing).

The surface of each specimen was covered with a transparent plastic matrix strip before light curing with conventional visible light for 40 seconds. The specimens thus obtained were stored in deionized water and transferred to an incubator at 37°C for 24 hours to simulate clinical conditions. After 24 hours, the microhardness of each specimen was measured using a Vickers indenter, with a load of 100 gm and dwell time of 15 seconds (HV 0.2/40).

The specimens were further subjected to VH test in an interval of 7, 30, and 90 days. The data were subjected to statistical analysis—Student’s t test, analysis of variance, and post hoc Tukey’s test.

Results

The present study showed that SDR™ in bulk curing showed consistently greater value of hardness and was comparable to traditional incremental cured Filtek Z350, highlighting the advantages of the new SDR technology.

How to cite this article: Sarma A, Nagar P. A Comparative Evaluation of Time-dependent Changes on the Surface Hardness of Bulk Cure Composites: An in vitro Study. Int J Clin Pediatr Dent 2018;11(3):183-187.

Accelerating Treatment of Skeletal Class II Malocclusion using Fixed Twin Block Appliances

Background

Patients with class II malocclusion generally seek orthodontic treatment for esthetic concern. Various myo-functionl appliances can be used for the treatment of skeletal as well as the dental malocclusion in a growing patient. Among various functional appliances, twin block appliance is most commonly used due to better patient compliances. It redirects the mandibular growth to correct the maxillomandibular relationship, enhancing facial esthet ics. This article presents a modified design of the twin block appliance which is less bulky, more esthetic, can be used concurrently with fixed orthodontic appliance, and is easily accepted by uncooperative patients.

Case summary

An 11-year-old-boy, who presented himself with a skeletal class II malocclusion, was treated with simultaneous use of fixed twin block along with fixed orthodontic appliance to correct both the skeletal and dental malocclusion. The twin block design was modified to have a better compatibility with the fixed orthodontic appliance.

How to cite this article: Pattanaik S, Puvvula N, Mohammad N. Accelerating Treatment of Skeletal Class II Malocclusion using Fixed Twin Block Appliances. Int J Clin Pediatr Dent 2018;11(2):146-150.

A Case of Painless Excision

Soft tissue lesions of the oral cavity are seen in children at the dental office. This case report aims to showcase the ability of laser to treat recurrent soft tissue lesions in the oral cavity in a painless manner. This painless procedure provides relief to the child and parent who suffer from anxiety toward dental treatment.

How to cite this article: Suyash IA, Bhatia R. A Case of Painless Excision. Int J Clin Pediatr Dent 2018;11(2):135-140.

Customized Hybrid Bluegrass Appliance: An Innovative Technique

Oral habits in the form of thumb sucking and tongue thrusting are commonly learned patterns of behavior seen in preschool children and they are associated with anxiety, fear, hunger, oral pressure, and sleep. Chronic practice can cause dentoalveolar, perioral problems, and atypical root resorption (ARR) of anterior primary teeth. The ARR is provoked by the thumb sucking habit, and leads to early loss of anterior primary teeth. The early loss of anterior tooth may result in speech and masticatory problems, and psychological disturbance to the child. Hence, pediatric dentists play a crucial role in giving necessary information to parents and guardians. Starting from counseling to appliance therapy, various treatment modalities have been reported in the literature. One of them is bluegrass appliance; it is a nonpunitive habit reminder therapy. The present case report describes a customized hybrid bluegrass appliance designed to eliminate thumb sucking and tongue thrusting habit, and to perform as an esthetic functional space maintainer. How to cite this article: Mohammad Z, Bagalkotkar A, Mishra A, Veerala G. Customized Hybrid Bluegrass Appliance: An Innovative Technique. Int J Clin Pediatr Dent 2018;11(2):141-145.

Comparative Evaluation of Various Temperature Changes on Stress Distribution in Class II Mesial-occlusal-distal Preparation restored with Different Restorative Materials: A Finite Element Analysis

Introduction

The principal goal of dentistry is to maintain and improve the quality of life of the dental patients. As many of these objectives require the replacement or alterations of the existing tooth structure, the main challenge for centuries has been the development and selection of biocompatible materials that can withstand the unique conditions of the oral environment.

