Lingual Surfaces Research Articles

Evaluating the Efficacy of Certain Intermediate Irrigants in Preventing Precipitate Formed Due to Sodium Hypochlorite and Chlorhexidine Within the Root Canal System: An In Vitro Study.

Root canal irrigation using a mixture of sodium hypochlorite (NaOCL) and chlorhexidine gluconate (CHX) might cause a precipitate to develop. This study aims to check the efficacy of sodium thiosulfate and normal saline as irrigating solutions. Roots of 45 teeth were biomechanically prepared, and the teeth were then tested.A size 15k file was introduced to the point where the apical foramen could be visible in order to provide an accurate reading of the working length. As a precaution against irrigating solutions leaking out, the specimens' tips were sealed with modeling wax before being instrumented. Each group's root canals were instrumented with #F4 hand Protaper (Dentsply Sirona, USA) as recommended by the manufacturer. Between instrumentation, The canals were lubricated with ethylenediamine tetraacetic acid (EDTA) and irrigated with 2.5% sodium hypochlorite (RC Help, Prime Dental, Mumbai, India). Fifteen samples were randomly assigned to one of three experimental categories based on the middle watering arrangement used: Group 1 (control), Group 2 (saline irrigant), and Group 3 (3.86% sodium thiosulfate). The jewel plate was submerged in water to cool it down, while two longitudinal scores were made on the root's buccal and lingual surfaces. We used a stereomicroscope to examine the exposed surfaces of the root trench in the coronal, middle, and apical thirds for the orange-earthy colored material (Stereozoom Nikon magnifying lens under 20X amplification), and we used the Mann-Whitney U test and the Kruskal Wallis test during our thorough analysis. The precipitation generated in the coronal, middle, andapical thirds had significantly different thicknesses. While precipitation did occur in all three regions, it was at a much lower rate in the apical third compared to the coronal and middle regions. In Group 1, the control group, the precipitate was thicker than in Groups 2 (saline irrigant) and 3 (3.86% sodium thiosulfate). Sodium thiosulfate, which is a biocompatible solution, can be used as an intermediate irrigant as it shows less precipitate as compared to saline.

Alveolar bone changes following bi-maxillary vertical molars’ movements using clear aligners

ObjectiveThis study aimed to assess the alveolar bone changes following maxillary and mandibular molars’ intrusion and extrusion movements using Clear Aligners using Cone-Beam Computed Tomography (CBCT).Materials and methodsThis is a retrospective clinical study in which 24 adult patients with pre-designed selection criteria and a mean age of 31.1 + 9.9 years were enrolled. The alveolar bone changes around one hundred thirty-three maxillary and mandibular molars intruded or extruded by Clear Aligners therapy were analyzed from CBCT using Invivo 6.0 software. Intra- and inter-examiner reliability analysis was performed using the intra-class correlation coefficient (ICC) and Cronbach’s Alpha statistics. The paired t-test was used to analyze significant differences before and after treatment (T0-T1). The significance level was considered at P < 0.05.ResultThe patients were divided into two groups: extrusion (48.9%, n = 65 molars’ root) and intrusion (51.1%, n = 68 molars’ root) group. There was a significant decrease in the alveolar bone changes in the buccal surface of the mandibular right and left 1st molars in the extrusion group (-1.05 ± 0.97, -0.76 ± 1.12 mm, respectively) and the maxillary left 2nd molars in intrusion group (-0.42 ± 0.77 mm), and the lingual surface of intrusion of the mandibular left 1st molar (-0.64 ± 0.76 mm). Comparing the mean maxillary and mandibular changes (T0-T1) of both studied groups showed that the buccal alveolar bone changes for the left 1st and right 2nd molars showed a significant difference in extrusion and intrusion groups, respectively.ConclusionsThe buccal alveolar bone changes is considered the most affected surface following maxillary and mandibular molars’ intrusion and extrusion movements using clear aligners, with mandibular molars being more affected than the maxillary ones.

The "sand watch" mandible.

