The number of microvascular complications is associated with an increased risk for severity of periodontitis in type 2 diabetes patients: Results of a multicenter hospital-based cross-sectional study

Aims/Introduction

To explore the relationships between periodontitis and microvascular complications as well as glycemic control in type 2 diabetes patients.

Materials and Methods

This multicenter, hospital‐based, cross‐sectional study included 620 patients with type 2 diabetes. We compared the prevalence and severity of periodontitis between patients with ≥1 microvascular complication and those without microvascular complications. We also compared the prevalence and severity of periodontitis among patients with different degrees of glycemic control.

Results

After adjusting for confounding factors, multiple logistic regression analysis showed that the severity of periodontitis was significantly associated with the number of microvascular complications (odds ratio 1.3, 95% confidence interval 1.1–1.6), glycated hemoglobin ≥8.0% (64 mmol/mol; odds ratio 1.6; 95% confidence interval 1.1–2.3), and older age (≥50 years; odds ratio 1.7; 95% confidence interval 1.1–2.6). However, the prevalence of periodontitis was not significantly associated with the number of microvascular complications, but was associated with male sex, high glycated hemoglobin (≥8.0% [64 mmol/mol]), older age (≥40 years), longer duration of diabetes (≥15 years) and fewer teeth (≤25). Furthermore, propensity score matching for age, sex, diabetes duration and glycated hemoglobin showed that the incidence of severe periodontitis was significantly higher among patients with microvascular complications than among those without microvascular complications (P < 0.05).

Conclusions

The number of microvascular complications is a risk factor for more severe periodontitis in patients with type 2 diabetes, whereas poor glycemic control is a risk factor for increased prevalence and severity of periodontitis.

Evaluation of postextraction bleeding incidence to compare patients receiving and not receiving warfarin therapy: a cross-sectional, multicentre, observational study

OBJECTIVES

We investigated incidence and risk factors for postextraction bleeding in patients receiving warfarin and those not receiving anticoagulation therapy.

DESIGN

Cross-sectional, multicentre, observational study.

SETTING

26 hospitals where an oral surgeon is available.

PARTICIPANTS

Data on 2817 teeth (from 496 patients receiving warfarin, 2321 patients not receiving warfarin; mean age (SD): 62.2 (17.6)) extracted between 1 November 2008 and 31 March 2010, were collected. Warfarin-receiving patients were eligible when prothrombin time-international normalised ratio (PT-INR) measured within 7 days prior to the extraction was less than 3.0.

INTERVENTIONS

Simple dental extraction was performed, and incidence of postextraction bleeding and comorbidities were recorded.

PRIMARY AND SECONDARY OUTCOME MEASURES

Postextraction bleeding not controlled by basic haemostasis procedure was clinically significant.

RESULTS

Bleeding events were reported for 35 (7.1%) and 49 (2.1%) teeth, of which 18 (3.6%) and 9 (0.4%) teeth were considered clinically significant, in warfarin and non-warfarin groups, respectively, the difference between which was 3.24% (CI 1.58% to 4.90%). The incidence rates by patients were 2.77% and 0.39%, in warfarin and non-warfarin groups, respectively (incidence difference 2.38%, CI 0.65% to 4/10%). Univariate analyses showed that age (OR 0.197, p=0.001), PT-INR (OR 3.635, p=0.003), mandibular foramen conduction anaesthesia (OR 4.854, p=0.050) and formation of abnormal granulation tissue in extraction socket (OR 2.900, p=0.031) significantly correlate with bleeding incidence. Multivariate analysis revealed that age (OR 0.126, p=0.001), antiplatelet drugs (OR 0.100, p=0.049), PT-INR (OR 7.797, p=0.001) and history of acute inflammation at extraction site (OR 3.722, p=0.037) were significant risk factors for postextraction bleeding.

CONCLUSIONS

Our results suggest that there is slight but significant increase in the incidences of postextraction bleeding in patients receiving warfarin. Although absolute incidence was low in both groups, the bleeding risk is not negligible.

