Effect of ultrasonic and sonic instrumentation on shear bond strength of resin composite to enamel: An in vitro study.

PURPOSE: To assess and compare the effects of sonic and ultrasonic instrumentation on shear bond strength (SBS) and investigate the influence of adhesive system application modes (etch&rinse/self-etch) on SBS. METHODS: In this experimental study, 45 extracted sound human molars were selected. Mesial and distal surfaces of the teeth were abraded until 90 smooth enamel surfaces were obtained. Specimens were divided into two groups, with half (N= 45) conditioned in etch&rinse mode and the remaining (N= 45) in self-etch mode using Tetric N Bond Universal. Composite resin discs were produced on these surfaces by filling Teflon molds. All specimens were aged via thermocycling. Each group was further divided into three more groups (n= 15) according to the type of periodontal instrumentation (ultrasonic, sonic or none). SBS values were recorded and analyzed using two-way ANOVA. Fracture sites were examined under a stereomicroscope. RESULTS: The type of periodontal instrumentation had no significant effect on SBS values, whether sonic, ultrasonic or their absence (P= 0.945). The type of adhesive system mode had a significant influence on the shear bond strength values. Etch&rinse groups had significantly higher shear bond strength values than self-etch groups (P< 0.001). CLINICAL SIGNIFICANCE: This study reassures practitioners that sonic and ultrasonic instruments are safe for enamel bonding and highlights the importance of selecting adhesive techniques for optimal restorative outcomes.

Assessment of palatal mucosal thickness and location of the greater palatine foramen using cone-beam computed tomography: a retrospective study.

OBJECTIVES: This study aimed to measure the palatal mucosal thickness and examine the location of the greater palatine foramen using cone-beam computerized tomography (CBCT). METHODS: In this study, cone-beam computed tomography (CBCT) images of the maxillary posterior region of 120 subjects were evaluated. The palatal mucosal thickness (PMT), palatal width and depth, and location of the greater palatine foramen (GPF) were determined on CBCT. The differences in the palatal mucosal thickness according to gender and palatal width/palatal depth were analyzed. The location of the GPF related to the maxillary molars was noted. RESULTS: The mean palatal mucosal thicknesses from the canine to the second molar teeth were 3.66, 3.90, 4.06, 3.76, and 3.92 mm, respectively. The mean PMT at the second premolar was statistically thicker than at other regions (p < 0,001). There was no relationship between PMT and gender. However, the palatal depth and width of the males were greater than females. (p = 0.004 and p = 0.014, respectively) PMT in the low palatal vault group had statistically higher compared to the high palatal vault group. (p = 0.023) Greater palatine foramen was mostly observed between second and third molar teeth. (48%). CONCLUSIONS: According to our results, first and second premolar regions can be preferable in soft tissue grafting procedures for safe and successful treatment outcomes. The measurement of the thickness of the palatal mucosa and the evaluation of the greater palatine foramen location before the surgical procedures are essential steps to harvest from the ideal donor site and to achieve optimal surgical outcomes.

The effect of dental pulp stem cells and L-PRF when placed into the extraction sockets of impacted mandibular third molars on the periodontal status of adjacent second molars: a split-mouth, randomized, controlled clinical trial.

PURPOSE: To compare the clinical and radiographic effectiveness of dental pulp stem cells (DPSCs) seeded onto L-PRF and L-PRF alone in the extraction socket of mandibular third molars. METHODS: This study analyzed 13 patients who required surgical removal of impacted bilateral mandibular third molars. The main outcome measures were the probing pocket depth (PPD) and clinical attachment levels (CAL) that were recorded for the adjacent second molars (LM2) at the baseline and 6 months after surgery. The secondary outcomes were radiographic vertical bone loss (VD) and relative bone density (rBD) distal to the LM2. RESULTS: Twenty-six LM2s were evaluated. After 6 months, the L-PRF and L-PRF + DPSC groups showed a significant reduction in PPD (1.65 ± 1.01 mm and 1.54 ± 0.78 mm) and CAL (2.23 ± 1.45 mm and 2.12 ± 0.74 mm), respectively. There was no difference between the groups for any periodontal parameters. No significant differences were found between the groups regarding the VD or rBD at the sixth month. CONCLUSIONS: This study found that there was a significant improvement regarding the PPD, CAL, and VD measurements with the application of L-PRF, both alone and with the addition of DPSC, at the extraction socket. DPSC did not significantly contribute to the results compared to L-PRF therapy alone. TRIAL REGISTRATION: This study was registered on 23 December 2020 on ClinicalTrials.gov under the number NCT04641533.

