Dentoskeletal and soft tissue changes associated with miniscrew anchorage in customized lingual orthodontics.

OBJECTIVES: The goal of this study was to analyze skeletal, dental, and soft tissue changes of patients treated with customized lingual systems and to evaluate the clinical effectiveness of miniscrew anchorage. METHODS: Nine upper first premolar extraction patients who were treated with customized lingual appliances were included in this study. Miniscrews were used for reinforcement of molar anchorage. Cephalometric films and study models were obtained before treatment (T1), after alignment (T2), and after treatment (T3). Treatment effects were analyzed by cephalometric radiographs and study models. RESULTS: The upper anterior teeth were retracted significantly at T2 and T3 (4.41 ± 4.14 mm and 5.51 ± 2.48 mm, respectively). During space closure, the upper first molars showed slight mesial movement (1.50 ± 1.97 mm). The intercanine width of the upper arch increased at T2 (1.59 ± 1.81 mm), but decreased at T3 (0.11 ± 1.00 mm). The sella-nasion-A, A-nasion-B, and mandibular plane angles were not significantly changed at T3. The upper lip showed continuous retraction at both T2 and T3 (1.40 ± 1.46 mm and 2.32 ± 2.48 mm, respectively). CONCLUSIONS: By using miniscrew anchorage for lingual orthodontics, patients' dental and soft tissue changes considerably improved and molar anchorage was reinforced.

Development and evaluation of the Jönköping Dental Fear Coping Model: a health professional perspective.

OBJECTIVE: The purpose of this study was to design a structured treatment model focusing on all levels of adult's dental fear, the Jönköping Dental Fear Coping Model (DFCM). The aim was to study the DFCM from a dental health professional perspective. MATERIAL AND METHODS: The DFCM was studied by means of quantitative and qualitative analyses. Nine dental clinics participated in Period I (pre-intervention/standard care), and 133 dental health professionals (dentists, dental hygienists, dental assistants) and 3088 patients were included. After completion of Period I, four of the clinics were randomized to Period II (intervention), beginning with the professionals undergoing DFCM training. Following that, 51 dental health professionals treated 1417 patients according to the DFCM. The other five clinics served as controls. RESULTS: Half or more of the dental health professionals assessed the model as better than standard care, regarding anamnesis and diagnostics, communication and contact, and understanding of patients and dental fear. The dental health professionals reported higher tension in their fearful patients in Period II compared with Period I, possibly due to their increased awareness of dental fear. CONCLUSIONS: The qualitative data suggest that dental health professionals find the DFCM beneficial in routine dental care. The model promotes a holistic approach to the treatment of adult patients. However, stress among the professionals was not reduced when measured, neither quantitatively nor qualitatively. It is important to evaluate the model in further studies to make it possible to draw generalizable conclusions.

Dynamic Irrigation Promotes Apical Papilla Cell Attachment in an Ex Vivo Immature Root Canal Model.

INTRODUCTION: The use of dentin preconditioning techniques in regenerative endodontic procedures is currently promising. Several growth factors have been detected on dentin after ultrasonic irrigation with EDTA. This study aimed to evaluate the effects of dynamic irrigation with different solution regimens on apical papilla cell (APC) attachment in an ex vivo immature tooth model. METHODS: Various dynamic irrigation techniques, needle irrigation (NI), NI with EndoActivator, and NI with passive ultrasonic irrigation, were used with different solution regimens, normal saline solution (NSS), EDTA, and chlorhexidine digluconate followed by EDTA, in enlarged root canal models where calcium hydroxide-medicated dentin slices were inserted. The initial number of attached fibronectin-positive APCs was counted. Dentin surface morphology was also inspected by using scanning electron microscopy. RESULTS: The number of APCs was significantly greater in the dynamic irrigation groups than in the control group (P < .001). Greater APC numbers were observed in the groups in which NSS was used than in those in which EDTA or chlorhexidine digluconate/EDTA was used, when using the same techniques (P < .001). Cell numbers were similar at all levels of the root canals; however, in the ultrasonically supplemented group irrigated with NSS, the number of attached cells was significantly increased at the middle and apical levels (P < .05). CONCLUSIONS: The use of dynamic irrigation techniques in an immature tooth model definitely promoted APC attachment to calcium hydroxide-medicated dentin. Furthermore, when NSS was used as a final irrigant, the number of attached cells was significantly increased.