A toothbrush impalement injury of the floor of mouth in autism child

Penetrating injuries in the oral cavity are common in children. However, penetrating injuries with retained foreign bodies are rare. We report a case of a toothbrush impalement injury of the floor of the mouth in a child with autism. A 5-year-old boy with autism presented with an accidentally impaled toothbrush in the oral cavity. He was taken to the operation room and examined under general anesthesia. The handle of the toothbrush was cut off using rib scissors for mask ventilation, and intra-oral intubation was performed. The toothbrush was located approximately 2.5 cm into the floor of the mouth. The toothbrush was removed uneventfully. Intravenous antibiotic therapy was instituted during hospitalization, and discharge from the hospital occurred 4 days after the operation.

PLGA artificial nerve conduits with dental pulp cells promote facial nerve regeneration

A number of recent studies have shown the effectiveness of tubulation, using neural progenitor cells or Schwann cells, for promoting nerve regeneration. However, the use of neural cells from other neural donor tissues has potentially serious clinical complications. Therefore, we focused on dental pulp as a new cell source for use in such artificial conditions. Previously, we showed that silicone tubes filled with dental pulp cells (DPCs) promoted facial nerve regeneration in rats. However, the use of silicone tubes requires a secondary removal operation because they may give rise to chronic inflammation and pain. Therefore, to avoid this procedure, a new artificial device was prepared from a degradable poly-DL-lactide-co-glycolide (PLGA) tube containing DPCs, and its effectiveness for repairing gaps in the facial nerves of rats was investigated. A PLGA tube containing rat DPCs embedded in a collagen gel was transplanted into a gap in a rat facial nerve. Five days after transplantation, the facial nerves connected by the PLGA tubes containing DPCs were repaired more quickly than the control nerves. The PLGA tubes were resorbed in vivo and nerve regeneration was observed 2 months after the transplantation. Immunostaining showed that Tuj1-positive axons were present in the regenerated nerves 2 months after transplantation, and osmium-toluidine blue staining showed no mineralization of the regenerated nerves in those tubes containing myelinated fibres after 9 weeks. PLGA tubes filled with DPCs promoted nerve regeneration and were readily resorbed in vivo.

A protocol for immunofluorescence staining of floating neurospheres

This protocol describes the immunofluorescence staining of floating neurospheres in culture plates. Although this protocol is similar to conventional immunofluorescence staining, the staining procedure of floating neurospheres in multiwell culture plates and the washing procedure are different. Neurospheres in culture plates are transferred to a 12-well plate using a 200-1000microL pipette. The spheres are precipitated by gravity for 3min. Then, the 12-well plate is tilted slightly, and the culture medium is aspirated by the pipette. After aspiration, the spheres are visually verified to be at the bottom of the wells. PBS (400microL) is added to the well for washing the spheres. This procedure is repeated three times. This protocol is easier than a conventional procedure using cryostat sections and can give clear sphere structures.

Tubulation with dental pulp cells promotes facial nerve regeneration in rats

Dental pulp is an easily obtainable source of viable cells for potential use in peripheral nerve regeneration. We prepared artificial conditions for nerve regeneration using a silicone tube containing a collagen gel embedded with rat dental pulp cells, and we examined its effectiveness for repairing a gap in the rat facial nerve. Twelve days after transplantation, defective facial nerves connected with silicone tubes containing dental pulp cells were repaired more rapidly than control tubes containing the collagen gel alone. When a tube containing green fluorescent protein (GFP)-positive dental pulp cells was transplanted into a facial nerve gap in a GFP-negative rat, we observed regenerated nerves with GFP-positive cells at 2 weeks posttransplantation. The regenerated nerves included Tuj1-positive axons, RECA1 and GFP double-positive blood vessels, and S100 and GFP double-positive Schwann-like supportive cells. Osmium-toluidine blue staining revealed that the regenerated nerves contained myelinated fibers. Moreover, fluorescent retrograde tracing analysis by application of Fluoro-Gold into the regenerated nerves demonstrated the presence of Fluoro-Gold-positive motor neurons in the facial nucleus of the rat brain. These results suggest that the transplanted dental pulp cells formed blood vessels and myelinating tissue and contributed to the promotion of normal nerve regeneration.

