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Aim: The main aim of the study was to evaluate tooth position in plaster models of nonorthodontic subjects that have optimal occlusion, using the American Board of Orthodontics (ABO) criteria and comparing it to ABO standards. Methods: Forty nonorthodontic subjects with optimal occlusion were evaluated for teeth positioning with ABO measurement criteria, using the ABO gauge. These measurements were compared to the ABO standards. On the panoramic radiographs of these subjects, distances between the roots of teeth were measured using the digital ruler in Quick CephR. Lateral cephalograms were scanned and digitized into Quick CephR systems to evaluate the skeletal anteroposterior and vertical relationship. Means and standard deviations were calculated for all the variables and compared to ABO standards. Correlations were obtained between attrition and overjet. Correlations were also studied between anteroposterior skeletal relation, vertical skeletal relation, and teeth positioning. In subjects that had accurate age records, the relationship between age and change in buccolingual inclination was evaluated. Results: A significant difference in the mean values for inclination of maxillary and mandibular first bicuspids, second bicuspids, first molars, and second molars as compared to the board criteria was observed. Accuracy of panoramic radiograph to measure root proximity, especially in the cuspid region, is questionable. There was a positive correlation between overjet at the cuspid region and attrition. There was a minimal correlation between age and buccolingual inclination of teeth, indicating only a trend for mandibular second bicuspid to upright with age. Conclusion: The ABO criteria and standards used to evaluate finished orthodontic cases are consistent with naturally occurring optimal dentitions, except for buccolingual inclination of posterior teeth in both maxillary and mandibular arches. [ABSTRACT FROM AUTHOR]

Data on the age of apical closure in felines is limited. Moreover, differences in age of apical closure between male and female cats have not been studied. The aim of this study was to determine the timing of apical closure in cats and determine if sex or position in the dental arch affected closure. In this retrospective descriptive study, intraoral radiographs were obtained at monthly or multiple-monthly intervals for 18 cats. Nine were intact females and 9 were neutered males, ranging from 6 to 9.4 months of age at the start of the study which ranged over an 8-month period. Radiographs were evaluated to establish age of apical closure for all canine teeth as well as the mandibular premolar and molar teeth. Mandibular canine tooth apices closed between 10 and 12 months of age and maxillary canine tooth apices closed between 12 and 14 months of age. The mesial and distal root apices of both the mandibular third and fourth premolar teeth closed between 8 and 9 months. The mandibular first molar tooth mesial and distal root apices closed between 8 and 8.5 months. Root apices of canine teeth closed earlier in female cats than in male cats with mandibular canine tooth root apices closing significantly earlier than maxillary canine tooth roots in both sexes. These findings suggest that there are notable differences in age of apical closure between male and female cats and discernible trends in timing of apical closure among teeth in the dental arcade. [ABSTRACT FROM AUTHOR]

Macrophages are important regulators of bone remodeling, and M1 polarization is observed in the setting of medication-related osteonecrosis of the jaws (MRONJ). Here, we characterize the phenotype of macrophages during early stages of MRONJ development in zoledronate (ZA)–treated mice with periodontal disease and explore the role of rosiglitazone, a drug that has been reported to lower the M1/M2 macrophage ratio, in MRONJ burden. Mice received ZA, and experimental periodontal disease (EPD) was induced around their second left maxillary molar. The mice were euthanized 1, 2, or 4 wk later. Micro–computed tomography and histologic and immunohistochemical analyses were carried out. In a separate experiment, mice were treated with ZA in the absence or presence of rosiglitazone, EPD was induced for 5 wk, and the MRONJ burden was assessed. An M1 predilection was noted in ZA versus vehicle (Veh) mice at 1, 2, or 4 wk after ligature placement. M1 cells were found to be positive for MMP-13, and their presence coincided with disruption of the surrounding collagen network in ZA mice. Rosiglitazone caused a reversal in the M1/M2 polarization in Veh and ZA mice. Rosiglitazone did not cause significant radiographic changes 5 wk after EPD in Veh or ZA animals. Importantly, percentage osteonecrosis and bone exposure were decreased in the rosiglitazone-treated versus nontreated ZA sites 5 wk after EPD. Our data point to an important role of M1 macrophage polarization with an overexpression of MMP-13 in the early phases of MRONJ development and provide insight into the use of interventional approaches promoting an M2 phenotype as a preventative means to alleviate MRONJ burden. [ABSTRACT FROM AUTHOR]

Intact extraction of the mandibular first molar tooth is an interesting model for studies of alveolar bone healing. The aim of this study was to describe a new experimental technique for extraction of rat mandibular first molar teeth with crown and all 4 roots intact using controlled forces applied to the teeth. One hundred and twenty female Sprague-Dawley rats were used from a center for experimental animal research. Animals underwent general anesthesia and were then placed in a special dental unit (designed by Moghadam) for the extraction of rat teeth. After syndesmotomy, luxation of the tooth began with a tipping movement in the buccal direction with a very low range of motion for 1 s. A tipping movement in the lingual direction was then used to continue luxation. After a maximum of 10 repetitions, the tooth was left alone for 30 s. After 3-4 stages of this cycle, the tooth loosened. To complete the luxation, the same forces were applied in the buccal and lingual directions with larger amplitude for 3 s. After this step, the tooth was loose enough to be easily extracted. The alveolus was then sutured closed. The results showed no hemorrhage or fracture of crowns and mesial or distal roots, and only 8% of the buccal and lingual roots fractured. The technique designed and used in this study was shown to be an effective model for complete molar tooth extraction in the rat. This technique could also be used in the treatment of other rodents. [ABSTRACT FROM AUTHOR]

