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Australian Endodontic Journal : the... Aug 2023This study aimed to evaluate the shaping ability of XP-endo Shaper, TruNatomy and EdgeFile X3 during the preparation of resin-printed mandibular molar mesial root...
This study aimed to evaluate the shaping ability of XP-endo Shaper, TruNatomy and EdgeFile X3 during the preparation of resin-printed mandibular molar mesial root canals. Thirty-three resin-based mandibular mesial roots with two canals, obtained from extracted tooth cone-beam computed tomography (CBCT) image and printed on a three-dimensional (3D) printer, were divided into three experimental groups according to the different nickel-titanium (NiTi) systems used for root canal preparation. The specimens were scanned using CBCT imaging before and after root canal preparation. Then images were registered using a dedicated software and changes in the canal area, volume, untouched canal surface and the maximum and minimum dentine wall wear were calculated. The XP-endo Shaper instruments showed improved shaping ability with lower untouched root canal surface and better preservation of root canal anatomy during the preparation of resin-printed mandibular mesial root canals compared with TruNatomy and EdgeFile X3 systems.
Topics: Humans; Female; Nickel; Titanium; X-Ray Microtomography; Root Canal Preparation; Dental Pulp Cavity; Molar; Endometriosis; Equipment Design
PubMed: 35770610
DOI: 10.1111/aej.12649 -
International Orthodontics Jun 2019Interdental stripping is often used in orthodontics to correct discrepancies of tooth shape or size. However, this procedure involves significant risks for the enamel....
INTRODUCTION
Interdental stripping is often used in orthodontics to correct discrepancies of tooth shape or size. However, this procedure involves significant risks for the enamel. The roughness of the enamel surface might depend on the instruments used; it can lead to the accumulation of cariogenic plaque and periodontal problems. The main objective of our study was to evaluate the enamel surface condition after interproximal stripping in the mouth, by comparing different manual and mechanized enamel reduction protocols; on the other hand, the topography of the stripped area was observed to specify its location on the stripped proximal surfaces.
MATERIALS AND METHODS
An in vivo study was carried out: interdental stripping was performed in the mouths of patients undergoing orthodontic treatment and on healthy teeth intended for extraction for orthodontic or periodontal reasons. The sample was divided into four groups: in group 1, the distal faces were stripped with conventional single-sided diamond abrasive strips and non-stripped mesial faces (control faces); in group 2: the distal faces were stripped with the manual ContacEZ IRP Kit (single-sided abrasive files of different grain sizes) and non-stripped mesial faces (control faces); in group 3: the faces were stripped with ContacEZ IRP diamond discs attached to a handpiece and the mesial faces were not stripped (control faces); in group 4: the distal faces were stripped with the Intensiv Ortho-Strips mechanized system and the mesial faces were not stripped (control faces).
RESULTS
Our study showed that regardless of the type of stripping material used, the enamel surface showed some roughness with the presence of striations and grooves of different widths and depths. Our observations objectivised more regular and less roughened enamel surface conditions when using the Intensiv oscillating files. Manual instruments (abrasive strips and files) have shown rougher and more irregular surface conditions that may constitute a real risk of carious and periodontal disease. The macroscopic evaluation of the topography of the stripped area showed that there is great variability in the situation and extent of the stripped area in relation to several parameters.
CONCLUSION
The current mechanized instruments (oscillating files) provide enamel stripping with more comfort for the patient and the practitioner, and seem to produce a more regular and less harmful surface condition for the tooth and periodontium.
Topics: Bicuspid; Dental Enamel; Dental Polishing; Gingiva; Humans; In Vitro Techniques; Microscopy, Electron, Scanning; Surface Properties; Tooth Movement Techniques
PubMed: 30981677
DOI: 10.1016/j.ortho.2019.03.005 -
Beijing Da Xue Xue Bao. Yi Xue Ban =... Feb 2020To evaluate the short-term outcome of regenerative surgery for peri-implantitis therapy.
OBJECTIVE
To evaluate the short-term outcome of regenerative surgery for peri-implantitis therapy.