Thymidylate synthase, thymidine phosphorylase and orotate phosphoribosyl transferase levels as predictive factors of chemotherapy in oral squamous cell carcinoma

We conducted a clinicopathologic study on protein and mRNA levels of thymidylate synthase (TS), thymidine phosphorylase (TP) and orotate phosphoribosyl transferase (OPRT) using biopsy tissue specimens before treatment. The mRNA levels have been measured in tumor cells microdissected from paraffin-embedded specimens (Danenberg Tumor Profile method: DTP method). We studied the mRNA and protein expression as effect predictive factors in chemotherapy. The subjects consisted of 20 cases of untreated oral squamous cell carcinoma who had undergone chemotherapy with TS-1 (16 males and 4 females, tongue in 8 cases, upper gingiva in 3 cases, lower gingiva in 3 cases, buccal mucosa in 5 cases and floor of the mouth in 1 case). TS gene expressions of the responders were lower than those for the nonresponders. Furthermore, regarding males who were less than 70 years of age, stage I and II, well differentiated type and tongue, TS mRNA expression of the responders were lower than that for the nonresponders. The mRNA expression of OPRT for the male responders was lower than that for the nonresponders. No remarkable difference was observed by immunohistochemistry. In this study, the measurement of the TS levels using the DTP method may potentially act as a predictive factor of antitumor effectiveness.

Possible involvement of T cell co-stimulation in pustulosis palmaris et plantaris via the induction of inducible co-stimulator in chronic focal infections

BACKGROUND

Inducible co-stimulator (ICOS) is a co-stimulatory receptor on activated T cells that provides the signals needed for Th1 and Th2 responses via its interaction with B7h. Chronic focal infections are closely related to pustulosis palmaris et plantaris (PPP), but the involvement of ICOS in PPP has not been clarified.

OBJECTIVE

To investigate the effectiveness of treatments for focal infections on PPP skin lesions and the involvement of ICOS-positive T cells at focal infection sites in the tonsils and in PPP lesional skin.

METHODS

In patients that had undergone a tonsillectomy or dental treatment, the clinical activities of PPP, both the skin lesions and pustulotic arthro-osteitis were followed for over 2 years. The expressions of ICOS and various other activation markers on T cells were examined in tonsil tissue from both PPP patients and non-PPP patients, and the expression levels in peripheral blood were also evaluated in PPP patients and healthy donors. ICOS-positive T cells and B7h expression in PPP and normal skin were examined immunohistochemically.

RESULTS

The above treatments for focal infections led to a dramatic and persistent improvement in the PPP skin lesions and pustulotic arthro-osteitis. The expression of ICOS, but not of other activation markers, was higher in tonsil tissues from PPP patients than in tonsil tissues from non-PPP patients. B7h was upregulated without numerous ICOS-positive T cell infiltrates in the skin lesions.

CONCLUSION

The activation of T cells via ICOS co-stimulation in focal infections likely triggers the skin and skeletal inflammation associated with PPP, resulting in tissue damage.

Claudin rather than occludin is essential for differentiation in rat incisor odontoblasts

Many morphological and developmental studies have demonstrated the characteristics of tight junctions (TJs) between odontoblasts. However, detailed localization of TJ-associated proteins in odontoblasts and their functions has not yet been clarified. To elucidate the relationship between the establishment of TJ structures and the differentiation of odontoblasts during early dentinogenesis, we studied the expression and localization of constituent proteins of TJs (claudin-1, occludin, ZO-1 and ZO-2) between odontoblasts in rat lower incisors using Western blotting, immunofluorescence and immunoelectron microscopy. When the expression of claudin-1 increases at the distal portion of mature odontoblasts, the TJs form complex networks of strands, and odontoblasts differentiated by developing distal membrane domains and by secreting specific molecules for mineralization. We conclude that the TJs of odontoblasts may play an important role in the differentiation of odontoblasts in rat lower incisors during early dentinogenesis.