Finite element analysis (FEA) is a modern technique of numerical stress analysis that has become a solution to the task of predicting failure due to unknown stresses by showing problem areas in a material and allowing designers to see all of theoretical stresses within.

Aims and objectives

To evaluate and compare the effect of various temperature changes on the stress distribution, in class II mesial-occlusal-distal (MOD) cavity when restored with different restorative materials, using the finite element method (FEM).

Materials and methods

Using FEA, various thermal stresses generated in class II MOD lesion using different restorative materials were studied.

Results

The computer-generated models of intact tooth and teeth restored with the different restorative materials were designed, and thermal stress at different temperatures was observed when subjected to the thermal loads of 5°C, 20°C, 36°C, and 55°C. From the results of the study, it can be concluded that glass ionomer cement (GIC) performed best, followed by intact tooth, composite resin, silver amalgam, and zinc oxide eugenol cement.

Conclusion

Restoration of class II MOD lesions with materials of lower modulus of elasticity and lower coefficient of thermal expansion will enable better stress distribution.

How to cite this article: Srivastava B, Devi NN, Gupta N, Singh R. Comparative Evaluation of Various Temperature Changes on Stress Distribution in Class II Mesial-occlusal-distal Preparation restored with Different Restorative Materials: A Finite Element Analysis. Int J Clin Pediatr Dent 2018;11(3):167-170.

Evaluation of Changes in Salivary pH after Intake of Different Eatables and Beverages in Children at Different Time Intervals

Introduction

Dissolution of the enamel in the form of erosion has increased due to shift in eating habits toward carbonated drinks like soft drink and chocolates.

Aim

The purpose of this study was to evaluate changes in the salivary pH after intake of different eatables and beverages in children at different time intervals.

Study design

Using standard salivary tests, this study was conducted as a case-control study. Fifty children between ages of 8 and 12 years having strict vegetarian diet were included in the study.

Materials and methods

Oral prophylaxis was done and salivary buffer capacity for stimulated saliva was measured. Before the saliva collection, each of the children was informed not to eat or drink anything for up to 2 hours just before the appointment.

Results

On pairwise evaluation, all the differences were found to be significant statistically except between baseline vs 30 minutes. Maximum mean difference was calculated and observed between baseline and immediately after intake of fruit juice and immediate after 30 minutes, 0.953 and 0.963 respectively, while minimum difference was calculated and observed between baseline and 30 minutes after intake of fruit juice (0.010).

Conclusion

Maximum drop was seen in cold drink when compared with fruit juice. The maximum pH increase was observed in cream biscuits with 7.63 ± 0.20. It was observed that in all the groups, the pH gradually got back to near normal levels due to the buffering mechanism of saliva.How to cite this article: Pachori A, Kambalimath H, Maran S, Niranjan B, Bhambhani G, Malhotra G. Evaluation of Changes in Salivary pH after Intake of Different Eatables and Beverages in Children at Different Time Intervals. Int J Clin Pediatr Dent 2018;11(3):177-182.

Pediatric Dental Appointments No-show: Rates and Reasons

Aim

To determine the frequency and reasons of missed and canceled pediatric dental appointments and identifying the factors associated with it among the patients visiting the pediatric dental clinic of the dental college in Navi Mumbai, Maharashtra, India. To assess the parents' perception regarding the treatment of their children and to explore the merit of different management strategies regarding the missed appointments.

Materials and methods

Self-administered questionnaires were handed over to the parents in the waiting area, whose children were undergoing treatment in the pediatric dental clinic. Questionnaire included questions pertaining to the sociodemo-graphic characteristics, methods of remembering appointments, and satisfaction with the overall past clinic experience.

