Dental Journal

Impact of chitosan modification on the material properties of acrylic resin base

2024-04-19T07:45:42+07:00

Background: 3D-printed polymethyl methacrylate is a light-cured commercial resin used in the 3D printing sector due to its affordability, good adaptability, minimal odor, and low irritation. Purpose: To investigate the impact of modified chitosan on the surface hardness and flexural strength of printed dental resin. Methods: A modified chitosan solution was cross-linked with adipic acid at concentrations of 0.1, 0.05, and 0.01 wt.% and then added to 3D-printable acrylic resin at 2, 5, and 10 wt.%. After addition, samples were prepared to test surface hardness and flexural strength. A total of 100 specimens were used in the research, grouped into 10 sets. Five specimens were prepared for each additive percentage, and five specimens served as a control group (3D-printable resin without modification) for each test. Results: The results showed that the (adipic acid/chitosan) 0.1/2 wt.% group had the highest flexural strength (134.370 MPa) and surface hardness (32.46 VHN), while the lowest flexural strength (49.198 MPa) and surface hardness (21.22 VHN) were observed in the (adipic acid/chitosan) 0.01/10 wt.% group. Conclusion: Modification of chitosan with adipic acid positively influences the flexural strength and surface hardness of 3D-printed denture bases. However, increasing the chitosan content beyond 2 wt.% reduces both surface hardness and flexural strength in modified 3D-printed polymers.

Cone beam computed tomography in detecting the second mesiobuccal canal in the upper molars: A pilot study

2024-05-21T08:21:23+07:00

Background: Root canal treatment aims to heal and/or prevent apical periodontitis. It is accomplished by removing inflamed or necrotic pulp, followed by sealing with the appropriate materials. Studies show that the endodontic treatment of the maxillary molars has the highest failure rate because of anatomical variations in the mesiobuccal (MB) roots. Purpose: This study aims to evaluate cone beam computed tomography (CBCT) to accurately identify the second mesiobuccal (MBII) canal in human maxillary first molars. Methods: The investigation was approved by the Research Ethics Committee of the Research Management Institute, Universiti Teknologi MARA (UiTM). Images were sourced from the Radiology Unit of the Centre for Oral Radiology Studies, Faculty of Dentistry, UiTM. CBCT images of permanent maxillary molars (n = 24) were selected. The images were of intact permanent maxillary first molars with complete root formation, with or without the presence of obturation material. The presence or absence of the MBII canals was analyzed by three examiners, and the data were recorded. Results: The MBII canals were present in 86% (n = 19) of the investigated upper first molars. All of the previously endodontically treated teeth (n = 10) revealed the presence of MBII canals, which were not obturated. Seventy-five percent (n = 3) of the patients exhibited four canals in both the right and left upper first molars. Conclusion: The MB roots of maxillary molar teeth have more variations in their canal system than the other two roots. CBCT is a good diagnostic tool for detecting and mapping the MB root-canal system and can potentially improve the quality of endodontic treatment.

In vitro evaluation of the effectiveness of pediatric drugs and tooth brushing on the surface roughness of different restorative dental materials used in pedodontics

2024-04-23T15:28:18+07:00

Background: Liquid oral drugs are frequently used in children. Knowing the effects of these drugs and individual oral hygiene brushing on the surface roughness (SR) of dental restorative materials with different contents used in pediatric dentistry is clinically important. Purpose: The aim is to assess the effects of various drugs and toothbrushes used in children on the SR of dental restorative materials. Methods: A total of 60 samples of different dental filling materials (polyacid-modified composite resin [compomer], glass ionomer cement [GIC], and composite resin) were prepared. The specimens were divided into six solution groups (distilled water, antibiotics, analgesics, antiepileptics, bronchodilators, and anti-allergic drugs). For each group (n = 5), two subgroups (brushing and non-brushing) were created. Surface roughness values (Ra) were measured at baseline and at the first and fourth weeks using a profilometer. The data were analyzed using analysis of variance, post-hoc analysis, and the Bonferroni test (p < 0.05). Results: The highest roughness value among all drug groups was detected in the non-resin-containing traditional GIC material. In addition, the brushing condition had a statistically significant effect on SR values (p < 0.05). The smallest change in roughness from baseline to the fourth week was observed in the non-brushed composite material in the Amoklavin group, whereas the largest change was observed in the brushed GIC material in the Depakin solution. Conclusion: Drug solutions and brushing affect the SR of restorative materials, with resin-containing materials being less affected than GIC.

