Topical Application Of Citric Acid Research Articles

Comparison of Effect of pH Modulation on Wound Healing with Topical Application of Citric Acid Versus Superoxide Ions.

Background:Wound healing is a dynamic process involving tissue repair and regeneration. Nonhealing and chronic wounds are a significant health problem that many patients all over the world are suffering from. Proper wound care is hence very important. Wound dressings have undergone continuous and significant changes over the time period. Optimal dressing should ensure a moist wound bed, help drainage, remove debris, and be anti-allergic and without immunogenicity.Objectives:The objective of the study is compare the effect of pH modulation on wound healing with topical application of citric acid versus superoxide ions. The aim is to study the efficacy and safety of citric acid versus superoxide ions in the prevention and control of infection and their effect on wound healing in similar wound types.Materials and Methods:We conducted randomized, prospective comparative study in a total of 100 patients admitted at Guru Nanak Dev Hospital, attached to Government Medical College, Amritsar. The patients were divided into two groups: Group A where wound management was done using superoxide ions and Group B where citric acid was used. A standard grading was done in terms of a decrease in wound size, an increase in granulation tissue, and a reduction in wound discharge.Results:The wounds treated with citric acid showed an average reduction in wound size of 73.43% by the 14th day as compared to 66.52% in the control group. The difference seen in the average reduction of wound size was statistically significant (P = 0.032). The wounds treated by citric acid application showed an average increase in granulation tissue of 56.66% as compared to 50.87% in the wounds treated by superoxide ions. The average hospital stay in patients of Group B was comparatively less than that of patients in Group A.Conclusion:Citric acid is safe and effective in all types of wound management and gives better efficacy and faster response as compared to superoxide ions. Citric acid promotes wound healing by the formation of granulation tissue and fibroblast proliferation.

Isolation and characterization of a molecule stimulatory to growth of somatic embryos from early stage female gametophyte tissue of loblolly pine

Loblolly pine (LP, Pinus taeda) is the primary commercial species in southern forests of the US. Somatic embryogenesis (SE) is an effective technique to implement clonal tree production of high-value genotypes from breeding and genetic engineering programs. Unlike angiosperm embryos with attached cotyledons as seed storage organs, the diploid conifer embryo is surrounded by the unattached haploid female gametophyte (FG). The FG is not present in culture. This presents a dilemma if the FG produces necessary or regulatory compounds for embryo growth, since in culture these important compounds would be missing and would have to be added as supplements. We report here the direct evidence that extracts from early-stage FG indeed stimulate early-stage somatic embryo (SME) growth and multiplication, whereas extracts from late-stage FG inhibit early-stage SME growth. Furthermore, we have now isolated this stimulatory substance from early-stage FG tissue, and identified this substance as citric acid on the basis of NMR and mass spectrometry. We then demonstrated that topical application of citric acid to SMEs stimulates embryo colony growth at P = 0.05. Moreover, we find that there is a good correlation between the amount of citric acid isolated from FG tissue (65 nmoles per stage 2-3 FG) and the amount of citric acid that stimulates colony growth (25-50 nmoles) when applied topically to SMEs. This approach of isolating and characterizing a molecule from plant tissue, and investigating its role on SE processes can provide valuable information leading to further applications of these molecules to improve LP SE protocols.

Does root surface conditioning with citric acid delay healing?

Effects of topical citric acid application on tissue maturation was studied in standardized periodontal defects in 6 beagle dogs. Following elevation of facial mucoperiosteal flaps, fenestration defects, 3 mm in diameter, were made through the cortical bone and recessed 0.5 mm into the dentin of maxillary canines. 1 defect in each dog was conditioned with a saturated solution of citric acid for 3 min and then rinsed with saline. Control defects in contralateral teeth were treated with saline only for the same length of time. The defects were covered with an expanded polytetrafluoroethylene membrane and the flaps repositioned and sutured. 14 days postsurgery, healing appeared more advanced along the defect walls and floor than in the center of the defect in all instances. Histometrically, citric acid-conditioned defects exhibited a higher density of collagen fibers along the defect walls and floor and adjacent to the barrier membrane as well as more advanced resolution of the residual blood clot than the surgical controls. Differences in fibroblast density within specimen pairs were non-significant. All control defects but none of the acid-conditioned defects showed an artifactual split between the dentin walls and the granulation tissue. This study failed to support the contention that topical application of citric acid to root surfaces may delay healing following periodontal surgery.