The lingual surface of the mandible's body is commonly indicated as presenting the submandibular and sublingual fossae, which are separated by the mylohyoid line. The mylohyoid line attaches to the mylohyoid muscle (MM). Less attention has been paid to the 'mylohyoid boutonnières', which allow the 'sublingual buttons' to pass through the mylohyoid muscle in the submandibular space. The cone-beam computed tomography files of patients were routinely examined for anatomical studies. Two cases were found with unexpected morphologies of the mandible's body - the mylohyoid lines were incomplete anteriorly, and herniated sublingual tissue determined an additional fossa inferior to that line in the premolar region. That fossa was termed the 'accessory submandibular fossa'. It determined on coronal slices a 'sand watch' contour of the mandible's body. With such a peculiar morphology, the mandible is more prone to fracture. Moreover, when inserting endosseous implants, the procedure should be carefully personalised in such rare cases.

Stelladens mysteriosus: A Strange New Mosasaurid (Squamata) from the Maastrichtian (Late Cretaceous) of Morocco

Mosasaurids, a clade of specialized marine squamates, saw a major adaptive radiation in the Late Cretaceous, evolving a wide range of body sizes, shapes, and specialized tooth morphologies. The most diverse known mosasaurid faunas come from the late Maastrichtian phosphates of Morocco. Here, we report an unusual new mosasaurid, Stelladens mysteriosus, based on a partial jaw and associated tooth crowns from lower Couche III phosphatic deposits at Sidi Chennane, Oulad Abdoun Basin, Morocco. Stelladens is characterized by short, triangular tooth crowns with a series of strong, elaborate, and serrated ridges on the lingual surface of the tooth, functioning as accessory carinae. Morphology of the teeth and associated jaw fragment suggest affinities with Mosasaurinae. No close analogues to the unique tooth morphology of Stelladens are known, either extant or extinct. It may have had an unusual and highly specialized diet, a specialized prey-capture strategy, or both. The diversity of mosasaurid teeth is much higher than that of plesiosaurs, ichthyosaurs, or extant marine mammals, and likely reflects both the ecological diversity of mosasaurids and complex developmental mechanisms responsible for tooth formation in mosasaurines. Mosasaurid diversity continued to increase up to the Cretaceous–Paleogene boundary.

RESULTS OF THE USE OF 3D SCANNING IN DENTAL ANTHROPOLOGY STUDIES OF THE MODERN POPULATION

Abstract. The article describes results of using a medical intraoral scanner Medit i500 to obtain odontological information in a course of the survey of the modern population in the western regions of the Republic of Tuva within the framework of the complex ethnographic and anthropological expedition of TuvSU-CPI under the leadership of E.V. Aiyzhi. The experience of using this scanner occurred to be very successful. From a technical point of view, the scanner demonstrated high efficiency and productivity due to the high scanning speed. The use of an intraoral scanner opens up wide methodological possibilities in conducting dental anthropology studies: first, the use of digital images for further analysis instead of wax prints, makes it possible to expand the research program by including a number of features of both the lingual and vestibular surfaces of the crowns, and the occlusive one. Secondly, the researcher has the opportunity to accurately fix the sequence and degree of teething of the permanent change, which is very important for determining the correspondence of the "dental" and passport age in children, which ultimately makes it possible to assess the processes of growth and development in the population. Thirdly, it allows us to study in more detail the morphology of the teeth, more accurately assess the severity score of the dental anthropology feature. In addition, thanks to the use of the scanner, we were able to carry out an important methodological study on the analysis of interobserver agreement in the assessment of some dental traits.

Correlation of alveolar bone thickness and central incisor inclination in skeletal Class I and II malocclusions with different vertical skeletal patterns: A CBCT study

