Effects of citric acid and EDTA on periodontally involved root surfaces: a SEM study

Approaches to minimize tooth staining associated with silver diamine fluoride: A systematic review

OBJECTIVE

To the effectiveness of different strategies to overcome silver diamine fluoride (SDF)-mediated tooth staining.

MATERIALS AND METHODS

Four online databases (PubMed, ScienceDirect, Scopus, and Web of Science) were searched using different MeSH terms and Boolean Operators to retrieve the articles (until June 2021), followed by a hand-search of the reference list of the included articles. All full-text, original studies in English that evaluated SDF staining and at least one SDF modification/alternative were included.

RESULTS

Among the assessed studies, nine studies explored the stain-minimization effect of potassium iodide (KI) post-application following SDF treatment. Among these, eight concluded that KI application after SDF treatment significantly reduced tooth staining, while one showed marginal staining following glass ionomer restoration of the SDF-treated dentine. Additionally, one study applied potassium fluoride (KF) and silver nitrate (AgNO₃ ) concurrently to mitigate SDF-mediated staining. One study compared SDF staining with polyethylene glycol (PEG)-coated nanoparticles containing sodium fluoride (NaF), and another used nanosilver fluoride (NSF) for staining comparison with SDF.

CONCLUSIONS

Within the limitations of this study, the addition of different materials to SDF has proven to be a beneficial strategy for overcoming tooth staining associated with SDF. Future studies are warranted, particularly clinical trials, to validate these findings.

CLINICAL SIGNIFICANCE

SDF-mediated tooth staining is a serious concern that limits its clinical use. A review of various strategies to overcome this problem will help clinicians enhance its clinical use and patient acceptance.

Geomorphologic study of human tooth root surfaces following simulated avulsion by scanning electron microscopy

BACKGROUND/AIMS

Tooth avulsion is the most severe traumatic tooth injury. Immediate replantation after avulsion provides the highest success rate, whereas delayed replantation with dehydration for >1 h always results in ankylosis, replacement resorption, and eventual tooth loss. The aim of this study was to investigate the geomorphologic change of ultrastructure on tooth root surfaces due to dehydration.

MATERIAL AND METHODS

Twenty-four sound human premolars and fully developed third molars without periodontitis were selected for the experiment. Roots were separated into 6-7 pieces with an intact root surface area (3 × 3 mm² ) and then divided into the following groups: fresh group, prolonged dehydration groups (air drying for 1, 2, 4, 12, or 24 h), and dehydrated teeth (air drying for 2 h) treated with acid (Tris-HCl buffer or citric acid buffer). More than six pieces of root from each group were subjected to scanning electron microscopy (SEM) observation. Captured images were exported to ImageJ software to quantitatively analyze the areas covered with fibers. Statistical significance was determined by comparing the means of the different groups using t-testing or one-way analysis of variance followed by post hoc testing.

RESULTS

Fibrous "vegetation" covering the cementum was observed on the fresh root surface by SEM. This was destroyed by dehydration (>1 h), resulting in a root surface resembling the "Gobi Desert." The difference was statistically significant (p < .001). Root surface deteriorated by dehydration could be recovered by the re-use of the fibers embedded in the cementum as acid demineralization of the outer layer of cementum exposed the embedded fibers to simulate the geomorphology of fresh root surface.

CONCLUSIONS

Dehydrated teeth had deteriorated geomorphology of the root surface, which could be reversed by the re-use of the fibers embedded in the cementum using citric acid. Direct evidence from SEM gives new insights into the replantation of dehydrated avulsed teeth.

Oral Soft Tissue Grafting

The presence of healthy soft tissue at the tooth and implant interface correlates to long-term success and stability in function and esthetics. Grafting procedures utilizing various techniques can be performed during any stage of the implant or restorative therapy. Materials of autogenous, allogeneic, and xenogeneic sources are available for oral soft tissue grafting. This article describes the classifications of soft tissue defects, treatment modalities, and materials used to enhance soft tissue quality and quantity and to achieve optimal esthetics and function around teeth and implants.

The concentration of citric acid as dental root conditioner influences the behavior of fibroblasts from human periodontal ligament

OBJECTIVE

This study investigated the behavior of fibroblasts from human periodontal ligament (hPLF) cultured on dental roots subjected to different protocols of citric acid conditioning.