Results

Of the 294 surveyed sample, 52.0% stated that they have missed an appointment. Highest percentage of the patients had missed due to parents' forgetfulness and patient's exams; 52.0% relied on their memory to remember their appointments, and 44.5% used their diaries and mobiles as a means of reminders. For canceling an appointment, most of them stated that patient was unwell and parents' commitments toward other work led to an increase in rates of no-shows. Socioeconomic status and the methods of remembering the appointment date were found to be significantly correlated with missing an appointment among the surveyed sample (p < 0.05); 48.3% said that they would want a call from the dentist a day prior to their appointment as a reminder.

Conclusion

Around one half of the patients attending the pediatric dental clinic missed their appointments. Patients most likely to fail to keep an appointment was the one who was young, remembered appointment via memory, came from a high socioeconomic class, most of them were males, and had previously broken appointments, while patients preferred receiving a call from the dentist as a reminder aide.

Clinical significance

Missing appointment creates a series of problems. Firstly, it deprives another patient the opportunity of getting treated. Secondly, it contributes to the development of long waiting list for dental services. Thirdly, it affects the patient's treatment time and may cause increase in the dental emergencies leading to a disruption in the doctor-patient relationship and behavioral management problems.How to cite this article: Bhatia R, Vora EC, Panda A. Pediatric Dental Appointments No-show: Rates and Reasons. Int J Clin Pediatr Dent 2018;11(3):171-176.

Orofacial Manifestations of Leukemic Children on Treatment: A Descriptive Study

Aim

To study the prevalence of orofacial manifestations in leukemic children undergoing treatment and to correlate these manifestations with various stages of chemotherapy.

Materials and methods

A prospective noninvasive study comprising 43 acute lymphocytic leukemic pediatric patients at various stages of therapy. They were examined on day of their each blood examination, and lesions were recorded on a self-designed pro forma. A total of 133 observations were recorded by a single observer. The treatment was divided into the phase of induction, consolidation, maintenance, and relapse.

Results

The data were analyzed using Statistical Package for the Social Sciences (SPSS) version 10.1. There were 24 males and 19 females in this study, aged between 3 and 13 years. The common oral lesions seen were dental caries, lymphadenopathy (86.04%), pallor (65.11%), ulcers (13.95%), mucositis (16.27%), gingival enlargement, hemorrhages (20.93%), candidiasis, herpes simplex virus (HSV) infection, xerostomia (44.18%), paresthesia, and tooth mobility. Herpes simplex virus infection was seen only during induction and consolidation phases. Ulcers were seen during all phases of therapy.

Clinical significance

Orofacial manifestations may be seen as the first sign of leukemia and a dentist may play a significant role in the diagnosis of the disease per se. This study highlights not only about commonly occurring lesions but also their variation during various phases of therapy. To the best of our knowledge, no study has such an extensive reporting of orofacial manifestations of acute lymphocytic leukemia (ALL) patients under treatment.

How to cite this article: Aggarwal A, Pai KM. Orofacial Manifestations of Leukemic Children on Treatment: A Descriptive Study. Int J Clin Pediatr Dent 2018;11(3):193-198.

Comparative Evaluation of Microhardness by Common Drinks on Esthetic Restorative Materials and Enamel: An in vitro Study

Aim

This study was aimed to evaluate effects of various beverages on microhardness of esthetic restorative materials.

Materials and methods

A total of 160 disk-like specimens were prepared with 40 specimens each using nanocomposite resin, nano-ionomer, compomer, and conventional composite resin as experimental groups. Forty primary teeth were prepared and mounted in acrylic to be used as control group. Microhardness of the restorative materials was measured using Vickers microhardness tester at baseline and after immersion in various beverages. The difference between the two readings was evaluated within different groups.

Results

In general, low pH beverages adversely affected the properties of the tested materials. Microhardness of tested materials was significantly decreased after immersion in various beverages with the exception of Yakult. After the immersion period, the enamel showed the maximum loss in microhardness followed by nano-ionomer.

Conclusion

Low pH beverages were the most aggressive media for enamel, nano-ionomer and compomer, but in contrast, composite resin was relatively less affected. Probiotic drink appeared relatively benign toward the tested materials.