[Nedaplatin (NDP)-combination therapy (NDP/5-FU,NDP/S-1) for oral cancer]

PURPOSE

The present study evaluated the efficacy and safety of nedaplatin-combination therapy (NDP/5-FU [5-FU arm] or NDP/S-1 [S-1 arm] ) for the treatment of oral squamous cell carcinoma.

PATIENTS AND METHOD

Previously non-treated oral squamous cell carcinoma patients were eligible. Patients received 5-FU 600 mg/m(2)iv, as a 24-hour infusion (day 1 to 5) followed by NDP 80 to 100 mg/m(2) iv (day 1), or S-1 60 to 80 mg/m(2) orally twice a day (day 1 to 14) followed by NDP 80 mg/m(2) iv (day 8) every 28 days for one or two cycles.

RESULTS

In total, 32 patients (18 in the 5-FU arm, 14 in the S-1 arm) were enrolled. Twenty patients were male and 12 were female. Median age was 57 years (range 20 years to 87 years). Thirty-one patients had a performance status (PS) oF 0, and 1 patient had a PS 1. Three patients were stage I, 12 stage III, and 12 were stage IV. The overall response rate was 69% (5-FU arm,72%;S-1 arm,64%). Two patients achieved a complete response, 20 patients a partial response, and 10 patients had no change. Grade 3 leucopenia, grade 3 and 4 thrombocytopenia and liver injury occurred in 6% (one in the 5-FU arm, and one in the S-1 arm), 9% (two in the 5-FU arm, and one in the S-1 arm), and 3% (one in the 5-FU arm), respectively. No other severe toxicities were observed.

RESULTS

Response rate and toxicities were similar in both arms. However, the psychosocial stress on patients in the S-1 arm was reduced compared to that in the 5-FU arm, which required hospitalization for a longer period. The outcome in the present study needs further investigation.

CD28 is required for induction and maintenance of immunological memory in toxin-reactive CD4+ T cells in vivo

We previously reported that Vbeta3+ CD4+ T cells maintained a protracted expansion, with the phenotypes of memory Th2 cells, for 30 days in C57BL/6 (B6) mice implanted with SEA-containing mini-osmotic pumps. In the present study, we followed the fate of Vbeta3+ CD4+ T cells in CD28-/- mice. Vbeta3+ CD4+ T cells increased to a degree similar to that of B6 Vbeta3+ CD4+ T cells until day 10 after implantation, then declined rapidly reaching the control level by 28 days. Remaining Vbeta3+ CD4+ T cells at that time did not exhibit memory phenotypes nor Th2-deviated responses. The rapid drop in Vbeta3+ CD4+ T cells in CD28-/- mice was attributable to upregulated induction of apoptosis owing to marginal inductions of Bcl-2 and Bcl-xL. Collectively, these data indicate CD28 to play critical roles in the generation and maintenance of SEA-reactive CD4+ T cells in vivo.

Expression and function of the co-stimulator H4/ICOS on activated T cells of patients with rheumatoid arthritis

OBJECTIVE

To investigate the expression and function of the inducible co-stimulator H4/ICOS in rheumatoid arthritis (RA) patients. H4/ICOS is the newest member of the CD28/CTLA-4 family to have been found to be expressed on activated T cells, and it participates in a variety of important immunoregulatory functions.

