Degree Of Alveolar Bone Loss Research Articles

Effects of epigallocatechin-3-gallate on oxidative stress, inflammation, and bone loss in a rat periodontitis model

Background/purposeEpigallocatechin-3-gallate (EGCG) is playing an increasingly important role in the treatment of oral diseases. However, its mechanisms remain to be clarified. This study aimed to investigate the effect of EGCG on oxidative and inflammatory stress and bone loss in experimental periodontitis. Materials and methodsPeriodontitis was induced in rats, followed by gavage using different concentrations of EGCG for 5 weeks. The levels of interleukin-1β (IL-1β), interleukin-18 (IL-18), tumor necrosis factor-α (TNF-α), superoxide dismutase (SOD) and malondialdehyde (MDA) in rats were measured. The degree of alveolar bone loss and the number of inflammatory cells were detected. The integrated optical density of nuclear factor erythroid 2-related factor (Nrf2), heme oxygenase-1 (HO-1), NLR pyrin domain-containing 3 (NLRP3) and nuclear factor-kappaB p65 (NF-κB p65) was measured. ResultsEGCG (200 mg/kg) significantly reduced alveolar bone loss in the ligated maxillary molars and the number of inflammatory cells in the EGCG-200 group compared with the periodontitis, EGCG-100 and EGCG-400 groups. 200 mg/kg was the optimal dose of EGCG and was used in subsequent experiments. The expression levels of IL-1β, IL-18, TNF-α and MDA were significantly lower and the expression level of SOD was significantly higher in the EGCG-200 group compared with the periodontitis group. The expression of NLRP3 and NF-κB p65 was significantly decreased, while the expression of Nrf2 and HO-1 was significantly increased in the EGCG-200 group compared with the periodontitis group. ConclusionThese results suggest that EGCG inhibits oxidative stress and inflammatory responses in the periodontitis model by modulating the Nrf2/HO-1/NLRP3/NF-κB p65 signaling pathway, thereby decreasing alveolar bone loss.

A murine periodontitis model using coaggregation between human pathogens and a predominant mouse oral commensal bacterium.

PurposeC57BL/6 mice, which are among the most common backgrounds for genetically engineered mice, are resistant to the induction of periodontitis by oral infection with periodontal pathogens. This study aimed to develop a periodontitis model in C57BL/6 mice using coaggregation between human pathogens and the mouse oral commensal Streptococcus danieliae (Sd).MethodsThe abilities of Porphyromonas gingivalis ATCC 33277 (Pg33277), P. gingivalis ATCC 49417 (Pg49417), P. gingivalis KUMC-P4 (PgP4), Fusobacterium nucleatum subsp. nucleatum ATCC 25586 (Fnn), and F. nucleatum subsp. animalis KCOM 1280 (Fna) to coaggregate with Sd were tested by a sedimentation assay. The Sd-noncoaggregating Pg33277 and 2 Sd-coaggregating strains, PgP4 and Fna, were chosen for animal experiments. Eighty C57BL/6 mice received oral gavage with Sd once and subsequently received vehicle alone (sham), Fna, Pg33277, PgP4, or Fna+PgP4 6 times at 2-day intervals. Mice were evaluated at 5 or 8 weeks after the first gavage of human strains.ResultsFnn, Fna, and PgP4 efficiently coaggregated with Sd, but Pg33277 and Pg49417 did not. Alveolar bone loss was significantly higher in the PgP4 group at both time points (weeks 5 and 8) and in all experimental groups at week 8 compared with the sham group. The PgP4 group presented greater alveolar bone loss than the other experimental groups at both time points. A higher degree of alveolar bone loss accompanied higher bacterial loads in the oral cavity, the invasion of not only PgP4 but also Sd and Fna, and the serum antibody responses to these bacteria.ConclusionsPeriodontitis was successfully induced in C57BL/6 mice by oral infection with a P. gingivalis strain that persists in the oral cavity through coaggregation with a mouse oral commensal bacterium. This new model will be useful for studying the role of human oral bacteria-host interactions in periodontitis using genetically engineered mice.

Assessment of Alveolar Bone and Periodontal Status in Peritoneal Dialysis Patients.