How to cite this article: Gupta R, Madan M, Dua P, Saini S, Mangla R, Kainthla T, Dupper A. Comparative Evaluation of Microhardness by Common Drinks on Esthetic Restorative Materials and Enamel: An in vitro Study. Int J Clin Pediatr Dent 2018;11(3):155-160.

Evaluation of Dentin-Pulp Complex Response after Conservative Clinical Procedures in Primary Teeth

Introduction

Although selective caries tissue removal decreases the number and diversity of bacteria, stops the caries process, and reduces the risk of pulp exposure, the studies on the minimally removal of caries tissue are limited and further clinical research is necessary in this field.

Aim

This study aimed to evaluate through clinical and radiographic assessments the in vivo response of the dentin-pulp complex of human deciduous teeth after either partial or total caries removal (TCR).

Materials and methods

A total of 49 deciduous molars of children aged between 5 and 9 years were carefully selected. The teeth were divided into two groups: Group I: Partial removal of caries; group II: Total removal of caries. Clinical and radiographic evaluations were performed during the period of 4 to 6 months after the procedure. The intraexam-iner reproducibility was determined by Kappa test. Fisher’s exact test was used to determine the statistical difference between groups.

Results

All teeth showed clinical success during the 4- to 6-month evaluation period. The radiographic evaluation showed 94.2 and 89.6% of success rate in groups I and II respectively. Radiographic results did not show statistically significant differences between the studied groups (p > 0.05).

Conclusion

The partial caries removal (PCR) showed satisfactory clinical and radiographic outcomes, suggesting that this minimally invasive approach might replace the TCR when correctly indicated.

How to cite this article: Mello B, Stafuzza TC, Vitor L, Rios D, Silva T, Machado M, Oliveira TM. Evaluation of Dentin-Pulp Complex Response after Conservative Clinical Procedures in Primary Teeth. Int J Clin Pediatr Dent 2018;11(3):188-192.

Mandibular Regional Odontodysplasia in an 8-year-old Boy showing Teeth Disorders, Gubernaculum Tracts, and Altered Bone Fractal Pattern

Regional odontodysplasia (RO) is a rare nonhereditary developmental condition usually affecting maxilla and female patients. A few number of articles have used the cone beam computed tomography (CBCT) to describe imaging findings in RO. Thus, this article aims to report unusual imaging findings in a Brazilian child who presented with mandibular RO. A healthy 8-year-old boy was referred for evaluation of an anterior mandibular gingival enlargement. Radiographically, all right mandibular teeth showed wide pulp chambers and shortened roots with thin dentinal walls and open apices, featuring a “ghost teeth“ appearance, which indicated a diagnosis of RO. Missing teeth and altered radiopacity were observed. Cone beam computed tomography provided great insight into RO, allowing to identify gubernaculum tracts (GTs) associated with RO teeth. Fractal analysis of the bone surrounding RO teeth revealed an altered trabecular pattern.

Pre-emptive Intracoronal Radiolucency in First Permanent Molar

Pre-eruptive intracoronal radiolucency (PECR) is characterized by the existence of a radiographic radiolucent area inside the coronal dentin prior to dental eruption. It is a rare clinical entity of unknown etiology, usually asymptomatic and diagnosed through routine radiographs. The aim of this article is to report the treatment of a PECR in an 8-year-old girl. Surgical procedure to expose the crown was conducted; upon tooth eruption, the radiolucent lesion was accessed and the tooth was restored. The case has an 18-month follow-up and emphasis on aspects linked to diagnosis and clinical approach was discussed. How to cite this article: Ilha MC, Kramer PF, Ferreira SH, Ruschel HC. Pre-eruptive Intracoronal Radiolucency in First Permanent Molar. Int J Clin Pediatr Dent 2018;11(2):151-154.

Soft Tissue Changes Measured With Three-Dimensional Software Provides New Insights for Surgical Predictions

PURPOSE

Although computer-aided craniofacial reconstructions allow for simulation of hard tissue changes, the prediction of the final soft tissue facial changes remains a challenge. The purpose of the present study was to evaluate the 3-dimensional (3D) soft tissue changes in patients undergoing 2-jaw orthognathic surgery.

