Search

Background: Tooth-supported surgical guides have demonstrated superior accuracy compared with bone-supported guides. This study aimed to modify the fabrication of tooth-supported guides for compatibility with tumor resection procedures and investigate their accuracy., Methods: Patients with tumors who underwent osteotomy with the assistance of modified tooth- or bone-supported surgical guides were included. Virtual surgical planning (VSP) was employed to align three dimensional (3D) models extracted from intraoperative computed tomography (CT) images. The distances and angular deviations between the actual osteotomy plane and preoperative plane were recorded. A comparative analysis of osteotomy discrepancies between tooth-supported and bone-supported guides, as well as among tooth-supported guides based on CT, cone-beam CT (CBCT), or intraoral scanner (IOS) was conducted. The factors influencing the precision of the guides were analyzed., Results: Sixty patients with 81 resection planes were included in this study. In the tooth-supported group, the mean deviations in the osteotomy plane and angle were 1.39 mm and 4.30°, respectively, whereas those of the bone-supported group were 2.16 mm and 4.95°. In the tooth-supported isotype guide groups, the mean deviations of the osteotomy plane were 1.39 mm, 1.47 mm, 1.23 mm across CT, CBCT, and IOS, respectively. The accuracy of the modified tooth-supported guides remained consistent regardless of number and position of the teeth supporting the guide and location of the osteotomy lines., Conclusions: The findings indicate that the modified tooth-supported surgical guides demonstrated high accuracy in the maxillofacial region, contributing to a reduction in the amount of surgically detached soft tissue., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Background: Tooth replacement patterns of early-diverging ornithischians, which are important for understanding the evolution of the highly specialized dental systems in hadrosaurid and ceratopsid dinosaurs, are poorly known. The early-diverging neornithischian Jeholosaurus, a small, bipedal herbivorous dinosaur from the Early Cretaceous Jehol Biota, is an important taxon for understanding ornithischian dental evolution, but its dental morphology was only briefly described previously and its tooth replacement is poorly known., Results: CT scanning of six specimens representing different ontogenetic stages of Jeholosaurus reveals significant new information regarding the dental system of Jeholosaurus, including one or two replacement teeth in nearly all alveoli, relatively complete tooth resorption, and an increase in the numbers of alveoli and replacement teeth during ontogeny. Reconstructions of Zahnreihen indicate that the replacement pattern of the maxillary dentition is similar to that of the dentary dentition but with a cyclical difference. The maxillary tooth replacement rate in Jeholosaurus is probably 46 days, which is faster than that of most other early-diverging ornithischians. During the ontogeny of Jeholosaurus, the premaxillary tooth replacement rate slows from 25 days to 33 days with similar daily dentine formation., Conclusions: The tooth replacement rate exhibits a decreasing trend with ontogeny, as in Alligator. In a phylogenetic context, fast tooth replacement and multi-generation replacement teeth have evolved at least twice independently in Ornithopoda, and our analyses suggest that the early-diverging members of the major ornithischian clades exhibit different tooth replacement patterns as an adaption to herbivory., (© 2024. The Author(s).)

Subcapsular transplantation of developing tissues and organs into the richly vascularized murine kidney provides the necessary trophic support, thus ensuring proper completion of their growth. 1 , 2 , 3 Here, we provide a protocol for kidney capsule transplantation that allows the full differentiation of embryonic teeth previously exposed to chemicals. We describe steps for dissection and in vitro culture of embryonic teeth, followed by transplantation of tooth germs. We then detail harvesting of kidneys for further analysis. For complete details on the use and execution of this protocol, please refer to Mitsiadis et al. 4 ., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Acellular dermal matrix (ADM) is commonly used for soft tissue augmentation in root coverage, increasing the width of keratinized gingiva or vestibular depth, or filling the localized alveolar bone defects. This parallel-design randomized controlled clinical trial assessed the effect of ADM membrane placement simultaneous with implant placement on vertical soft tissue thickness. A total of 25 submerged implants were placed in 25 patients (8 men, 17 women) with vertical soft tissue thickness < 3 mm at the surgical site. Patients were randomized into two groups: The intervention group (n = 13) received ADM over the implant for soft tissue augmentation, while no augmentation was performed for the control group (n = 12). After 3 months, healing abutments were placed, and the soft tissue thickness at the surgical site was measured again with a periodontal probe in both groups. Data were analyzed using Mann-Whitney and Wilcoxon tests. All 25 patients were successfully treated. The presurgical vertical soft tissue thickness was 2 mm and 1.92 mm in the control and test groups, respectively ( P > .05). These values changed to 1.83 mm and 2.69 mm, respectively, after the intervention. The mean gain in soft tissue thickness was 0.76 mm in the test group, and the difference between groups was statistically significant ( P < .05). ADM membrane can be successfully used to augment vertical soft tissue thickness simultaneous with implant placement.

The importance of a judicious and unerring abutment tooth preparation in the field of prosthodontics has always been paramount. It is not uncommon for many clinicians to face challenges during laboratory fabrication of fixed prostheses, caused due to inappropriate occlusal clearance and over axial wall taper of the abutment tooth. With evolving technologies and methods, the modus operandi for attaining such tooth preparation is varying; however, every technique has its own shortcomings. The technique mentioned in the article is cost-effective as it uses modified Heister mouth gag forceps to achieve the desired objective of evaluating the prepared abutment morphology three-dimensionally with minimum chairside time., Competing Interests: None

Introduction: Pain and complications are common after surgical removal of impacted third molars. The present study was undertaken to evaluate the effect of an oleous suspension of calcium hydroxide (OSTEORA) on pain severity and complications after surgical removal of impacted third molars. Materials and methods: This clinical trial evaluated 30 patients with an age range of 17‒40, referring to a maxillofacial surgery department and two private clinics in Tehran in 2011‒2012 for surgical removal of bilaterally impacted third molars with the same difficulty index. OSTEORA was used on one side and no material was used on the contralateral side as the control. The effect of OSTEORA was evaluated on pain, healing, hemorrhage, dry socket and infection at different postoperative intervals in a double-blind manner. Data were analyzed with chi-squared and MannWhitney U tests (α=0.05). Results: Of 60 samples, 28 were from the maxilla and 32 were from the mandible. Intensity of pain in the study groups at baseline and at follow-up intervals was the same (p value = 0.4). The incidence of hemorrhage at follow-ups was the same in both groups (p value < 0.5). Maxillary healing rates on the 3rd postoperative day in the control and test groups were 3.21±2.39 and 2.42±2.17, respectively (p value < 0.03) and on the 7th postoperative day they were 2.9±2.58 and 2.14±2.28, respectively (p value < 0.03). Healing in mandible in both groups was the same at follow-ups (p value < 0.2). No dry sockets and infection were observed in any subject. Conclusions: Under the limitations of the present study, use of an oleous suspension of calcium hydroxide had no effect on the incidence of hemorrhage and pain after surgical removal of impacted third molars. However, it affected healing of the surgical site, especially in the maxilla. [ABSTRACT FROM AUTHOR]

Medical records from 4 private practice veterinary dentistry specialty clinics were reviewed for a 5-year period (2013-2018) to identify dogs that had a fractured canine tooth treated by root canal therapy and returned for subsequent follow-up evaluation. Evaluation criteria included the presence of complete medical records with diagnostic quality intraoral radiographs for each procedure visit with a minimum of 6 months between visits. Forty-three dogs with a total of 55 endodontically treated canine teeth were identified and evaluated. Root canal treatment outcome was defined as successful, no evidence of failure (NEF), or failure based on radiographic findings. Patient age, time from initial treatment to follow-up, obturation material used, radiographic quality of obturation (including voids, overfill, and retention of fractured endodontic files), radiographic evidence of periapical disease and/or presence of external inflammatory root resorption (EIRR), and the presence or absence of a full coverage metal crown were evaluated. Treatment was classified as successful in 51 (92.73%) teeth, NEF in 3 (5.45%) teeth, and failure in 1 (1.82%) tooth. The results suggest that endodontic treatment of fractured canine teeth in dogs is a successful treatment option that allows for retention of this functionally important tooth.