Histomorphometric and biomechanical evaluation of the osseointegration around micro- and nano-level boron-nitride coated titanium dental implants.

INTRODUCTION: Titanium dental implants has been coated with different materials such as polymers and biomimetic agents, bone morphogenetic protein, calcium phosphate to enhance surface properties of the titanium implants for osseointegration. The aim of this study was to evaluate the bone tissue healing around Boron Nitride-coated (BN-coated) titanium implants histomorphometrically and biomechanically and also observe the effect of different coating thicknesses on osseointegration. MATERIALS AND METHODS: BN was coated on dental titanium implants with two different coating thicknesses by using RF magnetron sputtering system. Totally fifty-four implants were inserted into the tibias' of 12 New Zealand rabbits bilaterally under general anesthesia. All animals were sacrificed after 4-weeks. Bone-implant contact (BIC) and new bone area/total area ratios (BATA) were calculated. Also, the removal torque (RT) test was performed. RESULTS: The highest new bone area in the medullary cavity was around the nano-BN-coated surface with 15.70%. In micro-BN-coated surface and control group, this ratio was determined as 10.48% and 8.23%, respectively. The BIC ratios in upper-side of implants and cortical-associated BIC ratios in lower-side were found significantly higher in control and micro-BN-coated group than nano-BN-coated group (p < 0.05). Similar BIC values were observed between control and micro-BN-coated groups (p > 0.05). BATA values did not show statistically significant differences between all three groups (p > 0.05). The RT values measured in all groups were found comparable and no statistically significant differences were found (p > 0.05). CONCLUSION: No inflammatory reaction developed around any implant. Relatively more new bone formation around nano-BN-coated titanium implants indicates the promising osseoinductive effect of BN coating. BN-coated implants showed similar biomechanical and histomorphometrical outcomes to that of the conventional titanium implants through a 4-week evaluation period.

Evaluation of patients' perception of gingival recession, its impact on oral health-related quality of life, and acceptance of treatment plan.

Objective: Gingival recessions (GR) may cause aesthetic and hypersensitivity complaints which might affect oral health-related quality of life (OHRQoL). The aim of this study was to evaluate the patients' awareness of their own GR, the impact of GR on OHRQoL and the acceptance of suggested treatment modalities.Materials and Methods: This cross-sectional study was conducted with 205 patients. The demographic variables were recorded and patients' perception of GR was questioned. Full-mouth examination was carried out and clinical parameters were recorded. Gingival recessions, GR related complaints were evaluated and GR treatments were suggested and acceptance were also recorded by the examiner. The patients filled out OHRQoL-United Kingdom (OHRQoL-UK) questionnaire regarding to their GR and were asked if GR have/would have impact on oral health and if the GR will/would get worsen. Data was analysed with independent t test and Mann-Whitney U test.Results: 4819 teeth were evaluated and 733 GR examined in 147 patients. Fifty-seven patients were unaware of their GR. A strong belief that GR have impact on oral health (88.78%) and GR will progress (86.34%) was detected. Acceptance of treatment was increased and non-invasive modalities were preferred if patients had complaints. The awareness of GR status increases and the misperception decreases the OHRQoL-UK scores. The results revealed that hypersensitivity decreases the OHRQoL-UK scores and aesthetic concerns and hypersensitivity decreases the OHRQoL-UK physical scores significantly (p < .05).Conclusions: The results indicated that the patients might be unaware of their GR and the GR related factors may lead to poorer OHRQoL.

