Gingival overgrowth and dental alveolar alterations: possible mechanisms of cyclosporin-induced tooth migration. An experimental study in the rat

Clinical presentation and management of drug-induced gingival overgrowth: A case series

BACKGROUND

We report three patients with drug-induced gingiva overgrowth (DIGO) caused by nifedipine, a calcium channel blocker, who were treated and followed up for 1–3 years. We discussed their symptoms, treatment process, treatment prognosis, and follow-up results.

CASE SUMMARY

All the patients had a history of nifedipine treatment to control hypertension. Besides nifedipine, Patient 1 was prescribed immunosuppressant cyclosporine A to control nephritis, which is also implicated in GO. Thus, we assumed that a synergistic effect between the drugs contributed to the severity of Patient 1’s condition. This condition has been reported to be more pronounced in patients with periodontitis. In the course of treatment, Patients 1 and 2 did not stop or change drugs. After initial periodontal treatment, periodontal surgery, and later periodontal support and better plaque control, their gingival hyperplasia was well managed and controlled. Under the guidance of a physician, Patient 3 replaced her calcium-channel blocker drug with losartan potassium and hydrochlorothiazide tablets. She received initial treatment without surgery, obtaining a good curative effect.

CONCLUSION

Patients’ compliance, self-plaque control, and professional periodontal therapy have a vital role in treating and preventing the recurrence of DIGO.

Self-correction of pathologic tooth migration after nonsurgical periodontal treatment in a metabolic syndrome patient with severe periodontitis and drug-influenced gingival enlargement

Drug-influenced gingival enlargement (DIGE) and reduced bone support caused by periodontitis are two of the etiologic factors for pathologic tooth migration (PTM). Comprehensive management, including surgical, orthodontic, and prosthodontic treatment, is usually required for recovery from severe DIGE and PTM. An 85-year-old Taiwanese male with a history of hypertension and uncontrolled diabetes mellitus (DM) visited our dental department for severe gingival enlargement and spontaneous bleeding. He was diagnosed as having advanced periodontitis and DIGE. Remarkable PTM occurred on the front sextants of his dentition. The patient's DM was gradually controlled, and his calcium channel blocker treatment was substituted with a new regimen for 7 months. One year after nonsurgical periodontal treatment and reinforcing the patient's oral care, both DIGE and PTM were spontaneously resolved without any surgical or orthodontic intervention. We advocate the value of early diagnosis, improving patient's oral hygiene, and meticulous nonsurgical treatment for both DIGE and PTM.

Nonsurgical periodontal treatment and prosthetic rehabilitation of a renal transplant patient with gingival enlargement: a case report with 2-year follow-up

Background

Drug-induced gingival enlargement is a common condition which can be observed in patients taking immunosuppressive medications following organ transplant surgery. The disfiguring excessive tissue often hinders proper oral hygiene practices, therefore accompanied by periodontitis, tooth mobility, and even pathological tooth migration in extreme cases. This case report presents a conservative treatment protocol for a patient with the aforementioned conditions involving neither surgical nor orthodontic intervention. Few related studies have reported such a noninvasive protocol for managing these kinds of conditions.

Case presentation

A 51-year-old woman presented with bleeding gingiva, mobile teeth and complained of chewing difficulties. She had undergone renal transplant surgery 16 years prior to this dental visit and had been taking immunosuppressive drugs including cyclosporine ever since. After clinical and radiographic examinations, the patient was diagnosed with drug-induced gingival enlargement, pathological tooth migration, severe periodontitis, and missing teeth. Through careful and meticulous nonsurgical debridement, oral hygiene instruction, tooth extraction, and occlusal adjustment, the patient’s periodontium was restored to a healthy state without surgical intervention. Moreover, the patient’s chewing function was restored by means of removable partial dentures. Good adaptation of prostheses and satisfaction with overall treatment outcomes were reported.

Conclusions

Through proper diagnosis, treatment, and with good patient cooperation, complex systemic and dental problems can be managed conservatively without invasive surgeries to attain a stable periodontium and eventually, occlusal function could be restored.