This study aimed to assess the alveolar bone thickness (ABT) and labiolingual inclination of maxillary and mandibular central incisors in patients with Class I and II skeletal patterns with normal-angle, high-angle, and low-angle vertical patterns. The study sample consisted of 200 cone-beam computed tomography scans of patients with skeletal Class I and II malocclusions. Each group was further divided into low-angle, normal-angle, and high-angle subgroups. Labiolingual inclinations of maxillary and mandibular central incisors and ABT were measured at 4 levels from the cementoenamel junction in the labial and lingual surfaces. The Kolmogorov-Smirnov test, independent t test, 2-way analysis of variance, and Spearman's correlation test were applied for statistical analyses. The only significant difference between Class I and II groups regarding the ABT was found at the labial side of the maxillary central incisor, 9 mm apical to the crest. At this level, the mean ABT was 0.87 mm in patients with a skeletal Class I malocclusion, which was significantly greater than that in patients with a skeletal Class II malocclusion with a mean ABT of 0.66 mm (P= 0.02). Comparisons among the vertical subgroups revealed that on the labial and lingual sides of the mandible, as well as the palatal side of the maxilla, significantly thinner alveolar bone was found in patients with high-angle growth patterns than those with normal-angle and low-angle patterns in both sagittal groups (P<0.05). Significant weak to moderate correlations were found between ABT and tooth inclination (P<0.05). Significant differences in ABT covering central incisors between patients with skeletal Class I and II malocclusion are merely observed at the labial surface of the maxilla, 9 mm apical to the cementoenamel junction. Compared with patients with normal-angle and low-angle, those with a high-angle growth pattern and Class I and II sagittal relationships have thinner alveolar bone support around maxillary and mandibular incisors.

Vallecular Cholesterol Granuloma: Case Report

Introduction. Cholesterol granuloma is a rare benign cystic neoplasm characterised by a fibrous capsule, and a cystic fluid containing cholesterol crystals, multinucleated giant cells, erythrocytes and haemosiderin. Cholesterol granulomas are usually found in diverse parts of the temporal bone, most commonly – petrous apex. Very few cases of cholesterol granulomas in other organs have been reported, to our knowledge none are reported in the larynx. The main purpose of this case report is to highlight this extremely rare laryngeal lesion and its unique macroscopic appearance. Case report. A 55-year-old man is referred to the Ear, Nose and Throat Centre because of persistent hoarseness, globus sensation and complicated intubation due to a mass in the larynx. Videolaryngoscopy showed a large cyst-like mass in the vallecula, epiglottis was displaced towards the posterior pharyngeal wall and erythema of interarytenoid notch and arytenoid tubercle was present. A computerized tomography scan confirmed a cystic mass on the lingual surface of the epiglottis. On the basis of the examination and clinical symptoms, a diagnosis of chronic laryngitis, gastro-oesophageal reflux and an unspecified benign tumour of the respiratory system was made, surgical treatment was planned. The patient underwent microlaryngoscopy and surgical extirpation of the cyst using a CO2 laser, as the cyst was opened a yellowish, shiny, viscous fluid was observed. Two days later, laryngoscopy revealed fibrin plaque at the site of the cyst. Final diagnosis of cholesterol granuloma was formed based on histological examination of the mass. Conclusions. Cholesterol granulomas and masses in vallecula are extremly rare, but this case shows that cholesterol granuloma can be included in the differential diagnosis of cystic neoplasms of the larynx.

Two Asian cricetodontine-like muroid rodents from the Neogene of western North America

AbstractWe appraise the morphology and potential origin of two Neogene cricetodontine-like muroids, Pliotomodon primitivus from Late Miocene sediments in northern California and an undescribed muroid from the late Oligocene or Early Miocene of central Oregon. Superficial resemblance of the dentition of Pliotomodon with members of the North American galushamyinan neotominins is considered a result of parallel evolution, as shown by the large size and unreduced M3/m3 of the former. Dental features of Pliotomodon are similar to those of Eurasian genera such as Byzantinia, Hispanomys, and Ruscinomys, but the unusual morphology of M3/m3, with continuous enamel connections across their lingual surfaces closing the hypoflexus and posteroflexid, respectively, plus retention of only three roots on M1, suggests Pliotomodon arose from an ancestor distinct from the one that gave rise to the large late Neogene hypsodont cricetodontines of the Old World. In the absence of known ancestral taxa in North America, we postulate Pliotomodon dispersed to North America across Beringia during the Hemphillian (ca. 8.6 Ma, Hh-1). Another archaic cricetodontine-like rodent, from the Warm Springs region of the John Day Formation in Oregon, is named as a new species of Deperetomys, D. dingusi new species. Deperetomys dingusi n. sp. likely descended from a species of Deperetomys intermediate between archaic species such as D. calefactus and D. magnus and more dentally derived species such as D. intermedius and D. hagni, dispersing to North America during the late Oligocene or Early Miocene (Arikareean; ca. 23 Ma, Ar3 or Ar4).UUID: http://zoobank.org/b691db3a-79de-4d3e-8af0-3bda4957b119

Transverse growth of the mandibular body in untreated children: a longitudinal CBCT study.