In Vitro Evaluation of Direct and Indirect Effects of Sonic and Ultrasonic Instrumentations on the Shear Bond Strength of Orthodontic Brackets.

OBJECTIVE: Sonic and ultrasonic instrumentations generate vibrations that may influence debonding characteristics. The objective of this in vitro study was to assess the direct and indirect effects of sonic and ultrasonic periodontal instrumentations on the shear bond strength (SBS) and the adhesive remnant index (ARI) scores of metallic orthodontic brackets. METHODS: Metallic brackets were bonded to 75 extracted mandibular central incisors that were embedded in acrylic resin. Instrumentations around the bracket base performed with ultrasonic (UltrasonicB group, n=15) and sonic (SonicB group, n=15) scalers were used to evaluate the direct effects on the SBS of brackets. Lingual surface instrumentations with ultrasonic (UltrasonicL group, n=15) and sonic (SonicL group, n=15) scalers were performed to assess the indirect effects. The control group (n=15) did not have any treatment. Instrumentations were performed for 30 s with 0° scaler tip angulations with settings recommended by manufacturers. The SBS of the brackets tested with a universal testing machine and ARI scores were recorded. Data were analyzed by Kruskal-Wallis and Mann-Whitney U tests. RESULTS: The mean SBS of the control group was significantly higher than that of the UltrasonicB and SonicB groups (p=0.008). The UltrasonicL and SonicL group instrumentations also decreased the SBS, although the difference was statistically insignificant. UltrasonicB instrumentations caused significantly higher frequency of ARI scores than the control group. CONCLUSION: The decrease of the SBS of metallic brackets indicates the influence of ultrasonic and sonic instrumentations on the breakage behavior at the bracket-resin interface. Instrumentations around the bracket base should be conducted with caution to decrease the bond failure risk of metallic brackets.

Effects of Renal Transplantation and Hemodialysis on Patient's General Health Perception and Oral Health-Related Quality of Life: A Single-Center Cross-Sectional Study.

BACKGROUND: Patients with end-stage renal disease have a lower quality of life compared to the general population. Oral health-related quality of life (OHRQoL) is of particular interest as good oral health could influence general health. This study aimed to compare dental and periodontal health status, OHRQoL, and general health perception of renal transplant (TX) and hemodialysis patients (HD) with that of healthy controls. METHODS: The study included 64 TX, 63 HD, and 61 healthy patients. TX patients were also grouped according to the time elapsed after transplantation and currently use of immunosuppressive agents. The numbers of decayed, missing, and filled teeth were recorded as DMFT, and periodontal health status was evaluated. Patients' general health perceptions and OHRQoL were assessed using Short Form-36, Oral Health Impact Profile-14, and OHRQoL-United Kingdom questionnaires. RESULTS: The HD groups presented significantly higher DMFT scores and periodontal scores than TX and control groups. OHRQoL-United Kingdom total scores of TX and HD groups were lower than controls (P < .05). Oral Health Impact Profile-14 total scores revealed that HD groups' OHRQoL was significantly lower than TX and control groups (P < .05). Perceptions of general health of TX patients were higher than in the HD group. CONCLUSIONS: Renal transplantation has shown to increase quality of life and OHRQoL compared to hemodialysis therapy. Neither the immunosuppressive agent nor the time elapsed after transplantation were observed to be significant factors affecting OHRQoL.

Methodological evaluation of gingival crevicular fluid volume and neutrophil elastase levels: sequential sampling, length of sampling time and two different sampling methods.