PATIENTS AND METHODS

For the present retrospective cohort study, 40 consecutive patients (11 men and 29 women; mean age 23.5 ± 4.9 years) who had undergone 2-jaw orthognathic surgery were selected. We obtained the medical and dental records from 3 weeks before surgery and 6 months after surgery. We used image processing software to segment, superimpose, and quantify the hard and soft tissue displacements in 3 dimensions before and after surgery at 15 paired locations. The soft tissue and hard tissue changes were determined through quantification of homologous landmark displacements between the preoperative and postoperative computed tomography data. We measured the 3D soft and hard tissue changes and the anteroposterior, inferosuperior, and transverse components of the changes. We quantified the ratios between the soft and hard tissue changes, tested Pearson's correlation between these changes, and developed a predictive regression equation for the observations at each location.

RESULTS

We found that soft tissue movement followed the hard tissue movement, with a correlation nearly equal to 0.9 (range 0.85 to 0.98), suggesting that in general the soft tissues of the maxillary and mandibular landmarks are affected similarly by the skeletal movements. The anteroposterior component of the soft tissue 3D displacements followed the hard tissue movement with a ratio greater than 0.9 and with high correlation (r > 0.9) in the mandible.

CONCLUSION

The results of the present study provide surgeons with a ratio of hard to soft tissue change and the strength of the correlations, which will allow for more accurate 3D predictions for both midline and lateral structures in bimaxillary orthognathic surgical cases. In addition, predictive equations for various landmarks were developed and can be used in computer-based prediction programs to aid in treatment planning of soft tissue changes.

Common 3-dimensional coordinate system for assessment of directional changes

INTRODUCTION

The aims of this study were to evaluate how head orientation interferes with the amounts of directional change in 3-dimensional (3D) space and to propose a method to obtain a common coordinate system using 3D surface models.

METHODS

Three-dimensional volumetric label maps were built for pretreatment (T1) and posttreatment (T2) from cone-beam computed tomography images of 30 growing subjects. Seven landmarks were labeled in all T1 and T2 volumetric label maps. Registrations of T1 and T2 images relative to the cranial base were performed, and 3D surface models were generated. All T1 surface models were moved by orienting the Frankfort horizontal, midsagittal, and transporionic planes to match the axial, sagittal, and coronal planes, respectively, at a common coordinate system in the Slicer software (open-source, version 4.3.1; http://www.slicer.org). The matrix generated for each T1 model was applied to each corresponding registered T2 surface model, obtaining a common head orientation. The 3D differences between the T1 and registered T2 models, and the amounts of directional change in each plane of the 3D space, were quantified for before and after head orientation. Two assessments were performed: (1) at 1 time point (mandibular width and length), and (2) for longitudinal changes (maxillary and mandibular differences). The differences between measurements before and after head orientation were quantified. Statistical analysis was performed by evaluating the means and standard deviations with paired t tests (mandibular width and length) and Wilcoxon tests (longitudinal changes). For 16 subjects, 2 observers working independently performed the head orientations twice with a 1-week interval between them. Intraclass correlation coefficients and the Bland-Altman method tested intraobserver and interobserver agreements of the x, y, and z coordinates for 7 landmarks.

RESULTS

The 3D differences were not affected by the head orientation. The amounts of directional change in each plane of 3D space at 1 time point were strongly influenced by head orientation. The longitudinal changes in each plane of 3D space showed differences smaller than 0.5 mm. Excellent intraobserver and interobserver repeatability and reproducibility (>99%) were observed.

CONCLUSIONS

The amount of directional change in each plane of 3D space is strongly influenced by head orientation. The proposed method of head orientation to obtain a common 3D coordinate system is reproducible.