Objectives: Intraoral photographs might be considered the machine-readable equivalent of a clinical-based visual examination and can potentially be used to detect and categorize dental restorations. The first objective of this study was to develop a deep learning-based convolutional neural network (CNN) for automated detection and categorization of posterior composite, cement, amalgam, gold and ceramic restorations on clinical photographs. Second, this study aimed to determine the diagnostic accuracy for the developed CNN (test method) compared to that of an expert evaluation (reference standard)., Methods: The whole image set of 1761 images (483 of unrestored teeth, 570 of composite restorations, 213 of cements, 278 of amalgam restorations, 125 of gold restorations and 92 of ceramic restorations) was divided into a training set (N = 1407, 401, 447, 66, 231, 93, and 169, respectively) and a test set (N = 354, 82, 123, 26, 47, 32, and 44). The expert diagnoses served as a reference standard for cyclic training and repeated evaluation of the CNN (ResNeXt-101-32 × 8d), which was trained by using image augmentation and transfer learning. Statistical analysis included the calculation of contingency tables, areas under the receiver operating characteristic curve and saliency maps., Results: After training was complete, the CNN was able to categorize restorations correctly with the following diagnostic accuracy values: 94.9% for unrestored teeth, 92.9% for composites, 98.3% for cements, 99.2% for amalgam restorations, 99.4% for gold restorations and 97.8% for ceramic restorations., Conclusions: It was possible to categorize different types of posterior restorations on intraoral photographs automatically with a good diagnostic accuracy., Clinical Significance: Dental diagnostics might be supported by artificial intelligence-based algorithms in the future. However, further improvements are needed to increase accuracy and practicability., (Copyright © 2022. Published by Elsevier Ltd.)

Inadvertent Er:YAG laser irradiation occurs in dentistry and may harm restorative materials in teeth. The aim of this in vitro study was to quantify Er:YAG laser-induced damage to a nanohybrid composite in simulated clinical scenarios for inadvertent direct and indirect (reflection) laser irradiation. The simulation was performed by varying the output energy (OE;direct˃indirect) reaching the specimen and the operating distance (OD;direct˂indirect). Composite specimens were irradiated by an Er:YAG laser. The ablation threshold was determined and clinically relevant parameters were applied (n = 6 for each OE/OD combination) for direct (OE: 570 mJ/OD: 10 mm, OE: 190 mJ/OD: 10 mm) and indirect irradiation (OE: 466 mJ/OD: 15 mm, OE: 57 mJ/OD: 15 mm, OE: 155 mJ/OD: 15 mm, OE: 19 mJ/OD: 15 mm). The extent of damage in the form of craters was evaluated using a laser scanning microscope (LSM) and a conventional light microscope (LM). The ablation threshold was determined to be 2.6 J/cm 2 . The crater diameter showed the highest value (LM: 1075 ± 18 µm/LSM: 1082 ± 17 µm) for indirect irradiation (reflectant:dental mirror) (OE: 466 mJ/OD: 15 mm). The crater depth showed the highest and comparable value for direct (OE: 570 mJ/OD: 10 mm; LSM: 89 ± 2 µm) and indirect irradiation (OE: 466 mJ/OD: 15 mm; LSM: 90 ± 4 µm). For each OD, the crater diameter, depth, and volume increased with higher laser fluence. However, the OD-and thus the laser spot diameter-also had an enlarging effect. Thus, indirect irradiation (reflectant:dental mirror) with only 47% of the laser fluence of direct irradiation led to a larger diameter and a comparable depth. The three-dimensional extent of the crater was large enough to cause roughening, which may lead to plaque accumulation and encourage caries, gingivitis, and periodontitis under clinical conditions. Clinicians should be aware that reflected irradiation can still create such craters., (© 2021. The Author(s).)

Bacteremia resulting from dental surgery is increasingly recognized as a health risk, especially in older and immunocompromised patients. Dentistry-associated bacteremia can lead to remote infections, as exemplified by valvular endocarditis. Emerging evidence points to a novel role played by oral cavity commensals in the pathogenesis of diabetes, respiratory disease, cardiovascular disease, and adverse pregnancy outcomes. Whether dental extraction, a commonly undertaken procedure in old horses, causes bacteremia has not been reported extensively. In a prospective clinical study using next generation sequencing (based on bacterial 16S rRNA), the circulating blood microbiome was characterized before and at 1 h following extraction of incisor, canine or cheek teeth from 29 adult horses with dental disease. 16S rRNA gene sequencing results from the blood microbiome were compared with those from gingival swab samples obtained prior to extraction at the location of the diseased tooth. Bacteremia associated with translocated gingival commensals was demonstrated in horses undergoing exodontia and was, in some cases, still evident one hour post-operatively.

A hopeless tooth from a periodontal point of view, with severe bone resorption, mobility and abnormal tooth migration, is often extracted. In advanced cases, function and esthetics are impaired, and an interdisciplinary treatment is requested. Retaining or not these teeth is based on clinician judgment. A growing body of evidence claims that prognosis has great potential to be improved in a motivated patient with good oral hygiene and regular maintenance. This case report aims to present a periodontal regenerative technique combining enamel matrix protein derivatives and a particulated xenograft to treat intraosseous defects caused by periodontitis. The patient healed uneventfully, and no complications were recorded after the surgical procedure. To correct abnormal tooth migration and improve function and esthetics, orthodontic treatment was instituted. Tooth prognosis improved from hopeless to questionable. This approach extended the life span of a compromised tooth, improving periodontal support and decreasing tooth mobility. This could be an alternative to extraction and implant., (©2021 JOURNAL of MEDICINE and LIFE.)

Objective: Autogenous tooth bone grafts (ATGM) are materials prepared from extracted teeth and have been used for bone augmentation. These graft materials are known to have similar structures and components to bone grafts. In this sense, this study aimed to evaluate all the tooth layers mixed with simvastatin without any demineralization process effect on bone formation., Methods: In 60 Wistar albino rats, a standardized 6.0 m-diameter critical size bone defect was created in their calvarium. The study consists of 1 control and 4 experimental groups. In the control group (12 rats), the defects were left empty. The defects were grafted only with ATGM in Group 1, with ATGM mixed with simvastatin in Group 2, autogenous bone graft mixed with simvastatin in Group 3, and with xenogenic bone graft mixed with simvastatin in Group 4. The animals were sacrificed at the 7th and 28th days after operation., Results: PCR, micro CT and histological results show that bone formation was enhanced in the experimental groups in comparison to the control group. Group 1 and Group 2 had similar bone formation rate when compared to Group 3 and Group 4 at the 28th day after operation., Conclusion: This study concludes that mineralized teeth may be used for defect reconstruction without any demineralization process. Autogenous mineralized tooth bone graft should be mixed with simvastatin for bone regeneration like other grafts.