Chronic kidney disease (CKD) affects 8–13% of the global population and has become one of the largest burdens on healthcare systems around the world. Peritoneal dialysis is one of the ultimate treatments for patients with severe CKD. Recently, increasing severe periodontal problems have been found in CKD patients. Periodontitis has been identified as a new variable risk factor for CKD. The aim of this study was to investigate the periodontal status and severity of alveolar bone loss in CKD patients with peritoneal dialysis (PD). One hundred and six patients undergoing PD (PD group) and 97 systemically healthy periodontitis patients (control group) were enrolled. The differences in the dimensions of the alveolar bone between two groups were compared, and the distribution of alveolar bone defects was analyzed by cone-beam computed tomography (CBCT). Gingival index (GI), plaque index (PLI), periodontal probing depth (PPD), and attachment loss (AL) were recorded. The levels of inflammatory factors in gingival crevicular fluid were assessed by ELISA. Compared to control group, there was a higher degree of alveolar bone loss in maxillary premolars, maxillary 2nd molar and mandibular 1st molar in patients with PD (p < 0.05). A comparison of bone loss in different sites revealed that the area with the highest degree of bone loss were on the mesial-buccal, mid-buccal, distal-buccal, and mesial-lingual site in PD patients. The expression levels of inflammatory factors were higher in PD group (p < 0.01). In conclusion, PD patients presented more severe periodontal and inflammatory status than systemically healthy periodontitis patients. The loss of the alveolar bone differed between the two groups. Different sites and teeth exhibited a diverse degree of bone loss. This study highlights that clinicians should pay close attention to periodontal status of peritoneal dialysis patients and provides a new thinking to improve healthcare for CKD.

Individualization of the three-piece base arch mechanics according to various periodontal support levels: A finite element analysis.

The orthodontic correction of periodontally compromised dentitions constitutes a huge challenge in the clinical practice of adult orthodontics. The biological and physical distinct features of these conditions require a carefully designed mechanical plan for the successful treatment of these complex cases. A segment of a human maxilla containing the central and lateral incisors, obtained from autopsy, was scanned with microcomputed tomography, and a finite element (FE) model was generated to represent an intact periodontal dentition. Based on this model, three additional models simulating a mild, moderate and severe bone alveolar loss were created as well. Two loading scenarios for the application of intrusive and retraction mechanics with a three-piece base arch appliance were evaluated in a series of FE analyses. The tooth displacements and strains in the periodontal ligament (PDL) were calculated and compared for the four FE models. The periodontal reduced dentitions exhibited a similar axis of resistance for intrusive mechanics, but the axis of resistance for retraction movements was significantly dependent on the degree of alveolar bone loss. The tooth displacements and PDL loads were higher in the reduced dentitions for both intrusive and retraction mechanics. A reduction in the force levels applied to periodontal reduced dentitions is indicated, and a customized selection of appropriate points of force application is needed according to the specific amount of alveolar bone loss.

Automatic methods for alveolar bone loss degree measurement in periodontitis periapical radiographs

Background and objectivePeriodontitis involves progressive loss of alveolar bone around the teeth. Hence, automatic alveolar bone loss measurement in periapical radiographs can assist dentists in diagnosing such disease. In this paper, we propose an automatic length-based alveolar bone loss measurement system with emphasis on a cementoenamel junction (CEJ) localization method: CEJ_LG. MethodThe bone loss measurement system first adopts the methods TSLS and ABLifBm, which we presented previously, to extract teeth contours and bone loss areas from periodontitis radiograph images. It then applies the proposed methods to locate the positions of CEJ, alveolar crest (ALC), and apex of tooth root (APEX), respectively. Finally the system computes the ratio of the distance between the positions of CEJ and ALC to the distance between the positions of CEJ and APEX as the degree of bone loss for that tooth. The method CEJ_LG first obtains the gradient of the tooth image then detects the border between the lower enamel and dentin (EDB) from the gradient image. Finally, the method identifies a point on the tooth contour that is horizontally closest to the EDB. ResultsExperimental results on 18 tooth images segmented from 12 periodontitis periapical radiographs, including 8 views of upper-jaw teeth and 10 views of lower-jaw teeth, show that 53% of the localized CEJs are within 3 pixels deviation (∼ 0.15 mm) from the positions marked by dentists and 90% have deviation less than 9 pixels (∼ 0.44 mm). For degree of alveolar bone loss, more than half of the measurements using our system have deviation less than 10% from the ground truth, and all measurements using our system are within 25% deviation from the ground truth. ConclusionOur results suggest that the proposed automatic system can effectively estimate degree of horizontal alveolar bone loss in periodontitis radiograph images. We believe that our proposed system, if implemented in routine clinical practice, can serve as a valuable tool for early and accurate diagnosis of alveolar bone loss in periodontal diseases and also for assessing the status of alveolar bone following various types of non surgical and surgical and regenerative therapy. For overall system improvement, a more objective comparison by using transgingival bone measurement with a periodontal probe as the ground truth and enhancing the localization algorithms of these three critical points are the two major tasks.

Assessment of Alveolar Bone Status in Middle Aged Chinese (40-59 Years) with Chronic Periodontitis--Using CBCT.