Introduction: Skeletal anchorage devices for the efficient orthodontic treatment mechanics can be placed at various interradicular and extraradicular sites intra orally. However, their placement in the infrazygomatic crest area can broaden the horizon of orthodontic treatment. The bone thickness in the infrazygomatic crest (IZC) area can vary at different heights and insertion angles during the placement of IZC screws between maxillary second premolar and second molar region. Aims and objectives: The purpose of our study was to evaluate the variation in bone thickness in the IZC area at different insertion angles along the mesiobuccal root of maxillary first molar and at different heights from the crest of the alveolar bone in the apical direction between maxillary second premolar and second molar region using cone beam computed tomography, so as to determine the best possible site where the bone thickness will be maximum that will suit to a particular size of IZC screw. Materials and Methods: CBCT images of 50 subjects were analyzed by a single observer, the bone thickness in the IZC area was measured and interpreted at different heights from the alveolar crest in the apical direction, that is, 5 mm, 7 mm, 9 mm, 11 mm at six regions between maxillary second premolar and second molar. Bone thickness was also measured at different insertion angles ranging from 55º to 75º to occlusal plane of permanent maxillary first molar along its mesiobuccal root. Results: The bone thickness in the IZC area was 4.5 mm-3.5 mm, when it was measured at different angles ranging from 55º to 75º to the occlusal plane of maxillary first molar along its mesiobuccal root with maximum bone thickness at 75° with a mean ± SD of 4.56 ± 1.4. Statistically significant differences in bone thickness were found between maxillary first and second molar on both right and left sides at different heights with maximum bone thickness at 11 mm apical from the alveolar crest with a mean ± SD of 2.03 ± 0.76 and 1.91 ± 0.88, respectively, and along the mesial root of maxillary second molar on right and left sides at 11 mm apical from the alveolar crest with a mean ± SD of 2.12 ± 0.80 and 1.95 ± 0.75, respectively. Conclusions: The best site and safe zone for miniscrew insertion in IZC area is at 7 mm to 9 mm distance from the alveolar crest apically along the mesial root of maxillary second molar and at an angle of 55°-75º to the occlusal plane of maxillary first molar, so as to ensure the adequate stability of the miniscrew and without causing any damage to the adjacent anatomical structures. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate and correlate the maturation stage of the midpalatal suture, CVM stages, mandibular left second molar mineralization stages of the subjects by CBCT. Materials and Methods: One hundred subjects (55 males and 45 females) with a mean age of 13.56 ± 4.46 years, were divided into five midpalatal suture maturational stage groups (A to E). Cervical vertebral maturational stages on lateral cephalograms and second molar mineralization stages on orthopantograms from the CBCT images obtained from Carestream CS 9300C 3D system were analyzed and correlation among them were calculated by Spearman's coefficient of correlation and midpalatal suture maturation stage prediction accuracy estimated with sensitivity, specificity, positive predictive value, and likelihood ratio. Results: Spearman's correlation analysis showed a highly significant (p value < .001) and positive correlation between MPS stage and CVM Stage (r = 0.930), MPS stage and mandibular left second molar mineralization stage (r = 0.757), and CVM stage and mandibular left second molar mineralization stage (r = 0.760). Conclusion: Cervical vertebral maturation stages 1,2, and 3 can be used clinically to predict the midpalatal suture maturation stages A, B, and C, respectively, as their likelihood ratios were more than 10. Second molar mineralization stages had less predictive value for MPS stages. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this report was to assess the skeletal, dental and soft tissue changes in a juvenile patient with a severe class III malocclusion. This case report describes a novel method of class III treatment using skeletal anchorage for maxillary protraction and Alt-RAMEC protocol. Patient concerns: The patient did not have any subjective complaints before treatment and there was no family history of class III malocclusion. Clinical findings and primary diagnoses: Extra-orally, the patient had a concave profile with a retrusive mid-face and prominent lower lip. The intra-oral examination revealed angle class III malocclusion with a −3-mm overjet. There was no anterior displacement on closure when the patient was assessed clinically. According to the cephalometric analysis, the sagittal jaw relation and Wits appraisal were reduced due to a retrognathic maxilla and prognathic mandible. Interventions: The treatment plan involved maxillary protraction, Alt-RAMEC protocol for 10 weeks and upper molar distalisation with a hybrid hyrax distalizer in combination with a mentoplate. The active treatment time was estimated to 18 months followed by 6 months retention with the appliance. Outcomes: The sagittal jaw relationship was increased by approximately 9°, mainly due to maxillary advancement of 8 mm and a positional change of the mandible anteroposteriorly. Natural decompensation of the lower incisors was also observed. In addition, both the facial profile and the smile became more harmonious after treatment. The treatment analysis revealed that the changes achieved were mainly skeletal and it was possible to avoid adverse effects on the dentition. Conclusion: In conclusion, treatment with a hybrid hyrax distalizer combined with mentoplate using the Alt-RAMEC protocol is effective in correcting the anteroposterior discrepancy in a juvenile class III patient and it is possible to achieve maxillary advancement of 8 mm. [ABSTRACT FROM AUTHOR]

Introduction: The aim of these four case reports was to illustrate the presence of potential upper second molar impactions associated with ectopic third molars and to highlight that some cases have an atypical radiographic presentation. Case presentations: Four patients (age range = 7–12 years) with various malocclusions presented to the paediatric and orthodontic departments for treatment to address their presenting complaints. Incidental radiographic findings demonstrated potentially impacted upper second molars associated with ectopic third molars. In all of these cases, a joint paediatric-orthodontic approach was adopted to address their dental health, prevent upper second molar impaction and to treat their malocclusion. Discussion: Careful and systematic review of radiographic imaging was necessary in order to diagnose these cases correctly. These cases demonstrated that it was not always simple to determine impactions, particularly as identification of third molar crypts can be difficult. On occasion, sequential radiographic monitoring is advocated, particularly in patients in the mixed dentition; however, clinicians must be mindful of the risks of ionising radiation as it is not routine practice to irradiate a patient multiple times. Conclusion: The series of cases highlights the need for a systematic assessment of OPTs to identify ectopic upper third molars. The input from radiologists is invaluable and if necessary, supplemental three-dimensional cone-beam computed tomography can be performed. [ABSTRACT FROM AUTHOR]

This document provides abstracts of research articles related to dentistry. The first abstract compares the success rates of two techniques, SMART and conventional drill and fill, in restoring carious lesions in primary molars. The study found no significant difference in success rates, but SMART was better accepted by children. The second abstract discusses regenerative endodontics and minimally invasive dentistry as emerging concepts to preserve tooth structure and promote regeneration. The third abstract focuses on outcome assessment methods for bioactive and biodegradable materials used in pulpotomy procedures. The study calls for the development of predictable outcome measures. The final abstract reviews the effect of non-surgical periodontal therapy on HbA1c levels in periodontitis patients without diabetes, showing a significant decrease after therapy. The document also includes articles on the relationship between diabetes and periodontal/peri-implant disease, the acceptability of the WISP instrument for symptom assessment in cancer patients, risk prediction models for oral cancer, and the clinical outcomes of the posterior Dahl concept for treating posterior tooth wear. [Extracted from the article]

Analyses of National Health and Nutrition Examination Survey (NHANES) data suggested a significant decrease in sealant prevalence among children between 2011 to 2014 and 2015 to 2018. We explore whether this decrease could be associated with possible changes in 1) clinical sealant delivery, 2) dental materials (i.e., increased use of glass ionomer [GI] sealants resulting in an inability to detect sealant fragments that still provide preventive benefits or increased use of composite restorations leading to misclassifying sealants as restorations), and 3) examination sensitivity and specificity. We used NHANES data to estimate the prevalences of sealants, untreated caries, and restorations in ≥1 first permanent molar among children aged 7 to 10 y and used Medical Expenditure Panel Survey data to estimate the annual clinical delivery of sealants and fluoride treatments. We examined changes in outcomes between 2 periods (P < 0.05) controlling for selected sociodemographic characteristics. NHANES sealant examination quality was based on the reference examiner's replicate examinations. The adjusted prevalence of sealants decreased relatively by 27.5% (46.6% vs. 33.8%). Overall, untreated caries decreased. Untreated caries and restoration decreased among children without sealants. Annual clinical sealant delivery did not change, whereas fluoride treatment delivery increased. The decrease in sealant prevalence held when assessed for various age ranges and NHANES cycle combinations. While sealant examination specificity remained similar between the periods, sensitivity (weighted by the proportion of exams by each examiner) decreased relatively by 17.4% (0.92 vs. 0.76). These findings suggest that decreased sealant prevalence was not supported by decreased clinical sealant delivery nor increased use of composite restorations. Decreased examination sensitivity, which could be due to an increased use of GI sealants, could contribute to the decrease in sealant prevalence. The decrease in caries among children without sealants could suggest the increased use of GI sealants. However, we could not rule out that the decrease in caries could be attributable to increased fluoride treatment delivery. [ABSTRACT FROM AUTHOR]

Objective: This study assesses the degree of root curvature in patients with non-syndromic cleft lip and/or palate (NSCL/P). Design: Retrospective. Case-control study. Setting: Root curvature was assessed in lower premolars and molars in 800 panoramic radiographs: 400 from patients with cleft and 400 from healthy control individuals. Root curvature was classified according to its angulation, as well as its apical, medial, or coronal localization. Results: The frequency of mild curvature in the NSCL/P group compared to the control group was higher in premolars especially in the left second premolar in cleft palate (OR: 6.91; 95% CI: 3.23−14.77; P <.0001). The frequency of moderate curvature in molars was significantly higher in the cleft group, with the highest risk in the right first molar in the cleft lip group (OR: 2.74; 95% CI: 1.67−4.52; P <.0001). Inclination was more frequently observed in the apical third of the root in the group with cleft, whereas for the control group, the curvature was more frequent in the medial third. In patients with cleft, the OR of curvature in the apical third was significant in premolars (left lower second premolar: Cleft lip, OR: 1.91; 95% CI: 1.04−3.52; P =.03; right lower second premolar: Cleft lip, OR: 1.91, 95% CI: 1.04−3.50; P =.03, cleft lip and palate, OR: 1.75; 95% CI: 1.12−2.73; P =.01). Conclusion: The results of the current study indicate differences in root curvature in patients with non-syndromic cleft lip and/or palate, which should be considered during the dental treatment planning of patients. [ABSTRACT FROM AUTHOR]

