Prevalence and characteristics of and risk factors for impacted teeth with ankylosis and replacement resorption - a retrospective, 3D-radiographic assessment.

Background: Large variation in the prevalence of ankylosis and replacement resorption (ARR) is reported in the literature and most studies have relatively small patient numbers. The present retrospective study aimed to provide an overview on prevalence, location of, and associated risk factors with ARR based on a large sample of computed tomography (CT) / cone beam computed tomography (CBCT) scans of impacted teeth. The results should allow clinicians to better estimate the risk of ARR at impacted teeth.

Clinical and MRI-Based Assessment of Patients with Temporomandibular Disorders Treated by Controlled Mandibular Repositioning.

Background: Occlusal splints and anterior repositioning splints (ARSs) are widely accepted treatments for temporomandibular disorders (TMDs). However, there is uncertainty with regard to the most suitable amount of mandibular repositioning. The aim of this study is to evaluate the clinical and functional effects of the therapeutic position (ThP) established based on the Controlled Mandibular Repositioning (CMR) method.

A novel approach for gingiva thickness measurements around lower anterior teeth by means of dental magnetic resonance imaging.

Objective: This diagnostic accuracy study aims to present the first measurements of gingiva thickness around lower anterior teeth using dental magnetic resonance imaging (MRI) and to compare these measurements with two established methods: (1) gingival phenotype assessment via periodontal probing, and (2) the superimposition of cone-beam computed tomography (CBCT) scans with intraoral scans of teeth and gums.

Materials And Methods: Ten patients with substantial orthodontic treatment need and anterior mandibular crowding were consecutively included in this clinical case series. After periodontal probing, each patient underwent a CBCT scan, an intraoral scan of the mandible, and an MRI investigation using a novel mandibula 15-channel dental coil.

More than urns: A multi-method pipeline for analyzing cremation burials.

Burial rites of archaeological populations are frequently interpreted based on cremated remains of the human body and the urn they were deposited in. In comparison to inhumations, information about the deceased is much more limited and dependent on fragmentation, selection of body regions, taphonomic processes, and excavation techniques. So far, little attention has been paid to the context in which urns are buried.

Static mandibular condyle positions studied by MRI and condylar position indicator.

We compared mandibular condyle positions as determined by magnetic resonance imaging (MRI) and a mechanical device, the condylar position indicator (CPI). Both methods assessed 3 mandibular positions in 10 asymptomatic males and 10 asymptomatic females, aged 23 to 37 years, free from temporomandibular disorders: maximum intercuspation, bimanually manipulated centric relation, and the unguided neuromuscular position. Bite registrations were obtained for bimanual operator guidance and neuromuscular position.

Maxillary lateral incisor agenesis is associated with maxillary form: a geometric morphometric analysis.

Background And Objective: Agenesis of the maxillary lateral incisor occurs in up to 4% of all individuals and requires multidisciplinary treatment. Its developmental origins, however, are not fully understood. Earlier studies documented genetic factors contributing to agenesis but also an association with craniofacial morphology.

Pneumocephalus as result of nonsurgical peri-implantitis treatment with an air-polishing device for submucosal debridement-A case report.

Background: A subcutaneous emphysema is an infrequent but potentially life-threatening complication after dental treatment involving instruments functioning with pressurized air. Emphysemata after the use of high-speed handpieces and air-syringes are well documented, however, more recently several reports on emphysemata produced by air-polishing devices during management of peri-implant biological complications have appeared. To the best of our knowledge, direct development of pneumocephalus after a dental procedure has never been reported before.

Retrospective Evaluation of Implants Placed in Iliac Crest Autografts and Pristine Bone.

Objective: Iliac crest autografts can compensate for severe mandibular atrophy before implant placement. However, the implant success in the augmented bone is not entirely predictable. Here we performed a retrospective cohort study to determine the success and related parameters of implants placed in augmented bone and pristine bone for up to 11 years.

Is MRI a viable alternative to CT/CBCT to identify the course of the inferior alveolar nerve in relation to the roots of the third molars?

Objectives: To assess the reliability of judging the spatial relation between the inferior alveolar nerve (IAN) and mandibular third molar (MTM) based on MRI or CT/CBCT images.

