Evaluation of scanning accuracy for two commercially available intraoral scanners in reproducing orthodontic bracket dimensions

OBJECTIVE

The aim of this study was to compare the scanning accuracy of two different intra-oral scanners- MEDIT i500 and TRIOS 3 shape in reproducing orthodontic bracket dimensions.

MATERIALS AND METHODS

This in vivo cross-sectional study comprised seven subjects with a full complement of permanent dentition without third molars. Complete arch scanning was carried out with two intraoral scanners, such as MEDIT i500, TRIOS 3 shape, after bonding with brackets. The control group consisted of bracket dimensions measured directly by using Vernier calipers before bonding. Bracket dimensions of three-dimensional (3D) images were measured by using OrthoAnalyzer software. The accuracy of intraoral scanning was investigated by comparing bracket dimensions among the three groups using One-way ANOVA and Post-Hoc Tukey HSD test, and by evaluating outcomes for each quadrant and an individual tooth in complete-arch scans.

RESULTS

When comparing bracket dimensions of 3D images with manual measurements using a traditional Vernier caliper, MEDIT i500 showed no significant difference when compared to the control group (p>0.05) in full arch scanning as well as the quadrant and single tooth scans in complete arch scanning. TRIOS 3 shape showed a significant difference when compared to the control and MEDIT i500 group (p<0.05) for all parameters.

CONCLUSIONS

MEDIT i500 showed higher accuracy and better reproduction of orthodontic bracket dimensions than TRIOS 3 shape.

Comparison of bacterial colonization on absorbable non-coated suture with Triclosan- or Chlorhexidine-coated sutures: a randomized controlled study

OBJECTIVE

The oral cavity is a colossal reservoir for the bacteria. The healing of tissues is compromised after flap surgery, particularly in the presence of sutures, as they can act as repositories for bacteria, ultimately leading to surgical site infections. Hence, antibacterial-coated sutures have been considered as an alternative to reduce the risk of these infections and further improve the wound healing of the tissues after flap surgery. Since minimal information is available on the effect of antibacterial-coated sutures on periodontal tissues, this study aims to clinically and microbiologically assess the antibacterial efficacy of Triclosan (TCS) and Chlorhexidine-coated sutures (CCS) on periodontal tissues compared to non-coated sutures (NCS).

PATIENTS AND METHODS

A total of 75 subjects with moderate to severe periodontitis were included in the study and randomly allocated to one of the three groups, (TCS, CCS, and NCS groups) equally. Suture removal was performed on postoperative day 8, and parameters such as wound healing and post-operative pain were evaluated. The retrieved suture samples were subjected to microbiological analysis and the bacteria were identified quantitatively and qualitatively.

RESULTS

Intragroup analysis of the wound healing index and post-operative pain for all the groups showed a significant improvement (p<0.01), from day 8 to day 30. Intergroup analysis of the wound healing index revealed significant wound healing (p<0.05) on day 15 and day 30. For post-operative pain, intergroup analyses showed significantly low pain scores (p<0.01) for the TCS group. Microbiologic analysis of aerobic colony counts in both anterior and posterior regions revealed significantly (p<0.01) least colony counts in TCS and highest colony counts in NCS groups, respectively. Although anaerobic colony counts were not statistically significant, relatively fewer colony counts were identified in the TCS group. Whereas, relatively higher anaerobic colony counts were seen in the CCS group in the anterior region and in the NCS group in the posterior region. Qualitative assessment revealed higher amounts of Streptococcus and Staphylococcus species in all the three groups (TCS, CCS, and NCS groups).

CONCLUSIONS

Antibacterial-coated sutures, particularly Triclosan-coated sutures, are effective in reducing bacterial accumulation compared to non-coated sutures. Therefore, these sutures can be effectively utilized in periodontal flap surgery.

In Vitro Evaluation of marginal adaptation of polyether ether ketone and zirconia copings

Background

Polyether ether ketone (PEEK) has emerged as a new thermoplastic material with potential applications as a restorative material. Aim: This study aimed to evaluate the marginal adaptation of PEEK copings compared to zirconia copings using field emission scanning electron microscopy.

Materials and Methods

A freshly extracted maxillary central incisor was prepared for a full-coverage restoration following standard principles of tooth preparation. The tooth was sent to a laboratory for fabrication of samples using computer-aided design and manufacturing (CAD/CAM). Twenty samples of polyether ether ketone (PEEK) copings (group A) and 20 of zirconia copings were fabricated (group B). The copings were scanned under a field emission scanning electron microscope and measurements were taken at four distinct points. The marginal adaptation over the buccal, lingual, mesial, and distal margins for both groups was evaluated. One-way analysis of variance (ANOVA) and independent t test were applied.

