Search

The present study investigated the osseointegration of dental implants with a titanium plasma-sprayed surface (TPS) in regenerated and native bone in an experimental dog study. Initially, lateral bone defects were created in the alveolar ridge on both sides of the mandible. Two months later, lateral ridge augmentation was performed with (1) autogenous corticocancellous block grafts, (2) autogenous corticocancellous block grafts and e-PTFE membrane, (3) tricalcium phosphate particles and e-PTFE membrane, or (4) canine-derived demineralized freeze-dried bone allograft particles and e-PTFE membrane. After 4 months, membranes were removed, and non-submerged titanium implants were placed in regenerated bone (test implants) and in native bone (control implants). Two months later, the animals were sacrificed and non-decalcified orofacial sections were evaluated histometrically. All implants demonstrated high percentages (59% to 75%) of bone-to-implant contact, with no significant differences across the various treatment groups. The different grafting techniques did not significantly influence the location of first bone-to-implant contact and the horizontal bone width at the most coronal bone level. [ABSTRACT FROM AUTHOR]

Displacement injuries of permanent teeth are an increasing emergency in the dental office. Children and adolescents are particularly prone to dental trauma due to participation in risky activities. Repositioning or replantation with subsequent stabilization by a dental splint is the standard of care for most displaced or avulsed permanent teeth. Non-rigid fixation allowing physiologic tooth mobility has been shown to be desirable for periodontal healing. A flexible splint of short duration appears to reduce the risk of dentoalveolar ankylosis or external replacement resorption. Different splinting techniques are currently recommended for stabilization of repositioned or replanted teeth, including a wire-composite splint, an orthodontic bracket splint or a resin splint. Each splinting option has its specific advantages and shortcomings. This paper describes a new splinting technique which offers improved comfort and handling to the patient and dentist alike. [ABSTRACT FROM AUTHOR]

Ankylosis of traumatized teeth in children and adolescents may inhibit further development and growth of the corresponding jawbone. Therefore, ankylosed teeth should be removed. As an alternative treatment option to autotransplantation of a premolar, intentional replantation using Emdogain may be considered, provided the ankylosis is detected at an early stage or has only affected a small area of the root. Eleven ankylosed teeth presenting with replacement resorption were treated as follows: after tooth extraction, the root canal was treated extraorally and obturated by retrograde insertion of a titanium post. Emdogain was applied to the root surface and into the extraction socket with subsequent replantation of the tooth. During a mean follow-up period of 6.3 months, no signs of recurrence of ankylosis were noted. The horizontally and vertically measured Periotest scores were identical to those obtained on the adjacent teeth. These results suggest that intentional replantation using Emdogain may prevent or delay ankylosis of these replanted teeth. [ABSTRACT FROM AUTHOR]

A 12-year-old patient sustained avulsions of both permanent maxillary central incisors. Subsequently, both teeth developed replacement resorption. The left incisor was extracted alio loco. The right incisor was treated by decoronation (removal of crown and pulp, but preservation of the root substance). Comparison of both sites demonstrated complete preservation of the height and width of the alveolar bone at the decoronation site, whereas the tooth extraction site showed considerable bone loss. In addition, some vertical bone apposition was found on top of the decoronated root. Decoronation is a simple and safe surgical procedure for preservation of alveolar bone prior to implant placement. It must be considered as a treatment option for teeth affected by replacement resorption if tooth transplantation is not feasible. [ABSTRACT FROM AUTHOR]