The "index cutback technique": a three-dimensional guided layering approach in direct class IV composite restorations.

One of the main difficulties encountered with conventional class IV direct composite restorations is the layering management in terms of three-dimensionality and shape control. The major concern is the predictability of the esthetic outcome, which is closely linked to the clinician's skills. This article presents a predictable approach to treat class IV direct composite restorations. The technique allows for the shape and thickness of different composite layers to be guided through transparent indexes that have been carried out previously on a planned wax-up. The final goal is to achieve a good esthetic outcome in an easy and fast way through a copy-and-paste approach. The "index cutback technique" is a complementary variant of the "index technique" for class IV direct restorations. After the casts have been generated, the technician creates a full wax-up of the tooth to be restored. A transparent silicone key of the full wax-up provides the full enamel index that is then cut with a blade along the incisal edge to achieve two enamel indexes, one palatal and one buccal. Then, the required amount of wax is removed from the full wax-up through a cutback step. The aim of this step is to remove a suitable amount of wax to leave a predetermined space for the composite enamel layers, both on the palatal and buccal surfaces. A second transparent silicone key is built on the cutback wax-up to achieve the cutback dentin index, which is then used to press the composite dentin onto the prepared tooth.

Evaluation of physicochemical properties of root-end filling materials using conventional and Micro-CT tests.

OBJECTIVE: To evaluate solubility, dimensional stability, filling ability and volumetric change of root-end filling materials using conventional tests and new Micro-CT-based methods. MATERIAL AND METHODS: 7. RESULTS: The results suggested correlated or complementary data between the proposed tests. At 7 days, BIO showed higher solubility and at 30 days, showed higher volumetric change in comparison with MTA (p<0.05). With regard to volumetric change, the tested materials were similar (p>0.05) at 7 days. At 30 days, they presented similar solubility. BIO and MTA showed higher dimensional stability than ZOE (p<0.05). ZOE and BIO showed higher filling ability (p<0.05). CONCLUSIONS: ZOE presented a higher dimensional change, and BIO had greater solubility after 7 days. BIO presented filling ability and dimensional stability, but greater volumetric change than MTA after 30 days. Micro-CT can provide important data on the physicochemical properties of materials complementing conventional tests.

Evaluation of physicochemical properties of root-end filling materials using conventional and Micro-CT tests

Abstract Objective To evaluate solubility, dimensional stability, filling ability and volumetric change of root-end filling materials using conventional tests and new Micro-CT-based methods. Material and Methods Solubility (loss of mass) after 7 and 30 days, and dimensional stability (in mm) were evaluated in accordance with Carvalho-Junior, et al. 7 (2007). The filling ability and volumetric change (in mm3) were evaluated by Micro-CT (Bruker-MicroCT, Kontich, Belgium) using resin models with cavities 3 mm deep and 1 mm in diameter. The cavities were filled with materials to evaluate filling ability, and then scanned by Micro-CT. After 7 and 30 days immersed in distilled water, the filled cavities were scanned again to evaluate the volumetric change. MTA Angelus (MTA), Biodentine (BIO) and zinc oxide-eugenol cement (ZOE) were evaluated. Data were submitted to analysis of variance (ANOVA) and Tukey's test with 5% significance level. Results The results suggested correlated or complementary data between the proposed tests. At 7 days, BIO showed higher solubility and at 30 days, showed higher volumetric change in comparison with MTA (p<0.05). With regard to volumetric change, the tested materials were similar (p>0.05) at 7 days. At 30 days, they presented similar solubility. BIO and MTA showed higher dimensional stability than ZOE (p<0.05). ZOE and BIO showed higher filling ability (p<0.05). Conclusions ZOE presented a higher dimensional change, and BIO had greater solubility after 7 days. BIO presented filling ability and dimensional stability, but greater volumetric change than MTA after 30 days. Micro-CT can provide important data on the physicochemical properties of materials complementing conventional tests.