This case report describes the diagnosis, multidisciplinary treatment, and long-term follow-up of a severely compromised tooth in a patient who was referred for assessing a gingival recession. Clinical evaluation of the left maxillary canine showed 12 mm of mid-buccal gingival recession, probing depth of 14 mm on the mesial-buccal aspect, and grade III mobility. A periapical radiograph revealed extensive periapical and lateral radiolucency. The first step of the treatment was to carry out oral hygiene instructions and full-mouth debridement. After that, endodontic treatment was performed immediately. Periodontal reevaluation four months after endodontic therapy revealed that probing depths of all sites were within 3 mm and periapical radiograph showed a slight decrease in periapical and lateral radiolucency. It was subsequently decided to perform root coverage with a laterally positioned flap and subepithelial connective tissue graft. Six months after surgery, the root surface showed 1 mm recession, representing root coverage of 91.7% and a gain of attachment of 13 mm. The patient was enrolled in a 6-month supportive periodontal therapy. Treatment outcomes were evaluated over 18 years, with successful radiographic and clinical results throughout the follow-up period. The successful management of endo-periodontal lesions requires an accurate diagnosis, which is imperative to provide proper therapy in the correct treatment sequence., (©Carol Davila University Press.)

Introduction: Laser doppler flowmetry is a non-invasive method of measuring microcirculatory blood flow in tissue. Using laser doppler flowmetry Moor VMS-LDF1-HP and CP1T-HP probe combined with Moor VMS-PC software to evaluate the state of the periapical lesion (cyst) before nonsurgical endodontic treatment with bioceramics (Well Root SP™) and compare it to a healthy vital tooth of the same type with no periapical lesions. Later the bony crypt of the cyst was evaluated with Moor VMSLDF1-HP and VP7BS-HP probe during periapical surgery after the cyst was ablated with Er: YAG laser Lite Touch™ (Sineron, Israel) and retrogradely obturated with TheraCal LC®. Then the cyst received a bioceramic bone graft. To our knowledge, this is the first time laser doppler has been used during periapical surgery to evaluate tissue perfusion. Lesion type was confirmed with a histological examination after surgery., Aim: Evaluate tissue perfusion of a periapical lesion before nonsurgical treatment and during surgical endodontic treatment with Er:YAG laser with the help of laser doppler flowmeter., Results: Laser doppler flowmetry shows that the cystic tooth has a decreased blood flow, decreased concentration, direct current, speed, and lower temperature compared to a healthy tooth of the same type. During periapical surgery, the direct laser blood flow evaluation of the surgical crypt shows different values of the flux, speed, direct current, concentration, and temperature, which could be attributed to the mechanical trauma, adrenaline in the local anaesthetic or laser irradiation of tissues., Conclusions: Laser doppler flowmetry is a valuable method to perform tissue evaluation before, during and after treatment. It allows us to follow up the healing and pathological dynamics of microcirculatory tissue changes as well as evaluate and compare different methods and materials for treatment of apical periodontitis., (This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Periodontally affected teeth with periapical lesion indicated for periapical surgery have a poor prognosis. Using Er:YAG lasers to perform simultaneous surgery on both defects may increase their survival rate. Preparing a retrograde cavity on affected teeth and obturating it is still a matter of debate among clinicians. The purpose of this case report was to describe the simultaneous use of Erbium-doped Yttrium Aluminium Garnet Er:YAG (2,940 nm) laser in the treatment of periapical granuloma and infraossal defect and the achieved results. The Er:YAG laser was used to perform flap dissection, granulation tissue removal, osteotomy and root-end resection except for initial flap incision and reflection. The cystic cavity was filled with Bio-Oss Collagen® xenograft. Results were followed up for 18 months with the help of radiographic orthopantomographic images. The outcome of this clinical case indicates that the use of Er:YAG laser could be considered a suitable method to perform simultaneous periodontal and endodontic surgery., (This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Reptiles with continuous tooth replacement, or polyphyodonty, replace their teeth in predictable, well-timed waves in alternating tooth positions around the mouth. This process is thought to occur irrespective of tooth wear or breakage. In this study, we aimed to determine if damage to teeth and premature tooth extraction affects tooth replacement timing long-term in juvenile green iguanas (Iguana iguana). First, we examined normal tooth development histologically using a BrdU pulse-chase analysis to detect label-retaining cells in replacement teeth and dental tissues. Next, we performed tooth extraction experiments for characterization of dental tissues after functional tooth (FT) extraction, including proliferation and β-Catenin expression, for up to 12 weeks. We then compared these results to a newly analyzed historical dataset of X-rays collected up to 7 months after FT damage and extraction in the green iguana. Results show that proliferation in the dental and successional lamina (SL) does not change after extraction of the FT, and proliferation occurs in the SL only when a tooth differentiates. Damage to an FT crown does not affect the timing of the tooth replacement cycle, however, complete extraction shifts the replacement cycle ahead by 4 weeks by removing the need for resorption of the FT. These results suggest that traumatic FT loss affects the timing of the replacement cycle at that one position, which may have implications for tooth replacement patterning around the entire mouth., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.)

The objective of this study was to assess the biomechanical effects of different corticotomy designs used for orthodontic anterior retraction through finite element analysis., Materials and Methods: A basic finite element model simulating retraction of anterior teeth was built reversely from CBCT films of an adult patient with protruded maxillary anterior teeth. Another thirteen FE models were created according to different corticotomy designs varied with site width and the extent of incision. The initial displacement, Von Mises stress and pressure stress of dento-alveolar structures was computerized and analyzed., Results: Corticotomy can increase the initial displacement of anterior segment including teeth and surrounding alveolar bone, change the distribution of Von Mises stress in cancellous bone and the pressure stress in periodontal ligament of anterior teeth. When the incision was near the periphery of apical, the anterior segment showed the greatest displacement, the cancellous bone at either sockets or incision region showed the maximum stress. Bilateral incision combined with palatal incision showed approximate initial displacement and stress distribution with circumscribing incision. While the incision width increased, the biomechanical effects of corticotomy amplified., Conclusions: Varied corticotomy designs can change the biomechanical effects on dento-alveolar structures. The incision near the periphery of apical and bilateral incision combined with palatal incision may be the optimized design used for retraction of anterior teeth.