Results

Our findings indicate that PEEK showed better marginal adaptation than zirconia at all measurement points. The mean marginal gap value of the PEEK group was 33.99 ± 8.81 μm and of the zirconia group was 56.21 ± 15.07 μm. On comparing marginal adaptation among the mesial, distal, buccal, and lingual aspects, PEEK showed better adaptation on all four margins, with the best adaptation on the buccal margin that had the lowest mean gap value of 29.27 ± 6.07 μm. The zirconia group adapted best at the distal margin, with a lowest mean gap value of 53.58 ± 15.25 μm (P ≤ 0.05).

Conclusion

PEEK copings had better marginal adaptation and fit compared to zirconia copings. It may have applications as a restorative material in fixed prostheses.

Root surface changes following manual and ultrasonic instrumentation - a scanning electron microscopic study

OBJECTIVE

The aim of this study is to assess the efficacy of hand and ultrasonic scaling and to evaluate the surface roughness on the root surface of periodontally involved teeth using a scanning electron microscope.

PATIENTS AND METHODS

A sample of 90 single-rooted teeth with a hopeless prognosis was selected for the study and divided into three separate groups. Group I consist of no treatment. In Group II, hand scaling was done using Gracey curettes, and in Group III, ultrasonic scaling was done. The teeth were then extracted and fixed in 10% formaldehyde solution for 24-48 hours and subjected to scanning electron microscopic (SEM) evaluation.

RESULTS

The SEM analysis revealed that the remaining calculus index was found to be similar in the ultrasonic group and the hand scaling group, whereas the surface roughness was found to be the least in the ultrasonic group.

CONCLUSIONS

Hand instrumentation has resulted in more surface roughness as compared to ultrasonic instruments.

A split-mouth randomized controlled trial to compare the rate of canine retraction after a soft tissue procedure compared against a corticotomy procedure for accelerated tooth movement

Background and Aim

Various methods to accelerate the orthodontic tooth movement have been used, among which corticotomy is considered to be the most common one. The suggested reasoning for such acceleration was the regional acceleratory phenomenon (RAP). Since the RAP is a property of both the hard and soft tissues, we designed a soft tissue flap procedure to compare the effects with the conventional corticotomy procedure. A split-mouth study was conducted where the two procedures were assessed in a single participant.

Patients and Methods

The total sample size was calculated to be 40 with 20 participants in each group. The rate of tooth movement was the primary outcome measure, and the secondary outcomes were dentoalveolar changes, which were studied in both the conventional corticotomy and the flap-only procedure based on a cone-beam computed tomography (CBCT) wherein the alveolar bone density (BD) around canines, tipping, and rotational changes in canines, premolars, and molars were assessed.

Results

Corticotomy resulted in greater canine angulation, lesser canine rotation and premolar rotation, and greater molar rotation compared with flap elevation, but these differences were statistically insignificant.

Conclusion

Though the corticotomy resulted in higher BD, the differences were statistically insignificant. There was no significant difference in the rate of space closure assessed by the two techniques compared.

Antimicrobial Efficacy of Blended Essential Oil and Chlorhexidine against Periodontal Pathogen (P.gingivalis)-An In Vitro Study

Background

Essential oils (EOs) have a considerable amount of therapeutic and preventive effect in treating dental diseases due to their wider potential as antibacterial and anti-inflammatory agents. EOs like virgin coconut oil, eucalyptus oil, peppermint oil thyme oil, and clove oil, when used in combination, may further have enhanced antimicrobial effects. However, limited information exists on the synergistic effect of these oils when used in combination, especially on the primary periodontal pathogen Porphyromonas gingivalis.

Aim

The current study aims to compare the antimicrobial efficacy of commercially available EO on the periodontal pathogen, P. gingivalis, in comparison to chlorhexidine (CHX).

Materials and Methods

Antimicrobial efficacy of EO and CHX was assessed at various concentrations against the periodontal pathogen P. gingivalis, by evaluating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).

Results

P. gingivalis was seen to be sensitive at a MIC of 100 μg/ml and 50 μg/ml concentration of the EO, which is regarded as the MIC of EO against P. gingivalis and CHX effectively inhibited microbial growth at 0.4 μg/ml.

Conclusion

A combination of EOs possesses a potent antibacterial activity against P. gingivalis, and the antibacterial efficacy increases with increasing concentration of EOs.