Rotating and translating anthropomorphic head voxel models to establish an horizontal Frankfort plane for dental CBCT Monte Carlo simulations: a dose comparison study.

In order to carry out Monte Carlo (MC) dosimetry studies, voxel phantoms, modeling human anatomy, and organ-based segmentation of CT image data sets are applied to simulation frameworks. The resulting voxel phantoms preserve patient CT acquisition geometry; in the case of head voxel models built upon head CT images, the head support with which CT scanners are equipped introduces an inclination to the head, and hence to the head voxel model. In dental cone beam CT (CBCT) imaging, patients are always positioned in such a way that the Frankfort line is horizontal, implying that there is no head inclination. The orientation of the head is important, as it influences the distance of critical radiosensitive organs like the thyroid and the esophagus from the x-ray tube. This work aims to propose a procedure to adjust head voxel phantom orientation, and to investigate the impact of head inclination on organ doses in dental CBCT MC dosimetry studies. The female adult ICRP, and three in-house-built paediatric voxel phantoms were in this study. An EGSnrc MC framework was employed to simulate two commonly used protocols; a Morita Accuitomo 170 dental CBCT scanner (FOVs: 60 × 60 mm2 and 80 × 80 mm2, standard resolution), and a 3D Teeth protocol (FOV: 100 × 90 mm2) in a Planmeca Promax 3D MAX scanner. Result analysis revealed large absorbed organ dose differences in radiosensitive organs between the original and the geometrically corrected voxel models of this study, ranging from -45.6% to 39.3%. Therefore, accurate dental CBCT MC dose calculations require geometrical adjustments to be applied to head voxel models.

[Dental 3d level simulators in the study of local anesthesia]. / Opyt ispol'zovaniya simulyatorov 3 urovnya realistichnosti v stomatologii na primere izucheniya metodov provodnikovogo obezbolivaniya.

The purpose of the study was to develop a training protocol for local anesthesia in dental students. The study involved 90 2d year dental school students divided into 3 groups according to procedure training method: on skeletal preparations; by «Typodont¼ simulator and by combination of methods. Manipulation effectiveness criteria in skeletal preparations was penetrating the mandibular foramina by isolation of the corresponding region by latex scarf. In «Typodont¼ the effective injection was determined by light and sound signals. The results showed the necessity for combined approach as it gives an opportunity to identify mandible foramina by projecting on soft tissue marks with further skills developing on the simulator. When using the combined approach only 4 students successfully completed their task by initial injection while at the second attempt only 4 were not successful.

Mandibular and dental characteristics of Late Triassic mammaliaform Haramiyavia and their ramifications for basal mammal evolution.

As one of the earliest-known mammaliaforms, Haramiyavia clemmenseni from the Rhaetic (Late Triassic) of East Greenland has held an important place in understanding the timing of the earliest radiation of the group. Reanalysis of the type specimen using high-resolution computed tomography (CT) has revealed new details, such as the presence of the dentary condyle of the mammalian jaw hinge and the postdentary trough for mandibular attachment of the middle ear-a transitional condition of the predecessors to crown Mammalia. Our tests of competing phylogenetic hypotheses with these new data show that Late Triassic haramiyids are a separate clade from multituberculate mammals and are excluded from the Mammalia. Consequently, hypotheses of a Late Triassic diversification of the Mammalia that depend on multituberculate affinities of haramiyidans are rejected. Scanning electron microscopy study of tooth-wear facets and kinematic functional simulation of occlusion with virtual 3D models from CT scans confirm that Haramiyavia had a major orthal occlusion with the tallest lingual cusp of the lower molars occluding into the lingual embrasure of the upper molars, followed by a short palinal movement along the cusp rows alternating between upper and lower molars. This movement differs from the minimal orthal but extensive palinal occlusal movement of multituberculate mammals, which previously were regarded as relatives of haramiyidans. The disparity of tooth morphology and the diversity of dental functions of haramiyids and their contemporary mammaliaforms suggest that dietary diversification is a major factor in the earliest mammaliaform evolution.

Planning and predictability of clinical outcomes in esthetic rehabilitation.