Background: The purpose of this study was to assess the quantity of the chelated calcium ions and the smear layer removal efficiency after root canal final irrigation with three different solutions., Materials and Methods: Forty-five teeth were instrumented with rotary-files, then randomly divided into 3 equal groups (n = 15) depending on the final irrigation solution; group I: 17% ethylenediaminetetraacetic acid (EDTA), group II: 0.2% chitosan, and group III: 10% trisodium citrate. According to the time of application, every group was divided into 3 subgroups (1 min, 5 min, and 24 h). The quantification analysis of chelated calcium ions was performed by flame atomic absorption spectrometry (FAAS). Then, the presence of smear layer was examined by splitting the samples longitudinally and using scanning electron microscopy (SEM) to examine coronal, middle, and apical root canal levels. One-way analysis of variance (ANOVA) test was used for the evaluation of treatment effect. Kruskal-Wallis test was executed to detect a significant difference between groups, while Mann-Whitney U test has determined the difference between each two groups for smear layer., Results: Both 17% EDTA and 0.2% chitosan had not been statistically significant difference for smear layer removal efficiency and observed calcium ion concentrations. Although, they were more efficient of 10% trisodium citrate with a significant difference (P < 0.05)., Conclusion: The application time of the chelators' solutions must not exceed 5 min to completely remove smear layer, and 0.2% chitosan is a natural substitute for 17% EDTA with a safety application for 24 h., Competing Interests: None

Amelogenesis imperfecta (AI) is an enamel defect and is often associated with the anterior open bite (AOB) and transverse maxillary deficiency. It is known that in such cases when AI and AOB appeared together, posterior maxillary impaction with or without bilateral mandibular ramus osteotomies is a frequently preferred treatment option. Virtual planning is more reliable rather than the conventional model surgery planning, especially for complicated cases. Usage area of virtual 3D anatomical models reconstructed from Cone Beam Computed Tomography (CBCT) data is expanding day by day for both diagnosis and surgical planning. The aim of this study is to present a patient with AI and AOB and transverse maxillary deficiency and management of this case with virtually planned two-segment Le fort I and sagittal split ramus osteotomies followed by prosthetic rehabilitation., Competing Interests: None

This trial assessed post-operative pain and healing of apical periodontitis following endodontic therapy with a reciprocating system compared to a crown-down technique with hand files and lateral compaction filling. One-hundred and twenty nonvital anterior teeth with apical periodontitis were randomly treated using either a reciprocating single file followed by matching-taper single-cone filling or a hand file and lateral compaction filling. Postoperative pain was assessed during the 7 days after the treatment, using a visual analogue scale and a verbal rating scale. Apical healing was assessed using the periapical index score after a 12-month follow-up. The hypothesis tested was that both protocols were equivalent and present similar effectiveness in healing periapical lesions. Data were analyzed through two one-sided tests, t-tests, as well as Mann-Whitney and Chi-squared tests (α = 0.05). Logistic regression was used to investigate the association of clinical and demographic factors with the success of treatment. Regardless of the assessment time, no difference in incidence (38%-43% at first 24h), intensity of postoperative pain, and incidence of flare-up (≈ 3%) was observed between the two endodontic protocols. Both protocols resulted in a similar healing rate of apical periodontitis. After 12 months, the success rate ranged from 73% to 78% and the difference between the treatments fell within the pre-established equivalence margin (-0.1; -0.41 to 0.2). Endodontic treatment combining a reciprocating single file with matching-taper single cone showed similar clinical effectiveness to the treatment using hand-file instrumentation and the lateral compaction filling., Competing Interests: The authors have declared that no competing interests exist

Maxillary constriction is a common skeletal craniofacial abnormality, and transverse maxillary deficiency affects 30% of patients receiving orthodontic and surgical treatment. The aim of the study was to analyse craniofacial skeletal changes in adults with maxillary constriction after transpalatal distraction. The study group consisted of 36 patients (16 women) aged 17 to 42 years ( M  = 27.1; SD = 7.8) with a known complete skeletal crossbite and who underwent transpalatal distraction procedure. The measurements were obtained on diagnostic models, and cephalometric PA radiograms were obtained at time points, i.e., before treatment (T1) and after the completion of active distraction (T2). The analysis of diagnostic models involving the arch width measurement at different levels demonstrated a significant increase in L1, L2, L3, L4, L5, and L6 dimensions after transpalatal distraction. The largest width increase (9.5 mm) was observed for the L3 dimension (the intercanine distance). The analysis of frontal cephalograms displayed a significant increase in W1, W2, and W3 dimensions after transpalatal distraction. The largest width increase (4.9 mm) was observed for the W1 dimension at the level of the alveolar process of the maxilla. Transpalatal distraction is an effective treatment for transverse maxillary deficiency after the end of bone growth. The expansion observed on diagnostic models is close to a parallel segment shift mechanism, with a mild tendency towards a larger opening anteriorly. The maxillary segment rotation pattern analysed based on the frontal cephalograms is close to a hand fan unfolding with the rotation point at the frontonasal suture., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this paper., (Copyright © 2020 Ewa Zawiślak et al.)

Objective: To evaluate skeletal and dental changes in patients with skeletal Class III malocclusion and facial asymmetry after surgical-orthodontic treatment using cone-beam computerized tomography (CBCT)., Methods: This study included forty adult patients diagnosed with skeletal Class III malocclusion and asymmetry who underwent either isolated mandibular surgery or bimaxillary surgery. CBCT scans were taken before treatment (T0), at the completion of presurgical orthodontic treatment (T1) and after treatment (T2). Mimics 17.0 and 3-Matics 7.0 were used to measure skeletal and dental parameters. Skeletal and dental changes within each group from pretreatment to posttreatment were assessed, and Pearson correlation analysis was used to analyze the correlations among skeletal changes., Results: The three-dimensional changes in condylar position were insignificant after surgical-orthodontic treatment in either group (P > 0.05). However, in the one-jaw surgery group, there were significant backward rotations of the condyle and ramus on the nondeviated side (P < 0.05), and the condyle on the deviated side rotated inward and forward significantly in the two-jaw surgery group (P < 0.05) at T2. There were no significant differences in the changes in the total alveolar bone thickness of bilateral first molars during dental decompensation (P > 0.05). The ratio between the buccal and the total bone thickness around the maxillary first molar on the deviated side decreased significantly at T1, as did those around the mandibular first molar on the nondeviated side (P < 0.05)., Conclusions: Condylar angulations were less stable after treatment (7 to 9 months after surgery) in both the one-jaw and the two-jaw surgery groups, while condylar displacements were insignificant. In addition, orthodontists should keep a watchful eye to the relative position of the root in the alveolar bone during tooth decompensation.

In this report, we describe an innovative bolstering technique that resulted in successful skin graft take to the floor of the mouth when the teeth and alveolus were unavailable for anchorage.

Objective: The aim of this study was to evaluate the efficacy of different irrigation protocols in removing two tricalcium silicate-based sealers from simulated root canal irregularities and root canal walls., Material and Methods: Root canals of 140 single-rooted teeth were instrumented. In one-half of each root, an apical groove was created. The samples were divided into two main groups (n = 70) based on the sealer used. In group 1, the grooves were filled with MTA Fillapex; in group 2, BioRoot RCS. The reassembled root halves were divided into six experimental and one control groups: 2.5% NaOCl-17% EDTA (Passive ultrasonic irrigation [PUI]), 5% NaOCl/9% DualRinse HEDP (PUI), 2.5% NaOCl-7% Maleic acid (PUI), 2.5% NaOCl-17% EDTA (Er:YAG laser activated irrigation [LAI]), 2.5% NaOCl/9% DualRinse HEDP (LAI), 2.5% NaOCl-7% Maleic acid (LAI), Distilled water (Control). Specimens were scored using SEM. The data were analysed using Kruskal-Wallis and Mann Whitney U tests., Results: Maleic acid and DualRinse HEDP removed higher amounts of MTA Fillapex from the grooves compared to EDTA, when used with both activation methods (p < .001)., Conclusions: Ultrasonically activated maleic acid or DualRinse HEDP can be an effective irrigation regimen in removing tricalcium silicate-based sealers., (© 2019 Wiley Periodicals, Inc.)