Methods: Altogether, CT/CBCT and MRI images of 87 MTMs were examined twice by 3 examiners with different degrees of experience. The course of the IAN in relation to the MTM, the presence/absence of a direct contact between IAN and MTM, and the presence of accessory IAN were determined.

Angular changes in implants placed in the anterior maxillae of adults: a cephalometric pilot study.

Objectives: Completion of adolescent growth represents the earliest time point for implant placement, yet craniofacial growth persists into adulthood and may affect implant position. We aimed to assess whether implants placed in the anterior maxillae of adults show angular changes over time.

Material And Methods: We conducted a cephalometric pilot study in postpubertal patients with no growth disorders, skeletal malformations, or parafunctions.

Estimated functional space of centric condyle positions in temporomandibular joints of asymptomatic individuals using MRI.

Magnetic resonance imaging (MRI) studies on centric condyle positions lack 3D comparisons of guided and unguided methods, which are used for accomplishing centric relation reference positions. The purpose of this study was to describe the space, in which mandibular condyles are placed in vivo by dental intercuspation, Dawson's bimanual manipulation, and neuromuscular position. Twenty asymptomatic individuals aged 23 to 37 years underwent separate bite registrations using bimanual manipulation and the unguided neuromuscular technique.

Variation in bucco-palatal maxillary sinus width does not permit a meaningful sinus classification.

Objectives: The bucco-palatal sinus width (SW) appears as relevant factor for graft consolidation after maxillary sinus (MS) floor augmentation. The present study aimed to assess (a) SW at different height levels of posterior teeth, (b) possible factors influencing SW, and (c) whether a simple/meaningful sinus classification based on SW is possible.

Methods: The following parameters were recorded on computed tomographies of 76 edentulous and 86 partially edentulous maxillary quadrants displaying 383 tooth sites in total: (a) alveolar ridge height, (b) -area, (c) -width 2 mm apical to the alveolar crest, (d) -width at the sinus floor, and (e) SW and sinus area at a level 2, 4, 6, 8, and 10 mm above the sinus floor.

Association between maxillary lateral incisors' root volume and palatally displaced canines: An instrumental variables approach to the guidance theory.

Objectives:: To evaluate association and causation between maxillary lateral incisors' (MxI2) apical root volume (ARV) and palatally displaced canines (PDC).

Materials And Methods:: In a retrospective cross-sectional study, computed tomography scans of 179 patients with unilateral PDC were analyzed. MxI2 root length and volume on the impaction and eruption side were measured.

Impacted and transmigrated mandibular canines: an analysis of 3D radiographic imaging data.

Objectives: Impacted and transmigrated mandibular canines differ greatly in incidence, etiopathology, associated anomalies, and treatment prospects, when compared to their maxillary counterparts. The aim of this study was to provide a detailed analysis of 3D radiographic imaging data of impacted mandibular canines.

Materials And Methods: In a retrospective cross-sectional study, CT/CBCT data of 88 patients with a total of 94 impacted mandibular canines were analysed.

Timeframe of socket cortication after tooth extraction: A retrospective radiographic study.

Objectives: To assess the timeframe between tooth extraction and radiographically detectable socket cortication in humans.

Methods: Two hundred and fifty patients with a CT scan ≤36 months after tooth extraction were included. First, three orthoradial multiplanar reconstruction slices, representing the major part of the extraction socket, were scored regarding the degree of bone healing as (i) healed, that is, complete/continuous cortication of the socket entrance, or (ii) non-healed.

Alveolar bone resorption after primary tooth loss has a negative impact on straightforward implant installation in patients with agenesis of the lower second premolar.

Objectives: To compare the alveolar bone dimensions in patients with lower second premolar (P2) agenesis prior to and after primary molar loss on CT scans, and assess the possibility for straightforward implant placement.

Methods: Alveolar bone dimensions were evaluated on 150 mandibular CT scans in three groups: (i) agenesis of P2, with the primary tooth in situ, and regularly erupted first premolar (P1) and molar (M1) (AW); (ii) agenesis of P2, without the primary tooth in situ for ≥3 m, but regularly erupted P1 and M1 (AWO); and (iii) P1, P2, and M1 regularly erupted (CTR). The possibility of straightforward placement of an implant 3.