Objective: The primary aim of this study was to provide a review of the types and frequency of orthodontic brackets, molar bands and orthodontic auxiliaries used for patients undergoing orthognathic surgery. The secondary aim was to evaluate the risk of failure of these items during orthognathic surgery. Methods: From three Dutch hospitals, 124 adult patients were included in this prospective cohort study. Five independent researchers collected the data during surgery using a specifically created data extraction form. The type of surgery, surgeon, orthodontist and type of orthodontic bracket, molar band or auxiliary were noted for each tooth. To evaluate their failure risk, the following variables were noted: failure and site; and type and cause of failure. Results: Stainless-steel brackets were the most frequently (75.8%) used bracket type seen in patients undergoing orthognathic surgery. Ceramic brackets were seen in 24.2% of the cases and were only applied in the anterior region. Molar bands were present in 58.9% of the patients and mostly with bands on the first molars in combination with bonded tubes on the second molars. In 32.2% of all cases, one or more failures were noted. One-third of all failures were described as detachment of the molar tube on the most posterior molar. Kobayashi ligatures and powerpins showed the highest risk of failure (odds ratio [OR] 3.70, 95% confidence interval [CI] = 1.91–7.15). No significant difference in failure rate was found between stainless-steel brackets, molar bands (OR 0.34, 95% CI = 0.08–1.43) and ceramic brackets (OR 0.44, 95% CI = 0.14–1.45). Conclusion: Stainless-steel brackets, ceramic brackets, molar bands and surgical hooks are suitable for orthognathic cases. Kobayashi ligatures and powerpins had a significantly higher risk of failure so are not recommended for temporary intraoperative maxillomandibular fixation (TIO-MMF). [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of different CAD/CAM materials and occlusal thicknesses on the fracture resistance of primary molar crowns. Methods: Sixty extracted primary molar teeth were prepared and randomly divided into six experimental groups according to the material and thickness. Primary molar crowns with a central groove thickness of 0.3 and 0.5 mm were fabricated from CAD/CAM zirconia (group Z), zirconia-reinforced lithium silicate (group ZLS), and pre-polymerized composite resin blocks (group C). Each crown was cemented with self-adhesive resin cement on the prepared tooth. All specimens were subjected to fracture tests until fracture. Fracture load values were recorded in Newtons (N). Data were statistically analyzed using a two-way analysis of variance (ANOVA) followed by Tukey multiple comparison test. Results: The highest fracture load values were obtained in group Z at 0.5 mm occlusal thickness and were significantly higher compared with the other experimental groups (p < 0.05). Although the lowest fracture load values were obtained in group ZLS at 0.3 mm occlusal thickness, all the tested CAD/CAM primary molar crowns at both thicknesses demonstrated fracture load values exceeding reported chewing force in pediatric patients. Conclusion: CAD/CAM primary molar crowns with reduced occlusal thickness may be used for the full-coverage restoration of primary molar teeth. [ABSTRACT FROM AUTHOR]

To compare two methods of maxillary molar distalisation with skeletal anchorage using finite element analysis (FEA). Two digitised models were created: the miniscrew-anchored distaliser, which consisted of a distalisation method anchored in a buccal miniscrew between the first molar and second premolar (Model 1), and the miniscrew-anchored palatal appliance, which consisted of a distalisation method anchored in a miniscrew on the anterior region of the palate (Model 2). FEA was used to simulate both methods, assessing teeth displacements and stress concentration. The miniscrew-anchored distaliser showed greater buccal than distal displacement of the first molar, while the opposite was observed in the miniscrew-anchored palatal appliance. The second molar responded similarly in the transverse and anteroposterior perspectives with both appliances. Greater displacements were observed at crown level than in apical regions. Greater stress concentration was observed at the buccal and cervical regions of the crown in the miniscrew-anchored distaliser and the palatal and cervical regions in the palatal appliance. The stress progressively spread in the buccal side of the alveolar bone for the miniscrew-anchored distaliser and in the palatal root and alveolar bone for the palatal appliance. FEA assumes that both appliances would promote maxillary molar distalisation. A skeletally anchored palatal distalisation force seems to provide a greater molar bodily movement with less undesirable effects. Greater stress is expected at the crown and cervical regions during distalisation, and the stress concentration in the roots and alveolar bone depends directly on the region the force was applied. [ABSTRACT FROM AUTHOR]

Implant restoration is currently the most mainstream method for repairing missing teeth. With the increasing number of plantings, various planting complications begin to be paid attention to. Among them, there are many reports of disability phenomena such as loose and broken abutment screws and broken top screws, which cause the implant to fail or fail to function. In recent years, with the development of computer-aided software and its application in the field of oral treatment, digital guide plates based on 3D printing of oral CBCT scanning data are widely used in oral implants. Therefore, we explore the application prospect of post-core crown restoration after removing broken screws from the implant abutment with a digital guide plate. We reported a case of upper right first molar implant abutment screws broken, which were removed by a digital guide plate and customized turning bur. The resin-matrix ceramics crown post core was prepared, and then the occlusal force was tested by the T-ScanIII system. It provides a reference for the application of digital guide plates in special cases such as broken screws of implant abutment. [ABSTRACT FROM AUTHOR]

Class II malocclusion is one of the most commonly seen malocclusions in the orthodontic practice, with a variety of treatment modalities found in the literature. Maxillary molar distalization is a one of treatment options of dental Class II patients with excessive overjet, anterior crowding, or both. However, a commonly seen side effect in the conventional distalization devices is anchor loss. Here, in this case report, we have shown the successful treatment of a Class II malocclusion patient with a new concept of modified placement of the hybrid hyrax appliance, which was used effectively for en-masse, bodily distalization of maxillary teeth, with no anchorage loss. Also, the same appliance could be used for retention after the active distalization period till the treatment completion. [ABSTRACT FROM AUTHOR]

B ABSTRACT b B Purpose b To assess the mechanical performance and enamel-crack propensity of large MOD composite-resin restorations on maxillary molars with severely undermined cusps. Fracture modes for specimens bonded without rubber dam isolation were adhesive and cohesive within enamel, while rubber dam experimental groups revealed only cohesive fractures. A filled three-step etch-and-rinse adhesive performed superiorly, with or without rubber dam isolation, when bonding to enamel compared to an isopropanol-based universal adhesive. B Material and methods b In total, 88 bovine enamel samples (7 × 8 × 4mm; n = 8) were submitted to the ceramic laminate veneer luting protocol according to surface treatment (unbleached and bleached enamel), antioxidant agents (control; 10% ascorbic acid and 10% -tocopherol), and luting periods (after 24h and after 14 days). [Extracted from the article]