Pulpal response to topical application of citric acid to root dentin.

Abstract The purpose of the present study was to investigate the pulpal reactions to citric acid (pH 1.0) applied for 3 min to exposed root dentin. We used 48 roots of 24 maxillary and mandibular third and fourth permanent premolars from dogs divided equally into experimental (citric acid) and control (saline) roots. Following surgical exposure of the buccal root surface and the removal of the cementum with a Gracey curette, citric acid or saline was applied on the exposed dentin. The pulpal reactions were histologically evaluated 1, 7 and 15 days postoperatively using hematoxylineosin stained sections. Results obtained from 43 specimens showed no difference in the pulpal response at any of the observation intervals between citric acid and saline‐treated teeth.

Treatment of localized gingival recessions with coronally displaced flaps and citric acid. An experimental study in the dog.

The present study was designed to examine the effect of citric acid conditioning on the result of healing following treatment of localized gingival recessions with coronally displaced flaps. In 3 beagle dogs, localized gingival recessions were surgically created at the buccal surfaces of canines, premolars and molars. All experimental sites were allowed to accumulate plaque for a period of 6 months. Following preparation of notches in the buccal root surfaces at the level of the gingival margin, buccal and lingual mucoperiosteal flaps were raised. The exposed portion of the root surfaces was scaled and the cementum layer was removed. Another notch was prepared in the root surfaces at the level of the crest of the alveolar bone. Half the number of the roots were treated by topical application of citric acid while the remaining roots were used as non-acid treated controls. The flaps were sutured in a coronally displaced position. After 3 months of healing, the dogs were sacrificed and the jaws removed and placed in fixative. After decalcification, histological sections of the experimental roots and their periodontal tissues were produced. The 2 notches described above were used as reference points in the histological examination. The histological analysis disclosed that new attachment had formed on all test and control roots and extended in some specimens of both groups to a position coronal to the presurgical level of the gingival margin. The amount of new attachment was similar in the 2 categories of roots, demonstrating that citric acid conditioning did not produce additional new attachment.

Pulpal response to the topical application of citric acid following root planing in cats

The purpose of this study was to evaluate the pulpal reaction to topically applied citric acid (pH 1.0) following root planing procedures. Full-thickness mucoperiosteal flaps were reflected over the maxillary canines in six cats. The cervical portion of the buccal root surface was root planed and treated for 3 min with either citric acid (pH 1.0) or saline. The animals were killed after 3 days and block sections of the teeth obtained. Buccolingual serial sections of the teeth were prepared and evaluated for odontoblastic and inflammatory changes. Histological examination revealed normal pulpal structures in all experimental and control specimens.

New attachment formation on citric acid treated roots.

The present investigation was carried out in order to examine if citric acid treatment would promote new attachment formation on roots with a reduced but healthy periodontium. In each of 4 monkeys, periodontal tissue breakdown was induced around a maxillary and mandibular central incisor and second premolar or first molar by placing orthodontic elastic ligatures around the teeth. The ligatures were kept in situ until about 50% of the supporting tissues had been lost. Three months following removal of the ligatures the crown of the teeth was resected. The pocket epithelium and subjacent granulation tissue were excised and the periodontitis involved part of all roots was root planed using a diamond bur. Half the number of the teeth (7 teeth, i.e. II test roots) were treated by topical application of citric acid at pH 1 for 3 minutes. All roots were covered with a mucosal flap. The animals were sacrificed after 3 months of healing. The jaws were removed and tissue blocks containing the roots and their surrounding tissues were processed for embedding in paraffin. Serial sections, 8 μm thick, were cut in mesio‐distal direction for microscopic analysis. Six citric acid treated roots and 6 noncitric acid treated roots penetrated the covering soft tissue flap within the first week of healing. The microscopical analysis disclosed that in all roots new cementum with inserting collagen fibers had formed in the apical portion of the previously periodontitis involved surfaces. In those control roots, which for the entire length of the study remained covered by the oral mucosa, the coronal extension of this newly formed fibrous attachment amounted to an average of 1.0 mm with a range between 0.1 mm and 2.6 mm, and in the corresponding test roots 1.1 mm with a range between 0.1 mm and 2.2 mm. The length of the newly formed connective tissue attachment was significantly smaller in those test and control roots which had penetrated the soft tissue flap during healing than in those which remained covered throughout the study. No statistically significant difference was found between citric acid and non‐citric acid treated roots with respect to the amount of newly formed connective tissue attachment.

