Khon Kaen University Dental Journal

The Effect of COVID-19 Pandemic Among Dental Students, Naresuan University

2023-09-22T11:41:09+07:00

This qualitative study aimed to evaluate the effect of the COVID-19 pandemic among undergraduate dental students at Naresuan University, Thailand. Semi-structured interviews and focus group discussions were conducted between August 2021 to April 2022. A total of 48 dental students (Year 1-6 of the academic year 2021) were included in the study. The study showed that the COVID-19 pandemic affected dental students in five aspects: education, health, economic, social, and others. Firstly, for the educational aspect, changing types of teaching from onsite to online classes allowed students more flexibility and convenience. However, some subjects were difficult to understand from online learning. In addition, the students could be easily distracted by unstable devices and internet connection. The exam was much harder and there were a lot more assignments. Furthermore, a decrease in the number of patients during COVID-19 affected with the students’ clinical practice requirements. Secondly, the spread of the COVID-19 affected the students’ health, both physically and mentally, such as stress, anxiety, and the risk of getting infected by the disease. For the economic aspect, many students' families had lower incomes while there were increasing expenses for both daily use and education. In term of the social aspect, most of the students were challenged by the change in social interactions, connections, and travel restrictions caused by preventive measures. However, this situation created opportunities for students to do other activities to increase their skills and income during their free time.

A Study of The Relationship of Maxilla and Mandible in Unilateral and Bilateral Cleft Lip and Cleft Palate Patients Undergoing Alveolar Cleft Bone Graft Surgery: A Retrospective Study

2023-10-12T09:50:22+07:00

The aims of this study were to study the relationship of maxilla and mandible in unilateral cleft lip and cleft palate (UCLCP) and bilateral cleft lip and cleft palate (BCLCP) patients undergoing secondary alveolar bone graft (SABG) and to study the effect of SABG on the growth of maxilla and mandible. This retrospective study was collected data in cleft lip and palate patients who had SABG at Oral and Maxillofacial surgery clinic, Faculty of Dentistry, Khon Kaen University from January 2010 to December 2020. The study was performed by digital measuring the angles and distances from the cephalometric radiographs. The parameters represented the horizontal and vertical relationship and the growth of maxilla and mandible. A total of 21 patients with 18 UCLCP and 3 BCLCP were included in this study. In UCLCP group, we used the marginal homogeneity test to analyze the relationship of maxilla and mandible and Paired T-Test to analyze the growth of maxilla and mandible after SABG. We found that the relationship of maxilla and mandible were not significantly change (p=0.317), and found continual growth of both jaws. In BCLCP group, we used descriptive statistic to explain the change of the relationship of maxilla and mandible and the growth of both jaws. We found that the vertical relationship has change after SABG, by the way maxilla and mandible are still continue to grow. It is concluded that after SABG, the relationship of the maxilla and mandible in UCLCP was not significantly change and the vertical relationship of maxilla and mandible in BCLCP has change. Moreover, the maxilla and mandible still have continual growth in both groups.

Prediction of the Pharyngeal Airway Space Change after Bilateral Sagittal Split Ramus Osteotomy (BSSRO) Setback in Patients with Skeletal Class III Deformity

2023-11-13T16:56:07+07:00

The patients with skeletal class III deformity who underwent bilateral sagittal split ramus osteotomy (BSSRO) setback procedure may have the changes of the pharyngeal airway space (PAS). The purposes of the study were to determine the factors and create regression equations to predict PAS changes using these factors. This was a retrospective analytical cross-sectional study. Lateral cephalometric radiographs were analyzed from 40 patients before surgery (T0, within 3 months pre-operation) and > 6 months after surgery (T2, long-term follow-up). The PAS changes at level of retropalatal airway space (PAS-p) showed the greatest correlation with C3-Me changes (r=0.819, p<0.01), while the changes at the level of retrolingual airway space (PAS-t) demonstrated the greatest correlation with C3-I changes (r=0.693, p<0.01). Regression analysis was used to create predictive equations for PAS changes using these correlated factors

Effect of Surface Sealant Coating and Beverages on Color Stability of Provisional Restorative Material

2023-10-02T11:29:53+07:00

The study aimed to investigate the effect of surface sealant coating agent on color stability of Bis-acryl composite resin after immersing in different beverages at various times. Ninety-six disc-shaped specimens were prepared from Bis-acryl composite resin (Luxacrown). The specimens were randomly divided into 2 groups: the non-surface sealant coating group (Group1) and the surface sealant coating group (Luxatemp-Glaze and Bond) (Group2). Twelve specimens of each group were assigned for immersion in distilled water (DW), red wine (RW), coffee (CF) and Coca-Cola (CC). All specimens were immersed in the beverages and stored in an incubator. The color change (∆E) was measured after immersing for 7, 30 and 150 days with a spectrophotometer, according to the CIELAB system. Data were analyzed statistically with mixed-design ANOVA. Group 1 showed more mean color change in red wine and coffee (p<0.05). In both groups, the color change of specimens immersed in coffee was significantly lower than that in red wine at each measurement time except day 150 in Group 1. Moreover, the types of beverages affected mean color change of all three immersion times. In conclusion, surface sealant coating, type of beverages and various immersion time affect the color stability of provisional restorative materials.