Currently available reports on mandibular transverse growth are limited to two-dimensional images and cross-sectional studies. The objective of this study was to examine transverse growth of the mandibular body in untreated growing individuals during the mixed dentition stage using longitudinal three-dimensional imaging. CBCT images of 25 (13 females and 12 males) untreated subjects at two time points were analyzed. The average age was 9.1years at T1 and 11.3years at T2. Mandibular segmentation and superimposition were performed to obtain linear and angular measurements at different axial levels. At the superior (mental foramen) axial level, transverse growth between the buccal surfaces gradually increased from the premolars to the ramus. At the inferior axial level, significant transverse growth differences were detected between the ramus and the dentition regions. In contrast, between the lingual surfaces, both superior and inferior levels showed minimal change in the region under the dentition and a significant amount of resorption in the ramus region. This difference between buccal and lingual surface changes led to a mandibular body angulation change in the premolar and molar regions. In contrast, the overall mandibular body angulation measured from the posterior-most border of the mandible to the symphysis remained the same. Differences were detected between males and females, with males tending to exhibit greater transverse growth in the ramus region at the inferior level. The mandibular body exhibited different transverse growth patterns at different axial levels. Differences were also found between genders. An in-depth understanding of craniofacial growth and development is crucial to diagnosis and treatment planning. The current study provides additional insight into the transverse growth of the mandible.

Management of Osteoma Peripheral Type in the Lingual of Right Lower jaw

Background: Osteoma is benign bone tumors are often found in skeletal bones. These tumors can involve any bone, but usually involve the long bones. The affected bone is generally prominent and clinically visible. This tumor is treated with surgery to remove the tumor mass. The cause of osteoma is unclear, but generally accepted theories are related to embryology, trauma, or infection. Objective: This case reports a osteoma peripheral type in the lingual of right lower jaw and and discuss according to the literature and several other similar cases. Case Report: A 37 years old man with chief complaint swelling in the posterior region right lower jaw for 16 years without pain, fever or any symptom. Case management: Panoramic radiograph and provisional diagnosis was made before surgery. Surgical excision was previously conducted under general anesthesia. Six months after surgery, the patient is in good health. Conclusion: Peripheral osteoma at the lingual surface of the right lower jaw be can be surgically treated well and do not show recurrence.

Особливості ведення пацієнтів з абсцесом надгортанника на всіх етапах медичної допомоги

An epiglottis abscess is usually the final stage of epiglottis (epiglottitis) and surrounding tissues inflammation and can progress to life-threatening airway obstruction without treatment. The etiology of the disease can be infectious or non-infectious nature. Both with infectious and non-infectious etiology, swelling of the epiglottis occurs as a result of the accumulation of inflammatory cells in the space between the layer of squamous epithelium and the epiglottis cartilage. The lingual surface of the epiglottis and peri-epiglottis tissues have a large network of lymphatic and blood vessels, which promotes the spread of infection and the subsequent inflammatory reaction. Once the infection begins, the swelling rapidly progresses, involving the entire epiglottis of the larynx (including the epiglottis folds and the epiglottis cartilages). Clinical signs of epiglottitis vary depending on age, severity, and etiology. Purpose - is to describe a clinical case of successful care for a child with an epiglottis abscess and the optimal route of the patient at all levels of medical care. Clinical case. An ambulance delivered a patient G., born in 2005 (17 years old), to the emergency otorhinolaryngology department of the Kyiv City Children’s Clinical Hospital 1. During the examination in the emergency department with indirect laryngoscopy the diagnosis was established: abscess of the epiglottis. An epiglottis abscess was urgently dissected under endotracheal anesthesia. The difficulty of diagnosing an epiglottis abscess was that visualization of the larynx is possible only with the use of instrumental examination methods, such as indirect laryngoscopy. This method is not within the competence of a family doctor. Accordingly, the family doctor, within the limits of his competencies, appropriately used the ISPS-2 international classification, section «R» - respiratory system and code - «76» and made a diagnosis of acute tonsillitis, thereby assuming the infection etiology of the disease. The family doctor, taking into account the severity of the condition, according to the patient’s itinerary, issued a referral for urgent hospitalization, according to the child's moderate condition. In our opinion, the main reason for achieving a good clinical result was an interdisciplinary approach: a combination of correctly performed diagnostics and timely surgical intervention. We hope that this clinical example, which demonstrates the features of interdisciplinary interaction between specialists, will improve the quality of medical care for patients with epiglottis abscess. The research was carried out in accordance with the principles of the Helsinki Declaration. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Comparison of Diagnostic Accuracy of 2 Cone Beam Computed Tomography System (Newtom &amp;Planmeca) for Detection of External Root Resorption in Vitro