Rapid measurements of vibrational linear dichroism (VLD) infrared spectra are shown to be possible by using stretched polymer films and an extension of existing instrumentation designed for vibrational circular dichroism spectroscopy. Earlier techniques can be extended using additional inexpensive polymer substrates to record good-quality VLD spectra of a significantly wider range of compounds with comparatively short sample-preparation times. The polymer substrates used, polyethylene and polytetrafluoroethylene, are commonly available and inexpensive, and samples are more easily prepared than that for many earlier stretched-film and crystal studies. Data are presented for neutral hydrophobic organic molecules on hydrophobic films including acridine, anthracene, fluorene, and recently synthesized S -(4-((4-cyanophenyl)ethynyl)phenyl)ethanethioate. We extend the approach to polar or ionic species, including 2,2'-bipyridine, 1,10-phenanthroline, and sodium dodecyl sulfate, by oxidizing polyethylene films to change their wetting properties. The combination of new instrumentation and modified sample preparation methods is useful in basic spectroscopy for untangling and assigning complicated infrared spectra. Nevertheless, it is not a panacea as surface-adsorbed molecules are often not monodispersed, and higher analyte concentrations can lead to aggregation and resonance phenomena that have previously been observed for infrared spectra on surfaces. These effects can be assessed by varying the sample concentration. The focus of this paper is experimental, and detailed analysis of most of the spectra lies outside its scope, including some well-studied compounds such as acridine and anthracene that allow comparisons with earlier research., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Angina bullosa haemorrhagica (ABH; also: bullosa haemorrhagica oralis or "benign hemorrhagic bullous stomatitis") was first defined by Badham in 1967 as recurrent formation of blood blisters on the oropharyngeal mucosa as a result of mechanically traumatic irri- tation. A possible connection with previous damage to the mucosa due to general medical findings such as hypertension, diabetes mellitus or chronic inhalation of corticosteroids has not yet been confirmed.

One of the most frequent pathologies of jaw bone is a bacteria-induced inflammation at the apices of teeth with subsequent bone resorption that typically presents as a radiolucency in radiographs. Usually, corresponding clinical and radiographic findings correlate and allow for an accurate diagnosis. However, occasionally an unexpected and completely different diagnosis presents as documented in this case report. In a 55-year-old female patient, a radicular cyst was suspected in her right maxillary bone. The treatment plan included a cystectomy as well as apical surgery of the adjacent and root-canal filled teeth 15 and 16. However, the intraoperative finding absolutely did not fit a radicular cyst but rather a mucous retention cyst, as could be confirmed subsequently by histopathology. The diagnosis of a mucous retention cyst within the jaw bone is extraordinary and as such has never been described before in the literature.

Purpose: The aim of this study was to evaluate the prevalence of clinically relevant anatomical variations of the ethmoid sinuses and their potential association with ethmoid and maxillary sinus pathologies on cone-beam computed tomography (CBCT) scans. Additionally, potential associations with different sides and demographic factors, including age and sex, were evaluated., Materials and Methods: In total, 273 CBCT scans with complete ethmoid and maxillary sinuses were analyzed to determine the prevalence of Agger nasi cell, supraorbital ethmoid cell, Haller cell, Onodi cell, and ethmomaxillary sinus. In addition, the health or pathology of the ethmoid and maxillary sinuses was also recorded to assess correlations with the aforementioned variations., Results: The prevalence of Agger nasi cell was found to be the highest (95.6%) in this study, followed by Onodi cell (60.4%), Haller cell (29.3%), and supraorbital ethmoid cell (19.4%). Ethmomaxillary sinus was the least common finding (16.5%). Males and persons above 61 years of age had a significantly higher frequency of supraorbital ethmoid cell and Onodi cell, respectively. However, no significant relationships were noted between anatomical variations of the ethmoid sinus and pathologies of the ethmoid or maxillary sinus., Conclusion: There was a high prevalence of ethmoid sinus variations in this Southern Chinese population. The prevalence of Agger nasi cell and Onodi cell was higher than that of other anatomical variations of the ethmoid sinuses. Anatomical variations of the ethmoid sinuses were not associated with ethmoid or maxillary sinus pathologies in this patient cohort., Competing Interests: Conflicts of Interest: None, (Copyright © 2022 by Korean Academy of Oral and Maxillofacial Radiology.)