Objective: This study investigates crown and root anomalies in patients with Parry-Romberg Syndrome. Design: This is a retrospective review of patients with Parry-Romberg Syndrome who were evaluated at a tertiary care center from 1980-2020. Setting: Patients seen in the dental unit from 1980-2020. Patients, Participants: Seventeen patients with documented Parry-Romberg Syndrome were referred for dental evaluation. Main Outcome Measures: All dental anomalies were documented. Root anomalies were assessed using panoramic radiographs and cone beam CT (CBCT) scans to evaluate buccal-lingual, mesio-distal, and axial measurements of hypoplastic teeth, which were compared to those of contralateral teeth. Results: Findings included agenesis (29%, n = 5), hypoplastic teeth (29%, n = 5), delayed canine eruption (24%, n = 4), and mulberry molars (12%, n = 2). Of the five patients with tooth hypoplasia, four had CBCT records and the fifth had panoramic radiographs available for assessment. Axial length was always shorter in hypoplastic teeth relative to contralateral teeth, with differences ranging from 1.2-9.2 mm. Differences in crown size of hypoplastic versus contralateral teeth were unpredictable but always present. Conclusions: Patients with Parry-Romberg Syndrome can have hypoplastic roots with atypical crown morphology. A patient's specific dental anomaly will influence planning and treatment. [ABSTRACT FROM AUTHOR]

The relationship between oral health and the development of Alzheimer's disease (AD) in the elderly is not yet well understood. In this regard, the association between aging or neurodegeneration of the trigeminal nervous system and the accumulation of amyloid-β(1–42) (Aβ42) oligomers in the pathogenesis of AD is unknown. We focused on selective autophagy in the trigeminal mesencephalic nucleus (Vmes) and the diffusion of Aβ42 oligomers with respect to aging of the trigeminal nervous system and whether the degeneration of Vmes neurons affects the diffusion of Aβ42 oligomers. We used female 2- to 8-mo-old transgenic 3xTg-AD mice and App NL-G-F knock-in mice and immunohistochemically examined aging-related changes in selective autophagy and Aβ42 oligomer processing in the Vmes, which exhibits high amyloid-β (Aβ) expression. We induced degeneration of Vmes neurons by extracting the maxillary molars and examined the changes in Aβ42 oligomer kinetics. Autophagosome-like membranes, which stained positive for Aβ, HO-1, and LC3B, were observed in Vmes neurons of 3xTg-AD mice, while there was weak immunoreactivity of the membranes for intraneuronal Aβ in App NL-G-F mice. By contrast, there was strong immunopositivity for extracellular Aβ42 oligomers with the formation of Aβ42 oligomer clusters in App NL-G-F mice. The expression of Rubicon, which indicates age-related deterioration of autophagy, increased the diffusion of Aβ42 oligomer with the age of Vmes neurons. Tooth extraction increased the extracellular immunopositivity for Aβ42 oligomers in App NL-G-F mice. These results suggest that autophagy maintains homeostasis in Vmes neurons and that deterioration of autophagy due to aging or neurodegeneration leads to the diffusion of Aβ42 oligomers into the extracellular space and possibly the development of AD. [ABSTRACT FROM AUTHOR]

An increasing number of clinicians have been utilising orthodontic mini-screws as temporary anchorage devices (TAD) in their practices, but variable successful rates have been reported. Here, we introduce a practical approach to inserting mini-screws successfully. Using computer-aided design (CAD) and computer-aided manufacturing (CAM) technology, the surgical guide for pre-drilling was designed and fabricated and mini-screws were placed following pre-drilling holes in two cases. Two Ø2.0 × 10.0-mm mini-screws were inserted into the prepared holes in the mandibular buccal shelf (MBS) on both sides with a hand driver to distalise the lower molars for Class III correction. The treatment was done successfully, after 12 months of treatment in one case. Two Ø1.6 × 8.0-mm mini-screws were inserted into the prepared holes in the mandibular alveolar process in another case with congenital absence of lower right second premolar. One mini-screw was in the buccal alveolar process between the mandibular right canine and first premolar and the other in the lingual alveolar process between the mandibular right first premolar and second primary molar. The lower right molars would be protracted to close the space left after the extraction of the primary molar using the two mini-screws. The case was still in treatment. [ABSTRACT FROM AUTHOR]

Rapid palatal expansion has been associated with significant short and long term unwanted effects such as dentoalveolar tipping and detrimental periodontal effects when carried out in skeletally mature individuals. Mini implant assisted rapid palatal expansion (MARPE) has proven to reduce the undesirable effects seen in tooth supported expanders and allows expansion even in adults. A variety of designs have been suggested with their pros and cons. Biomechanically, it is important that the TADs attachment of the expansion appliance should be as close to the palatal vault as possible. This prevents bending of TADs and allows for a better split by keeping forces closer to the bone. According to the T zone concept given by Benedict Wilmes, the bone in the canine-premolar region is much superior for TAD insertion and stability as compared to the bone in the molar region. Considering all the above features a new MARPE appliance was designed which is versatile, anatomically compatible and easy to use. FAVEX is a treatment-centric appliance so that the treatment need not be appliance centric. [ABSTRACT FROM AUTHOR]

Aim and Objective: The aim of the study was to compare the full-depth bone thickness and the cortical bone thickness in the infrazygomatic crest (IZC) region above the mesiobuccal (MB) root of maxillary first molar and second molar and thus find the ideal site for the placement of IZC screw. Materials and Methods: Pretreatment cone-beam computed tomography images of 30 orthodontic patients were collected and IZC bone thickness and cortical bone thickness were measured above the MB root of maxillary first and second molar at an angle of 70° to the molar occlusal plane. Measurements were done on both right and left sides. Independent sample t test was done to compare the bone thickness between the right and left sides and also to compare the bone thickness above the first and the second molar. Results: Mean bone thickness at the IZC region of 5.48 ± 2.2 mm and 7.78 ± 2.35 mm and a cortical bone thickness of 2.24 ± 0.46 mm and 2.13 ± 0.46 mm was obtained above the MB root of maxillary first molar and second molar, respectively. IZC bone thickness was significantly higher above the second molar than above the first molar (P <.001), whereas there was no significant difference in the cortical bone thickness measured on both the sites (P =.22). Conclusion: Significantly higher IZC bone thickness was noted above the MB root of the maxillary second molar, which may ensure better stability and safety of the miniscrew. [ABSTRACT FROM AUTHOR]

Implant restoration is currently the most mainstream method for repairing missing teeth. With the increasing number of plantings, various planting complications begin to be paid attention to. Among them, there are many reports of disability phenomena such as loose and broken abutment screws and broken top screws, which cause the implant to fail or fail to function. In recent years, with the development of computer-aided software and its application in the field of oral treatment, digital guide plates based on 3D printing of oral CBCT scanning data are widely used in oral implants. Therefore, we explore the application prospect of post-core crown restoration after removing broken screws from the implant abutment with a digital guide plate. We reported a case of upper right first molar implant abutment screws broken, which were removed by a digital guide plate and customized turning bur. The resin-matrix ceramics crown post core was prepared, and then the occlusal force was tested by the T-ScanIII system. It provides a reference for the application of digital guide plates in special cases such as broken screws of implant abutment. [ABSTRACT FROM AUTHOR]