METHODS
From March 2018 to January 2019, 9 patients with 10 implants who suffered from peri-implantitis were included in the present research. Vertical bone defect at least 3mm in depth with 2 or more residual bone walls was confirmed around each implant by radiographic examination. Restorations were replaced by healing abutments on 3 implants with the consent of the patients. Guided bone regeneration surgery was performed after a hygienic phase. During surgery, full thickness flaps were elevated on both buccal and lingual aspects. Titanium curette was used for inflammatory granulation tissue removal and implant surface cleaning. The implant surface was decontaminated by chemical rinsing with 3% hydrogen peroxide solution. After being thoroughly rinsed with saline, the bone substitutes were placed in bone defects which were covered by collagen membranes. 6 months after non-submerged healing, the clinical parameters including peri-implant probing depth (PD, distance between pocket bottom and peri-implant soft tissue margin) and radiographic bone level (BL, distance form implant shoulder to the first bone-to-implant contact) were used to evaluate the regenerative outcome. PD was measured at six sites (mesial, middle and distal sites at both buccal and lingual aspects) around each implant, and BL was measured at the mesial and distal surfaces of each implant on a periapical radiograph.
RESULTS
The deepest PD and largest BL of each implant ranged from 6-10 mm and 3.2-8.3 mm respectively. All the implants healed uneventfully after surgery. The mean peri-implant PD at baseline and 6 months after surgery were (6.2±1.4) mm and (3.1±0.6) mm respectively, and a mean (3.0±1.5) mm radiographic bone gain was observed, P<0.01. Treatment success was defined as: no sites with residual PD≥6 mm, no bleeding on probing, and BL elevation of at least 1 mm. Nine implants from 8 patients fulfilled the success criteria. Residual pockets with 6 mm in depth and bleeding on probing could be detected in only one implant.
CONCLUSION
Within the limitation of the present research, guided bone regeneration surgery can be used for the treatment of bone defect that resulted from peri-implantitis. Significant PD reduction and radiographic bone gain can be obtained after 6 months observation.
Topics: Alveolar Bone Loss; Bone Substitutes; Collagen; Dental Implants; Humans; Peri-Implantitis; Surgical Flaps; Treatment Outcome
PubMed: 32071464
DOI: 10.19723/j.issn.1671-167X.2020.01.009 -
European Journal of Dentistry May 2021The aim of the present study was to evaluate the surface roughness (SR) of various nickel-titanium (NiTi) rotary endodontic instruments (ProTaper Next [PTN], WaveOne...
OBJECTIVES
The aim of the present study was to evaluate the surface roughness (SR) of various nickel-titanium (NiTi) rotary endodontic instruments (ProTaper Next [PTN], WaveOne Gold [WOG], and ProTaper Gold [PTG]) before and after root canal instrumentation.
MATERIALS AND METHODS
For each type (PTN, WOG, and PTG), the endodontic instrumentation was performed using extracted mandibular molar teeth's curved mesial root canals (curvature: 20-40 degrees) after determining the working length. Each NiTi file was cleaned, and sterilized following preparation of four root canals and characterized for surface properties before and after endodontic instrumentation using a contact-mode three-dimensional surface profiler. The data were analyzed statistically using Statistical Package for the Social Sciences for SR parameters including average surface roughness value (Sa), root mean square roughness (Sq), and peak to valley height (Sz).
RESULTS
Preinstrumentation assessment revealed a significant difference for all the three SR variables < 0.05) for the cutting blade and the flute area. WOG instruments showed the highest SR values ( = 0.000). The postinstrumentation assessment revealed significant differences in SR values in the blade and the flute between the three groups ( < 0.05), with WOG and PTG exhibiting the highest values in the blade and flute sections, respectively.
CONCLUSIONS
The SR parameters of intact PTN, WOG, and PTG NiTi files vary and that was increased following the endodontic instrumentation.
PubMed: 33111285
DOI: 10.1055/s-0040-1718469 -
Journal of Endodontics May 2022This study aimed to evaluate the preservation of periradicular dentin and the enlargement of the apical canal of mandibular molars with TruNatomy (Dentsply Sirona,...
INTRODUCTION
This study aimed to evaluate the preservation of periradicular dentin and the enlargement of the apical canal of mandibular molars with TruNatomy (Dentsply Sirona, Ballaigues, Switzerland) and ProTaper Gold (Dentsply Sirona) instruments.
METHODS
Twenty mandibular molars were scanned in a micro-computed tomographic device, anatomically paired, and distributed into 2 groups (n = 10). In the ProTaper Gold group, mesial and distal canals were prepared up to F2 (25/.08v) and F3 (30/.09v) instruments, whereas in the TruNatomy group, mesial and distal canals were enlarged up to the prime (26/.04v) and medium (36/.03v) instruments, respectively. After a new scan, the surface area, volume, unprepared areas, transportation, percentage of dentin removal, and dentin thickness parameters were calculated. Data were compared between groups using the Mann-Whitney test, the Student t test, and the nonmetric multidimensional scaling test with alpha set at 5%.