Second premolar agenesis is associated with mandibular form: a geometric morphometric analysis of mandibular cross-sections.

The aim of this study was to compare mandibular form (i.e., size and shape) between patients with agenesis of the lower second premolar (P2) and a control group with no agenesis.

A wide mesio-distal gap in sites of congenitally missing maxillary lateral incisors is related to a thin alveolar ridge.

Objectives: To evaluate (i) a possible correlation between the mesio-distal gap width and the alveolar ridge (AR) dimensions in patients missing the maxillary lateral incisor (I2) either due to agenesis or loss and (ii) the possibility of straightforward implant placement based on simulation.

Methods: The bucco-palatal width, area, and height of the AR at the position of I2, and the mesio-distal gap width between the central incisor and the canine, were assessed in maxillary CT scans of three groups: Patients with (i) agenesis of I2 (T ; n = 40); (ii) I2 regularly erupted but extracted (T ; n = 24); (iii) I2 regularly erupted and in situ (C; n = 40). Further, the possibility of straightforward placement of an implant 3 or 3.

Radiological assessment of the inferior alveolar artery course in human corpse mandibles.

Objectives: CT assessment of the entire course of the inferior alveolar artery (IAA) within the mandibular canal.

Methods: After contrast medium injection (180 or 400 mg/ml iodine concentration) into the external carotid arteries of 15 fresh human cadaver heads, the main IAA's position in the canal (cranial, buccal, lingual or caudal) was assessed in dental CT images of partially edentulous mandibles.

Results: The course of the main IAA could be followed at both iodine concentrations.

Evaluation of three different validation procedures regarding the accuracy of template-guided implant placement: an in vitro study.

Purpose: The study aims to evaluate the accuracy of the NobelGuide™ (Medicim/Nobel Biocare, Göteborg, Sweden) concept maximally reducing the influence of clinical and surgical parameters. Moreover, the study was to compare and validate two validation procedures versus a reference method.

Material And Methods: Overall, 60 implants were placed in 10 artificial edentulous mandibles according to the NobelGuide™ protocol.

Periodontal probing of dental furcations compared with diagnosis by low-dose computed tomography: a case series.

Background: Therapeutic decisions in periodontal surgery are based on the accurate diagnosis of the furcation. Clinical probing is the basic diagnostic tool; however, the accuracy of clinical probing to distinguish Class II and Class III furcation defects is unknown. Therefore, this study compares clinical probing diagnoses to those of computed tomography (CT).

Primary implant stability in the atrophic sinus floor of human cadaver maxillae: impact of residual ridge height, bone density, and implant diameter.

Objectives: Simultaneous implant placement in conjunction with lateral or transcrestal maxillary sinus floor augmentation gives the benefit of reduction in healing times and surgical interventions. Primary implant stability, however, may be significantly reduced in resorbed residual ridges. Aim of the present study was to investigate the impact of residual bone height, bone density, and implant diameter on primary stability of implants in the atrophic sinus floor.

A retrospective study on the influence of maxillary canine impaction on premolar root morphology.

Objectives: The root morphology of the maxillary first premolar differs from the other premolars by presenting a high incidence of separated roots. This study addressed the spatial conditions during root development as a possible influencing factor. Therefore, maxillary computed tomographic (CT) scans of patients with regularly erupted or impacted permanent canines were evaluated on the root morphology of the premolars.

The prevalence of root resorption of maxillary incisors caused by impacted maxillary canines.

Objectives: The aim of this study was to evaluate the prevalence of root resorption of maxillary incisors caused by impacted maxillary canines using low-dose dental computed tomography and to gain additional knowledge of the underlying aetiology and the progression of root resorption.

Materials And Methods: A total of 440 patients (mean age, 24.7 years) with 557 impacted maxillary canines were examined regarding their location and the occurrence of root resorption of maxillary incisors.

Effect of maxillary sinus floor augmentation on sinus membrane thickness in computed tomography.

Background: Little is known about maxillary sinus compliance, i.e., the intrinsic potential of the sinus membrane to resume its homeostatic status after the surgical trauma caused by sinus floor elevation.