The effect of topical citric acid application on surgically exposed periodontal attachment.

The effect of topical citric acid application on surgically exposed periodontal attachment.

Fibrin linkage: a precursor for new attachment.

Previous studies indicated that connective tissue attachment to the root surface appeared to be dependent upon a chronologic healing sequence related to fibrin and collagen interactions. It was the purpose of the present study to try and substantiate this hypothesis by using histologic techniques designed to differentiate between fibrin and collagen during healing at the root surface interface. In four squirrel monkeys, 24 normal teeth were extracted and reimplanted after either (i) surgically denuding the coronal root surface of connective tissue fibers and cementum by root planing or, (ii) surgical denudation followed by topical application of citric acid (pH = 1; 3 minutes). Three specimens were available for histological analysis 1, 3, 7 and 21 days after reimplantation. Mallory's phosphotungstic acid hematoxylin staining technique was used to differentiate between fibrin and collagen. Epithelium migrated rapidly along the denuded, non-acid-treated, root surfaces, had reached the alveolar crest at 3 days, and was within the ligament space to the level of root denudation at 21 days. Epithelium did not migrate apically along denuded root surfaces treated with citric acid. At 1 and 3 days, inflammatory cells were enmeshed in a fibrin network which appeared to be attached to the root surface by arcade-like structures. At 7 and 21 days, the region had repopulated with connective tissue cells, and collagen fibers had replaced the fibrin. It was concluded that collagen fiber attachment to the root surface was preceded by fibrin linkage, and that the linkage process occurred as an initial event in the wound healing response.

Pilot clinical studies on the effect of topical citric acid application on healing after replaced periodontal flap surgery.

The effect of citric acid conditioning of the root surfaces during periodontal surgery was studied in 12 patients with residual pockets ≥ 5 mm two months following oral hygiene instruction and initial root planing. Full thickness, replaced flap procedure (“modified Widman”) was performed with or without topical citric acid application using a split mouth approach. Six months post‐operatively, improvement of the periodontal conditions was observed as evidenced from reduction of probing pocket depth, gain of probing attachment level and gingival recession. A mean probing attachment level gain for pooled acid treated surfaces of 2.1 mm was obtained as compared to 1.5 mm for the non‐acid treated control surfaces.Our previous dog and human studies have demonstrated new connective attachment after acid conditioning of root surfaces as contrasted to readaplation of a junctional epithelium in the non‐acid treated controls. However, the results of the present study indicate that from a clinical standpoint, the use of citric acid application might only provide a small improvement in probing attachment levels.

The effect of topical citric acid application on the healing of experimental furcation defects in dogs. III. The relative importance of coagulum support, flap design and systemic antibiotics.

Chronic periodontal disease was induced and through‐and‐through furcation pockets created in mandibular premolars in two groups of beagles consisting of five and six animals respectively. The furcation defects were treated by surgical debridement supplemented with citric acid conditioning of the instrumented root surface. The relative importance of three adjunctive therapeutic measures was assessed. Thus, the effect of systemic antibiotics was evaluated by inter‐group comparison. Gelfoam as a matrix support for the blood coagulum during healing was evaluated by intraindividual, contralateral comparisons in one group of animals. Coronal repositioning of the muco‐periosteal flaps was evaluated by contralateral comparisons in the second group of animals. Block specimens for histological evaluation were removed six weeks after surgery. A high rate of regeneration and new attachment of the furcations was obtained irrespective of the use of systemic antibiotics, Gelfoam and high or low flap positioning. Thus, topical acid application seems to be the crucial therapeutic factor in achieving new attachment in the present model of through‐and‐through furcation pockets.