Skeletal anchorage systems have been used for intrusion of the posterior teeth with satisfactory results. To achieve this, mini-implants are placed at anatomically challenging sites such as the palate or require several mini-implants to produce the desired effect. To determine the magnitude of intrusion of the maxillary posterior teeth achieved on a continuous arch wire using a single buccal mini-implant placed bilaterally in young patients with a tendency towards hyperdivergence and to evaluate its influence on the skeletal, dental and soft-tissue structures. A total of 17 patients with proclination of the anterior teeth, tendency towards hyperdivergence and clockwise rotation of the mandible were selected. First premolars were extracted as part of treatment protocol. A 0.022-MBT bracket prescription was used. Mini-implants were placed bilaterally on the buccal aspect at the mucogingival junction or slightly gingival to it between the maxillary second premolar and first permanent molar. A total of 200 g of intrusive force was placed from a continuous 0.019 × 0.025 inch stainless-steel arch wire to the mini-implant by means of an elastomeric thread on both sides. Lateral cephalograms and study models were taken before the start of intrusion and six months later. Parametric and non-parametric tests were done to assess treatment results. Significant intrusion was observed in the maxillary molar and premolar region with tendency towards intrusion in the anterior region. There was significant decrease in lower anterior facial height (LAFH) with anti-clockwise mandibular rotation, decrease in facial proportion index and total facial height. No changes were observed in the transverse plane. Intrusion of the permanent maxillary molar can be achieved on a continuous arch wire with a single buccal mini-implant placed bilaterally with improvement in facial aesthetics, especially in the vertical plane. This method may be beneficial in patients with borderline vertical discrepancy treated with conventional friction mechanics during space closure after first premolar extractions. [ABSTRACT FROM AUTHOR]

Dental pain is a persistent, detrimental public health issue that requires a better understanding of the mechanisms of tooth pain and inflammation in order to develop more effective treatments. Calcitonin gene-related peptide (CGRP) and dental pulp cells are promising candidates for mediating tooth pain and generating reparative dental tissues, respectively, but their behavior in the context of pulpitis remains elusive. The mouse incisor requires Sonic hedgehog (Shh) secreted from sensory nerves to continuously regenerate. However, it is unknown whether sensory nerves also regulate the comparatively nonregenerative mouse molar through CGRP and Shh. This is an important knowledge gap to fill since mouse incisors differ biologically from human teeth, while mouse and human molars are similar. In this work, we identified that molar pulp cells express CGRP receptor and Gli1, a Hedgehog (Hh) signaling protein found to label a dental stem cell population in the mouse incisor. We also observed in a mouse molar injury model that Hh signaling was activated and Shh expression was upregulated in vivo. We then determined in vitro that Shh and CGRP regulate differentiation of primary mouse molar and incisor pulp cells and a human dental pulp stem cell line. Furthermore, conditioned media from stimulated sensory neurons induced Hh signaling activation and inflammatory gene expression in primary molar pulp cells, which was abolished by inhibition of either Shh or CGRP. Our results suggest that CGRP and Shh signaling may promote an inflammatory response after injury in the molar and that activated sensory nerves secrete CGRP and Shh to regulate molar pulp cell expansion and differentiation into odontoblast-like cells for dentin repair. Thus, CGRP/Shh signaling should be considered for new strategies that seek to manage pain or dentin regeneration in the molar. [ABSTRACT FROM AUTHOR]

Tooth agenesis is a common structural birth defect in humans that results from failure of morphogenesis during early tooth development. The homeobox transcription factor Msx1 and the canonical Wnt signaling pathway are essential for "bud to cap" morphogenesis and are causal factors for tooth agenesis. Our recent study suggested that Msx1 regulates Wnt signaling during early tooth development by suppressing the expression of Dkk2 and Sfrp2 in the tooth bud mesenchyme, and it demonstrated partial rescue of Msx1 -deficient molar teeth by a combination of DKK inhibition and genetic inactivation of SFRPs. In this study, we found that Sostdc1/Wise, another secreted Wnt antagonist, is involved in regulating the odontogenic pathway downstream of Msx1. Whereas Sostdc1 expression in the developing tooth germ was not increased in Msx1 −/− embryos, genetic inactivation of Sostdc1 rescued maxillary molar, but not mandibular molar, morphogenesis in Msx1 −/− mice with full penetrance. Since the Msx1 −/−; Sostdc1 −/− embryos exhibited ectopic Dkk2 expression in the developing dental mesenchyme, similar to Msx1 −/− embryos, we generated and analyzed tooth development in Msx1 −/−; Dkk2 −/− double and Msx1 −/−; Dkk2 −/−; Sostdc1 −/− triple mutant mice. The Msx1 −/−; Dkk2 −/− double mutants showed rescued maxillary molar morphogenesis at high penetrance, with a small percentage also exhibiting mandibular molars that transitioned to the cap stage. Furthermore, tooth development was rescued in the maxillary and mandibular molars, with full penetrance, in the Msx1 −/−; Dkk2 −/−; Sostdc1 −/− mice. Together, these data reveal 1) that a key role of Msx1 in driving tooth development through the bud-to-cap transition is to control the expression of Dkk2 and 2) that modulation of Wnt signaling activity by Dkk2 and Sostdc1 plays a crucial role in the Msx1-dependent odontogenic pathway during early tooth morphogenesis. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the treatment outcomes between Twin Block and AdvanSync2® appliances by comparing the skeletal, dentoalveolar, and soft tissue changes. Materials and Methods: Radiographic data of 20 patients were retrospectively analyzed. Data were selected from patients in their skeletal growth spurt as evaluated by the cervical vertebral maturation method (CVMI 2, 3, and 4), with class II malocclusion characterized with retrognathic mandible (ANB > 4°, SNB < 77°, FMA = 25 ± 5°, overjet > 5 mm). There were 10 patients in each group that underwent orthodontic correction for class II malocclusion: either using Twin Block or AdvanSync2®. Independent t test and Paired t test and chi-square tests were used for the data analysis. The level of statistical significance was set at P value =.05. Results: The chronological and skeletal age were similar in both the groups. Records were taken for the functional treatment with mean treatment span of 8 ± 1 month. Changes in SNB (group I = 1.59°, group II = 3.11°) (P < .01), Co-Gn (group I = 2.89 mm, group II = 5.34 mm), and U1-L1° (group I = -1.51°, group II = 2.97°) showed statistically different outcome between the groups, when the pre-post data were studied. Rest of the variables--cranial base, maxillary skeletal, mandibular skeletal, intermaxillary, vertical skeletal, maxillary dentoalveolar, mandibular dentoalveolar, and soft tissue--showed similar outcome (P > .05). Conclusion: Both appliances lead to desirable outcomes in the correction of class II malocclusion. AdvanSync2® resulted in inducing more of changes in SNB and effective mandibular length as compared to Twin Block. Overjet and molar relation improved significantly with both the appliances. Both the appliances resulted in similar skeletal, dentoalveolar, and soft tissue changes. [ABSTRACT FROM AUTHOR]

This study aims to assess the contributory and predisposing effects of prolonged drought and climate phenomena on the occurrence of dental abnormalities among three age groups of the black duiker (Cephalophus niger). 36 skulls comprised of 18 females and 18 males were examined. Each group consisted of 8 kids (age range 0-10 months) (4 males and 4 females), 14 mature individuals (age range 1-3 years) (7 males and 7 females) and 14 adults (age range older than 3½ years) (7 males and 7 females). It was observed that the most severe defects occurred in mature and old females during prolonged drought. Morphologic disruptions of the dentition occurred more frequently on the mandible relative to the maxilla. 93% showed apical dental aberration. Bone resorption occurred in 30% and 6% of females and males respectively with profile aberrations at both time stages, tooth staining was observed in 40% of females and 8% of males, attrition accounted for 15% in each of both sexes, 28% and 3% of the females and the males had missing teeth respectively with more occurrence in the premolars and the molar teeth. Calculus was found in 4% and 9% of the females and males respectively. These findings may be useful in determination of likely age and season for occurrence of dental pathologies, in evaluation of response to irrigation and may provide information to assist in bioremediation of dental pathology. [ABSTRACT FROM AUTHOR]