The Comparison of The Micro Push-Out Bond Strength of AH Plus, Endosequence BC, and MTA Fillapex Sealers: A Laboratory and Finite Element Analysis Study

2023-12-06T10:50:09+07:00

This laboratory study aimed to evaluate the micro push-out bond strength of 3 sealers: AH Plus, Endosequence BC, and MTA Fillapex. The Finite Element Analysis (FEA) was built and estimated micro push-out bond strength to the laboratory. Thirty extracted single-rooted lower premolars were instrumented and divided into 3 groups. All root canals were obturated by warm vertical compaction technique using a match gutta-percha cone and 3 different sealers: AH Plus, Endosequence BC, and MTA Fillapex (n=10 roots/ group). After 2 weeks incubation at 37^oC and 100% humidity, three slices of 1±0.1 mm-thickness were cut 3 locations: coronal, middle and apical, for the push-out bond strength test. The failure mode of the sample was examined under 10x magnification. Three samples size 2x2x25 mm of each sealer were prepared and tested for modulus of elasticity, and then the FEA results analysis was created under ANSYS workbench. The micro push-out bond strength was analyzed using one-way ANOVA, and the correlation between the laboratory and FEA was evaluated by the Pearson correlation test. The significance was set at p<0.05. Results of the laboratory test showed that AH Plus and Endosequence BC sealers had a superior micro push-out bond strength compared to the MTA Fillapex sealer (p<0.001), but there was no statistically significant difference between the AH Plus and the Endosequence BC sealer (p>0.05). For the FEA, AH Plus presented the highest maximum micro push-out bond strength at the coronal dentine, followed by Endosequence BC and MTA Fillapex sealer (2.48, 2.16 and 1.23 MPa, respectively). The same results were found at middle dentine (2.19, 2.09 and 0.70 MPa, respectively), and at apical dentine (1.72, 1.63 and 0.43 MPa, respectively). The micro push-out bond strength from the laboratory and FEA had highly positive relationship (r=0.869). In conclusion, Endosequence BC exhibited a micro push-out bond strength comparable to AH Plus, surpassing MTA Fillapex sealer. The FEA test presented a highly positive correlation in micro push-out bond strength with laboratory testing.

Masking Efficiency Measurement of Resin Composite Using Human Eyes Compared with A Spectrophotometer

2023-12-01T14:32:11+07:00

The masking efficiency of resin composite affects the aesthetics of dental restorations. There are several methods for measuring color masking. Using the human eye has the advantage of being easy to perform, but the drawback is that it is unreliable. Using a spectrophotometer has the advantage of being more accurate, but it can be more challenging to use. In clinical practice, color selection for dental restorations is often done using the human eye. This research compared the masking efficiency measurement of the human eye and a spectrophotometer. Two resin composites, Clearfil AP-X shade A2 and Metafil CX shade A1, with 0.5-, 1-, 1.5-, and 2-mm thickness levels, were restored to measure color masking using the human eye and a spectrophotometer. The results were analyzed using Sum masking values obtained from the human eye and ∆E values obtained from the spectrophotometer. It was found that both values were correlated. In summary, the masking efficiency measurement of the human eye corresponds to the spectrophotometer. The Metafil CX resin composite has higher masking efficiency than the Clearfil AP-X in achieving an aesthetically acceptable shade.

Incidence and Risk Factors for Postoperative Pneumonia (POP) after Major Oral and Maxillofacial Surgery

2024-01-18T15:57:23+07:00

Postoperative pneumonia (POP) is a condition of lung inflammation that occurs after surgery, often resulting from a hospital-acquired or ventilator-associated lung infection within 48-72 hours of surgery. Previous studies have reported an 18.8% incidence of postoperative pneumonia after oral and maxillofacial surgery. However, there is no study in Thailand regarding the incidence of postoperative pneumonia after oral and maxillofacial surgery and the related risk factors. This research aimed to investigate the incidence and factors related to postoperative pneumonia after oral and maxillofacial surgery. This study is a prospective analytical study conducted by collecting data from a sample of 93 patients who underwent major oral and maxillofacial surgery at the Dental Hospital, Faculty of Dentistry, Khon Kaen University. The results showed that 10.8% of the sample had postoperative pneumonia. Risk factors associated with postoperative pneumonia included age over 55 years, surgery duration longer than 360 minutes, tracheostomy, and an ASA classification of 3 or higher. This study revealed that patients aged 55 years and older had a 27.75 times higher risk of developing postoperative pneumonia compared to younger patients, and those with surgery durations longer than 360 minutes had a 7.91 times higher risk. In conclusion, the incidence of postoperative pneumonia after oral and maxillofacial surgery is 10.8%. Patients aged 55 years and older have a 27.75 times higher risk of developing postoperative pneumonia compared to patients younger than 55 years. Additionally, patients with surgery durations exceeding 360 minutes have a 7.91 times higher risk of developing postoperative pneumonia compared to those with a shorter surgery duration.