Introduction: External root resorption is a clinical problem that is difficult to diagnose, therefore radiographic examination is important for diagnose. The purpose of this study was comparing the diagnostic accuracy of 2 Cone Beam Computed Tomography in detecting of external root resorption, in vitro.Materials &amp; Methods: This study was done on 48 single-rooted teeth. Cavities of 0.3, 0.2 and 0.15 mm in depth with round bur 0.3 mm were drilled on buccal and lingual surfaces in the cervical, middle and apical thirds of some of roots. Then CBCT were taken and 4 observers assessed the scans. Sensitivity, specificity and Kappa value were determined. The statistical analysis was performed with the Z-test (p value &lt; 0.05).Results: In comparison of the accuracy, sensitivity and specificity of the two devices, there was no significant difference. In the apical, middle and cervical as well as at various depths there was no significant difference between the two devices, but in the numerical point of view, the sensitivity for both devices in the midsection, was in the highest amount. The highest value for the specificity is related to the apical region. For both devices, the sensitivity level GBJ, by increasing the depth. The lowest agreement between observers was 0.61. The highest agreement rate was in the middle section and the least amount of agreement was related to the apical region.Conclusion: CBCT brand type is not effective factor in the detection of external root resorption. The location and depth of external root resorption can be effective factors in diagnostic accuracy.

Description and distribution of the mechanical papillae of the lingual surface of Antarctic seals species (Phocidae: Carnivora) and their relationship with diet and dental morphology

Description and distribution of the mechanical papillae of the lingual surface of Antarctic seals species (Phocidae: Carnivora) and their relationship with diet and dental morphology

Evaluation of One- and Two-Step Impression Techniques and Vertical Marginal Misfit in Fixed Prothesis.

12 impressions were made of a resin maxillary model (second premolar and second molar) with two prepared abutment teeth using vinyl polysiloxane (VPS); the margin of the second premolar was 0.5 mm subgingivally; and the margin of the second molar tooth was at the level of the gingiva. Impressions were made using two techniques: one-step and two-step putty/light materials. A three-unit metal framework was fabricated on the master model using the computer-aided design/computer-aided manufacturing (CAD/CAM) technique. The vertical marginal misfit was evaluated in the buccal, lingual, and mesial and distal surfaces of the abutments on the gypsum casts using a light microscope. Data were analyzed using the independent t-test (α < 0.05). The results showed significantly lower vertical marginal misfit in all six areas evaluated around the two abutments in the two-step impression technique compared with the corresponding values in the one-step technique. Vertical marginal misfit in the two-step technique with a preliminary putty impression was significantly lower than in the one-step putty/light-body technique.

Assessment of thin bony structures using cone-beam computed tomography.