Surgical and prosthetic treatment in an elderly patient affected by unilateral idiopathic gingival fibromatosis: a case report

OBJECTIVES

The aim was to present the diagnosis and treatment of a case of unilateral idiopathic gingival fibromatosis (IGF) in a geriatric patient.

BACKGROUND

IGF is a rare condition characterised by an enlargement of the attached and marginal gingivae with no obvious association to any causative factor. Gingival overgrowth causes inaesthetic changes and clinical symptoms such as speech disturbances, tooth movement, and occlusal problems.

MATERIALS AND METHODS

A 65-year-old female presented localised enlargement of mandibular gingiva, malpositioning of anterior mandibular teeth, and difficulty in speech and mastication. IGF also causes numerous aesthetic and psychological problems. Treatment consisted of multiple extractions, surgical therapy, and early prosthetic rehabilitation to restore function and appearance and to prevent recurrence.

RESULTS

Excellent aesthetic result and psychological benefit were achieved, and no fibromatosis recurrence was detected after 1 year following surgery.

CONCLUSION

Gingival resection of the tissue excess and early oral rehabilitation with removable dentures have so far greatly improved patient's quality of life.

Effect of cyclosporine-A on orthodontic tooth movement in rats

OBJECTIVE

The objective of this study is to examine the effect of cyclosporine-A (CsA) on the rate of orthodontic tooth movement in rats.

SETTING AND SAMPLE POPULATION

This is a randomized controlled trial with a split-mouth design in Sprague-Dawley rats.

MATERIAL AND METHODS

Eighteen rats, divided at random in two groups, were fed with 8 mg/kg CsA (experiment) or mineral oil (control) daily after initial healing of bilateral maxillary second molar removal. All rats received orthodontic coil springs (10 cN) secured to the maxillary incisors and first molars at the rights side, while no springs were placed at the left. Distances between first and third molars were measured on days 0, 3, 6, and 12. After sacrificing on day 12, the alveolar ridges of the maxillae were sectioned and blood samples were collected for serum tartrate-resistant acid phosphatase (TRAP)-5b level detection and for histology, respectively.

RESULTS

Significantly larger changes in intermolar distances were found after orthodontic force application in the CsA group at days 3 and 12 when compared with the control group. The inter-radicular dental alveolus of CSA-fed rats was osteopenic. Significantly increased TRAP-5b serum level was noted in the CsA group when compared with the control group.

CONCLUSIONS

We suggest that CsA enhanced the rate of orthodontic tooth movement. The osteopenia and the increased osteoclastic activity could be the underlying factors.

Effect of Cyclosporin A on the Expression of Inducible Nitric Oxide Synthase in the Gingiva of Rats

BACKGROUND

The role of nitric oxide (NO) in the pathogenesis of cyclosporin A (CsA)-induced gingival overgrowth is still unknown. The purpose of this study was to evaluate the effect of CsA on the expression of nitric oxide synthases (NOS) in the gingival tissue of rats.

METHODS

Thirty male Sprague-Dawley rats were randomly assigned to a control and two test groups. Rats in each group received CsA (0, 10, or 30 mg/kg) daily by gastric feeding for 4 weeks. The plasma NO and the NOS enzyme activities were assayed at week 4 in the blood samples and in the gingiva and lung tissue specimens, respectively. The distribution of inducible nitric oxide synthase (iNOS) was further evaluated in tissues obtained from the gingiva and lung at the end of weeks 1 and 4 by immunohistochemistry.

RESULTS

In the CsA-treated animals, increased levels of plasma nitrites/nitrates were measured in comparison to those in control rats. Significantly greater iNOS enzyme activities were detected in lung and gingival tissues obtained from CsA-treated animals than from control animals. In addition, cells positively staining for iNOS were clearly observed in both gingival and lung tissues obtained from the CsA-treated animals by immunohistochemistry, whereas a few stained cells were found in those from the control group. The quantity of cells positively stained for iNOS was greater in tissue from week 4 than week 1.

CONCLUSIONS

The effect of CsA on gingival iNOS expression was evaluated in rats for 4 weeks. A greater iNOS expression in the gingiva was observed after CsA therapy by both enzyme activities and immunohistochemica staining. Therefore, we suggest that CsA can increase gingival iNOS expression, which may play an important role in cyclosporin-induced gingival overgrowth.

