In vitro evaluation of surface roughness, adhesion of periodontal ligament fibroblasts, and Streptococcus gordonii following root instrumentation with Gracey curettes and subsequent polishing with diamond-coated curettes

The effect of surface roughening of orthodontic elastomers on hydrophobicity and in vitro adherence of Streptococcus gordonii

OBJECTIVES

Biofilm formation around orthodontic appliances causes gingivitis, enamel decalcification and caries. Bacteria adhere less readily to superhydrophobic surfaces. The aim of this study was to determine whether a superhydrophobic surface could be generated on orthodontic elastomers by surface modification in order to reduce bacterial adhesion.

MATERIALS AND METHODS

Orthodontic elastomers were modified with sandpapers of various grit sizes (80-600 grit). Surface roughness of the modified and unmodified surfaces was assessed qualitatively with scanning electron microscopy and quantitatively with confocal microscopy. Water contact angles were measured with a goniometer to quantify hydrophobicity. Measurements were performed on unextended elastomers (100% original length) and elastomers extended to 150%, and 200% of the original length. Adhesion of Streptococcus gordonii to saliva coated elastomers was measured by counting colony forming units on agar plates.

RESULTS

Abrasion with different sandpapers produced elastomers with surface roughness (Ra) ranging from 2 to 12 μm. Contact angles followed a quadratic trend with a maximum contact angle of 104° at an Ra of 7-9 μm. Average water contact angles, when viewed perpendicular to the direction of extension, decreased from 99° to 90° when the extension was increased from 100% to 200% and increased from 100° to 103° when viewed parallel to the direction of extension. Bacterial adhesion increased as roughness increased and this effect was more pronounced with elastomer extension.

CONCLUSION

The surface roughness of orthodontic elastomers influences both their hydrophobicity and bacterial adhesion. Superhydrophobicity of elastomers could not be achieved with sandpaper abrasion.

Complications and treatment errors in nonsurgical periodontal therapy

Nonsurgical periodontal therapy can be subject to iatrogenesis, which includes all the complications directly or indirectly related to a treatment. These complications include both operator-dependent harms and errors and the consequences and adverse effects of the therapeutic procedures. The complications arising following nonsurgical periodontal treatment can be categorized as intraoperative and postoperative and can affect both soft and hard tissues at an intra-oral and extraoral level. Soft-tissues damage or damage to teeth and restorations can occur while performing the procedure. In the majority of cases, the risk of bleeding associated with nonsurgical therapy is reported to be low and easily controlled by means of local hemostatic measures, even in medicated subjects. Cervicofacial subcutaneous emphysema is not a frequent extraoral intraoperative complication, occurring during the use of air polishing. Moreover, side effects such as pain, fever, and dentine hypersensitivity are frequently reported as a consequence of nonsurgical periodontal therapy and can have a major impact on a patient's perception of the treatment provided. The level of intraoperative pain could be influenced by the types of instruments employed, the characteristics of tips, and the individual level of tolerance of the patient. Unexpected damage to teeth or restorations can also occur as a consequence of procedural errors.

In vitro comparison of root surface roughness and bacterial adhesion following treatment with three different instruments

BACKGROUND

A novel device, piezoelectric 11 Gracey curet tip, reportedly combines benefits of a piezoelectric device and manual curet. The primary objective of this study was to compare root surface roughness outcomes between traditional manual curets and piezoelectric devices, as compared with this novel device. The secondary aim was to assess the level of adhesion of Streptococcus mutans on the root surface after instrumentation.

METHODS

The groups consisted of the following: 1) Gracey curet; 2) piezoelectric scaler; 3) piezoelectric 11 Gracey curet tip; and 4) untreated control. Root specimens were obtained from extracted human teeth and randomly assigned to each group. Surface roughness measurements (Ra and Rz) were taken with a profilometer before and after instrumentation. After instrumentation, root specimens were inoculated with S. mutans and biofilm was dislodged. Various dilutions of resuspended biofilm were incubated on blood agar plates and colony forming units (CFU) values were measured.

RESULTS

The experimental device resulted in significantly lower Ra and Rz compared with other groups (P < 0.01), and the Gracey curet was significantly lower than the piezoelectric tip and untreated control (P < 0.05). The Gracey curet and experimental device tip had significantly lower CFU values compared with the control (P < 0.05). There were no significant CFU value differences between the Gracey curet and both the piezoelectric and experimental device tips. There were no significant CFU differences between piezoelectric tip and both experimental device and control. There was no correlation between Ra and CFU values for Gracey curet, piezoelectric tip, or the control. However, correlation between Ra values and CFU approached significance for the experimental device (correlation = 0.66, P = 0.05).

CONCLUSIONS

Piezoelectric 11 Gracey curet tip is effective at resulting in a significantly smoother surface compared with traditional piezoelectric and hand instruments. CFU values with piezoelectric 11 Gracey curet tip were significantly lower than non-instrumented surfaces, but there were no significant differences compared with conventional methods.