The furcation is the anatomic area where the roots divide on a multirooted tooth. Periodontal disease causing alveolar bone loss can lead to furcation lesions of various stages. Once furcation involvement has occurred, the area can be more difficult to clean or treat due to the complex anatomy and morphology of furcations. Teeth with short root trunks, longer tooth roots, and roots with wide furcation entrance areas/degrees of separation and wide root divergence are considered better candidates for long term maintenance. Dog teeth possess many of these advantageous anatomic features compared to human teeth. Treatment options for teeth with furcation lesions include: closed debridement, open debridement, furcation plasty, tunneling, partial tooth or root resection, root separation (hemisection or trisection), regenerative therapies, or exodontia. There are many factors to consider in determining treatment options. The favorable and unfavorable characteristics for maintenance of teeth with furcation lesions are summarized. Home care and ongoing professional care are important aspects of periodontal disease control for any patient. Studies of systemic and local antibiotic therapies in human patients have not demonstrated reduction of furcation stages, and probiotic effects at furcation sites have not been specifically examined. Human review studies show that most molar teeth once deemed "hopeless" due to stage 3 furcation lesions can be maintained for at least 5 to 15 years with supportive periodontal therapy. Similar long term studies in dogs are needed to improve the evidence-based management of canine patients with furcation lesions. [ABSTRACT FROM AUTHOR]

This study was performed to report etiology, clinical presentation, and outcome of mandibular fractures in immature dogs treated with non-invasive or minimally invasive techniques. Immature dogs diagnosed with mandibular fractures from 2001 to 2016 were included in this study. Diagnosis of the mandibular fracture was achieved by oral examination and diagnostic imaging in the anesthetized dog. Twenty-nine immature dogs with 54 mandibular fractures were selected. Within the mandibular body, the regions of the developing permanent canine and first molar teeth were most commonly involved (46.4% and 35.0%, respectively). Within the mandibular ramus, 53.8% of the fractures were located in its ventral half, and 38.5% in the condylar process. Muzzling was applied in 72.4% of the dogs. All dogs had clinical healing with resolution of signs of pain and recovery of mandibular function. Mean time for clinical healing was 21 ± 9 days. Age of the dog and duration of muzzling were significantly associated with the time needed for clinical healing. In immature dogs, fractures of the mandibular body occur most commonly in the regions of the developing permanent canine and first molar teeth, while fractures of the mandibular ramus are most commonly found in its ventral half and the condylar process. Non-invasive or minimally invasive management of mandibular fractures in immature dogs carries a good prognosis regarding clinical healing and recovery of mandibular function. Dogs should be monitored for the development of dental abnormalities and/or skeletal malocclusion until permanent teeth have erupted and jaw growth is completed. [ABSTRACT FROM AUTHOR]

B Conclusion: b DANA can reduce the growth, the biofilm formation and the virulence of I P. gingivalis i and exhibits anti-inflammatory effects, as well as effects against rat periodontitis, suggesting that DANA should be considered for development as a new adjunctive treatment for periodontitis. The effect of DANA on I P. gingivalis i -induced periodontitis in rats was analyzed by radiography, stereoscopic microscopy, histopathology, and immunohistochemistry. B Yu S, Fan X, Zheng S, et al. b I The sialidase inhibitor, DANA, reduces Porphyromonas gingivalis pathogenicity and exerts anti-inflammatory effects: An in vitro and in vivo experiment. 2021;92(2):286-297 i B Background: b Sialidase has an important role in the pathogenesis of periodontitis and I Porphyromonas gingivalis i is a sialidase-producing organism implicated in periodontitis development. [Extracted from the article]

This case report describes a simple alternative for treatment of mesioangulation of mandibular second molars. An 11-year-old girl was diagnosed with unilateral posterior crossbite, moderate incisor crowding and mesioangulation of the right mandibular second molar. The ectopic second molar was uprighted using a modified lingual arch with a distal hook and elastic chains. Orthodontic traction began after appliance installation and was activated once per month using 120 g of force. After six months, the right mandibular second molar was in an upright position. Orthodontic treatment continued with teeth levelling and alignment until acceptable occlusal and aesthetic results were achieved. Adequate stability was observed one year after debonding. The modified mandibular lingual arch with a distal hook is a simple and effective alternative to manage mesioangulation of mandibular second molars with minimum adverse effects and stable outcomes. [ABSTRACT FROM AUTHOR]

Temporomandibular joint (TMJ) disorder caused by occlusal trauma is one of the most controversial topics in dentistry. Experimental traumatic occlusion (ETO) induced by metal crowns cemented to mandibular first molars in rats causes a long-lasting nociceptive response. This study aimed to elucidate whether ETO generates an increase in inflammatory mediators in the TMJ. In addition, the impact of ETO on trigeminal ganglia, neurotransmitter release, and satellite glial cell (SGC) activation was investigated. ELISA revealed enhanced inflammatory mediators, including TNF-α, IL-1β, IL-6, CX3CL1, and ADAM-17 by Western blotting, in periarticular TMJ tissue after 28 d of ETO. In the trigeminal ganglia, ETO groups increased the release of the neurotransmitters substance P and glutamate. Overexpression of the AMPA receptor and upregulation of NMDA were observed in the 0.4- and 0.7-mm ETO groups, respectively, highlighting enhanced neuronal excitation. Increased IL-1β and COX-2 mRNA levels in the 0.7-mm ETO group confirmed trigeminal ganglia SGC activation. Immunofluorescence and electrophoresis of SGC revealed increased pERK expression in the 0.7-mm ETO group. ERK phosphorylation was shown to be nociceptive specific, with its upregulation occurring in cases of chronic inflammatory pain. Increased PKA mRNA levels were observed in the 0.4-mm ETO group, while CREB mRNA levels were upregulated for both ETO groups. Electrophoresis showed overexpression of sodium channel Nav 1.7 in the 0.7-mm ETO group, while immunofluorescence revealed that Nav 1.7 is expressed in sensory trigeminal ganglia cells. The results of this study suggest that occlusal trauma induces neuroimmune crosstalk, with synthesis of proinflammatory/pronociceptive mediators, which increases neuronal activity in trigeminal ganglia via the activation of an inflammatory response cascade to develop a persistent neuroinflammatory state that leads to central sensitization. [ABSTRACT FROM AUTHOR]

Objective: To compare dental arch relationship outcomes following 3 different 2-stage palatal repair protocols. Design: Retrospective, cross sectional. Setting: Three cleft palate centers (A, B, C) in Japan. Patients: Ninety (A: 39, B: 26, C: 25) consecutively treated Japanese patients with complete unilateral cleft lip and palate. Interventions: In A, the soft palate and the posterior half of the hard palate were repaired at a mean age of 1 year 7 months. In B, the soft palate and hard palate were closed separately at a mean age of 1 year 6 months and 5 years 8 months, respectively. In C, the soft palate and hard palate were closed at a mean age of 1 year and 1 year 5 months, respectively. Main Outcome Measures: Dental arch relationships were assessed using the 5-Year-Olds' (5-Y) index by 5 raters and the Huddart/Bodenham (HB) index by 2 raters. Results: Intra- and inter-rater reliabilities showed substantial or almost perfect agreement for the 5-Y and HB ratings. No significant differences in mean values and distributions of 5-Y scores were found among the 3 centers. The mean HB index scores of molars on the minor segment were significantly smaller in C than those in A and B (P <.05). Conclusions: There were no significant differences in dental arch relationships at 5 years among the times and techniques of hard palate closure. However, further analysis of the possible influence of infant cleft size as a covariable on a larger sample size is needed. [ABSTRACT FROM AUTHOR]

Within this subsection is a link to the articles, an MCQ test and a link for the CPD certificate. The Journal of Orthodontics is pleased to provide the readership with the opportunity to obtain Enhanced Continuing Professional Development (CPD). The MCQ test must be completed and passed before clicking on the CPD certificate link to generate the certificate. [Extracted from the article]