Long distance selective fiber outgrowth of transplanted hNT neurons in white matter tracts of the adult rat brain

Terminally differentiated neurons derived from a human teratocarcinoma cell line (NT2N or hNT neurons) are promising as a cell source for transplantation, as they have been shown to be safe for transplantation in humans. We have shown previously that hNT neurons can express a catecholaminergic phenotype in a rat Parkinson model. In this study, we investigated the long-term survival and ability of hNT neurons to express tyrosine hydroxylase and reconstruct the dopamine-denervated nigrostriatal pathway. Hemiparkinsonian rats received grafts of 400,000 viable hNT neurons into each of the denervated striatum and substantia nigra. Robust hNT grafts were detected up to 24 weeks posttransplantation, although few cells expressed tyrosine hydroxylase. Many hNT fibers were often associated with ipsilateral and contralateral white matter tracts--corpus callosum, rostral migratory stream, optic tract, and external capsule. Fewer fibers were associated with the superior cerebellar peduncle, medial lemniscus, and nigrostriatal pathway. Axons also projected into the frontal cortex and extended parallel to the surface of the brain in the superficial cortical layers. These pathways were seen in all grafted animals, suggesting that specific guidance cues exist in the adult brain governing hNT fiber outgrowth. Injured adult axons and transplanted embryonic neuronal axons rarely extend for such distances in the adult nervous system. We propose that elucidating the factors promoting and guiding hNT axonal outgrowth could provide important clues to enhancing regeneration and target reinnervation in the adult brain, two factors of critical importance for cell restoration strategies aimed at brain repair.

Pathologic Tooth Migration

Pathologic tooth migration (PTM) is a common complication of moderate to severe periodontitis and is often the motivation for patients to seek periodontal therapy. In this review of the literature, available information concerning prevalence, etiology, treatment, and prevention of pathologic tooth migration is summarized. Prevalence of PTM among periodontal patients has been reported to range from 30.03% to 55.8%. A survey of the literature regarding chief complaints of periodontal patients support these high prevalence findings. The etiology of PTM appears to be multifactorial. Periodontal bone loss appears to be a major factor in the etiology of PTM. Many aspects of occlusion can contribute to abnormal migration of teeth, and more than one of those factors may be present in an individual patient. Soft tissue forces of the tongue, cheeks, and lips are known to cause tooth movement and in some situations can cause PTM. Also considered important in the etiology of PTM is pressure produced from inflammatory tissues within periodontal pockets. Because extrusion is a common form of PTM, clinical observations support the theory that eruption forces sometimes play a role in the etiology of PTM. Many oral habits have been associated with PTM which are often difficult for the therapist to detect. Most cases of severe PTM require a team approach to achieve success. Periodontal, orthodontic, and prosthodontic treatment are often required. Many patient variables enter into the selection of treatment for PTM. In early stages of PTM, spontaneous correction of migrated teeth sometimes occurs after periodontal therapy. Light intrusive forces are used successfully to treat extrusion and flaring forms of PTM. Based on the literature reviewed, it appears that many cases of PTM could be prevented through the early diagnosis and treatment of periodontal disease, occlusal contributing factors, gingival enlargement, and oral habits.

Periodontal changes in liver cirrhosis and post-transplantation patients. II: radiographic findings:

BACKGROUND

Liver disease and transplantation affect bone turnover. The role of cylosporin A (CsA) in aggravating bone loss is controversial. The aim of the present study was to examine the effect of liver cirrhosis, transplantation, and immunosuppressive therapy with either CsA or tacrolimus on alveolar bone height.

METHODS

The experimental group consisted of 13 liver cirrhosis (LC) patients. A second experimental group included 24 post-liver transplantation patients (PT) receiving CsA or tacrolimus. Seventeen healthy subjects formed a control group. Panoramic x-rays were taken and digitized using a computer-based measurement software to assess alveolar bone height of all available teeth.

RESULTS

Bone loss in the PT group (4.57+/-0.56 mm) was significantly higher than the control (C) (2.73+/-0.38 mm); however, it was significantly lower (P = 0.0005) than the LC (6.47+/-0.75 mm). Likewise, alveolar bone loss showed a trend for negative correlation (R = 0.404, P = 0.06) with the duration of immunosuppressive therapy post-liver transplantation.