Background: Cone-beam computed tomography (CBCT) presurgical assessment on the maxillary sinus can reduce the possibility of Schneiderian membrane perforation. This study examined Schneiderian membrane thickness (SMT) and its relationship with neighboring hard tissues for patients with and without membrane thickening. For patients with sinus infections, we evaluated dimensional changes of the SMT post-extraction relative to pre-extraction SMT and residual bone height (RBH)., Methods: CBCT images from 93 patients needing single-tooth implant reconstruction without (n = 83) and with (n = 14) odontogenic infected maxillary sinuses were assessed. SMT, RBH, and lateral wall thickness (LWT) were measured. Causes of extraction, RBH in the infection site, and retrospective post-extraction record of SMT were recorded for the thickened SMT group., Results: Mean SMT for normal SMT group was 1.13 ± 0.43 mm, RBH was 6.26 ± 2.38 mm; upper and lower LWT was 1.85 ± 0.95 mm, and 3.07 ± 2.26 mm, respectively. RBH and LWT had no significant relationships with SMT. For thickened SMT group, mean values for SMT and RBH prior to extraction were 4.53 ± 2.46 mm and 1.97 ± 1.43 mm, respectively. Pre-extraction SMT had a moderately negative correlation with pre-extraction RBH. SMT resolution in thickened SMT group was observed by 2.80 ± 1.37 months post-extraction; post-extraction SMT was not significantly different from normal SMT group (p = .187)., Conclusions: Within the limitation of the sample size, thickened SMT induced by odontogenic infection subsides about 3 months following tooth extraction, and further sinus lifting implant surgery may be considered., (Copyright © 2019 Chang Gung University. Published by Elsevier B.V. All rights reserved.)

Dental replicas are frequently utilized in paleoanthropological studies of perikymata and enamel hypoplasia. However, fossil teeth are often fragile and worn, causing two problems: (1) the risk of damage by removing enamel fragments when impression-making material is separated from the fossil tooth surface, and (2) the need to reconstruct worn portions of the crown to assess perikymata number, distribution, and hypoplasia timing. This study presents the advantages of μCT data of canines and lateral incisors for (1) detecting cracks along the enamel-dentine junction (EDJ) which could cause damage when casting, and (2) reliably and non-destructively reconstructing worn or broken cusps. Fragile teeth of Homo naledi, Miocene, and Pleistocene specimens were μCT-scanned: 2D virtual sections and 3D models allowed for inspecting crack pattern beyond the external surface and 2D virtual sections were used to digitally reconstruct cusp tips (only Homo naledi). Micro-CT scans allowed cracks running along the EDJ and communicating with radial cracks in the enamel to be identified prior to casting. Cusp reconstructions using μCT data were conducted as precisely as when using thin-sections or photographs, and with high intra- and inter-observer agreement, while preserving the original specimen and affording numerous planes of virtual section. When available, μCT data should be inspected prior to tooth casting to exclude teeth that show a pattern of cracks that could lead to damage. Virtual sections allow for accessible, reliable, and non-destructive cusp reconstructions that may be used for developmental (e.g., perikymata and enamel hypoplasia) or enamel thickness studies. Anat Rec, 302:1516-1535, 2019. © 2018 American Association for Anatomy., (© 2018 American Association for Anatomy.)

To evaluate effects of tail docking and/or teeth clipping on sows and their piglets, a total of 24 sows and their 302 piglets at 3 days of age were randomly allocated to one of four treatments: teeth clipping and tail docking (TCTD), teeth clipping (TC), tail docking (TD), or intact teeth and tail (Intact). Behavior of piglets and sows, lesions on the body and tail of piglets and sows' teats were inspected. Heart rates of processed piglets were increased (p < .01) during the procedures. Teeth clipping decreased body surface temperature (p < .01) of piglets during and after the procedures but tail docking did not (p > .01). Processed piglets spent more (p < .05) time lying alone and playing/fighting than sham-processed piglets. Tail docked piglets spent less (p < .01) time standing than tail sham-docked piglets. Intact teeth increased (p < .05) the avoidance behaviors of sows. Teeth clipping decreased (p < .05) the lesion scores on the anterior, middle, and posterior teats. Taken together, piglet teeth clipping had more impact on sows and their piglets than tail docking did in the lactation period based on our findings., (© 2019 Japanese Society of Animal Science.)

Painful processing procedures in piglets such as tail docking, castration, and teeth clipping are an emerging animal welfare concern. We hypothesized that transmammary delivery of a nonsteroidal anti-inflammatory drug, firocoxib, would reduce pain associated with processing in piglets. This study compared the pharmacokinetics, efficacy, safety, and tissue residue concentrations of 4 doses of firocoxib (0.5, 1.0, 1.5, or 2.0 mg/kg) administered to sows and delivered to nursing piglets prior to processing. Sixteen sows, 5 ± 2 d postpartum, were randomly assigned to 1 of 4 treatment groups. On day 0, sows received a single intramuscular dose of firocoxib at 7 ± 1 h before piglet surgical castration, tail docking, and teeth clipping (males) or sham handling (females). Firocoxib and cortisol concentrations were determined from selected samples collected from sows and 3 piglets per litter (2 barrows and 1 gilt) at 0, 2, 4, 6, 8, 12, 24, 48, 72, 96, and 120 h after drug administration. On day 21, piglets were weighed and all animals were euthanized and necropsied. Tissues were collected from 3 piglets per litter for histological examination and drug residue analysis. Mean (±SEM) peak plasma firocoxib concentrations (Cmax) were 107.90 ± 15.18, 157.50 ± 24.91, 343.68 ± 78.89, and 452.83 ± 90.27 ng/mL in sows receiving 0.5, 1.0, 1.5, and 2.0 mg/kg firocoxib, respectively, and 9.53 ± 1.21, 31.04 ± 6.79, 53.30 ± 11.1, and 44.03 ± 7.47 ng/mL in their respective piglets. Mean plasma terminal half-life values ranged from 26 to 31 h in sows and 30 to 48 h in piglets. Barrows nursing sows that received 2.0 mg/kg firocoxib had a lower mean plasma cortisol concentration at 1 ± 1 h after processing compared with barrows nursing sows that received 1.0 mg/kg (P = 0.0416) and 0.5 mg/kg of firocoxib (P = 0.0397). From processing to weaning, litters of sows receiving 2.0 mg/kg firocoxib gained more weight than litters of sows that received 0.5 mg/kg (P = 0.008) or 1.0 mg/kg (P = 0.005). No signs of nonsteroidal anti-inflammatory drug toxicity were observed on examination of the kidney, liver, stomach, and small intestine, and concentrations of firocoxib and the descyclopropylmethyl metabolite were below the limit of detection (0.01 µg/g) in all tissues examined from sows and piglets. These findings indicate that maternal delivery of firocoxib to suckling piglets before tail docking and castration may safely reduce processing-induced stress and enhance production by increasing weaning weights., (© The Author(s) 2019. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

To predict the laser ablation profile on dental hard tissue which will enable the user to optimize laser parameters so as to carry out the laser treatment with minimal tissue damage. The present study constructs a mathematical model to predict the ablation profile based on Gaussian beam distribution of laser intensity and correlates the model with experimentally obtained ablation parameters (effective Gaussian beam radius, ablation threshold fluence, and effective energy penetration depth). To obtain the ablation parameters, laser ablation experiments were carried out on dental hard tissues using Ti:Sapphire femtosecond laser (800 nm, 100 fs, 10 kHz). The method is further extended to predict the ablation rate and efficiency as well. The profile predicted from the mathematical model is compared with that of experimental results. It is found that the predicted ablation profile agrees well with the experimental profile for both enamel and dentin except a slight deviation at higher fluence for dentin. The calculated ablation rate is comparable to that of experimental results whereas for ablation efficiency appreciable deviation is observed in the case of dentin. The model succinctly predicts the ablation profile, ablation rate, and ablation efficiency which will enable to perform dental surgery at optimized laser processing conditions with high precision thus reducing the tissue damage appreciably. Once the details of lesion are known through proper diagnostic tools, the method enables the user to readily obtain optimum laser parameters. It can be used as a handy reference for dentists to perform damage-free surgery, ensuring quicker healing.