RESULTS
No difference was found between groups regarding unprepared canal areas and the reduction of dentin thickness (P > .05). Transportation was lower than 0.1 mm in all groups, and statistical differences were observed only at the apical third of the mesiobuccal canal with lower values in the TruNatomy group. ProTaper Gold removed more dentin than TruNatomy at the coronal level of mesial roots (1.8% and 1.0%, respectively) (P < .05).
CONCLUSIONS
TruNatomy and ProTaper Gold were efficient for performing canal preparation in mandibular molars. The tested systems were similar in terms of untouched canal walls and remaining dentin thickness and slightly different in the apical transportation of mesial canals and the percentage of dentin removal at the coronal third but without clinically significant errors.
Topics: Dental Pulp Cavity; Dentin; Equipment Design; Gold; Humans; Molar; Root Canal Preparation; Titanium; X-Ray Microtomography
PubMed: 35181453
DOI: 10.1016/j.joen.2022.02.003 -
Compendium of Continuing Education in... Mar 2017The purpose of this study was to evaluate if the marginal fit of computer-aided design and computer-aided manufacturing (CAD/CAM) restorations manufactured with CAD/CAM...
OBJECTIVE
The purpose of this study was to evaluate if the marginal fit of computer-aided design and computer-aided manufacturing (CAD/CAM) restorations manufactured with CAD/CAM systems can be affected by different tooth preparation designs.
METHODS
Twenty-six typodont (plastic) teeth were divided into two groups (n = 13) according to the occlusal curvature of the tooth preparation. These were the group 1 (control group) (flat occlusal design) and group 2 (curved occlusal design). Scanning of the preparations was performed, and crowns were milled using ceramic blocks. Blocks were cemented using epoxy glue on the pulpal floor only, and finger pressure was applied for 1 minute. On completion of the cementation step, poor fits between the restoration and abutment were measured by microphotography and the silicone replica technique using light-body silicon material on mesial, distal, buccal, and lingual surfaces.
RESULTS
Two-way ANOVA analysis did not reveal a statistical difference between flat (83.61 ± 50.72) and curved (79.04 ± 30.97) preparation designs. Buccal, mesial, lingual, and distal sites on the curved design preparation showed less of a gap when compared with flat design. No difference was found on flat preparations among mesial, buccal, and distal sites (P < .05). The lingual aspect had no difference from the distal side but showed a statistically significant difference from mesial and buccal (P < .05).
CONCLUSIONS
Difference in occlusal design did not significantly impact the marginal fit. Marginal fit was significantly affected by the location of the margin; lingual and distal locations exhibited greater margin gap values compared with buccal and mesial sites regardless of the preparation design.
Topics: Cementation; Ceramics; Computer-Aided Design; Crowns; Dental Marginal Adaptation; Dental Prosthesis Design; Humans; Tooth Preparation, Prosthodontic
PubMed: 28257220
DOI: No ID Found -
Journal of Dental Sciences Apr 2022As the number of patients with osteoporosis requiring orthodontic treatment is increasing with the aging of society, it is necessary to evaluate the relations between...
BACKGROUND/PURPOSE
As the number of patients with osteoporosis requiring orthodontic treatment is increasing with the aging of society, it is necessary to evaluate the relations between bone metabolism in old age and orthodontic tooth movement (OTM). However, the effects of changes in bone metabolism due to osteoporosis on OTM and root resorption are still unclear. Therefore, we investigated the effects of OTM and root resorption in a mouse ovariectomy (OVX)-induced osteoporosis model.
MATERIALS AND METHODS
Eight-week-old female wild-type mice underwent OVX or sham surgery (Sham) as controls. One month after treatment, a nickel titanium coil spring was used to apply a mesial force to the maxillary left first molars of OVX or Sham mice for 12 days. The distance between the maxillary first molar and the second molar changed due to OTM and osteoclast formation was evaluated. The odontoclast formation and root resorption along the root surface of the distobuccal root of the first molar was also evaluated by histological analysis and scanning electron microscopy.
RESULTS
Distance of tooth movement and osteoclast formation were significantly increased in OVX mice compared to Sham controls. Furthermore, root resorption in the mesial surface of the distal molars induced by orthodontic force was significantly increased in OVX mice.
CONCLUSION
The amount of OTM was significantly increased, and the accompanying root resorption was also increased in OVX mice. Therefore, attention should be paid to the risk of root resorption associated with orthodontic treatment in patients with osteoporosis.
PubMed: 35756770
DOI: 10.1016/j.jds.2021.11.009 -
Cureus Jul 2022External cervical resorption (ECR) is a dynamic pathological process characterized by its cervical position on the root and arises below the epithelial attachment and...