Bacterial profile and antibiotic sensitivity in silk sutures following odontectomy

2024-04-23T14:55:19+07:00

Background: Impacted teeth, hindered from erupting normally due to space constraints, obstruction by neighboring teeth, or an abnormal eruption pathway, often necessitate surgical intervention known as odontectomy. Silk sutures are commonly used in this procedure, yet they may serve as sites for bacterial colonization, potentially leading to infection. Following odontectomy, antibiotics are typically prescribed. Purpose: This study aims to identify the bacterial profile adhering to silk sutures and analyze antibiotic sensitivity patterns in patients undergoing odontectomy. Methods: A descriptive study employing consecutive sampling of patients after odontectomy was conducted between May and November 2021 at Arifin Achmad General Hospital, Riau Province, Indonesia. Sutures were removed within 14 days of surgery, after which the silk was identified and subjected to antibiotic sensitivity testing using the Kirby–Bauer method. Results: Of the bacteria detected in the silk sutures, 53.7% were Gram positive, including Streptococcus sp. (33.3%) and Staphylococcus aureus (13%), and 46.3% were Gram negative, such as Enterobacter sp. (20.4%) and Klebsiella sp. (16.7%). Among the multi-resistant strains, methicillin-resistant S. aureus (MRSA) accounted for 57.1%. The Gram-positive bacteria exhibited the highest sensitivity to levofloxacin, whereas the Gram-negative bacteria showed sensitivity to ceftazidime, levofloxacin, and meropenem. Conclusion: The most dominant Gram-positive bacteria were Streptococcus sp. and S. aureus, whereas the most dominant Gram-negative bacteria were Enterobacter sp. and Klebsiella sp. Levofloxacin, ceftazidime, and meropenem emerged as the most effective antibiotics following odontectomy. Multidrug-resistant bacteria, exemplified by MRSA, were identified within the oral cavity.

Characteristics of chitosan from Penaeus monodon on chitosan-gelatin suspension viscosity

2024-08-22T09:51:15+07:00

Background: Chitosan synthesized from Penaeus monodon shells was developed into a chitosan-gelatin suspension as an injectable bone substitute for socket preservation. Purpose: To investigate the characteristics of chitosan from P. monodon shells and their influence on the viscosity of a chitosan-gelatin suspension. Methods: P. monodon shells from Tarakan Waters were prepared using three methods: Group 1) deproteinization-depigmentation-deacetylation, Group 2) demineralization-depigmentation-deacetylation, and Group 3) deproteinization-demineralization-depigmentation-deacetylation. The chitosan was characterized by morphology, moisture and ash content, molecular weight (MW), deacetylation degree (DD), and viscosity. This chitosan was made into a chitosan-gelatin suspension with a ratio of 45:55 (w/w%) (95 ml:110 ml). The differences in viscosity of the chitosan-gelatin suspension were determined using Kruskal–Wallis and Mann–Whitney tests. The effects of the chitosan’s MW and DD on the viscosity of the chitosan-gelatin suspension were analyzed using Spearman’s correlation. Results: Group 2 had the highest moisture content (10.63%), MW (159.68 kDa), viscosity of the chitosan powder (5.53 dPa.s), and viscosity of the chitosan-gelatin suspension (40.20 cps). Group 1 had the highest ash content (27.83%) and DD (93.72%). Group 3 showed the lowest ash content (1.06%), MW (37.12 kDa), and DD (86.22%), but it had good viscosity of the chitosan-gelatin suspension (37.25 cps). A significant difference in viscosity was found between the chitosan-gelatin suspension groups. Spearman’s correlation coefficients between the viscosity of the chitosan-gelatin suspension and MW and between the viscosity of the chitosan-gelatin suspension and DD were 0.389 and −0.195, respectively. Conclusion: The viscosity of a chitosan-gelatin suspension is influenced by the MW and DD of the chitosan powder. Chitosan from P. monodon can potentially be an injectable bone substitute in socket preservation.