METHODS

The levels of H4/ICOS expression on T cells among peripheral blood mononuclear cells (PBMC) and synovial fluid mononuclear cells (SFMC) from 28 patients with RA were analyzed by flow cytometry. To explore the role of H4/ICOS function in the inflammation of rheumatoid joints, lymphokine production by SF CD4+ T cells co-stimulated by H4/ICOS was assayed. Expression of H4/ICOS ligand (B7RP-1) mRNA in synovial tissues from patients with RA was examined by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

H4/ICOS-positive cells were increased significantly in whole, CD4+, and CD8+ T-cell fractions of SFMC compared with control PBMC. Comparison between control PB and PB from patients with active RA showed that H4/ICOS-positive whole and CD8+ T-cell fractions were increased significantly in the PB of RA patients. H4/ICOS costimulation clearly increased interferon-g, interleukin 4 (IL-4), and IL-10 production by SF CD4+ T cells. By RT-PCR, RA synovial tissue was shown to express mRNA of B7RP-1.

CONCLUSION

Our results suggest that local immune responses may be modulated by H4/ICOS expressed on T cells in the joints of patients with RA, and thus H4/ICOS may be involved in the pathogenetic mechanism of RA.

[Diagnosis of the autonomic nervous function during sedation by peripheral blood flow and psychogenic perspiration]

BACKGROUND

Pain induces a variety of physiological responses, many of which are mediated by the sympathetic nervous system. Among these are a reduction in peripheral blood flow and evaporative cutaneous water loss (sweating). We therefore tested the hypothesis that adequate sedation obliterates the normal pain-induced reduction in peripheral blood flow and an increase in evaporative water loss.

METHODS

We studied eight volunteers. Two different painful stimuli were randomly applied: 1) electrical pulp stimulation (200 microamperes) and 2) electrical pain stimulation on the right upper thigh (80 mA). Conscious sedating was controlled by propofol infusion titrated to a Bispectral Index near 80, or near 60.

RESULTS

At each stimulation, peripheral blood flow detected by laser Doppler decreased without any relation to the level of consciousness (by Bispectral Index). On the other hand, although the psychogenic perspiration rate increased significantly at alert level, during BIS 80 or 60 level, the increase was not significant.

CONCLUSION

Peripheral blood flow reacts most to pain stimulation during intravenous sedation.

Gastrointestinal diseases and halitosis: association of gastric Helicobacter pylori infection

The relationship between gastrointestinal conditions and halitosis is discussed. Few reports have suggested that gastrointestinal diseases may cause halitosis. H. pylori infection, which causes gastric ulcers, is considered as a possible cause for halitosis. Intensity of malodour of mouth air was found to be higher in H. pylori-positive patients than in negative patients. The levels of hydrogen sulphide and dimethyl sulphide in mouth air were also significantly higher in the positive patients than in the negative patients (P<0.05). When odour strength in exhaled breath was compared between the two groups, no significant difference was found. Hence, H. pylori infection might not cause a systemic condition producing breath odour. Although there were no significant differences in periodontal parameters or tongue coating between the positive and negative groups, H. pylori may be a frequent contributor to the production of malodour even though its role had not been suspected before. Further study would be necessary to clarify the reason for the increase of volatile sulphur compounds (VSCs) level in H. pylori infection.

[Combination chemotherapy with nedaplatin (CDGP) and 5-FU for oral cancer]

Chemotherapy using CDGP plus 5-FU was evaluated in patients with oral cancer. The subjects were patients with squamous cell carcinoma of the oral cavity who had not received any therapy, comprising 7 patients with carcinoma of the tongue, 2 with buccal carcinoma, 2 with maxillary gingival carcinoma, and 1 with carcinoma of the oral floor. There were 4 patients in Stage II, 3 patients in Stage III and 5 patients in Stage IV. Patients with a PS < or = 1, WBC > or = 4,000/mm3, Hb > or = 10 g/dl, platelet count > or = 10 x 10/mm3, and normal liver, kidney, and heart function at baseline were selected for this study. In all patients, 5-FU was administered at a dose of 600 mg/m2/day for 5 days (day 1 to day 5) by continuous infusion, for a total dose of 3,000 mg/m2. CDGP was administered on day 1 at a dose of 80 mg/m2 in 8 patients and at 100 mg/m2 in 4 patients. This treatment was one course of therapy, and patients received 1 or 2 courses. Of 12 patients who were evaluable, there were 9 partial responses and 3 no changes, for a major response rate of 75%. Toxicities experienced by patients were mild (grade 2 or lower) gastrointestinal disorders (including nausea/vomiting) and renal impairment, while grade 3 leukopenia and thrombocytopenia developed in 1 patient each and grade 4 thrombocytopenia occurred in another patient. Thus, patients receiving CDGP + 5-FU therapy should be closely monitored for hematologic toxicity. Since CDGP + 5-FU therapy achieved a good response rate (75%) in the treatment of squamous cell carcinoma of the oral cavity, we plan to use this therapy in the future and assess its benefit in a larger number of patients.