Introduction: Correction of Class II has become a routine with the introduction of mini-implants. Objective: The objective of the study was to evaluate the clinical efficiency of bone-anchored intraoral bodily molar distalizer (BAIBMD) as compared to bone-anchored pendulum appliance (BAPA). Materials and Methods: This split-mouth study included 11 subjects (6 boys and 5 girls) who required molar distalization. BAPA constructed on one side and BAIBMD on the other side. Both the appliances were anchored to the bone, using a single 2 × 8 mm titanium mini-screw placed in the anterior para-median region of the mid-palatal suture with its head embedded into the Nance button during construction. The force delivery mechanism on both the sides consisted of 200 g-force application, using an activated 0.032˝ titanium molybdenum alloy (TMA) springs fabricated with respective designs and inserted into the lingual sheaths of the first molar bands. The rate, duration, and nature of tooth movement for both the sides were compared. Descriptive statistics for various parameters were analyzed using Wilcoxon signed-rank test. Results: Clinically successful distalization was achieved on both sides. No statistical difference was found in the rate of distalization. Differences in the treatment duration between the two groups were statistically significant, with less duration taken for distalization with BAPA. Statistically significant molar tipping was observed in BAPA. Conclusion: While both the appliances provided a similar rate of distalization, BAIBMD took more duration than BAPA but produced a predominantly translatory type of distal tooth movement. [ABSTRACT FROM AUTHOR]

Oral surgery and exodontia can present challenges in veterinary patients, with a particular area of challenge being extraction and closure of the maxillary first molar (M1) in dogs. This retrospective assessment evaluated patients that had the maxillary first molar extracted with placement of a cruciate suture across the alveolus to achieve partial closure and secure the blood clot. Patients that had teeth extracted adjacent to M1 (maxillary fourth premolar [PM4] or second molar [M2]) were excluded from the study. Three groups of patients were assessed: Group A – at the time of extraction of M1, both the maxillary PM4 and M2 were still present in the oral cavity. Group B – at the time of M1extraction only PM4 or M2 was present, but not both. The tissue was completely intact at the location of the missing tooth. Group C – at the time of M1 extraction neither PM4 or M2 were present, but tissue in these locations was intact. In a three-and-a half-year time period (2015-2018), 179 dogs with 213 solitary M1 extractions were performed. Of these 213 extraction sites, 127 sites (60%) had follow up examination within a two-week postoperative period. Of these 127 sites, 126 (99.2%) appeared appropriately healed without complication. The results of this retrospective evaluation demonstrate that primary closure of a maxillary first molar extraction site may not be required for appropriate soft tissue wound healing in canine patients. [ABSTRACT FROM AUTHOR]

To evaluate the gingival condition due to adult orthodontic treatment using the clinical crown height (CCH) as an index. Retrospective study. Department of Orthodontics at a university. A total of 21 adult female patients with healthy periodontal tissue were treated by means of the multi-bracket appliance with extraction of four first premolars. Three-dimensional (3D) digital dental models were reconstructed to assess the vertical movement of the free gingival margin caused by adult orthodontic treatment. Pre- and post-treatment CCH were measured, and changes in CCH due to treatment were examined. The change in CCH by orthodontic treatment was able to be assessed objectively using 3D digital models of the dental casts. In the upper dentition, a significant reduction in CCH was found on the labial and lingual sides of the central incisor, with a mean of –0.28 mm and –0.34 mm, respectively (P < 0.001). In contrast, a significant increase in CCH was found on the labial side of the lateral incisor with a mean of 0.75 mm (P < 0.001). In the lower dentition, CCH on the lingual side of the canine, the second premolar and the first molar increased significantly (P < 0.001), with a mean of 0.41 mm, 0.45 mm and 0.50 mm, respectively. For the buccal side, the second premolar showed a significant increase in CCH with a mean of 0.61 mm (P < 0.001). By using the CCH as an index, it was possible to assess the gingival condition after active orthodontic treatment. [ABSTRACT FROM AUTHOR]

Introduction: The primary concern in the placement of ramal bone screws is the blind nature of the procedure, as there is a thick, mobile layer of soft tissue over the bone; also, the ramus is not a uniplanar structure but is swerving like a propeller blade. The purpose of this study was to evaluate the possibility of establishing clinical guidelines based on visible dental and soft-tissue landmarks for safe, reliable, and accurate insertion of ramal bone screws. Aims and Objectives: Our primary objective was to evaluate the angle formed between the appropriate direction of ramal-implant placement and the line tangential to the buccal surfaces of the first and second permanent molars. Our secondary objective was to evaluate the average distance of the neurovascular bundle from the tip of the bone screw. Materials and Methods: We obtained 80 cone beam computed tomography (CBCT) samples, marked reference lines and points on selected axial and coronal sections, and evaluated the following parameters using the software's linear- and angularmeasurement device: the angle between the appropriate direction of ramal bone screw placement and the line tangential to the buccal surfaces of the first and second permanent molars; and the proximity of the bone screw to the neurovascular bundle. Results: The angle between the constructed line of insertion and the occlusal line, as evaluated from our study, was 19.04 (SD ± 6.89) degrees. The proximity of the neurovascular bundle from the screw is 7.1773 (SD ± 1.73988) mm. Conclusion: We can conclude that ramal bone screws can be placed with a comfortable margin of safety. [ABSTRACT FROM AUTHOR]

To investigate the effect of angulation of permanent mandibular second molars (MM2) on eruption problems and investigate a new method of measuring MM2 angulation for the diagnosis and evaluation of delayed tooth eruption (DTE) for easy use in dental practice. Retrospective study. Department of Orthodontics, Necmettin Erbakan University. A total of 98 patients aged 9–18 years. Patients with 64 permanent MM2s with delayed eruption problems were included in the study group. The control group consisted of patients with 83 normally erupted teeth. In addition, a sub-group, consisting of 23 patients showing unilaterally delayed eruption of the same teeth, was set as a split-mouth group. All patients with unilateral delayed eruption of second molar teeth were selected from the study group to form the sub-group. Angulations of permanent MM2s were measured on panoramic radiographs with two measurement methods: (1) a new method; and (2) a previously accepted method. The comparison of the study and control groups was performed by Mann–Whitney U-test and the split-mouth group was analysed with the paired t-test. The P value was set at 0.05 for statistical significance. Measurements of the tooth angulation values of the study group were significantly higher than in the control group for both measurement methods (P < 0.001). In addition, in the split-mouth group, angulation values of delayed eruption side were significantly higher than the erupted side (P < 0.001). Increased angulations of permanent MM2s could be associated with delayed eruption problems of these teeth. This new method could be useful in clinical dentistry to determine the eruption evaluation of lower second molars. [ABSTRACT FROM AUTHOR]

The prophylactic removal of asymptomatic third molars is a common but controversial procedure often rationalized as necessary to prevent future disease on adjacent teeth. Our objective in this retrospective cohort study of adult men was to examine whether second-molar loss differed by baseline status of the adjacent third molar, taking into account the individual's overall state of oral hygiene, caries, and periodontitis. We analyzed data from participants of the VA Dental Longitudinal Study who had at least 1 second molar present at baseline and 2 or more triennial dental examinations between 1969 and 2007. We classified second molars by third-molar status in the same quadrant: unerupted, erupted, or absent. Tooth loss and alveolar bone loss were confirmed radiographically. Caries and restorations, calculus, and probing depth were assessed on each tooth. We estimated the hazards of second-molar loss with proportional hazards regression models for correlated data, controlling for age, smoking, education, absence of the first molar, and whole-mouth indices of calculus, caries, and periodontitis. The analysis included 966 men and 3024 second molar/first molar pairs. Follow-up was 22 ± 11 y (median 24, range 3–38 y). At baseline, 163 third molars were unerupted, 990 were erupted, and 1871 were absent. The prevalence of periodontitis on the second molars did not differ by third-molar status. The prevalence of distal caries was highest on the second molars adjacent to the erupted third molars and lowest on the second molars adjacent to the unerupted third molars. Relative to the absent third molars, adjusted hazards of loss of second molars were not significantly increased for those adjacent to erupted (hazard ratio [HR] = 0.96, 95% confidence interval [CI] = 0.79–1.16) or unerupted (HR = 1.25, 95% CI = 0.91–1.73) third molars. We found similar results when using alveolar bone loss as the periodontitis indicator. Our findings suggest that retained third molars are not associated with an increased risk of second-molar loss in adult men. [ABSTRACT FROM AUTHOR]

The article presents a case of a 45-year-old woman who was presented to a hospital due to occlusal pain in her right first molar of the mandible to discuss a rare case of intraosseous schwannoma of the mandible masquerading as radicular cyst of the molar. Her lesion was diagnosed as radicular cyst and underwent surgery to remove her right first molar and cyst under general anesthesia. Other topics include the differential diagnosis for radiolucent lesion of the jaws.