To investigate the validity and reliability of marginal bone level measurements on cone-beam computed tomography (CBCT) images of thin bony structures using various reconstruction techniques, two image resolutions, and two viewing modes. CBCT and histologic measurements of the buccal and lingual aspects of 16 anterior mandibular teeth from 6 human specimens were compared. Multiplanar (MPR) and three-dimensional (3D) reconstructions, standard and high resolutions, and gray scale and inverted gray scale viewing modes were assessed. Validity of radiologic and histologic comparisons were highest using the standard protocol, MPR, and the inverted gray scale viewing mode (mean difference = 0.02 mm) and lowest using a high-resolution protocol and 3D-rendered images (mean difference = 1.10 mm). Mean differences were significant (P < .05) at the lingual surfaces for both reconstructions, viewing modes (MPR windows), and resolutions. Varying the reconstruction technique and viewing mode does not improve the observer's ability to visualize thin bony structures in the anterior mandibular region. The use of 3D-reconstructed images should be avoided when thin cortical borders are suspected. The small difference when using a high-resolution protocol is unjustified due to the higher radiation dose required. Previous studies have focused on technical parameters; the present study explores the next link in the imaging chain.

Evaluation of the Marginal Fit of Computer-Aided Design (CAD) and Computer-Aided Manufacturing (CAM) Zirconia Bridges Fabricated With Different Firing Cycles of Veneering Porcelain: An In Vitro Study.

Introduction Zirconia provides adequate mechanical strength to be used as a framework for all ceramic prostheses. Such prostheses must be covered with suitable porcelain to obtain good aesthetic results. The aim To study the effect of the firing cycle numbers of veneering ceramics (one cycle, two cycles, and three cycles) on the marginal fit of computer-aided design(CAD) and computer-aided manufacturing (CAM)zirconia bridges. Materials and methods The sample consisted of 30 full ceramic zirconia bridges, designed by CAD/CAM on a metal bridge model that was designed for this purpose. The sample was divided into three groups (N = 10); group Aunderwent a single firing cycle, group Bunderwent two cycles, and group Cunderwent three cycles. The copper model of the bridge was prepared to be a three-unit bridge, and the impressions of the metal models were taken to make zirconia cores. After that, the veneering ceramic layer and the micro-marginal gap were measured (in microns) on both the buccal and lingual surfaces of each bridge in the sample using the replica technique. A one-way ANOVA test was used to detect statistically significant differences between the groups. Results There were no significant differences between the studied groups in binary comparison; however, the arithmetic mean values of the marginal gap in group C were greater than all the studied groups. Conclusion Within the limitations of the current work, we found that increasing the number of firing cycles of zirconia cores affects the marginal fit; thus, it is recommended to follow the two firing cycle protocol for better adaptation of the CAD/CAM zirconia bridges.

Class II and anterior open bite malocclusion treated with mini-implants, intermaxillary elastics, speech therapy, and retained with a night-wear palatal crib wraparound

The teeth position in anterior open bite malocclusion depends on a balance of pressure between the tongue and lips and the treatment planning should include such variables. The objective of this study was to report an orthodontic case of an adult with maxillary protrusion and anterior open bite treated with skeletal anchorage and intermaxillary elastics. The patient presented a Class II malocclusion with anterior open bite, without a history of non-nutritive habits, and mandibular missing teeth at 54 years old. Mini-implants were inserted in the maxillary molars region to produce distal movement of the maxillary dentition while controlling molar extrusion, and in the mandibular anterior region on the left side to produce mesial movement of posterior teeth. Up and down intermaxillary elastics were worn in the area of the incisors to treat the open bite together with Class II intermaxillary elastics. Cleats were bonded in the lingual surface of the anterior teeth as spurs to the tongue posture. However, the best result on the anterior open bite treatment was coincident with the speech therapy. Normal relationships between the maxillary and mandibular occlusal plane of cusps, correct anterior overbite, and adequate proximal relationships were obtained at the end of treatment. The retention modality to the maxillary arch was daily wear of a removable standard wraparound and a night-time wraparound with the palatal crib. The new technology allows for more effective treatment in adults and speech therapy was helpful to achieve balanced pressure between the tongue and lips.