Relationships between the onset of pustulosis palmaris et plantaris, periodontitis and bacterial heat shock proteins

Relationships between the onset of pustulosis palmaris et plantaris, periodontitis and heat shock proteins were studied by using enzyme-linked immunosorbent assay to examine levels of immunoglobulin G (IgG) against Escherichia coli GroEL, a recombinant DnaJ of Actinobacillus actinomycetemcomitans heat shock protein, a synthetic peptide made from the 180th to the 188th amino acids of Mycobacterium bovis BCG Hsp65, and a recombinant human Hsp60, in sera obtained from 43 pustulosis palmaris et plantaris patients judged to have chronic infectious diseases of the oral cavity. We found that the titers of IgG against E. coli GroEL and A. actinomycetemcomitans DnaJ in the sera from pustulosis palmaris et plantaris patients were significantly higher than those in the control group, whereas the titers of IgG against the synthetic M. bovis Hsp65 and the recombinant Hsp60 did not differ significantly. Periodontal therapy and extraction of teeth with periapical infectious resulted in remission of pustulosis palmaris et plantaris and a statistically significant reduction in the levels of IgG against E. coli GroEL in 9 of the 22 patients (41%) examined. We also found that the IgG levels against A. actinomycetemcomitans DnaJ in 6 serum samples of 16 (37%) were reduced, but not significantly, after the treatment. These results suggest that the IgG responses to heat shock proteins partially induced by oral bacteria may be related to the onset of pustulosis palmaris et plantaris in some patients.

A decrease in seizure susceptibility to lidocaine in kindled epileptic rats

Lidocaine induces electroencephalographic seizures and generalized convulsions at large doses. It is possible that epileptic patients are more susceptible to the proconvulsant effect of lidocaine. Using a kindling model of epilepsy, we examined whether the seizure susceptibility to lidocaine increases in epileptic rats. Kindled epileptic rats were prepared by repeated, initially subconvulsive, electrical stimulations applied to the amygdala for 9-14 days through a chronically implanted electrode, resulting in the establishment of a long-lasting epileptic focus. Unexpectedly, kindled rats had significantly less susceptibility to the proconvulsant action of IV lidocaine. Lidocaine-induced convulsions were observed in 11%, 75%, and 77% of control rats at 7.5, 10.0, and 12.5 mg/kg, respectively, compared with 0%, 25%, and 37% of amygdala-kindled rats, respectively. We also demonstrated that small doses of lidocaine suppressed kindled seizures in a dose-dependent manner. We conclude that the critical mechanisms underlying lidocaine-induced seizures differ from the mechanisms underlying kindled epileptogenesis. Furthermore, the establishment of a kindled epileptic focus decreases susceptibility to the proconvulsant action of lidocaine.