Acquisition, Visualization and Potential Applications of 3D Data in Anatomic Pathology

Although human anatomy and histology are naturally three-dimensional (3D), commonly used diagnostic and educational tools are technologically restricted to providing two-dimensional representations (e.g. gross photography and glass slides). This limitation may be overcome by employing techniques to acquire and display 3D data, which refers to the digital information used to describe a 3D object mathematically. There are several established and experimental strategies to capture macroscopic and microscopic 3D data. In addition, recent hardware and software innovations have propelled the visualization of 3D models, including virtual and augmented reality. Accompanying these advances are novel clinical and non-clinical applications of 3D data in pathology. Medical education and research stand to benefit a great deal from utilizing 3D data as it can change our understanding of complex anatomical and histological structures. Although these technologies are yet to be adopted in routine surgical pathology, forensic pathology has embraced 3D scanning and model reconstruction. In this review, we intend to provide a general overview of the technologies and emerging applications involved with 3D data.

Comparison and reproducibility of 2 regions of reference for maxillary regional registration with cone-beam computed tomography

INTRODUCTION

The aims of this study were to evaluate the differences between 2 regions of maxillary voxel-based registration and to test the reproducibility of the registration.

METHODS

Three-dimensional models were built for before-treatment (T1) and after-treatment (T2) based on cone-beam computed tomography images from 16 growing subjects. Landmarks were labeled in all T2 models of the maxilla, and voxel-based registrations were performed independently by 2 observers at 2 times using 2 reference regions. The first region, the maxillary region, included the maxillary bone clipped inferiorly at the dentoalveolar processes, superiorly at the plane passing through the right and left orbitale points, laterally at the zygomatic processes through the orbitale point, and posteriorly at a plane passing through the distal surface of the second molars. In the second region, the palate and infrazygomatic region had different posterior and anterior limits (at the plane passing through the distal aspects of the first molars and the canines, respectively). The differences between the registration regions were measured by comparing the distances between corresponding landmarks in the T2 registered models and comparing the corresponding x, y, and z coordinates from corresponding landmarks. Statistical analysis of the differences between the T2 surface models was performed by evaluating the means and standard deviations of the distances between landmarks and by testing the agreement between coordinates from corresponding landmarks (intraclass correlation coefficient and Bland-Altman method).

RESULTS

The means of the differences between landmarks from the palate and infrazygomatic region to the maxillary region 3-dimensional surface models at T2 for all regions of reference, times of registrations, and observer combinations were smaller than 0.5 mm. The intraclass correlation coefficient and the Bland-Altman plots indicated adequate concordance.

CONCLUSIONS

The 2 regions of regional maxillary registration showed similar results and adequate intraobserver and interobserver reproducibility values.

3D Mandibular Superimposition: Comparison of Regions of Reference for Voxel-Based Registration

Introduction

The aim was to evaluate three regions of reference (Björk, Modified Björk and mandibular Body) for mandibular registration testing them in a patients’ CBCT sample.

Methods

Mandibular 3D volumetric label maps were built from CBCTs taken before (T1) and after treatment (T2) in a sample of 16 growing subjects and labeled with eight landmarks. Registrations of T1 and T2 images relative to the different regions of reference were performed, and 3D surface models were generated. Seven mandibular dimensions were measured separately for each time-point (T1 and T2) in relation to a stable reference structure (lingual cortical of symphysis), and the T2-T1 differences were calculated. These differences were compared to differences measured between the superimposed T2 (generated from different regions of reference: Björk, Modified Björk and Mandibular Body) over T1 surface models. ICC and the Bland-Altman method tested the agreement of the changes obtained by nonsuperimposition measurements from the patients’ sample, and changes between the overlapped surfaces after registration using the different regions of reference.

Results

The Björk region of reference (or mask) did work properly only in 2 of 16 patients. Evaluating the two other masks (Modified Björk and Mandibular body) on patients’ scans registration, the concordance and agreement of the changes obtained from superimpositions (registered T2 over T1) compared to results obtained from non superimposed T1 and T2 separately, indicated that Mandibular Body mask displayed more consistent results.

Conclusions

The mandibular body mask (mandible without teeth, alveolar bone, rami and condyles) is a reliable reference for 3D regional registration.