Anti-microbial efficacy of root canal preparation in deciduous teeth with manual and rotary files: A randomized clinical trial

BACKGROUND

In a pulpectomy, the eradication of microbes from the primary root canal is accomplished through biomechanical preparation, which could be carried out with either manual or rotary instruments.

AIMS

The objective of this clinical trial was to evaluate the efficiency of manual K-files, H-files, and Kedo-S Square rotary files in reducing microbial flora after canal preparation in primary molars.

MATERIALS AND METHODS

This randomized clinical trial consisted of 45 primary molars requiring pulpectomy. The teeth were randomly allocated to one of the three groups: Group I: Manual K-files, Group II: Manual H-files, and Group III: Kedo-S Square rotary files, based on the type of instrumentation. Pre-and Post-instrumentation sampling was performed using clean absorbent paper points and kept in a clean Eppendorf tube having thioglycolate broth as the transport medium. Culturing was performed on agar media from which both aerobic and anaerobic microbial counts were estimated. Collected data were statistically analyzed using one-way analysis of variance (ANOVA) and Wilcoxon signed-rank test. Following root canal preparation, 87-89% reduction of the aerobic and anaerobic microbial load was noted in group I, whereas it was an 89-92% reduction in group II and a 93-95% reduction in group III.

RESULTS

Biomechanical preparation with Kedo-S Square rotary file showed higher efficacy in microbial reduction compared to manual instrumentation.

CONCLUSION

Manual and rotary files were equally effective in removing root canal microbes. Biomechanical preparation with a KedoS Square rotary file resulted in greater microbial efficacy. Hence In children, effective root canal cleaning in a short period of time is a major consideration.

Comparison of biochemical markers of bone metabolism between conventional labial and lingual fixed orthodontic appliances

Objectives

The applied orthodontic force causes remodeling of the periodontium through the selective release of cytokines causing resorption of bone, enabling controlled movement of the tooth. This study compared the cytokine profile between patients treated with conventional labial and lingual fixed orthodontic appliances.

Patients and Methods

The study included 80 patients in need of orthodontic treatment, out of which 40 patients were treated by the labial fixed appliance and 40 by the lingual fixed appliance. Gingival crevicular fluid (GCF) specimens were gathered from both the groups using a microcapillary pipette. The samples were collected at the beginning of the treatment and after 21 days. Enzyme-linked immunosorbent assay was performed to evaluate the cytokine levels.

Results

Interleukin (IL)-1α, 1β, 2, 8, and tumor necrosis factor-alpha (TNF-α) levels were significantly high (P < 0.001) in GCF of participants treated with conventional labial fixed appliance. IL-1α, 1β, 2, 6, 8, and TNF-α levels were significantly high (P < 0.001) in GCF of participants treated by the lingual fixed appliance. The concentrations of TNF-α and IL-1β were increased higher than other cytokines in both the treatment groups.

Conclusion

Overall, the lingual fixed appliance had higher cytokine levels than a labial fixed appliance. Analyzing the GCF cytokine levels during orthodontic treatment could provide an ideal platform for monitoring the progress of the treatment.

Uptake and release of fluoride from fluoride-impregnated chewing sticks (miswaks) in vitro and in vivo

The purpose was to investigate the uptake and release of fluoride (F) from F-impregnated chewing sticks (miswaks). In the first series, 3-cm-long pieces were impregnated in 1, 2, 3 and 4% NaF solutions for 3 h, 1 day and 3 days (10 pieces/test). There was a dose-response effect with respect to both impregnation time and the concentration of the F solution. In the second and third series, totally 40 miswak pieces were impregnated in 3% NaF for 1 day and 3 days; the outer layer (bark) was separated from the inner spongy part (pulp) and analyzed separately. F was released from both parts, but somewhat more was released from the bark than from the pulp; a plateau was reached at around 30 min. In vivo, 9 healthy subjects used three products for 2 min in a crossover design: (1) a miswak impregnated in 3% NaF for 1 day, (2) a miswak impregnated in 3% NaF for 3 days, and (3) 1 g of F toothpaste (containing 1,450 ppm F as NaF) on a toothbrush. The highest F concentration at the approximal area was obtained after using the miswak impregnated in 3% NaF for 3 days compared with the other products (p < 0.05 or p < 0.01). To conclude, NaF-impregnated miswaks produced a rapid release of F in vitro as well as in vivo and may be an interesting vehicle for home care use for caries prevention in countries where they are used regularly.