Cell proliferation and death of Hertwig's epithelial root sheath in the rat

Hertwig's epithelial root sheath (HERS) degenerates immediately after root dentin is formed. However, odontogenic tumors or cysts may originate from residual cells, although little is known about how HERS proliferates and disappears. This study investigated whether cell death is provoked in the tissues surrounding the root during eruption of the rat upper molar. We employed the TdT-mediated-dUTP nick end labeling (TUNEL) method and transmission electron microscopy (TEM) to observe the morphological features of cell death. We examined the activity of cell proliferation immunohistochemically using proliferative cell nuclear antigen (PCNA) and the continuity of HERS using polyclonal keratin antibody (PK). Cell death resembling apoptosis and apoptotic bodies phagocytosed by neighboring mesenchymal cells were detected in only a few cells by both TUNEL and TEM. We also found cells with electron-lucent cytoplasm which contained dilated or ruptured mitochondria and remarkably dilated rough endoplasmic reticulum (rER) which lay sparsely along the root. These cells seemed to be dead HERS cells based on their ultrastructural features, location, and stage. PCNA-positive cells were found in the apical end of the HERS cells, fibroblasts of the periodontal ligament, and odontoblasts. PK reacted with HERS; however, PK-positive cells partially disappeared after the 15th postnatal day when the root dentin had formed slightly. These results may indicate that HERS cells migrate into the periodontal ligament or die immediately after root dentin is formed and that various types of cell death such as apoptosis and cytoplasmic type occur in the tissues surrounding the root during tooth development.

Cell death during tooth eruption in the rat: surrounding tissues of the crown

We investigated the occurrence of apoptosis and other types of cell death around the crown during tooth eruption of the rat upper molar. The TdT-mediated-dUTP-biotin nick end labeling (TUNEL) method and transmission electron microscopy (TEM) were employed. Apoptosis was detected by both TUNEL and TEM in part of the reduced enamel epithelium and connective tissue in the resorbing bony crypt of the pre-erupted tooth. In TEM, a large number of cells showed condensed chromatin and membrane-bound small bodies (apoptotic bodies). Macrophages that phagocytosed apoptotic bodies could be detected. Based upon the distance between bone surface and these apoptotic cells, and the characteristics of their organelles, we suggested that the apoptotic cells might be osteocytes, bone-lining cells (osteoblasts), and macrophages. We surmised that the osteoclasts had also died. Cells which contained autophagic vacuoles and autophagosomes, and others whose cytoplasm had dissolved, were also frequently observed. No progressive cell death was found in the oral epithelium or the fibrous connective tissue over the crown. These results suggest that apoptosis gives rise to some cell death during tooth eruption, but that other types of cell death also occur in various cells.

Heat shock proteins in the human periodontal disease process

The production of HSP by periodontopathic Gram-negative bacteria was examined by SDS-PAGE, two dimensional gel electrophoresis, and Western blotting using monoclonal antibodies against HSPs. Strains of Actinobacillus actinomycetemcomitans, Eikenella corrodens, Fusobacterium nucleatum, Prevotella intermedia, Prevotella nigrescens, Prevotella melaninogenica, and Treponema socranskii species produced HSP which reacted with anti-Yersinia enterocolitica HSP 60 and/or mycobacterial 65-kDA HSP monoclonal antibodies. It found that gingival homogenate samples from patients with adult periodontitis reacted with anti-human HSP were also found in a serum sample from a periodontitis patient. The present study suggests that HSPs are implicated in human periodontal disease process.

Case report of lateral crossbite. Part I. Mixed dentition

Lateral crossbite on mixed dentition does not always cause facial asymmetry or functionally abnormal movement of the mandible in children. However, it is often observed that facial asymmetry will worsen during growth in the absence of orthodontic treatment. In adult cases, lateral crossbite is one of the etiological factors of temporomandibular joint disorder. This case report presents two cases of lateral crossbite of mixed dentition. The terms of treatment were shorter than those in cases with permanent dentition. Also, methods of treatment were simpler, and the patients developed favorably. The opposite results were obtained in cases of permanent dentition.