Surface roughness of enamel and root surface after scaling, root planning and polishing procedures: An in-vitro study

Objectives

The aim of this study was to evaluate enamel and root surface roughness on exracted human teeth by using different tecniques (ultrasonic scaler, hand instruments, polishing paste, pumice and air powder system).

Materials and methods

A total of 200 samples were divided into two groups (enamel and root) randomly with 100 samples for each enamel and root groups. The groups were divided into 5 subgroups: Group I: ultrasonic scaler, group II: hand instruments, group III: polishing paste, group IV: pumice, group V: air-powder. Surface roughness (Ra) was assessed with Mitutoyo SJ-410 device. The one-way analysis of variance (ANOVA) test along with the Tukey test was used for statistical analysis. P values less than 0.05 were considered statistically significant.

Results

The use of ultrasonic scalers caused the highest roughness increase on the enamel surface (0.935 ​± ​0.010), whereas the use of pumice was the least (0.896 ​± ​0.018) (p ​< ​0.05). There was a significant difference between ultrasonic scalers and all the groups (hand instruments, polishing paste, pumice and air powder system) on enamel surface (p ​< ​0.05). Maximum surface roughness increase was observed in the ultrasonic scalers on root surface. There was a significant difference between ultrasonic scalers and polishing paste, pumice and air powder on root surface, respectively (p ​< ​0.05).

Conclusion

The use of ultrasonic scalers cause more rough enamel and root surfaces than hand instrumentation and polishing tecniques.

Clinical relevance

Uneven surfaces adversely affect the intended periodontal healing by creating a retention area of microbial dental plaque.

Biomaterial Properties Modulating Bone Regeneration

Biomaterial scaffolds have been gaining momentum in the past several decades for their potential applications in the area of tissue engineering. They function as three-dimensional porous constructs to temporarily support the attachment of cells, subsequently influencing cell behaviors such as proliferation and differentiation to repair or regenerate defective tissues. In addition, scaffolds can also serve as delivery vehicles to achieve sustained release of encapsulated growth factors or therapeutic agents to further modulate the regeneration process. Given the limitations of current bone grafts used clinically in bone repair, alternatives such as biomaterial scaffolds have emerged as potential bone graft substitutes. This review summarizes how physicochemical properties of biomaterial scaffolds can influence cell behavior and its downstream effect, particularly in its application to bone regeneration.

Calculus Removal and Root Surface Roughness When Using the Er:YAG or Er,Cr:YSGG Laser Compared with Conventional Instrumentation Method: A Literature Review

Objective: The purpose of this literature review was to evaluate the effectiveness of using Er:YAG (erbium-doped yttrium/aluminum/garnet) laser or Er,Cr:YSGG (erbium, chromium-doped yttrium/scandium/gallium/garnet) laser on calculus removal and their effect on the topography and roughness of root surface in comparison with the conventional instruments in the nonsurgical periodontal therapy. Background data: One of the most challenging problems in treatment of periodontal disease is the elimination of plaque and calculus, leaving a clean and smooth root surface to decrease plaque and calculus retention, and for good gingival reattachment. Materials and methods: PubMed and Google Scholar were searched for available literature. The electronic search was limited to articles published in the period between January 2007 and April 2017, in the English language. Results: A total of 47 publications fulfilled the inclusion criteria of this systematic review and screened according to the research questions. Calculus removal using the ultrasonic instrument showed remaining calculus compared with the hand instrument, whereas, on the contrary, erbium lasers revealed no remaining calculus or smaller amounts compared with the conventional instruments when used in appropriate settings. The results of this review showed that ultrasonic instrumentation produced effects on the root surface almost similar to that of hand instrumentation. Er:YAG laser and Er,Cr:YSGG laser clarify a little more surface roughness when compared with conventional instruments. Conclusions: The present systematic review indicates that a combination of scaling and root planing (SRP) using the erbium lasers as an adjunctive therapy at certain parameters can be appropriate to remove residual debris from the root surface and at the same time have little or no negative thermal effect on the root surface. The Er:YAG laser also seems to be the most suitable for nonsurgical periodontal therapy. Additional new good-designed studies are needed to evaluate the effectiveness of erbium lasers with SRP in nonsurgical periodontal therapy.

Comparative evaluation of manual scaling and root planing with or without magnification loupes using scanning electron microscope: A pilot study

Aim:

The aim of the present study is to compare the amount of remaining calculus, loss of tooth substance, and roughness of root surface after scaling and root planing with or without magnification loupes using scanning electron microscope.

Materials and Methods:

In the study, 30 teeth indicated for extractions due to severe chronic generalized periodontitis were included in the study. In test Group I, scaling and root planing was performed without magnification loupes, and in test Group II, scaling and root planing was performed with magnification loupes before extraction. In control Group III, no procedure was performed. After scaling and root planing, teeth were extracted followed by preparation of specimens. Specimens were then sent for scanning electron microscope study.

Results:

Statistically significant (P ≤ 0.05) differences were found among different test groups. Results showed that test Group II with magnification loupes had less remaining calculus and smoother surface with lesser amount of loss of cementum layer.