There is widespread knowledge that the mental foramen or incisive foramen can be projected onto tooth roots in conventional radiographs, thus simulating apical lesions. In contrast, the anatomical structure of the canalis sinuosus and its branching canals in the anterior maxilla are less known. Sometimes these bone canals mimic a dentino- or osteolysis on conventional radiographs. If these bone canals project onto the roots of the anterior maxillary teeth, there is a risk of misinterpretation as root resorption or apical periodontitis. This case report presents an incidental radiological finding. Due to a radiolucency within the root of tooth 11, root resorption was suspected. Using cone beam-computed tomography, the origin of this radiolucency was clearly identified as an anatomical structure, and the suspected diagnosis was ruled out. This case highlights the importance of the knowledge of anatomical structures to avoid misinterpretations and unnecessary treatments.

Objective: Apical surgery is an intervention to treat teeth with persistent or recurrent endodontic infection. The proximity of the mental foramen and mandibular canal may pose a risk of altered sensation when performing surgical interventions in the posterior mandible. The objective of this study was to determine the rate of neurosensory disturbances after apical surgery of mandibular premolars and molars. The secondary objective was to evaluate whether the occurrence of altered sensation correlated with the distances from the apex or the periapical lesion to the relevant anatomical structures., Methods: The charts of patients treated from September 1999 to December 2015 were retrospectively evaluated if an apical surgery had been performed in mandibular premolars or molars, and a minimum period of 1-year follow-up was documented. Patients with trauma or other surgical interventions in the same hemimandible were excluded. Cases with postsurgical altered sensation were defined as the test group. From the pool of unaffected cases, patients were selected to serve as controls. Two- or three-dimensional radiographs of test and control cases were assessed with regard to the shortest distances from the root apices/lesions to the mental foramen or mandibular canal., Results: The study population included 243 patients with 249 apical surgeries, of which 12.9% led to postoperative neurosensory disturbances. Sensation returned to normal within 22 days on average. The most frequent findings were hyperesthesia or paresthesia. With regard to the treated type of tooth, second premolars resulted more frequently (22.6%) in altered sensation than the other teeth (11.2 to 13.0%; p=0.310). There were no significant differences when comparing test and control cases regarding the measured distances in radiographs from the apex/lesion to the relevant anatomical structures., Conclusion: Altered sensation may typically occur following apical surgery in posterior mandibular teeth. However, in all cases of the present study, skin sensitivity in the lip/chin region returned to normal. The clinician must be particularly careful when performing apical surgery of second premolars due to the proximity of the mental foramen.

Introduction: The objective of this retrospective study was to assess the outcome of periapical surgery in a large number of molars in order to identify possible variables that might affect the outcome., Methods: The healing outcome of patients undergoing periapical surgery of molars from October 1999 to October 2019 was retrospectively evaluated. Outcome was dichotomized into "healed" and "nonhealed" using well-established clinical and radiographic healing criteria. The potential influence of patient-, tooth-, and treatment-related parameters on the healing outcome was analyzed., Results: A total of 424 molars in the same number of patients (45.5% male and 54.5% female) were evaluated. Three hundred seventy-two molars were classified as healed (87.7%). Three significant outcome predictors were identified: 1-year follow-up versus >1-5 years, >5-10 years, and >10 years (95.3% vs 82.2%, 76.3%, and 76.5% healed, respectively; P < .0001); root end filling material with bioceramic root repair material versus mineral trioxide aggregate (96.9% vs. 86.3% healed, respectively; P = .001); and preoperative evaluation based on cone-beam computed tomographic imaging versus 2-dimensional radiography (90.2% vs 81.4% healed, respectively; P = .02). Sex, age, tooth location, type of restoration, attachment level, presence of a post, quality of the root canal filling, technique of root end preparation, administration of antibiotics, and type of surgery had no significant impact on the healing outcome., Conclusions: The healed rate for the concave (Retroplast) and cavity (mineral trioxide aggregate, SuperEBA [Staident International, Staines, UK], and bioceramic root repair material) root end preparation technique over all follow-up periods was 84% and 88.5%, respectively. The follow-up period, root end filling material, and preoperative evaluation based on cone-beam computed tomographic imaging had a significant influence on the healing outcome., (Copyright © 2021 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