The replacement of one tooth using one implant involves a set of unique criteria for long-term success. Successful therapy should be based on long-term function and health of the adjacent tissues. Sections of this article examine these critical criteria that when working together can result in successful long-term tooth replacement., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: In dentistry, dentists perform many treatments with a few visually magnified information. About deep area of root canals, it commonly relies on exploration carried out with the fingers of the dentist, because the root canal entrance is very small to be observed. In clinical practice, the intraoral camera and endoscopic systems are separate devices, and there are no sensors to capture both pictures of the whole tooth and those inside the root canal. Objective of this research is to combine the intraoral camera and endoscopic system facilitating to use clinical practice., Methods: We propose an endoscopic system based on the thin image fiber, SOPROLIFE intraoral camera as an image sensor, and a new adaptor to connect the two parts. We observed resolution charts with 50, 25, 10, and 5 line pairs (LP)/mm patterns. The acquired images are processed to both remove fixed-pattern noise using robust principal component analysis and enhance contrast., Results: The acquired images containing all LP/mm patterns were clear and showed higher contrast after processing. Visibility of the processed images is 1.7, 1.6, 2.2, and 1.9 times higher than that of the raw images for 50, 25, 10, and 5 LP/mm patterns, respectively., Conclusion: Our fabricated endoscopic system based on the SOPROLIFE intraoral camera could observe 50, 25, 10, and 5 LP/mm patterns. After image processing, the noise was reduced, and high-contrast images were obtained., Significance: This system can be considered as a further step toward facilitating noninvasive and contactless systems in clinical practice.

Introduction: Partial pulpotomy is a vital treatment for carious and traumatic exposure, especially in young permanent teeth. Cell-based therapy for partially pulpotomized teeth can be considered a promising approach for dentin-pulp complex regeneration. This study evaluated the healing capacity of autologous bone marrow-derived stem cells (BMSCs) on partially pulpotomized teeth in a dog model., Methods: Twelve mongrel dogs were selected, and a total number of 192 posterior mandibular and maxillary teeth were involved in the study (16 teeth per dog). Partial pulpotomies were performed, and the dogs were assigned into 2 equal groups (groups 1 and 2), 6 dogs in each group. The coronal pulp cavities (n = 96) of group 1 were filled with calcium silicate-based capping material. Group 2 coronal pulp cavities (n = 96) were seeded with 1 × 105 cell/mL BMSCs, and then the cavities were filled with calcium silicate-based capping material. After placing the capping materials, the cavities of both groups (1 and 2) were filled with resin-modified glass ionomer restorative material. From each group, 48 teeth from 3 dogs were evaluated histologically after 1 week, and the other 48 teeth from the remaining 3 dogs were evaluated after 9 weeks. Scoring was done for the amount of inflammatory cell infiltrates, tissue necrosis, and thickness of hard tissue bridge formation., Results: The Mann-Whitney U statistical test performed for hard tissue bridge formation revealed significant differences between the 2 groups at the 1- (P < .05) and 9-week (P < .05) examination periods., Conclusions: Autologous BMSCs have significant therapeutic potential because they enhance the healing capacity of partially pulpotomized dogs' teeth., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Dental esthetics need to be defined from the scientific perspective in order to obtain predictable treatment outcomes and avoid the effects of subjectivisms on the part of the dental profesional. It can be deduced that the ideal dimensions in the maxillary anterior sector are difficult to establish. Therefore, the primary purpose of this study was to define the dimensions of the maxillary anterior teeth and the relationships between them. In addition, an analysis was made to reinvestigate whether they complied with the Golden proportion, the RED (Recurrent Esthetic Dental) proportion and the Golden percentage. A total of 2304 tooth corresponding to 384 subjects were evaluated. The central incisor presented a mean width of 8.58 mm and a height of 9.35 mm, while the lateral incisor presented a width of 6.69 mm and a height of 7.75 mm. The mean width of the canine was 7.69 mm, with a height of 8.68 mm. The teeth revisited in this study did not comply with the ideal dimensions in the anterior maxillary sector as established by the Golden proportion, Golden percentage and RED. The information obtained from this study can be clinically applied to restore the dimensions during periodontal surgery, restorative dentistry and prosthetic rehabilitation.

Preoperative planning in dentistry relies on imaging to assess the separation between the teeth and mandibular canal. Cone beam CT(CBCT) shows inferior contrast of the mandible canal and features radiation. In this work, the use of zero TE (zTE) imaging as an alternative to CBCT imaging for preoperative planning in dentistry is investigated. Twenty-two patients (11 males, 11 females, age 26-65) were enrolled in this prospective study. The performance of zTE imaging was assessed using CBCT as a gold standard in preoperative planning for tooth extraction (qualitative classification) and implanting (quantitative dimensional measurement). Zero TE imaging showed clear delineation of teeth and mandible, and showed better depiction of the mandible canal as compared to CBCT. In assessing the spatial relationship between the third molar and the mandibular canal, identical results were obtained from two readers based on zTE and CBCT images; in spatial measurements related to the second premolar, high intraclass coefficient was obtained in all the performed measurements between zTE and CBCT (0.782 to 0.921) and between reviewers (0.812 to 0.958). The results of Bland Altman analysis also indicated low level of bias (max -1.8%) and disagreements (max -15.1% to 11.3%) between the results of zTE and CBCT. Zero TE imaging may be a potential imaging tool in preoperative planning in dentistry when CBCT is undesirable., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The objectives of this study were to determine the quantitative changes after different ridge preservation techniques (primary aim) and to assess the possibility of placing a dental implant, the bone quality, and the need for bone augmentation (secondary aim). A total of 35 patients who required extraction of at least one tooth (incisor, canine, or premolar) provided 35 single-gap extraction sites. After minimally invasive tooth removal, the sockets were randomly scheduled for one of four treatment modalities: placement of a deproteinized bovine bone mineral (DBBM; Endobon, Biomet 3i) covered with a soft tissue punch from the palate (T1); placement of DBBM alone (T2); placement of DBBM covered with a resorbable collagen membrane (OsseoGuard, Biomet 3i) (T3); or no additional treatment (T4). Silicone impressions were taken before and 6 months after extraction for quantitative-volumetric evaluation (primary outcome). The possibility of placing an implant, bone quality, and need for further bone augmentation were also noted (secondary outcomes). During the study period, no adverse events were observed. No statistically significant difference was found between the four treatments regarding the primary and secondary outcome parameters (P > .05). However, T4 showed double the buccal contour change, with the highest variance compared to the other three groups (T1 -0.874 ± 0.713; T2 -0.968 ± 0.344; T3 -1.26 ± 0.942; T4 -2.15 ± 1.349). Although no statistically significant difference was found between the four treatment modalities, placement of DBBM resulted in only half the contour change (< 1 mm) compared to control sites (> 2 mm). Ridge preservation with a DBBM with or without soft tissue punch should be considered in esthetically demanding cases and delayed or late implant placement.