MATERIALS AND METHODS

32 human teeth extracted due to advanced periodontal disease provided 63 radicular fragments, which were randomly divided in groups according to the treatment given to the surface: rinsing with saline solution for 90 s (C), 10 % citric acid (CA10), or 50 % citric acid (CA50). The treatments were applied during 90 s, 120 s and 180 s (n = 9). hPLF were cultured for 24, 48 and 72 h (n = 3) on the treated samples and analyzed by scanning electron microscopy (SEM) for surface area covered by cells and dentinal tubules widening.

RESULTS

Excepting group C, all the other groups showed almost complete coverage of root surface by hPLF with time. At 24 h of cell culture, the largest area of coverage was seen in the samples treated with CA10-90 (98 ± 0.89 %) at 24 h of cell culture and this difference was significant (p < 0.05) in comparison to CA10-180 (84.04 ± 5.01 %), CA50-90 (63.28 ± 12.46 %), CA50-180 (56.59 ± 8.76 %) and C (0.06 ± 0.11 %). In all the other comparisons, there was no statistically significant differences between CA10 and CA50 (p > 0.05). Cells grown on surfaces treated with CA10 were more spread and flatten than in the CA50 specimens.

CONCLUSIONS

Periodontally compromised roots surfaces conditioned with 10 % citric acid for 90 s resulted in better substrate for hPLF proliferation, in initial periods of culture than 50 % citric acid. The enlargement of the dentinal tubules did not seem to be influenced by the acid concentration.

pH influences the biocompatibility of methylene blue solutions

OBJECTIVE

The aim of this study was to investigate the biocompatibility of methylene blue at different pH levels through the method of implantation in subcutaneous tissue.

MATERIALS AND METHODS

Eighty-four sterilized polyethylene tubes were allocated in the subcutaneous tissue of 28 rats, each one receiving four tubes, set into four groups: group tube (G-T)-empty tube, fibrin group (G-F)-tube filled with fibrin sponge, group methylene blue pH 7 (G-MB/pH 7)-tube filled with fibrin sponge soaked by methylene blue (100 μg/ml) at pH 7.0, and group methylene blue pH 1 (G-MB/pH 1)-tube filled with fibrin sponge and soaked by methylene blue (100 μg/ml) at pH 1.0. After 7, 15, and 30 days, seven animals from each group were euthanized, and the tubes involved by the surrounding tissue were removed and fixed with 4% buffered formaldehyde solution. The collected pieces were processed and histological sections (4 μm) were stained with hematoxylin and eosin and analyzed by light microscopy. Scores were assigned to analysis of histopathologic parameters. The results were statistically analyzed by the Kruskal-Wallis test (p ≤ 0.05).

RESULTS

At 7 and 30 days, the G-MB/pH 1 group showed no significant difference in the G-T control group, while G-MB/pH 7 had a significant increase on tissue reaction, also when compared to G-T. At 15 days, there was no statistical difference between the groups.

CONCLUSION

Within the limits of this study, it is concluded that methylene blue at pH 1.0 provides better biocompatibility than at pH 7.0.

Does chemical preconditioning contribute to the effectiveness of scaling and root planing? An in vitro pilot investigation

OBJECTIVES

A solution based on hypochlorite and amino acids was introduced to improve cleaning efficacy on the root surfaces. The purpose of this in vitro pilot study was to evaluate the time reduction and number of strokes required to clean untreated root surfaces in vitro.

METHODS

Sixty extracted human teeth displaying areas with subgingival calculus were assigned equally to one of three treatment groups (n = 20) according to the size of occupied areas, estimated by the number of pixels. The groups were assigned to either 30 s penetration time (I) or 300 s (II) or no pretreatment application (III). The weight for instrumentation was calibrated for a M25A curette (Deppeler/Switzerland) with 500 g. A new set of tools was used for each group, and each instrument was sharpened after single use by an EasySharp Device (Deppeler/Switzerland).

RESULTS

The time (in seconds) for instrumentation was recorded as follows: Group I: 32/23.5/50 (median/first quartile/third quartile); group II: 33/20/52.5; group III: 46.5/35.5/52.3. The results for the numbers of strokes were: Group I: 18/14.3/28; group II: 18.5/13/30.5; group III: 17.5/15/25. No statistically significant differences (P < 0.05) were found between the three groups for the variables 'time' and 'number of strokes'.

CONCLUSIONS

Within the limits of this in vitro pilot study, preconditioning of the calculus on root surfaces with an alkaline solution failed to reduce the number of strokes and time of instrumentation significantly.