This case series is a follow-up report focusing on dental and facial characteristics in patients with a rare microdeletion in chromosome 14q22.1-q22.2. Usually, these patients have severe ocular, brain, and digital abnormalities. However, this case series shows that clinical presentation can be mild. Four relatives spanning 3 generations were diagnosed with a familial autosomal dominant 2.79 Mb microdeletion in chromosome 14q22.1-q22.2. Genetic screening was done by the Bacterial Artificial Chromosome array-comparative genome hybridization and was confirmed by the fluorescence in situ hybridization technique. Dental and craniofacial data were collected from medical files, clinical examinations, clinical photos, panoramic and cephalometric radiographs, and dental casts. Written informed consent for scientific use was obtained for all family members. No larger syndrome could be identified. All cases had similar facial red flag characteristics, consisting of a long face with retrognathia and open mouth relation, associated oral clefts in varying degrees, depressed nasal bridge, delayed tooth development, hypertelorism, and low-set angular ears. The dental casts showed a distal molar occlusion and a lack of space in the dental arches. Developmental delay was noted together with limb defects such as poly- and syndactyly. Microphthalmia and hearing loss were present in the most severe cases. This rare congenital disorder, associated with facial dysmorphia, oral clefts, and tooth agenesis, can remain undiagnosed until adulthood. A family history of short stature, developmental delay, poly- or syndactyly, and micropthalmia are suggestive features. Similar reports help to raise awareness among dental practitioners, leading to an early genetic diagnosis. [ABSTRACT FROM AUTHOR]

A 14-year-old American Paint Horse mare was referred for further evaluation of a firm mass with an associated draining tract at the base of the left ear suspected to be a dentigerous cyst. Approximately three months prior, the draining tract had been excised under the presumed diagnosis of an abscess with no improvement. Physical examination revealed a firm mass palpable at the base of the left ear with a draining tract that did not elicit any pain response on palpation. Digital radiographs revealed a 6x11cm mineral mass in the left temporal region. Medially, there were two projections that extended into the left temporal bone. Cone beam computed tomography (CT) showed mild thinning of the temporal bone separating the mass and the brain at the conical extension of the caudal aspect of the mass. Both structures were isolated and elevated using a combination of osteotomes, mallet, and bone rongeurs under general inhalant anesthesia with radiographs to determine complete removal. Although histopathology was declined, gross examination of both structures resembled adult molar teeth. At eight months postoperative, the owners reported that the surgical site was healed and no discharge was present. Dentigerous cysts should remain a differential for a mass with an associated draining tract at the base of the ear in horses. Practitioners should strongly consider CT when feasible for additional diagnostics in similar cases. Although benign and removal poses risk, dentigerous cysts can be surgically excised with a positive outcome. [ABSTRACT FROM AUTHOR]

The adult patients requiring orthodontic treatment usually need adjunctive dental care for complete rehabilitation. There are so many orthodontic appliances that are used as retainer after comprehensive treatment to retain the orthodontic tooth movement achieved. The purpose of this clinical pearl is to showcase a modified acrylic retainer to prevent the supra-eruption of terminal molar whose antagonist tooth was to be replaced using dental implant after the completion of orthodontic treatment. [ABSTRACT FROM AUTHOR]

Antemortem domestic pig (Sus scrofa domesticus) dental pathology literature is sparse. This observational descriptive study evaluated 23 client-owned pigs that while sedated/anesthetized for routine annual care had intraoral dental radiographs and an oral examination performed. Age, gender, weight, and breed for each pig were recorded. Oral examination and radiographic findings were reviewed to create a comprehensive list of dental abnormalities identified. Descriptive statistics were performed to summarize the data. The study population included 14 castrated males and 20 Vietnamese pot-bellied mini-pigs. The median age was 3 years (range 2-12 years), and the median weight was 39 kg (range 11-140 kg). The most common finding was missing teeth (21/23 pigs); the first premolar tooth was the most likely to be absent (64/106 missing teeth). Periodontal disease was common (20/23 pigs). Advanced stages primarily affected the first molar teeth frequently in the form of a mucogingival defect. Supernumerary roots were discovered on the maxillary canine teeth in female pigs only (10/25 teeth with supernumerary roots). The most common persistent deciduous tooth was the maxillary second incisor (15/19 persistent deciduous teeth). Non-age or gender related open apices were most likely associated with mandibular first and second incisor teeth (26/96 teeth with open apices). Tooth resorption was also identified (7/23 pigs). The study findings prove that pet pigs commonly have dental pathology; therefore, thorough oral examinations with intraoral radiographs should be included in porcine routine health care regimens. [ABSTRACT FROM AUTHOR]

To interpret a correlation between buccolingual inclination of molars and palatal depth in hyperdivergent patients and to identify importance of determining inclination of molars in assessing transverse discrepancies (as skeletal or dental) This was a retrospective cone beam computed tomography (CBCT) study. The study was conducted in the Department of Orthodontics, Saveetha Dental College and Hospital, Tamil Nadu, India. This was a retrospective CBCT study of 79 patients who underwent diagnostic CBCT for treatment purposes. The CBCT scans were evaluated systematically and the required parameters were accessed with suitable reference planes. Student's t-test (95% confidence interval) was performed to determine buccolingual inclination of first molars between the right and left sides. Only patients with a vertical growth pattern and skeletal class I relation were included and they were classified into three groups based on their palate depth. In patients with palatal depth > 22 mm, the mean inclination of molars was 7.4°; with palatal depth in the range of 19–22 mm, the mean inclination of molars was 5.23°; and with palatal depth < 19 mm, the mean inclination of molars was 2.9°. Results showed that there was a significant correlation between the buccolingual inclination of molars and the palate depth in vertical growers (P < 0.05). The buccolingual inclination of first molars is increased in patients with greater palatal depth. This parameter is helpful in classifying crossbites as skeletal or dental. The amount of compensation required to correct the cross bite can be adjusted using Korkhaus Index. [ABSTRACT FROM AUTHOR]

Uprighting molar that is mesially angulated improves its periodontal status, coupled with bone deposition at the distal surface. It also provides adequate support to its occlusal antagonist and maintains a stable occlusal pattern. Various methods for uprighting molars using springs, nickel-titanium superelastic wires, and miniscrews have been elucidated in literature. This article presents a modification of spring fabricated of nickel-titanium that is effective in uprighting mesially angulated molars with minimal invasiveness. The proposed advantage of using this spring was that buccal flaring of the angulated molar was not observed due to the mild distalizing force applied against the molar by the tugging action of the spring. [ABSTRACT FROM AUTHOR]