In esthetic rehabilitation, it is a challenge to meet the needs of patients with growing expectations. Creating predictable results is the key to success. This can be accomplished by performing a comprehensive esthetic diagnosis, elaborating treatment proposals that satisfy today's esthetic standards, and using modern computer-assisted methods. The diagnostic wax-up and mock-up are effective tools that allow patients to visualize treatment proposals without invasive procedures. Once the patient has approved the proposals, they provide the basis for the fabrication of the final restoration. The use of modern ceramic materials makes it possible to achieve a good esthetic outcome, even in restorations with extremely thin layer thicknesses. Esthetic cementation is the final step of restorative treatment.

A pilot study on spatial changes in the maxilla caused by osteopathic therapy.

OBJECTIVES: A variety of theories on the pathogenesis of temporomandibular disorders (TMD) exists resulting in treatment approaches ranging from the fabrication of occlusal splints to alternative treatment modalities such as osteopathy. The goal of this pilot study was to investigate whether osteopathic treatment causes spatial changes in the maxilla. METHOD AND MATERIALS: Following ethics commission approval and informed patient consent, three patients diagnosed with TMD participated in this investigation. In addition to regular treatment, an individualized mandibular occlusal splint was fabricated and a maxillary silicone impression was made. Following osteopathic treatment, the splint was adapted intraorally and another maxillary impression was made. Before and after treatment, the splint and the impressions were scanned three-dimensionally. The resulting images were superimposed using best-fit matching algorithms. RESULTS: Inconsistent spatial changes in the posterior areas were observed both in the maxillary impressions as well as in the mandibular splints reaching maximum absolute values of 0.50 mm. CONCLUSION: Based on this pilot study, it appears that osteopathic treatment may be capable of inducing spatial changes in the maxilla due to sutural movement thereby validating the fundamental principles of osteopathic treatment. Although, based on the study conducted, it cannot be concluded that osteopathy constitutes a successful treatment alternative in TMD patients, practitioners should be aware of this treatment modality.

Variation of orthodontic treatment decision-making based on dental model type: A systematic review.

OBJECTIVE: To determine in which clinical scenarios digital models are valid as replacements for plaster models during orthodontic treatment decision-making process and treatment planning. MATERIALS AND METHODS: An attempt to identify all pertinent published information was made. Retained articles were those where a decision-making process leading to differential orthodontic treatment plans based on either method were compared. The search was tailored for PubMed and adapted for EMBASE, MEDLINE, the Cochrane Library, LILACS, and Web of Science. A partial grey literature search was conducted through Google Scholar. References lists of the included articles were screened for potential relevant studies. The methodology of selected studies was evaluated using the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS). RESULTS: Only two studies were finally selected for the qualitative and quantitative synthesis. QUADAS results scores from selected studies ranged from 61% to 83% of 11 items evaluated. In one, the overall treatment plan regarding orthognathic surgery for Class II malocclusion changed in 13% to 22% of the cases. In the other one, 6% of the orthodontic treatment plans changed. CONCLUSION: Digital models could be used to replace plaster models in Class II malocclusion treatment planning.

A cusp supporting framework design can decrease critical stresses in veneered molar crowns.

OBJECTIVES: Veneered zirconia restorations predominately fail due to veneering fractures. It is hypothesized that a cusp-supporting framework design can prevent these catastrophic failures in all-ceramic restorations. Therefore, we investigated the influence of framework design and framework material on the stress distribution in a single tooth restoration using the numerical finite element method. METHODS: A three-dimensional model of a veneered lower molar (36) crown with constant outer shape was used. The framework design was either cusp supporting or with a constant framework thickness. Zirconia, alumina, and a gold alloy were used as framework material. A glass ceramic material was used as veneering material for both cases. Two different load cases were simulated: terminal occlusion with load distributed over the occlusal surface of the tooth and a fairly extreme load case with all force concentrated on one cusp. RESULTS: Maximum tensile stresses in the glass ceramic veneering material concentrated in the fissure region for all models. A cusp supporting framework design decreased the maximum tensile stresses significantly up to 30.5%. The distolingual load case resulted in an approximately fourfold higher stress level compared to the terminal occlusion load case. SIGNIFICANCE: A cusp supporting framework design can significantly decrease the maximum tensile stresses in the veneering material of single crowns. Based on the numerical results of this study it can be expected that such a design could decrease the risk of veneering failure in vivo.