Histopathological observation of dense particulate hydroxyapatite consolidated in the frontal sinus of dogs

Dense particles of hydroxyapatite (HAP) were consolidated in the frontal sinus of dogs, and bone formation with time was observed in undecalcified ground sections using Cole's HE stain. In the HAP mass on the experimental side, a small amount of newly generated bone was seen around the inner wall of the sinus after 3 months. Even after 12 months, bone formation was still limited to the surrounding region and did not extend to the central region of the sinus. In the sinus opened area, bone formation was seen from both ends of the bone along the HAP particles, and ossiferous closing was observed without leaving a recess at 12 months. On the control side, yellow bone marrow tissue, pneumatic spaces or cyst formation were seen, and a recess was left in the sinus opened area in all cases.

A comparative study of the JJC, AJC and UICC T classifications of squamous cell carcinoma of the maxillary sinus

Seventy-six cases with squamous cell carcinoma of the maxillary sinus were treated with radiotherapy and surgery with or without intra arterial infusion between 1969 to 1985 at the Tokyo Women's Medical College. T classification was made of all cases using the Japan Joint Committee (JJC, 1967), American Joint Committee (AJC, 1977) and Union Internationale Contre le Cancer (UICC, 1987) classifications. 1) By the JJC classification, there were 20 cases in T2, 44 in T3 and 12 in T4. By the AJC classification, there were 9 cases in T2, 58 in T3 and 9 in T4. The classification of 14 cases were changed from JJC T2 to AJC T3, because of extension to the medial nasal meatus. By the UICC classification, there were 27 T2 cases, 32 T3 and 17 T4. 2) Cervical lymph node metastasis was detected in 14 cases (18%) at initial diagnosis and most were found in T3 and T4 cases. 3) The cumulative 5-year survival rates were 67% for T2, 32% for T3 and 25% for T4 by the JJC classification and statistical differences (p less than 0.05) were seen in T2-T3 and T2-T4. In the AJC classification, these were 71% for T2, 37% for T3 and 22% for T4 and no statistical significance was found among them. By the UICC classification, the 5-year survival was 58% for T2, 26% for T3 and 38% for T4 and marked statistical significance (p less than 0.01) was seen in T2-T3 and T2-T4. 4) The cumulative 5-year survival rate in 14 patients with tumor extension to the medial nasal meatus was 55% and it is appropriate to define this stage as T2 in the new UICC classification. These data suggested that UICC classification (1987) is useful and correlated with prognostic analysis.

Oro-maxillofacial development in patients with GH deficiency and in normal short children

Detailed oro-maxillofacial studies using dental cast, pantomogram and cephalogram were performed in 43 patients with GH deficiency aged 7-17 years and compared statistically to the results from 62 short children with normal GH secretion. The dental age was retarded as compared to the chronological age in patients with GH deficiency by a mean of 2.0 +/- 1.3 years. This value did not differ statistically from that observed in normal short children (1.7 +/- 0.8 years). However the bone age was significantly retarded in patients with GH deficiency (3.2 +/- 1.7 yrs vs 1.5 +/- 1.1 yrs, p less than 0.001). There was no difference between tooth size or cephalogram analysis results in the children in the two groups. The coronal arch length, basal arch width and basal arch length were shorter in patients with GH deficiency. These data indicate underdevelopment of the maxilla in patients with GH deficiency.

Oro-maxillofacial development in patients with Turner's syndrome

Detailed oro-maxillofacial studies using dental casts, pantomograms and cephalograms were performed in 28 patients with Turner's syndrome and compared statistically to the results from 23 normal short children. Small tooth crown size, short tooth roots and advanced dental age were characteristic of patients with Turner's syndrome. However, the incidence of peg shaped teeth, malocclusion, high arched palate and congenital anodontia were not characteristic of patients with Turner's syndrome. The coronal arch width (C.A.W.) and basal arch width (B.A.W.) were greater and the coronal arch length (C.A.L.) and basal arch length (B.A.L.) were less in patient's with Turner's syndrome. These data indicate underdevelopment of the maxilla in the forward direction forming the wide-, flat-shaped facial characteristic of patients with Turner's syndrome.