Periodontal disease is an inflammatory disease caused by gram-negative anaerobic bacteria. This disease progresses because of disruption of the balance between the bacterial pathogenicity and biological defenses. Lactoferrin is a multifunctional iron-binding glycoprotein with a molecular weight of approximately 80 kDa. It has been shown to exert antibacterial effects and to inhibit the formation of biofilms by periodontal pathogens. However, the direct effects of lactoferrin on the periodontal tissue remains unknown. In this study, we investigated the effects of lactoferrin on human gingival fibroblasts (HGFs). DNA microarray analysis indicated that lactoferrin modifies the expression levels of gene groups involved in cell development, formation, and migration. Moreover, as HGFs express low-density lipoprotein (LDL) receptor-related protein 1 (LRP1), a lactoferrin receptor, it was found that the proliferation and wound healing abilities of HGFs were increased by treatment with lactoferrin. Activation of extracellular signal-related kinase 1/2 (ERK1/2) phosphorylation was increased by lactoferrin. Our results suggested that lactoferrin increased activation of ERK1/2 and promoted the proliferation of HGFs, enhancing wound healing. Therefore, we suggest that lactoferrin is a promising agent for supporting the repair function of gingival fibroblasts.

Gingival hyperplasia is well known to occur as an adverse effect of antihypertensive drugs, anticonvulsants, and immunosuppressants. Herein, we report a case of comprehensive periodontal treatment in a patient with severe drug-induced gingival hyperplasia accompanied by malaligned teeth and occlusion collapse caused by intake of a Ca-channel blocker (as an antihypertensive) for over 10 years, in which marked improvement of the periodontal condition was confirmed. Changing the antihypertensive drug (Ca-channel blocker) was not possible because the drug proved essential for good control of the blood pressure, but the supportive periodontal therapy was able to prevent recurrence. The periodontal condition has been well maintained post treatment.

Periodontal treatment is a frequently performed treatment in dental practice. However, use of invasive procedures entails the risk of bacteremia. Patients with a history of cardiovascular surgery with bacteremia are at an increased risk of developing endocarditis. Therefore, management of oral hygiene is indispensable to prevent the development of infective endocarditis.

We report a clinical case of severe periodontitis in a patient with a history of valve replacement surgery who received non-surgical periodontal treatment. The patient, who was 67 years old at the first visit, presented with the chief complaint of mobility of the lower anterior teeth. We diagnosed chronic periodontitis, and planned to treat the periodontal disease after consulting the department of internal medicine. The patient did not have much experience in dental treatment and had a phobia for dental treatment. We needed to improve his oral environment. However, he had paralysis of the dominant hand, which made brushing difficult. During periodontal basic treatment, professional care was provided two to three times a week. As a result, plaque control record could be maintained within the 20% range, and periodontal surgery was unnecessary without any need for recourse to periodontal surgery. It is worth noting that maintenance of a good course is possible even in patients receiving periodic non-surgical treatment, and while preventing in abeyance complicating health problems.

Case overview: The authors report here a case in which the lip repositioning technique was used to correct a gummy smile caused by hyperactive upper lip, which was followed for one year and resulted in a satisfactory outcome. The patient was a 24-year-old female who presented with a chief complaint of excessive gingival display. She had no systemic health issues, and no inflammation of the gingiva was observed. When she smiled, 8 mm of the gingiva was exposed above the maxillary anterior teeth. Based on clinical test findings, she was diagnosed with gummy smile caused by hyperactive upper lip.

Treatment plan: Prior to carrying out lip repositioning, a reversible trial was conducted in which no tissue was resected. The patient was observed for one week, after which a decision was made to carry out lip repositioning.

Course of treatment and treatment outcome: The modified lip repositioning technique was performed, which avoids postoperative left-right asymmetry by preserving the upper labial frenum. Following surgery, the patient was instructed to limit movement of the lips. When the stitches were removed one week later, the patient was experiencing pain, swelling and subcutaneous bleeding. One month later, the symptoms had disappeared, and exposure of the gingiva above the maxillary anterior teeth was improved 8 mm to 1 mm when the patient smiled. No complications such as asymmetry of the lip were observed. The patient was followed for one year, during which no regression was observed, and made steady progress that resulted in a high degree of patient satisfaction.

Discussion and conclusion: Gummy smile presents aesthetic problems. There are various treatment methods by which gummy smile can be addressed, and there is room for debate regarding cases in which the lip repositioning technique can be applied and the long-term prognosis. Conducting a reversible trial enables better anticipation of the outcome, and if based on an accurate diagnosis, the lip repositioning technique offers advantages compared to prosthodontics and surgical orthodontic treatment in terms of treatment period, invasiveness and other factors.