The present study aimed to evaluate the morphological characteristics of the sphenoid sinus (SS), and the impact of potential influencing factors on the morphometric features using CBCT imaging. CBCT scans of 148 patients, aged between 15 and 85 (32.88 ± 15.33) years were retrospectively evaluated. DICOM files from the CBCT scans were imported into semi-automatic software and the SS of each patient was assessed for the morphological characteristics including configuration, symmetry, extension, shape, septation, volume, and maximum diameter. Furthermore, potential influencing factors such as age, gender, side, and sinus condition were analysed. A significant association was observed between sinus extension and age. Septation was also found to be significantly associated with age, gender and sinus condition. Besides, sinus volume was significantly associated with gender and sinus condition. No significant influence of shape and side on the morphometric features was noticed. The average volume and diameter of the SS were 6576.92 ± 3748.12 mm 3 and 30.48 ± 9.28 mm, respectively. In conclusion, the present findings indicate that age, gender and sinus condition have a significant impact on the morphometric characteristics of the SS. Mature sinuses exhibit a post-sellar extension pattern until middle age. In addition, males, and sinuses with healthy sinus condition have larger volumes compared to females and pathological sinuses., (© 2021. The Author(s).)

Objectives: To evaluate the long-term effectiveness of 6 mm implants in various indications with a micro-rough surface after 4.6-18.2 years in function and to assess key factors associated with implant survival, success, and biologic/technical complications., Materials and Methods: Fifty-five patients with seventy-four 6 mm implants placed from 2000 to 2013 attended the re-examination assessing well-established clinical and radiographic parameters, biologic and prosthetic complications, and patient-reported outcome measures., Results: Five implants were lost after a mean follow-up period of 9.1 years resulting in a survival rate of 93.2%. All losses occurred in free-end situations in the mandible. Smoking habit significantly reduced implant survival (hazard ratio 36.25). Two implants exhibited a history of peri-implantitis, and one implant showed progressive marginal bone loss (MBL) resulting in a success rate of 89.2%. The mean MBL amounted to 0.029 mm. Increased MBL was found for implants placed in the maxilla (0.057 mm) and for implants with a diameter of 4.1 mm (0.043 mm). Soft tissue thickness (1.39 mm) and width of keratinized mucosa (1.91 mm) had no effect on MBL. Patient-reported outcome measures showed high satisfaction (mean VAS scores 88%) and high quality of life (mean OHIP-G14 score 2.2)., Conclusion: The present study demonstrated survival and success rates of 93.2% and 89.2% for 6 mm implants used in various indications. A factor leading to higher implant failure was smoking, whereas modulating factors increasing annual MBL included implants placed in the maxilla and implants with a diameter of 4.1 mm compared to 4.8 mm., (© 2021 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

The aim of this retrospective study was to assess and illustrate the anatomical variability of the sphenoid sinus (SPS) on cone-beam computed tomography (CBCT) scans. A total of 50 SPS were assessed. CBCT images were oriented in the sagittal plane to evaluate the type of pneumatization (conchal, presellar, sellar and postsellar). Size measurements (width, length and height) of the SPS as well as the septation pattern and the presence or absence of pathologies were examined in all three planes. The postsellar type (28 cases, 56%) was the most common pattern of pneumatization. Conchal, presellar, or sellar pneumatization were significantly less frequent. There was only one case (2%) with a conchal and two cases (4%) with a presellar type. Multiple septa were found in 75% of patients with postsellar pneumatization, but only in 45.5% of patients featuring conchal, presellar or sellar type. In the postsellar category, all measured dimensions were significantly higher compared to the other types of pneumatization. Pathologies in the SPS were found in 7 patients (14%). It was concluded that the anatomical structure of the SPS is highly variable. Knowledge about its radiological appearance in CBCT will help in identification of pathologies and surrounding anatomical structures.