Guide surgery osteotomy system (GSOS) a new device for treatment in orthognathic surgery.

INTRODUCTION: This article proposes an innovative and revolutionary diagnostic and therapeutic protocol for performing dentoalveolar osteotomies in office under local anaesthesia with piezoelectric surgery using a surgical acrylic guide produced through software-based planning. METHODS: The method was applied in the correction of crossbites, changing in the curve of Spee, incisal decompensations and dental ankylosis. Performing a preoperative CT with a special splint, optical scanning of the models and the subsequent planning with software has enabled us to produce a model with rapid prototyping with the design of the osteotomy on which the surgical guide was shaped, the use of the guide associated with piezoelectric surgery, allowed to perform surgery under local anaesthesia, with minimal invasiveness and high accuracy. RESULTS: Dentoalveolar immediate movements, with preservation of the roots of teeth involved, allow for rapid treatment of malocclusions which would be long and often difficult if not impossible to treat with orthodontics only. Dentoalveolar osteotomies associated to osteodistraction concepts, allow the orthodontist to achieve with accuracy the objectives required by the treatment plan. CONCLUSIONS: GSOS is a new method, which, utilizing 3D optical scanning images of models, software and piezoelectric surgery, allows to perform dentoalveolar movements which may be dangerous to the roots or for the periodontal support, with orthodontics only. It dramatically reduces total surgical-orthodontic treatment time, with obvious great patient satisfaction.

Analysis of stresses during the polymerization shrinkage of self-curing resin cement in indirect restorations: a finite-element study.

BACKGROUND: Adhesive cementation is essential for the longevity of indirect esthetic restorations. However, polymerization shrinkage of resin cement generates stress, which may cause failures in the tooth-restoration interface. So, understanding of the biomechanics of resin cement is important for predicting the clinical behavior of an esthetic indirect restoration. AIMS: To analyze the stresses generated during polymerization shrinkage of self-curing resin cement in ceramic and in indirect resin (IR) restorations, using the finite-element method (FEM). SETTINGS AND DESIGN: Numerical study using the finite-element analysis. MATERIALS AND METHODS: A three-dimensional (3D) model of a second molar restored with ceramic or IR onlay restoration was designed. The polymerization shrinkage of self-curing resin cement was simulated in FEM software using an analogy between the thermal stress and the resulting contraction of the resin cement. The localization and values of tensile stresses in the dental structure, cement, and adhesive layer were identified. RESULTS: The location and value of the tensile stresses were similar for the two restorative materials. High tensile stresses were identified in the axiopulpal wall and angles of the tooth preparation, with the major stresses found in the cement located in the axiopulpal wall. CONCLUSIONS: The high stresses values and their concentration in the angles of the prepared tooth emphasize the importance of round angles and the use of cements with lower rates of shrinkage.

[Analysis of the plaster casts of Class II division 1 non-extraction patients treated with Alexander technique].

OBJECTIVE: To investigate the changes of arch width and arch length in Class II division 1 non-extraction patients treated with Alexander technique. METHODS: Dental casts of 21 Class II division 1 non-extraction patients treated with Alexander appliance were taken before (T1) and after treatment (T2). All the casts were laser scanned. The arch width and arch length were digitally measured. The differences of arch width and arch length between T1 and T2 were recorded and analyzed. RESULTS: The upper arch length decreased from (32.82 ± 2.51) mm to (31.97 ± 2.17) mm (P < 0.05). The lower arch length increased from (27.53 ± 2.61) mm to (28.80 ± 1.81) mm (P < 0.05). The intercanine width in the upper arch changed significantly from T1 to T2. The intermolar width in the upper and lower arches increased significantly from T1 to T2. CONCLUSIONS: Class II division 1 non-extraction patients could be treated successfully by increasing the upper arch width.

The diagnosis and conservative treatment of a complex type 3 dens invaginatus using cone beam computed tomography (CBCT) and 3D plastic models.

