Various bone matrix proteins are produced during the process of osteogenesis. Many previous studies suggested that the topography of an implant surface might affect the expression of osteoblast-mediated cytokines. However, these earlier studies were performed using in vitro cell culture. This study investigated the influence of the surface topography of a titanium implant placed under the periosteum on the gene expression of bone morphogenic markers in rat. Six custom-made implants with a rough upper surface and 6 custom-made implants with a smooth machined upper surface were placed subcrestally with the upper surface facing up in the femurs of 6 adult male rats. Five rats were sacrificed 7 days after the implant placement, and the periosteum above the embedded implant was obtained and analyzed by quantitative real-time RT-PCR for the target genes: alkaline phosphatase (ALP), bone sialoprotein (BSP) and osteocalcin (OCN). The other rat was sacrificed at day 7, and both implants and the surrounding tissue were embedded in paraffin. For light microscopic observations, paraffin sections were stained with toluidine blue. Gene expression of ALP, BSP and OCN at the rough surface implant was significantly higher than that at the smooth machined surface implant. At day 7, both types of implant were covered with soft tissue, but a lower number of cells stained with toluidine blue was observed on the machined surface compared with on the rough surface. It is considered that rough surfaces may stimulate osteoblasts, and that ALP activity is increased indirectly. Furthermore, the two other markers were also increased by the rough surface in vivo, and different distributions of cellular and extracellular components on the upper surface of the implants were observed at day 7. These results suggest that a rough surface implant under the periosteum promotes higher gene expression of ALP, BSP and OCN in rat.

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The human dental caries pathogen Streptococcus mutans harbors one glucan-binding wall-anchored protein gene, gbpC, and another human pathogen, Streptococcus sobrinus, has 4 gbpC homologues. As no 4 gbpC homologues have so far been detected in other mutans streptococci, however, we cannot say whether those in S. sobrinus are paralogous or orthologous. Therefore, the purpose of this study was to identify and sequence the gbpC/dbl genes in Streptococcus downei and Streptococcus criceti. The findings revealed that the former harbored 5 gbpC/dbl homologues and the latter 4. In addition, another dbl homologue, the dblC gene, was found in some strains of S. sobrinus. We performed a phylogenetic analysis with the gbpC/dbl genes in these mutans streptococci. These results indicate that the gbpC and dbl genes have an orthologous relationship.

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In economics, the concept of utility refers to the strength of customer preference. In health care assessment, the visual analogue scale (VAS), the standard gamble, and the time trade-off are used to measure health state utilities. These utility measurements play a key role in promoting shared decision-making in dental care. Individual preference, however, is complex and dynamic. The purpose of this study was to investigate the relationship between patient preference and educational intervention in the field of dental health. The data were collected by distributing questionnaires to employees of two companies in Japan. Participants were aged 18-65 years and consisted of 111 males and 93 females (204 in total). One company (Group A) had a dental program of annual check-ups and health education in the workplace, while the other company (Group B) had no such program. Statistical analyses were performed with the t-test and Chi-square test. The questionnaire items were designed to determine: (1) oral health-related quality of life, (2) dental health state utilities (using VAS), and (3) time trade-off for regular dental check-ups. The percentage of respondents in both groups who were satisfied with chewing function, appearance of teeth, and social function ranged from 23.1 to 42.4%. There were no significant differences between groups A and B in the VAS of decayed, filled, and missing teeth. The VAS of gum bleeding was 42.8 in Group A and 51.3 in Group B (p<0.05). The percentage of persons having a regular dental check-up every three months was 34.1 and 31.3% in Groups A and B respectively. These results suggest that low preference results from lack of opportunity or utilization of dental care in the worksite. Ascertaining the factors involved in patient preference may have significant potential benefits in shared decision-making.