Chronic rhinosinusitis (CRS) may arise due to odontogenic etiologies. However, it is unknown whether odontogenic CRS has a differential impact on patients' quality of life (QOL) compared to standard, inflammatory (but non-odontogenic) CRS. The objective of this study was to determine whether there is a difference in the impact of sinonasal symptomatology on general health-related QOL in odontogenic CRS compared to non-odontogenic CRS. This was a retrospective review of 21 odontogenic CRS patients who visited our tertiary care center. The severity of sinonasal symptomatology and CRS-specific QOL detriment was measured using the 22-item Sinonasal Outcomes Test (SNOT-22) and general health-related QOL was measured using the health utility index from the 5-item EuroQol survey (EQ-5D HUV). Compared to non-odontogenic CRS, odontogenic CRS was not associated with a difference in SNOT-22 score [linear regression coefficient (β) = - 1.57, 95% CI - 12.47 to 9.32, p = 0.777] but was significantly associated with decreased EQ-5D HUV (β = - 0.10, 95% CI - 0.17 to - 0.03, p = 0.008). We also found that the magnitude of association (β) between SNOT-22 and EQ5D-HUV was greater for odontogenic CRS patients compared to non-odontogenic CRS patients (p = 0.045). Our findings suggest sinonasal symptoms may have a greater impact on general QOL in odontogenic CRS compared to non-odontogenic CRS. The reason for this remains unknown, but deserves further study.

Introduction: Smile aesthetics is based on numerical, physical, physiological and psychological data regarding beauty, while taking into account the desires of the patient. It is determined by the shape, colour and position of the lips, teeth and gingival tissues. Periodontal examination in both the facial and labial settings supports analysis of the gingival display during natural and forced smiling, the health of the periodontium, the gingival contours, the aesthetic gingival line, and the presence of the papillae., Materials and Methods: All these data will help establish a gingival aesthetic score to determine the causes of disharmony and possible treatment., Discussion: During implementation of the global orthodontic treatment plan, periodontal plastic surgery can change the gingival appearance and morphology in order to restore the harmony of the smile. Subtractive periodontal plastic surgery treats biological space defects and excess tissue during incomplete passive eruption by gingivectomy or apically positioned flap, combined, or not, with osteoplasty or osteoectomy. Finally, injections of hyaluronic acid in the papillae can plump them up and minimize the size of any black holes., (© EDP Sciences, SFODF, 2018.)

Exodontia is a cardinal skill of all dentists. Patients expect extractions to be skillfully and painlessly accomplished every time. It's not necessarily so simple and can be challenging. In this paper we explore contemporary issues of the full process of exodontia including diagnosis, technique, complication minimization as well as management of medically compromised patients with appropriate post-operative care, including pharmacotherapy., (© 2018 Australian Dental Association.)

Cone beam computed tomography (CBCT) has obvious advantages over regular radiography in diagnosis of complex diseases. Objective of this study is to report a case of a mandibular jaw ameloblastoma recurring cyst, which represents a benign tumor of odontogenic epithelium, using CBCT imaging technology. CBCT examination of the patient suffering with recurrent lower jaw cyst (relapsing four years after surgery) showed a decrease in irregular bone density and appearance of a honeycomb pattern (3.5 cm×2.5 cm×1.8 cm) in the right lower jaw. This suggests that the lesion is more likely to be an ameloblastoma. Preoperative tissue biopsy and pathological examination of surgical sample confirmed the diagnosis. Surgical resection of the diseased tissue and autogenous bone grafting in the mandible was performed. Postoperative CBCT examination showed that the bone defect healed well, without recurrence of the tumor 22 months postoperatively. In conclusion, the rotated 3D CBCT images clearly displays the exact size, location, borders and internal changes of the tumor in the jaw cyst itself and the adjacent tissues. Thus, the dental CBCT allows clinicians to better evaluate lesions, leading to better treatment outcomes.

An ex-vivo study was performed on vertically mounted equine maxillary cheek teeth that had caries of 30 infundibulae, using high and low speed contra-angle dental drills and Hedstrom files to debride infundibular food debris and carious dental tissues. This technique effectively debrided 27/30 infundibulae with a mean depth of 19mm (range 9.4-34.3mm) as assessed by computed tomographic (CT) imaging. The debrided infundibulae were treated with sodium hypochlorite, EDTA and a bonding agent, and then then filled in layers with endodontic restoration materials. Further CT imaging and direct examination of sectioned restored teeth showed 6/30 infundibulae, including three that were incompletely debrided, to have defects between the restoration and the infundibular wall/apex. Twenty-one of the remaining 24 infundibulae contained air bubbles, largely within restorations. It is concluded that the use of drills and Hedstrom files is effective in debriding carious infundibulae but improved techniques and materials are required to more effectively fill infundibulae with restorative material., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objective: The purpose of this study is to assemble a laser system for the selective removal of dental composite from tooth surfaces, that is feasible for clinical use incorporating a spectral feedback system, a scanning system, articulating arm and a clinical hand-piece, and evaluate the performance of that system on extracted teeth., Methods: Ten extracted teeth were collected and small fillings were placed on the occlusal surface of each tooth. A clinical system featuring a CO 2 laser operating at 50 Hz and spectral optical feedback was used to remove the composite. Removal was confirmed using a cross polarized optical coherence tomography (CP-OCT) system designed for clinical use., Results: The system was capable of rapidly removing composite from small preparations on tooth occlusal surfaces with a mean loss of enamel of less than 20 μm., Conclusion: We have demonstrated that spectral feedback can be successfully employed in an automated system for composite removal by incorporating dual photodiodes and a galvanometer controlled CO 2 laser. Additionally, the use of registered OCT images presents as a viable method for volumetric benchmarking. Overall, this study represents the first implementation of spectral feedback into a clinical hand-piece and serves as a benchmark for a future clinical study. Lasers Surg. Med. 49:658-665, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Mini dental implants (MDI) were once thought of as transitional implants for treatment in selected clinical situations. Their reduced diameter makes them a very attractive option for patients with poor tolerance to maxillary and mandibular prostheses. Using the method of finite element analysis, a series of different designed MDI prototypes have been investigated. The prototypes differed in the geometry of implant body and/or design of implant head. The load transfer of the implant prototypes to the idealised alveolar bone has been regarded and the prototypes have been compared to each other and to a number of standard commercial implants. The prototype models have been virtually placed in the idealised bone with a cortical thickness of 1.5 mm and loaded laterally 30° from the implant's long axis. The condition of immediate loading was assumed for the numerical analyses through defining a contact interface between the implant and bone bed. The numerical analysis in this study showed that the design of the investigated prototype MDI of group 3 (mini-ball head) is the most advantageous design.

The autogenous tooth transplantation approach to replace missing teeth has been in use for a long time. Different surgical techniques have been developed to improve prognosis and longevity of transplanted teeth with complete root formation. Many factors reportedly affected short- and long-term success of the procedure: complications such as ankylosis and root resorption up to the tooth exfoliation have occurred frequently. Several studies have appeared on this issue over the years. However, outcomes of transplantations have not yet been conclusively determined as no randomized clinical trials have been published on this issue, and their effectiveness has been evaluated only in observational studies. On the other hand, interesting information from specific experimental studies on the healing pattern of the interface between the root surface and alveolar bone in the replantation/transplantation model, and from non-related studies dealing with mechanically induced periodontal trauma, has been available and potentially useful since the 1970s to 1980s. However, this information has not been incorporated into clinical literature regarding tooth autotransplantation. This commentary aims to show how information from related and unrelated experimental models was translated to a clinical setting and led to a novel approach, successfully applied, in the autotransplantation of a multirooted tooth with completed root formation.