Conclusion:

From this, it was concluded that test Group II was more efficient in root debridement than test Group 1, so scaling and root planing done with magnification loupes will cause less damage to the tooth surface.

Clinical and laboratory evaluation of the effects of different treatment modalities on titanium healing caps: a randomized, controlled clinical trial

OBJECTIVES

The objective of this study is to evaluate the effects of treatment modalities on titanium surface characteristics and surrounding tissues.

MATERIALS AND METHODS

Eighteen participants each had four titanium healing caps (HC) attached to four newly inserted implants. After healing, each HC was randomly assigned to either (1) titanium curettes (TC), (2) stainless steel ultrasonic tip (PS), (3) erythritol air-polishing powder (EP), or (4) only rubber cup polishing (CON). Probing depths (PD), bleeding on probing (BOP), matrix metalloproteinase 8 (MMP-8), and periopathogens were recorded before and 3 months following instrumentation. After final assessments, HCs were removed, cleaned, and subjected to (a) bacterial colonization (Streptococcus gordonii, 24 h; mixed culture, 24 h) and (b) gingival fibroblasts (5 days). HC surfaces were analyzed with a scanning electron microscope (SEM).

RESULTS

No significant differences between the groups were evident before or after instrumentation for PD and BOP (except TC showed a significant decrease in PD; p = 0.049). MMP-8 levels and bacterial loads were always very low. MMP-8 decreased further after instrumentation, while bacteria levels showed no change. No significant differences (p > 0.05) were evident in bacterial colonization or fibroblast attachment. A comparison of the overall mean SEM surface roughness scores showed a significant difference between all groups (p < 0.0001) with the lowest roughness after EP.

CONCLUSIONS

All treatments performed yielded comparable outcomes and may be implemented safely.

CLINICAL RELEVANCE

Clinicians may fear implant surface damage, but all instrumentation types are safe and non-damaging. They can be implemented as needed upon considering the presence of staining and soft and hard deposits.

Removal of simulated biofilm: an evaluation of the effect on root surfaces roughness after scaling

BACKGROUND

Despite the development of less invasive devices, a debate exists about the benefits and risks of hand versus powered root surface instrumentation used in supportive periodontal therapy (SPT). The aim of the in vitro study was to differentially compare plaque removal efficacy and root surface roughening of newly developed sonic, ultrasonic scaler, and curettes in the hands of experienced versus less experienced operators.

MATERIALS AND METHODS

Sonic (AIR), ultrasonic devices (TIG), and double-gracey curettes (GRA) were utilized by seven experienced (EO) and four less experienced operators (LO) for root surface instrumentation of standardized plastic teeth on manikins' heads in a randomized sequence. The proportion of residual simulated plaque (RSP area in %) was planimetrically assessed, and the average root surface roughness produced (Ra and ∆Ra in μm) was measured by a precision profilometer.

RESULTS

The uninstrumented root surfaces showed a Ra of (median (Q25/Q75)) 1.00 μm (0.83/1.16). Following instrumentation, EO left significantly less RSP than LO regardless of the used instruments (20.00 % (10.00/34.00) vs. 26.00 % (12.00/44.00) p < 0.001), whereas the ∆Ra values (0.29 μm (-0.04/0.96) vs. 0.35 μm (-0.04/1.01), p = 0.237) failed to show significant differences. The surface roughness was higher with GRA followed by AIR then TIG regardless of operators' experience (p < 0.001).

CONCLUSION

Within the limits of the present study, the sonic device was most efficient in plaque removal, while the ultrasonic device produced the least surface roughness.

CLINICAL RELEVANCE

All three tested instruments seem effective in the mechanical root debridement during SPT, whereat the ultrasonic device show the smoothest root surface of all.

Characteristics of the molar surface after removal of cervical enamel projections: comparison of three different rotating instruments

Purpose

The aim of this study was to evaluate and compare tooth surface characteristics in extracted human molars after cervical enamel projections (CEPs) were removed with the use of three rotating instruments.

Methods

We classified 60 extracted molars due to periodontal lesion with CEPs into grade I, II, or III, according to the Masters and Hoskins’ criteria. Each group contained 20 specimens. Three rotating instruments were used to remove the CEPs: a piezoelectric ultrasonic scaler, a periodontal bur, and a diamond bur. Tooth surface characteristics before and after removal of the projections were then evaluated with scanning electron microscopy (SEM). We analyzed the characteristics of the tooth surfaces with respect to roughness and whether the enamel projections had been completely removed.

Results

In SEM images, surfaces treated with the diamond bur were smoothest, but this instrument caused considerable harm to tooth structures near the CEPs. The piezoelectric ultrasonic scaler group produced the roughest surface but caused less harm to the tooth structure near the furcation. In general, the surfaces treated with the periodontal bur were smoother than those treated with the ultrasonic scaler, and the periodontal bur did not invade adjacent tooth structures.

Conclusions

For removal of grade II CEPs, the most effective instrument was the diamond bur. However, in removing grade III projections, the diamond bur can destroy both adjacent tooth structures and the periodontal apparatus. In such cases, careful use of the periodontal bur may be an appropriate substitute.