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With the founding of its Oral Cancer Center at the Ichikawa General Hospital, Tokyo Dental College established a support system for patients and family members that not only provides surgery and other conventional cancer-oriented treatments, but also palliative care, nutritional support, rehabilitation, and discharge support. With this in mind, the present study sought to examine the nature of support for oral cancer patients with postoperative eating and swallowing disorders by investigating these disorders and identifying their risk factors. The study population comprised 75 surviving oral cancer patients (46 men and 29 women) discharged from the Tokyo Dental College Oral Cancer Center following treatment over a 2-year period from April 2009 to March 2011. Risk factors affecting eating and swallowing function were identified by statistical analysis. Mean age of the patients was 67.3±13.7 years. Fifteen patients had stage I cancer, while 25 had stage II, 13 had stage III, and 22 had stage IV. The feeding route at the time of discharge was oral feeding in 74 patients and a combination of oral and gastrostomy tube feeding in 1 patient. The Tokyo Dental College Ichikawa General Hospital has standardized the expert evaluation and rehabilitation of oral cancer patients with eating and swallowing disorders by establishing a multidisciplinary support system from the preoperative stage onwards. In this context, the results of our analysis of factors influencing the ability of oral cancer patients to orally ingest food after treatment suggest that preoperative cancer stage classification, neck dissection, and tracheotomy are all influential factors. Patients affected by these factors require further multidisciplinary treatment, which in turn necessitates more extensive coordination with other medical professionals and community health care providers.

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Sotos syndrome is inherited in an autosomal-dominant manner and is characterized by increased birth weight, excessive growth, advanced bone age, and distinctive facial features, including dolichocephaly, hypertelorism, and a prominent mandible. We treated a jaw deformity due to Sotos syndrome consisting of malocclusion due to a narrow maxillary dental arch and mandibular retrusion from hypoplasia of the rami. The patient was a 17-year-old man. Malocclusion due to a narrow maxillary dental arch and mandibular retrusion was diagnosed. Rapid maxillary expansion with Lines corticotomy and mandibular advancement with distraction osteogenesis were performed. The maxilla was expanded laterally a total of 3 mm and the mandible prolonged 12 mm in the posterior area of the mandibular body. Subsequently, orthodontic treatment was continued. At present, 5 years after surgery, occlusion remains good and stable.

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Two patients requiring surgical management for leakage of calcium hydroxide paste from a root canal into the infraorbital space are reported. A paste root canal treatment material used at the time of maxillary root canal treatment had leaked out of the root canal in both patients. Computed tomography confirmed displacement of the root canal treatment material into the soft tissue, with extension into the infraorbital space. In both cases, foreign body removal was performed. Root canal treatment using a calcium hydroxide paste should be performed carefully without strong pressure.

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In this case report, we describe the clinical course over a 14-year follow-up in a 47-year-old diabetes patient with severe chronic periodontitis and nifedipine-induced gingival overgrowth. The patient had a history of hypertension for over 5 years and uncontrolled type 2 diabetes. Overgrown gingiva was observed in most of the teeth and was marked in the upper and lower anterior teeth. A probing pocket depth of ≥4 mm and bleeding on probing (BOP) were observed in 94 and 90% of sites examined, respectively. At baseline, his hemoglobin A1c (HbA1c) was 8.5%. The patient received periodontal and diabetic treatment simultaneously. Medication was changed from nifedipine chloride to an angiotensin-converting enzyme inhibitor. After initial therapy and subsequent periodontal surgery, gingival overgrowth disappeared and probing depth and BOP showed a significant improvement. No recurrence was observed during supportive periodontal therapy (SPT). The HbA1c level improved from 8.5 to 6.3% after periodontal treatment, subsequently remaining at a good level during SPT over 10 years. This study demonstrated that periodontal treatment, withdrawal of medication and control of diabetes can result in remarkable improvements in type 2 diabetes patients with chronic periodontitis and nifedipine-induced gingival overgrowth. These results suggest that comprehensive periodontal treatment in combination with treatment for diabetes mellitus can exert a positive influence on blood glucose levels and periodontal condition in diabetic patients.

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