Background: Experiments have previously demonstrated the therapeutic potential of mobilized dental pulp stem cells (MDPSCs) for complete pulp regeneration. The aim of the present pilot clinical study is to assess the safety, potential efficacy, and feasibility of autologous transplantation of MDPSCs in pulpectomized teeth., Methods: Five patients with irreversible pulpitis were enrolled and monitored for up to 24 weeks following MDPSC transplantation. The MDPSCs were isolated from discarded teeth and expanded based on good manufacturing practice (GMP). The quality of the MDPSCs at passages 9 or 10 was ascertained by karyotype analyses. The MDPSCs were transplanted with granulocyte colony-stimulating factor (G-CSF) in atelocollagen into pulpectomized teeth., Results: The clinical and laboratory evaluations demonstrated no adverse events or toxicity. The electric pulp test (EPT) of the pulp at 4 weeks demonstrated a robust positive response. The signal intensity of magnetic resonance imaging (MRI) of the regenerated tissue in the root canal after 24 weeks was similar to that of normal dental pulp in the untreated control. Finally, cone beam computed tomography demonstrated functional dentin formation in three of the five patients., Conclusions: Human MDPSCs are safe and efficacious for complete pulp regeneration in humans in this pilot clinical study.

Objective: To explore a new method for rapid extracting and rebuilding three-dimensional (3D) digital root model of vivo tooth from cone beam computed tomography (CBCT) data based on the anatomical characteristics of periodontal ligament, and to evaluate the extraction accuracy of the method., Methods: In the study, 15 extracted teeth (11 with single root, 4 with double roots) were collected from oral clinic and 3D digital root models of each tooth were obtained by 3D dental scanner with a high accuracy 0.02 mm in STL format. CBCT data for each patient were acquired before tooth extraction, DICOM data with a voxel size 0.3 mm were input to Mimics 18.0 software. Segmentation, Morphology operations, Boolean operations and Smart expanded function in Mimics software were used to edit teeth, bone and periodontal ligament threshold mask, and root threshold mask were automatically acquired after a series of mask operations. 3D digital root models were extracted in STL format finally. 3D morphology deviation between the extracted root models and corresponding vivo root models were compared in Geomagic Studio 2012 software. The 3D size errors in long axis, bucco-lingual direction and mesio-distal direction were also calculated., Results: The average value of the 3D morphology deviation for 15 roots by calculating Root Mean Square (RMS) value was 0.22 mm, the average size errors in the mesio-distal direction, the bucco-lingual direction and the long axis were 0.46 mm, 0.36 mm and -0.68 mm separately. The average time of this new method for extracting single root was about 2-3 min. It could meet the accuracy requirement of the root 3D reconstruction fororal clinical use., Conclusion: This study established a new method for rapid extracting 3D root model of vivo tooth from CBCT data. It could simplify the traditional manual operation and improve the efficiency and automation of single root extraction. The strategy of this method for complete dentition extraction needs further research.

Aim: The purpose of this study was to investigate the sealing ability of three different resin cements for the luting of a porcelain laminate veneer (PLV) to the enamel and dentin of fluorosed teeth., Materials and Method: Thirty incisors with moderate fluorosis according to the Thylstrup-Fejerskov Index (TFI = 4 to 6) received a veneer preparation with dentin margins at the gingival third. The IPS Empress (Ivoclar Vivadent) veneers were luted to the teeth of three groups (n = 10) using three different resin cements: Group 1: Excite DSC/Variolink II - etch-and-rinse (E&R), Group 2: ED Primer II/Clearfil Esthetic - self-etch (SE), Group 3: RelyX Unicem - self-adhesive (SA). After 24 h of water storage and thermocycling, marginal microleakage was evaluated on three slices from each tooth using the dye penetration technique under a digital microscope., Results: Data (microleakage percentage over the entire preparation length) were analyzed using the Kruskal-Wallis and Mann-Whitney tests (P < 0.05). Mean microleakage percentage was 0.8% to 18% at the enamel and dentin margins, respectively. On the enamel, Group 1 (E&R) exhibited significantly less microleakage compared to Groups 2 (SE; P = 0.03), and 3 (SA; P = 0.005). On the dentin, microleakage in Group 3 (SA) was significantly less than that in Groups 1 (E&R, P = 0.001), and 2 (SE; P = 0.03). The difference between the latter two groups was significant, with Group 1 (E&R) exhibiting the greatest microleakage., Conclusion: The best enamel and dentin sealing of the cemented veneers was obtained with the E&R and SA luting agents, respectively.

When treating the color of a single tooth in the esthetic zone, it is a complex task to achieve the same visual effect as the rest of the teeth. In addition to the problem of the clinical crown color, if the patient has a thin periodontal biotype it is necessary to manipulate both the hard and soft tissue to achieve a good esthetic result. To change the biotype, a connective tissue graft needs to be performed. The graft must be stabilized exactly where it is needed, and the recipient area modified. The tooth needs to receive an adequate preparation so as to make the restoration thick enough to naturally mask the treated tooth, while also ensuring long-term stability.

The reported failure rate for full veneer crowns of canine teeth of dogs is suboptimal, particularly in teeth with naturally poor retentive features, such as those with low height/diameter (H/D) ratios or high convergence angles (CAs). The objective of the present study was to evaluate the application of axial grooves in an effort to develop a crown preparation design that enhances the retention of full veneer crowns in dogs. Crown dislodgment testing was performed on cast alloy dies of canine teeth with unfavorable retention features (low H/D and high CA) prepared with (n = 14) and without axial grooves (n = 15) to evaluate the force required to dislodge a cemented full veneer crown. The crown/die units were secured within a universal testing machine and a load was applied at the 45° oblique direction from distal to mesial to replicate the vector encountered during biting-pulling action. The maximum force required to cause crown dislodgment was recorded for each crown. Statistical analysis revealed a significant increase in force required for crown dislodgment when axial grooves were included in the crown preparation design ( P < .001). Crown retention is improved in canine teeth with otherwise poor retention features when axial grooves are made in the labial and palatal/lingual walls during crown preparation.

Purpose: The aim of this study was to evaluate the fracture resistance of fatigued lithium disilicate pressed zirconia crowns versus other ceramic crowns., Materials and Methods: Lithium disilicate pressed zirconia, fluorapatite pressed zirconia, monolithic lithium disilicate, and monolithic zirconia crowns were fabricated. Cyclic and static loadings were applied to the mesiobuccal cusp tip after thermocycling and fracture strengths were recorded., Results: Fatigued lithium disilicate pressed zirconia crowns were found to have a fracture resistance of 9,117.81 ± 727.04 N, compared with 9,240.61 ± 887.21 N for monolithic zirconia crowns, 3,030.18 ± 1,505.83 N for fluorapatite pressed zirconia crowns, and 4,173.94 ± 877.46 N for monolithic lithium disilicate crowns (P = .001)., Conclusion: This in vitro study shows that fatigued lithium disilicate pressed zirconia and monolithic zirconia crowns have better fracture resistance than fluorapatite pressed zirconia and monolithic lithium disilicate crowns.