The aim of this study was to evaluate all dento-alveolar injuries occurring within a period of 5 years that were examined at the Department of Oral Surgery and Stomatology at the University of Bern. The case histories of 852 patients (522 males and 330 females) were assessed retrospectively. The mean age was 17 years and 9 months. The youngest patient was 10 months old, the oldest was 91 years old. Most accidents were recorded in the months of March and July. Friday was observed as the weekday when accidents were at their peak. 54% of trauma patients were first examined on the day of the accident. The most frequent causes of accident were falls, cycling or sports accidents. Injury types included concussion (72.4%), subluxation (14%) and luxation (7.7%). Crown fractures without pulp exposure were recorded in 522 teeth (10.7%). Rare types of trauma were crown fractures with pulp exposure (3.7%), and avulsion injuries (3.2%). The most frequently affected teeth were central incisors (40%), followed by lateral incisors (35.6%) and canines (19.5%). 71.5% of the patients with dento-alveolar trauma also had soft-tissue injuries (from abrasions to lacerations), mostly lip (51.6%), gingival (19%), and chin injuries (10.9%). The multivariate analysis showed that age had a significant impact on concussions, subluxations, intrusions, crown fractures, root fractures and non-oral injuries. For concussions and subluxations, the probability of an injury was the highest for the mixed dentition group. For intrusions, the probability of an injury decreased with age, but it was vice versa for crown fractures, root fractures and non-oral injuries. It was found that bicycle injuries had the highest injury probability for avulsions, luxations, subluxations, soft tissue - and non-oral injuries.

Objectives: To assess survival rates and frequency of complications for immature and mature autotransplanted teeth after at least 1 year in function., Materials and Methods: All consecutive patients who had undergone tooth autotransplantation between 2000 and 2018 were invited to a clinical and radiographic follow-up examination. First, survival rates were calculated on the basis of a phone inquiry. A clinical follow-up examination allowed for the calculation of the success rate, i.e., absence of any potentially adverse clinical and radiographic findings of the autotransplanted teeth. Moreover, the effect of demographic, dental, and surgical variables on survival/success was analyzed statistically., Results: Thirty-eight teeth in 35 patients were transplanted during the study period. Three teeth in 3 patients were excluded due to missing records. All other patients were successfully contacted and interviewed by phone. Out of these 35 transplants, 32 were still in function, and 3 had been extracted, yielding a 91.4% survival probability after a median follow-up of 3.4 years. Of the 32 teeth qualifying for the success analysis, 20 (62.5%) showed absence of potentially adverse findings, while 3 (9.4%) required root canal treatment (RCT). Out of the 9 mature, root-end resected transplants, 4 exhibited ongoing pulp canal obliteration, all with a single root canal. Postoperative and potentially adverse findings or failures were found more frequently in the group of mature transplants (55.6%) than immature transplants (30.4%) and for molars (72.7%) than premolars (17.6%) or canines (25%). None of the potential predictors had a statistically significant effect on survival or success., Conclusion: Autotransplanted teeth yielded a satisfying midterm survival rate regardless of their stage of development. An additional, extraoral root-end resection of mature transplants may lead to rates of revascularization and postoperative pulp canal obliteration higher than the data reported on unmodified mature transplants., Clinical Relevance: Extraoral root-end resection of mature teeth shows promising outcomes for transplants especially with a single root canal and uncomplicated root morphology.