Objectives: The mechanisms underlying the formation and composition of gingival crevicular fluid (GCF) and its flow into and from periodontal pockets are not understood very well. The aim of this study was to evaluate the length of sampling time and sequential sampling of GCF neutrophil elastase (NE) enzyme levels by using intracrevicular and orifice methods.Material and methods: Twenty adults (mean age of 41.8 years, ranged 31-60 years, 18 males and 2 females) with chronic periodontitis were enrolled and all completed the 3-d study. GCF was collected by both intracrevicular and intrasulcular methods, 720 samples of GCF were collected. In first, second and third day, the length of sampling time in seconds (s) and order were '5- 10-30-s'; '10- 30- 5-s' and '30- 5- 10-s,' respectively. GCF elastase levels were determined by hydrolysis of neutrophil specific substrate N-methoxysuccinyl-Ala-Ala-Pro-Val-p-nitroanilide.Results: NE activity (µU) and NE activity/volume (µU/µl) were significantly different for order of sampling (p < .05), but not for the length of sampling time (p>.05).Conclusions: Within the limits of this study, the choice of sampling technique in GCF-profile studies seems to be a critical decision as it has the potential to affect the GCF volume and NE activity.

Osseous outgrowth on the buccal maxilla associated with piezosurgery-assisted en-masse retraction: A case series.

Piezoelectric surgery is a novel surgical approach used in orthodontic treatment for rapid tooth movement. This paper presents a case series wherein osseous outgrowths were observed in response to piezosurgery-assisted en-masse retraction. Sixteen patients requiring upper premolar extractions were treated with miniscrew-supported en-masse retraction and received minimally invasive decortication via piezosurgery. Computed tomography (CT) of the maxillary anterior region was performed to investigate the nature of the outgrowths. In 8 of the 16 patients, hemispheric or disc-shaped osseous outgrowths were observed on the sites where piezosurgery was performed during retraction. CT images revealed that these outgrowths were alveolar bone. This case series presents a previously unreported osseous response to piezosurgery-assisted tooth movement during orthodontic treatment. The response is mostly transient and is observed in 50% of the treated patients, suggesting a bone turnover that can be assessed clinically and radiographically.

Efficiency of piezosurgery technique in miniscrew supported en-masse retraction: a single-centre, randomized controlled trial.

BACKGROUND: Piezoelectric surgery is a newly introduced technique for rapid tooth movement. However, the efficiency of this technique has not been investigated on en-masse retraction cases yet. OBJECTIVE: To investigate the efficiency of piezosurgery technique in accelerating miniscrew supported en-masse retraction and study the biological tissue response. In addition, to show if this technique induces a difference in dental, skeletal and soft tissue changes on lateral cephalograms, and in canine and molar rotations, besides intercanine and intermolar widths on dental casts. DESIGN, SETTING, PARTICIPANTS: We conducted a randomized, single-centred, parallel-group, controlled trial, requiring upper right and left first premolar extractions on 30 patients above the minimum age of 14 years at the beginning of retraction. INTERVENTIONS: Piezosurgery-assisted versus conventional en-masse retraction anchored from miniscrews placed between second premolars and first molars, bilaterally. OUTCOMES: The main outcome was the en-masse retraction rate. Secondary outcomes were gingival crevicular fluid (GCF) volume and GCF content of receptor activator of nuclear factor κß ligand (RANKL), changes regarding cephalometric and dental cast variables, and miniscrew success rates. RANDOMIZATION: Accomplished with opaque, sealed envelopes. BLINDING: Applicable for data assessment only. RECRUITMENT: Commenced in February 2013 and ended in October 2014. RESULTS: Thirty-one patients were included in the study and divided into 2 groups of piezosurgery (n = 16) and control (n = 15). After 9.3 months of follow-up, no statistically significant difference was observed between groups for neither retraction rates (P = 0.958) nor GCF parameters (P > 0.05). Changes in lateral cephalometric and dental cast variables, and miniscrew success rates did not show significant differences either. CONCLUSION: Based on the results of this study, piezosurgery technique was found to be ineffective in accelerating en-masse retraction, and promoting a difference in the studied GCF parameters, skeletal and dental variables. REGISTRATION: The trial was not registered. PROTOCOL: The full protocol of this PhD thesis study can be accessed from tez.yok.gov.tr. FUNDING: This work was supported by Baskent University Research Fund. No conflict of interest was declared.