Macroanatomical, Histological and Microtomographic Study of the Teeth of the Komodo Dragon (Varanus komodoensis)—Adaptation to Hunting

The present study aimed to characterize the macrostructure and microstructure of the mandibular teeth of the Komodo dragon (Varanus komodoensis) and the methods it uses to obtain food. Examinations were performed using a stereoscopic microscope, autofluorescence method, histological method and computed microtomography. A detailed macro- and micro-structural description of V. komodoensis mandibular teeth were made. The mandibular teeth are laterally flattened along their entire length and the dental crown is hooked caudally. The part of the nasal margin of the tooth crown is irregular, while the caudal margin of the tooth is characteristically serrated, except for the tooth base area. There are longitudinal grooves on the lingual and vestibular surfaces up to the lower third of the tooth height. The mandibular tooth is surrounded by a cuff made of the oral mucosa, containing the opening of the venom gland. In the histological structure of the tooth, the enamel covering the tooth crown and the dentin under the enamel are distinguished. The inside of the tooth, except its basal part, is filled with the tooth chamber, while the inside of the lower part of the tooth is filled with plicidentine, which corresponds to external furrows on the enamel. The plicidentine arrangement resembles a honeycomb. A small amount of dentine folds reach up to the tooth apex. Characteristic features of the structure of the mandibular teeth in V. komodoensis may indicate their significant role, in addition to the venom glands, in obtaining food in the natural environment of this species.

A Novel 3D Volumetric Method of Analyzing Gingival Positional and Dimensional Alterations During Orthodontic Therapy: A Pilot Study.

The aim of the present study was to develop a 3D digital image-analysis method to quantitatively assess gingival changes after clear-aligner orthodontic therapy. Using teeth as fixed reference points, 3D image analysis tools have been used to quantify mucosal level changes after specific therapies. This technology has not been applied to orthodontic therapy, primarily because orthodontic tooth movement precludes using teeth as fixed reference points. Rather than superimposing the pre- and posttherapy volumes for the entire dentition, the methodology presented herein superimposed the pre- and post-therapy volumes for individual teeth. The lingual tooth surfaces, which remained unaltered, were used as fixed references. Intraoral scans taken before and after clear-aligner orthodontic therapy were imported for comparison. Volumes were created for each 3D image and were superimposed in a 3D image-analysis software that allowed quantitative measurements. The results demonstrated this technique's ability to measure very small changes in the apicocoronal position of the gingival zenith, as well as alterations of gingival margin thickness, following clear-aligner orthodontic therapy. The present 3D image-analysis method offers a useful tool for investigating the periodontal dimensional and positional changes that accompany orthodontic therapy.

The Prevalence of Mandibular Incisive Canal among a Sample of Yemeni Adults Obtained from Cone-beam Computed Tomography

Aim of this study: It was to determine the prevalence of Mandibular Incisive Canal (MIC) among a sample of Yemeni adults obtained from Cone-beam Computed Tomography (CBCT). Materials and Methods: This is a retrospective descriptive cross-sectional study which is conducted in Yemen to evaluate CBCT images of 180 subjects, 360 sides were evaluated respectively. The samples were 74 males (41.1%) and 106 females (58.9%). Result: Of the 180 subjects and 360 sides, 167 right (92.8%) and 171 left (95%) Sides were found to have MIC. Among these subjects, 166 (96.5%) had MIC bilaterally and 6 (3.5%) were unilaterally. According to gender, females were (98.1%) and males (91.9%), while among age groups ≤ 40 years (94.3%) and &gt; 40 years (97.3%) were found to have MIC. The mean height of MIC was 1.77 ±.45mm and the mean width was 1.66 ±.44 mm. The mean length of MIC was 12.74 ±4.4 mm. The mean distance from MIC to the alveolar process was 16.77 ±4.06 mm and to the inferior border of the mandible was 8.61 ±1.9 mm. The mean distance from MIC to the labial bony surface was 3.12 ±1.09 mm and to the lingual bony surface was 4.35 ±1.5 mm. All the mean values of the linear measurements were slightly higher in males than that of females. There were statistically significant differences in D3, D5 &amp; D6 between genders and in D3, D4 &amp; D5 between ages (P &lt; 0.05). But there was no statistically difference between sides. Conclusion: The MIC is present with a significant percentage of 95.6 % of Yemeni adults, which emphasizes the need to raise the awareness of MIC position and configuration among general practitioners and maxillofacial surgeons.