Effect of Organic Fillers on The Surface Microhardness of Restorative Resin Composites

2024-03-27T09:59:25+07:00

This research aimed to study the effect of organic fillers on the surface microhardness of restorative resin composites. Forty resin composite specimens in the dimension of 4x4x2 mm³ were divided into four groups (n=10) according to the filler type: Fantasista V, Clearfil AP-X ES2, Clearfil AP-X, and Filtek Z350XT. Vicker hardness test (VHN) was carried out in all specimens with eight indentations, each with 100 g of loading for 15 s. The data were analyzed with one-way ANOVA and the Games Howell test. There were statistical differences between the groups of specimens (p<0.05) except Fantasista V and Clearfil AP-X ES2 (p>0.05). The maximal surface microhardness value was found in Clearfil AP-X, comprising of glass-based inorganic fillers. While the organic-filler based composites (i.e. Fantasista V and Clearfil AP-X ES2), had the lowest surface microhardness. However, they showed the better filler retention compared to the inorganic filler groups. In conclusion, organic fillers lessen the microhardness value but minimize filler dislodgement compared with inorganic fillers.

Microbial Air Contamination in Dental Clinics with Different Ventilation Systems

2024-03-28T17:06:07+07:00

The study aimed to compare the Total Viable Aerobic Count (TVACs) before and during dental procedures in two different ventilation systems, the first systems in a Pre-Upgrade Dental Clinic that has separated air conditioners and standing air purifiers, the second systems in a Special Dental Clinic, and a Post-Upgrade Dental Clinic, which have a centralized ventilation and air purifying systems, with the Index of Microbial Air Contamination (IMA). The data was collected the numbers of bacteria and fungi colony in blood agar (BA) and Sabouraud dextrose agar (SDA). The settle plates were placed 50 cm from a patient’s head, and 1 metre from the wall. Each sampling was placed 1 hour before and during dental procedures, for three days. The Result, in the Special Dental Clinic, the Pre-Upgrade Dental Clinic and the Post-Upgrade Dental Clinic TVACs before and during dental procedures were 71 and 46, 58 and 45, 93 and 15 CFU/dm2/hr, respectively. The Wilcoxon Sign-Rank test showed a statistically significant difference for each setting (p<0.001). Considering three days of data collection, The Kruskal Wallis test indicated that in the Special Dental Clinic (before and during dental procedure) and the Pre-Upgrade Dental Clinic (during procedure), TVACs showed no statistically significant difference. The TVACs showed statistically significant difference in the Pre-Upgrade Dental Clinic (before dental procedure) and the Post-Upgrade Dental Clinic (before and during dental procedure) (p<0.001) Conclusion, the IMA indicated “fair” for the Special Dental Clinic and the Pre-Upgrade Dental Clinic before and during dental procedures. In contrast, the Post-Upgrade Dental Clinic indicated “poor” before dental procedure and “good” in during dental procedure. The TVACs of 2 ventilation systems showed less TVAC during dental procedure than before dental procedure, with a statistically significant.

Fracture Resistance of Tunnel-Restored Teeth at Different Marginal Ridge Heights

2024-03-28T17:07:14+07:00

This study aimed to investigate fracture strength of restored tunnel-prepared teeth with different marginal ridge heights, using various adhesive systems and restorative materials. 130 intact premolars were randomly allocated into 13 groups based on 3 remaining marginal ridge heights (1.0 mm, 2.0 mm and 3.0 mm). 3 restorative systems (Optibond™ FL, selective enamel etching mode Single Bond Universal, Equia Forte Fil), positive control or tunnel prepared tooth without restoration, and intact unprepared teeth served as negative control. Tunnel preparation and restoration were performed. After 10,000 cycles of thermocycling, each specimen underwent fracture strength test and evaluated for mode of failure. The data were analyzed using two-way ANOVA, one-way ANOVA followed by a post hoc test. The results of the experiment showed that fracture strength values of tunnel restoration were significantly affected by remaining marginal ridge heights, but did not significantly affect by restorative systems. All restorative systems were unable to support tunnel preparation at remaining marginal ridge heights of 1.0 mm. At remaining marginal ridge heights of 3.0 mm, strength of tunnel preparation was equivalent to intact teeth or negative control. At remaining marginal ridge heights either of 2.0 mm or 3.0 mm, strength of tunnel restoration with Optibond™ FL, selective enamel etching mode Single Bond Universal, and Equia Forte Fil were as strong as intact teeth. It can be concluded that, tunnel restoration at remaining marginal ridge height of at least 2.0 mm with Optibond™ FL and paste-like bulk fill resin composite, selective enamel etching mode Single Bond Universal and paste-like bulk fill resin composite, or Equia Forte Fil was comparable to intact teeth.