AIM: To investigate the use of 3D plastic models, printed from cone beam computed tomography (CBCT) data, for accurate diagnosis and conservative treatment of a complex case of dens invaginatus. SUMMARY: A chronic apical abscess with a draining sinus tract was diagnosed during the treatment planning stage of orthodontic therapy. Radiographic examination revealed a large radiolucent area associated with an invaginated right maxillary central incisor, which was found to contain a vital pulp. The affected tooth was strategic in the dental arch. Conventional periapical radiographs provided only partial information about the invagination and its relationship with the main root canal and with the periapical tissues. A limited-volume CBCT scan of the maxilla did not show evidence of communication between the infected invagination and the pulp in the main root canal, which could explain the pulp vitality. A novel method was adopted to allow for instrumentation, disinfection and filling of the invagination, without compromising the vitality of the pulp in the complex root canal system. The CBCT data were used to produce precise 3D plastic models of the tooth. These models facilitated the treatment planning process and the trial of treatment approaches. This approach allowed the vitality of the pulp to be maintained in the complex root canal space of the main root canal whilst enabling the healing of the periapical tissues. KEY LEARNING POINTS: Even when extensive periapical pathosis is associated with a tooth with type III dens invaginatus, pulp sensibility tests should be performed. CBCT is a diagnostic tool that may allow for the management of such teeth with complex anatomy. 3D printed plastic models may be a valuable aid in the process of assessing and planning effective treatment modalities and practicing them ex vivo before actually performing the clinical procedure. Unconventional technological approaches may be required for detailed treatment planning of complex cases of dens invaginatus.

Analysis of the plaster casts of Class II division 1 non-extraction patients treated with Alexander technique / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the changes of arch width and arch length in Class II division 1 non-extraction patients treated with Alexander technique.</p><p><b>METHODS</b>Dental casts of 21 Class II division 1 non-extraction patients treated with Alexander appliance were taken before (T1) and after treatment (T2). All the casts were laser scanned. The arch width and arch length were digitally measured. The differences of arch width and arch length between T1 and T2 were recorded and analyzed.</p><p><b>RESULTS</b>The upper arch length decreased from (32.82 ± 2.51) mm to (31.97 ± 2.17) mm (P < 0.05). The lower arch length increased from (27.53 ± 2.61) mm to (28.80 ± 1.81) mm (P < 0.05). The intercanine width in the upper arch changed significantly from T1 to T2. The intermolar width in the upper and lower arches increased significantly from T1 to T2.</p><p><b>CONCLUSIONS</b>Class II division 1 non-extraction patients could be treated successfully by increasing the upper arch width.</p>

Effectiveness of photoactivated disinfection (PAD) to kill enterococcus faecalis in planktonic solution and in an infected tooth model.

OBJECTIVE: The aim of this study was to investigate the effectiveness of photoactivated disinfection (PAD) in killing Enterococcus faecalis (EF) in planktonic solution and in an infected tooth model. METHODS: One hundred and thirty-two glass tubes of EF samples with concentration of 10(14) colony forming units (CFU)/mL and photosensitizer were prepared. Sixteen groups were set up and subjected to diode laser, and then received a radiation energy dose ranging from 0.5 to 5.5 J. The bactericidal effect was measured by the mean CFU of viable EF after irradiation. Sixty single-rooted teeth were selected and contaminated with EF, and then given PAD therapy; 5.25% NaOCl irrigation and saline solution were used to disinfect the root canals. Microbial samples were taken before and after disinfection, and after 72 h recovery, and then the CFU were counted. RESULTS: The bactericidal effect increased linearly with the irradiation energy dose in planktonic solution. For the same irradiation energy dose, the bactericidal effect was greater in group receiving 100 mW than in that receiving 50 mW and exposed to doubled irradiation time (p<0.05). No bacterium was detected after irrigation in the NaOCl group in the root canal model, but the recovery of bacteria after 72 h was detected in 11 samples. Bacteria were detected in all the other groups, and PAD was significantly more effective than saline solution in reducing the number of bacterial cells within the root canals (p<0.05). CONCLUSIONS: PAD was shown to have bactericidal effect on EF, and the bactericidal effect increased linearly with the irradiation energy dose and was superior using higher output power. PAD could decrease EF in root canals effectively, but was no more effective than 5.25% NaOCl, and PAD is more effective in planktonic solution than in root canals.