External cervical resorption (ECR) is a dynamic pathological process characterized by its cervical position on the root and arises below the epithelial attachment and the coronal part of the bone. This report will highlight a case of ECR in an asymptomatic patient. A radiolucent area was noted during a routine dental follow-up examination on the bitewings at the mesial surface of the upper right second premolar. Persistently, the radiolucency had multiple radiographic views indicating a true form of a lesion that could be diagnosed as external cervical resorption. The patient did not report any complaints since dental treatment was completed in 2016. After a series of radiographs and conducting further diagnostic measures, a diagnosis of ECR was confirmed. The best treatment of choice for this case was extraction and restoring the missing tooth with an implant-supported crown. The size and the extent of such a defect could affect the strategy for implant placement. This paper aimed to report that ECR can be asymptomatic for a long time with advanced cervical root resorption in some cases.
PubMed: 36043004
DOI: 10.7759/cureus.27334 -
Journal of Dentistry Jun 2020The fracture strengths of four types of occlusal veneers and a traditional full crown ceramic restoration and the influence of preparation design on the stress of...
OBJECTIVES
The fracture strengths of four types of occlusal veneers and a traditional full crown ceramic restoration and the influence of preparation design on the stress of restorations were examined.
METHODS
Forty intact maxillary premolars randomly divided into five groups were prepared based on the demands of type O (occlusal surface coverage), OF (occlusal and lingual surface coverage), POF (occlusal, lingual, and mesial surface coverage), and POFP (occlusal, lingual, mesial, and distal surface coverage) veneers and full crown, and then restored by glass ceramic. Specimens were subjected to fracture resistance tests after cyclic loading. The fracture strengths and modes were analyzed statistically. The level of significance was set at α = 0.05. One maxillary premolar was prepared for type O, OF, POF, POFP veneer and full crown, and then scanned to establish finite element models. The mean fracture load was applied vertically to calculate the maximum principal stress on the ceramic.
RESULTS
Type O veneer showed higher fracture strength than type POF and POFP veneers (P < 0.05). Both type O and OF veneers exhibited higher fracture strength than full crown (P < 0.05). No significant difference in failure mode was observed. The maximum principal stress for type O, OF, POF, POFP veneers, and full crown increased progressively and concentrated at the bonding surface directly beneath the loading area.
CONCLUSIONS
Four types of occlusal veneer showed fracture strengths that considerably exceeded normal biting forces. They represent conservative alternatives to full crowns and present a viable treatment for severely worn teeth.
CLINICAL SIGNIFICANCE
The occlusal veneers with different preparation designs, including type O, OF, POF and POFP veneers, show higher fracture resistances than traditional full coverage crowns that considerably exceed the normal biting forces. Therefore, these represent conservative alternatives to crown restorations and present a viable treatment for restoring severely worn teeth.
Topics: Bicuspid; Ceramics; Crowns; Dental Porcelain; Dental Stress Analysis; Dental Veneers; Materials Testing
PubMed: 32325176
DOI: 10.1016/j.jdent.2020.103346 -
Journal of International Society of... 2021The aim of this investigation was to detect defects that may occur to Reciproc endodontic files after a single use.
OBJECTIVE
The aim of this investigation was to detect defects that may occur to Reciproc endodontic files after a single use.
MATERIALS AND METHODS
A sample of convenience of Reciproc files (VDW GmbH, Munich, Germany) that were used to prepare root canals of anterior or posterior teeth were collected. The files were divided equally into two groups: Group 1 (R25) files were used to prepare mesial root canals of 50 human permanent mandibular molars, and Group 2 (R40) included 50 files that were used to prepare permanent maxillary incisor teeth. Files were analyzed after single use by using a scanning electron microscope at X120 to detect changes in surface morphology. The data were statistically analyzed by using the χ test, and statistical significance was set at < 0.05.
RESULTS
A total of 96 Reciproc NiTi files were collected; of those, 67 (70%) were unaffected and 29 (30%) showed overall surface deformations. The types of deformation were blade disruption (22%), surface pitting (12%), and unwinding and tip deformation (1%). No microcracks were detected, and none of the studied files showed fracture. R40 was three times more likely to be deformed and showed blade disruption compared with R25 ( < 0.05).
CONCLUSIONS
Reciproc rotary NiTi files show high resistance to deformation after a single use. Blade disruption was the most frequent defect occurring in both the small and large files.
PubMed: 33688479
DOI: 10.4103/jispcd.JISPCD_412_20