The effect of topical citric acid application on the healing of experimental furcation defects in dogs. II. Healing after repeated surgery.

In a previous study, citric acid‐conditioning of the root surface greatly improved the rate of success of new‐attachment procedures in periodontal furcation pockets in mandibular premolars of Labrador retrievers (Crigger et al. 1978). In the present study, this experimental approach was tested in six beagles. The furcations on one side in each dog were reoperated six weeks after the first surgery. In 27 of the 35 treated teeth, mesiodistal sections showed closure of the furcation and new connective tissue attachment including deposition of new cementum. The extension of new attachment in the buccolingual dimension of the furcation, however, was not improved by repeating the surgical procedure.

Healing of periodontal connective tissues following surgical wounding and application of citric acid in dogs.

Topical application of citric acid to a root surface which has been scaled and root planed results in exposure of collagen fibrils of the dentin matrix. The purpose of this study was to examine the healing of gingival connective tissue adjacent to a root planed and subsequently acid conditioned root surface and to determine whether the exposure of dentin or cementum matrix collagen would facilitate the reestablishment of an attachment between the healing connective tissue and the root surface. Full thickness flaps were raised and labial alveolar bone removed over maxillary incisor roots of seven Labrador retrievers. The exposed root surface was planed before etching with citric acid (pH 1) for 3 min. The flap was then repositioned at its original level. Block sections were obtained after 7, 14, 21 and 42 days and the interface between the root surface and the healing wound tissue studied by light and electron microscopy. Compared to conventional flap surgery in the same animals, application of citric acid to the instrumented root surface resulted in an improved rate of connective tissue healing as well as a rapid and consistent reestablishment of connective tissue attachment through extensive interdigitation of new and old collagen fibrils at the tooth‐gingiva interface. Subsequent reinforcement of the established connective tissue attachment included recalcification of the acid‐affected dentin and deposition of new cementum.

Connective tissue regeneration to periodontally diseased teeth. A histological study.

A study was made to investigate the biological principle of new attachment of connective tissue to periodontally diseased root surfaces utilizing the previous finding that topical application of citric acid to the affected area may stimulate periodontal regeneration. Reconstructive surgery was performed on ten surfaces of nine teeth involved in advanced chronic periodontal disease. A muco‐periosteal flap was raised and the apical extent of existing subgingival calculus was demarcated by a notch made through the calculus and into the root. Following thorough instrumentation, a saturated solution of citric acid was applied to the root surface for five minutes and the flap repositioned and sutured. Four months later the teeth with attached periodontal tissues were removed and processed for histological analysis. Connective tissue regeneration characterized by deposition of new cementum, and more coronally, by tightly apposed soft connective tissue had occurred in all specimens. The junctional epithelium ended 1.2–2.6 mm coronal to the apical border of the notch in the various specimens. The results demonstrate that regeneration of periodontal tissues to a root surface that has become denuded as a result of chronic, destructive periodontal disease and that has been covered by calculus is, in fact, a biological possibility. This study does not establish whether or not acid conditioning of the root surface is a prerequisite for new attachment.

The effect of topical citric acid application on the healing of experimental furcation defects in dogs

Periodontal furcation pockets were created in the mandibular premolar teeth in eight Labarador retriever dogs. Six months later, a surgical debridement procedure aimed at closing the furcation defects was carried out. On either the right or left side in each dog, a cotton pledget saturated with citric acid (pH 1) was inserted into the furcation for 3 minutes. One tooth in each animal was left untreated. Block biopsies were removed after 6 weeks and processed for histological evaluation. All of the non‐acid treated and the unoperated teeth revealed a patent, epithelialized furcation defect, whereas 21 of 23 acid‐treated furcations showed closure of the furcation in mesio‐distal sections. The instrumented root surface was covered with a thin layer of cementum to which periodontal fibers were attached. The bone level was significantly higher in the acid‐conditioning of the root surface may increase the rate of success of new‐attachment procedures and does not seem to have an adverse dffect o soft tissue healing or bone regeneration.