N-Heterocyclic carbene (NHC) cyclometalated gold(III) complexes remain very scarce and therefore their photophysical properties remain currently underexplored. Moreover, gold(III) complexes emitting in the blue region of the electromagnetic spectrum are rare. In this work, a series of four phosphorescent gold(III) complexes was investigated bearing four different NHC monocyclometalated (C^C*)-type ligands and a dianionic (N^N)-type ancillary ligand ((N^N)=5,5'-(propane-2,2-diyl)bis(3-(trifluoromethyl)-1 H-pyrazole) (mepzH 2 )). The complexes exhibit strong phosphorescence when doped in poly(methyl methacrylate) (PMMA) at room temperature, which were systematically tuned from sky-blue [λ PL =456 nm, CIE coordinates: (0.20, 034)] to green [λ PL =516 nm, CIE coordinates: (0.31, 0.54)] by varying the monocyclometalated (C^C*) ligand framework. The complexes revealed high quantum efficiencies (ϕ PL ) of up to 43 % and excited-state lifetimes (τ 0 ) between 15-266 μs. The radiative rate constant values found for these complexes (k r =10 3 -10 4  s -1 ) are the highest found in comparison to previously known best-performing monocyclometalated gold(III) complexes. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations of these complexes further lend support to the excited-state nature of these complexes. The calculations showed a significant contribution of the gold(III) metal center in the lowest unoccupied molecular orbitals (LUMOs) of up to 18 %, which was found to be unique for this class of cyclometalated gold(III) complexes. Additionally, organic light-emitting diodes (OLEDs) were fabricated by using a solution process to provide the first insight into the electroluminescent (EL) properties of this new class of gold(III) complexes., (© 2021 Wiley-VCH GmbH.)

Introduction: Vertical root fractures (VRFs) are among the most frequent causes of tooth loss, mainly of endodontically treated teeth. However, very few data is available about the occurrence of VRFs following apical surgery., Methods: Patient charts from 864 patients with 1058 teeth treated with apical surgery (September 1999 to December 2018) were retrospectively evaluated, if a VRF had occurred after surgery. The following, possibly influencing factors were analyzed: sex and age, type of treated tooth, primary versus resurgery, technique of root-end preparation, and timepoint of VRF diagnosis. Endpoints were either tooth extraction or the last follow-up., Results: The study cohort (55% women, 45% men) had a mean age of 52.00 ± 13.97 years (range 9-93 years). The overall rate of VRFs after apical surgery was 4% (42 of 1058 teeth). Among these 42 teeth, 33.3% were mandibular first molars and 26.2% were maxillary second premolars. The most frequently affected root was the mesial root of mandibular first molars (28.6%). With regard to the study parameters, significant differences of VRF rates were observed only for the type of tooth treated., Conclusions: A low VRF rate of 4% was observed in this study. VRFs commonly occurred in maxillary premolars and mandibular molars, with the mesial root of mandibular first molars affected most frequently. This is in line with previous reports about VRFs in endodontically treated teeth without additional apical surgery., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

The mandibular canal is a prominent anatomical structure and it is of great clinical importance since it contains the inferior alveolar nerve. The clinician is advised to proceed cautiously in the vicinity of the mandibular canal to avoid any damage to its neurovascular content. Based on observations in dry mandibles, in panoramic radiographs, and recently in three-dimensional radiography, various anatomical variations of the mandibular canals have been described. One such variant is the so-called bifid mandibular canal (BMC). Embryologically, multiple canals develop and subsequently fuse to form a single mandibular canal; however, occasionally fusion fails or is incomplete resulting in one or multiple BMCs. Clinically relevant issues with regard to the BMCs include hemorrhagic or neurological disorders following damage to these aberrant canals. This literature review presents morphological and quantitative data about BMCs from studies using three-dimensional radiography, i.e. CT and/or CBCT. The reported frequencies of BMCs per patient ranged from 9.8 - 66.5% and per mandibular side from 7.7 - 46.5%. Gender, age or side predilection is currently inconclusive with regard to the occurrence of BMCs. Various types of BMCs have been described in the literature, such as retromolar, dental, forward, or buccolingual canals. BMCs may originate from the mandibular canal along its entire course, but bifurcation appears to be more frequent in the posterior compared to the anterior canal portions. Mean BMC length was reported to range from 10.2 - 16.9 mm, and mean BMC diameter from 0.9 - 2.3 mm. In conclusion, the presence of a BMC must be taken into consideration for treatment planning and anesthetic, endodontic, or surgical interventions in the mandible.