Immuno-expression analysis of VEGF and CD34 related to histological types of mandibular ameloblastoma

2024-04-29T08:01:17+07:00

Background: Increased expression of vascular endothelial growth factor (VEGF) and cluster of difference 34 (CD34) in ameloblastoma has been noted. Both proteins are markers of angiogenesis that play a role in supporting the growth of ameloblastoma. The existence of histopathological types of ameloblastoma allows for differences in behavioral and growth characteristics. Purpose: To evaluate the differences and correlation of VEGF and CD34 expression in histological types of ameloblastoma. Methods: This laboratory cross-sectional study uses total sampling from histological slides of mandibular ameloblastoma. Two observers manually quantified the immunohistochemical expression. The comparative data were analyzed statistically with the Kruskal–Wallis test (p < 0.05), while the correlative data were analyzed with Spearman’s rho (p<0.01). Results: 32 samples were obtained according to the inclusion criteria. The Kruskal–Wallis test showed significant differences in VEGF expression (p = 0.003) and CD34 expression (p = 0.026). The pairwise comparison test showed that VEGF expression in follicular ameloblastoma significantly differed from plexiform (p = 0.001) and combination (p = 0.002). The pairwise comparison test for CD34 expression showed a significant difference between follicular and combination ameloblastoma (p = 0.007). Spearman’s rho test showed a positive correlation (p = 0.001, r = 0.565) between markers. Conclusion: Follicular ameloblastoma expressed higher VEGF than plexiform and combination ameloblastoma. Follicular ameloblastoma expressed higher CD34 than combination types. CD34 expression is associated with VEGF in histological types of ameloblastoma.

The influence of the polishing duration on the surface roughness and gloss of nanohybrid composites using a blood cockle shell polishing paste

2024-05-28T10:07:04+07:00

Background: The polishing procedure is an important stage in producing a successful restoration. Polishing involves the use of abrasive materials, and blood cockle shells contain these natural components, such as calcium carbonate, which can be used as a polishing paste. One of the factors that influences the polishing quality is the polishing duration. Purpose: This study evaluated the polishability of a nanohybrid composite using blood cockle shell polishing paste by measuring the surface roughness and gloss value, and by observing the surface qualities based on different polishing times. Methods: Ninety samples of maxillary premolars were immersed in artificial saliva in an incubator at 37°C for 24 h. A total of 45 samples were subjected to a profilometer to observe surface roughness, and the rest were subjected to a glossmeter to observe the composite resin gloss. These included blood cockle shell paste, Prisma Gloss polishing paste, and without paste for 30, 60, and 90 seconds. The data were statistically analyzed using repeated measures ANOVA and post hoc least significant difference (LSD). Results: It showed that the group of 90 seconds had the highest gloss and the lowest surface roughness in the blood cockle shells. The difference was statistically significant (p>0.05). The results of the surface roughness test of the blood cockle shells with a duration of 30 and 60 seconds were found to be not significant (p<0.05). Conclusion: There were significant differences by adding the polishing duration, which decreased the surface roughness and increased the surface gloss, in which the lowest roughness and highest glossiness was found with a polishing time of 90 seconds. The polishability of composite resin restorations in this study obtained the best gloss and smoothest surface results from the longest polishing time duration of 90 seconds with the blood cockle shell polishing paste.

The effect of Novamin on enamel content after bracket removal

2024-05-06T09:06:41+07:00

Background: Orthodontics is one of the dental rehabilitation treatments for malocclusion correction, such as fixed orthodontic treatment using brackets, as the use of orthodontic brackets for a prolonged period can damage the enamel. Novamin contains casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), which can be used to prevent enamel erosion. Purpose: The aim of this study is to elucidate the effect of Novamin on the enamel content and microstructure surface after bracket removal. Methods: This study used 25 human premolar teeth randomly divided into five groups: I (Control); II (Biofix etching and bracket mounting); III (Biofix-Novamin); IV (Fuji Ortho); and V (Fuji Ortho-Novamin). Results: The results represent significant differences in the average levels of calcium (Ca) and phosphorus (P) among the treatment groups (p ≤ 0.05). The changes to the enamel surface indicated the opening of enamel prisms, pits, and grooves. The levels of Ca and P increased after applying Novamin, especially in groups II and III, indicating remineralization on the enamel surface. When Novamin reacts with saliva, it starts to remineralize, and sodium ions are released. The sodium ions exchange with hydrogen cations, releasing Ca and P ions from Novamin particles. Conclusion: Novamin presented the capability to stimulate remineralization after orthodontic bracket debonding through altering the Ca and P levels on the enamel surface.