CONCLUSIONS

Liver cirrhosis patients demonstrated greater bone loss compared to healthy controls. Restoration of liver functions following transplantation seems to have the potential to reverse some of these radiographic changes. Further longitudinal studies will be necessary to substantiate these findings.

Prevalence and risk of gingival enlargement in patients treated with nifedipine

BACKGROUND

Gingival enlargement is a known side effect of nifedipine use. This study was conducted to determine the prevalence and risk factors for gingival enlargement in nifedipine-treated patients.

METHODS

A cross-sectional study was conducted in a primary care center. Data from 65 patients taking nifedipine were compared with 147 controls who had never received the drug. All patients were examined for the presence of gingival enlargement using 2 different indices: vertical gingival overgrowth index (GO) in 6 points around each tooth, and horizontal MB index in the interdental area. Gingival index, plaque index, and probing depth were also evaluated.

RESULTS

The prevalence of gingival enlargement was significantly higher in nifedipine-treated cases than in controls (GO index, 33.8% versus 4.1%; MB index, 50.8% versus 7.5%, respectively). Higher gingival and plaque indices were observed in patients taking nifedipine. Among the possible risk factors, only the gingival index showed a significant association with gingival enlargement. The risk (odds ratio [OR]) of gingival enlargement associated with nifedipine therapy was 10.6 (3.8-29.1) for the GO index and 14.4 (6-34.6) for the MB index. Gingival index-adjusted ORs were 9.6 (3.3-28.1) and 9.7 (3.9-23.3), respectively. In the subset of high nifedipine exposure patients, the odds ratio for gingival enlargement increased to 17.4 (5.3-56.3) for the GO index and 23.6 (7.7-72.3) for the MB index. The concordance between GO and MB indices showed a kappa value of 0.689 in controls and 0.642 in patients treated with nifedipine.

CONCLUSIONS

Patients taking nifedipine are at high risk for gingival enlargement, and gingivitis acts as a predisposing factor.

Effects of cyclosporin A on dental alveolar bone: a histomorphometric study in rats

BACKGROUND

We have previously reported cyclosporin A (CA)-induced osteopenia around the dental alveoli of the mandibular incisors of rats. The drug-induced tooth displacement and the regional anatomical complexity around the mandibular incisors might complicate the local effects of CA. Therefore, the purpose of this study was to evaluate the dental alveolar bone histomorphology around maxillary secondary molars in CA-treated rats and to further elucidate the effects of CA on the dental alveolus.

METHODS

Twenty Sprague-Dawley rats were assigned to a CA and a control group. Animals in the CA group received CA (15 mg/kg) daily and the control rats received only mineral oil. At the end of weeks 2 and 4, five animals in each group were sacrificed. Dental alveoli around the maxillary second molar region were frontally sectioned and stained with toluidine blue by undecalcified histological processing. Ten serial tissue sections, 80 microm apart, were selected for histometric evaluation. Bone volume, bone-specific surface, and osteoid formation were measured at buccal, apical, and palatal locations in dental alveolus.

RESULTS

Overall bone mass in dental alveolus decreased more in the CA group than in the control group at both observation intervals. All histometric measurements, except the bone-specific surface, were significantly affected by the alveolar location (palatal, apical, and buccal) and CA therapy (P= 0.004 and <0.001, 0.001 and <0.001, 0.004 and <0.001 for drug therapy and location of the dental alveolus in bone volume, marrow volume, and the ratio of bone surface to volume, respectively). Decreased bone volume, but increased marrow volume, were noted in the CA group compared to the control group. Although the alveolar bone surface area did not differ between the CA group and the control group, greater alveolar surface-to-volume ratio was noted in the CA group. For osteoid, more decreased volume, seam width, and fractional formation surface were observed in the CA group compared to the control group (P <0.001, <0.001, and = 0.046 in osteoid volume, seam width volume, and formation surface, respectively).

CONCLUSIONS

Because the bone mass and the osteoid formation in the dental alveolus around the maxillary molar region showed a decrease after CA exposure, we conclude that this drug has inhibitory effects on the dental alveoli.