ObjectiveThis study used con-beam computed tomography (CBCT) to investigate the prevalence and severity of alveolar bone loss in middle-aged (40–59 years) Chinese with chronic periodontitis.Materials and MethodsThe study group comprised 145 dentate individuals aged 40 to 59 years residing in China who suffered from chronic periodontitis. CBCT and the application of NNT software were used to examine the level and location of alveolar bone loss.ResultsThe study revealed that 40–59 year old patients with chronic periodontitis had severe bone loss. At 5,286 sites (34.7%), alveolar bone loss was mild; severe alveolar bone loss was found at 5,978 sites (39.2%). A comparison of bone loss in different jaws revealed that the area with the highest degree of bone loss was on the lingual side of the maxillary molar (56.3 ± 7.2%), and that the area with the lowest degree was primarily on the lingual side of the mandibular canine (27.5 ± 6.3%). There was a lower degree of alveolar bone loss in males than females. Differences were observed when comparing the incidence of bone loss between males and females (P < 0.05). Menopause in females and smoking in both genders may affect the level of bone loss. Male smokers experienced a greater degree of bone loss (41.67 ± 5.76%) than male non-smokers (32.95 ± 4.31%). A 42.23 ± 6.34% bone loss was found in menopausal females versus 31.35 ± 3.62% in non-menopausal females.ConclusionsThe study revealed that different sites and teeth exhibited a diverse degree of bone loss. In middle-aged patients with chronic periodontitis, the highest degrees of bone loss in the incisors, premolars, and molars were on the lingual side, mesial side and lingual side, respectively. Menopause in females and smoking may affect the level of bone loss.

Evaluation of the relationship between periodontal risk and carotid artery calcifications on panoramic radiographs.

Objective:To evaluate if there is a relationship between findings of carotid artery calcification (CAC) and periodontal risk in nonsmoker subjects by using panoramic radiographs (DPR).Materials and Methods:A total of 1146 DPRs were investigated. Gender, age, severity of bone loss, tooth loss, periodontal risk, and findings of carotid calcification were recorded. The periodontal risk was evaluated and classified according to the degree of alveolar bone loss.Results:CAC was diagnosed in %13.6 (n: 156) of DPRs. Of 1146 patients, 338 (29.5%) had low, 668 (60%) had moderate, and 120 (10.5%) had high periodontal risk. A statistically significant relation was observed between carotid calcification and periodontal risk.Conclusion:Positive findings of carotid calcification may be related with periodontal problems. Clinicians must be careful about diagnosing CACs on DPRs during routine examinations. In the case of positive findings of CAC and periodontitis together, the patient may be consulted to a specialist for further investigation.

Aggregatibacter actinomycetemcomitans modulates toll-like receptors 2 and 4 in gingival epithelial cells in experimental periodontitis

Background: Periodontitis is a common bacterial infection precipitated by exaggerated host responses to the oral microorganisms, As the first cells to encounter the oral pathogens the gingival epithelial cells (GEC) respond via toll-like receptors (TLR) that recognize conserved microbial patterns. Here we investigated the expression of TLR-2 and TLR-4 in GEC of naοve mice in response to infection with the periodontal pathogen Aggregatibacter actinomycetemcomitans (Aa) . Methods: 7-9 weeks old mice were induced experimental periodontitis by inoculating the palatal gingival with 1x109 colony forming units of Aa. Mice were sacrificed 50 days later and intact maxilla harvested. The degree of alveolar bone loss was determined by micro-CT. Single suspensions of the epithelial cells isolated from palatal gingival tissues were assessed for the expressions of TLR-2 and TLR-4 proteins by flow cytometry and for TLR-2 and TLR-4 mRNA by reverse transcriptase PCR. Differences between the control and the disease groups were determined by students't- test. Results: Both TLR-2 and TLR-4 proteins were significantly elevated in the GEC of mice infected with A . actinomycetemcomitans when compared to the control group. The ratio of TLR-4 to TLR-2 mRNA was upregulated in chornic periodontitis as compared with the control group. Conclusion: Our data suggest that TLR-2 and TLR-4 are regulated differentially in A. actinomycetemcomitans-induced periodontitis.

Effects of Obesity on Gingival Oxidative Stress in a Rat Model

Studies indicate a correlation between obesity and periodontitis. Oxidative stress is involved in the progression of periodontitis. The purpose of this study was to investigate the effects of obesity on gingival oxidative stress in a rat periodontitis model. The obese Zucker rats (n = 14) and their lean littermates (n = 14) were each divided into two groups of seven rats. In one of each group, periodontitis was induced by ligature for 4 weeks, whereas the other group was left unligated. The level of 8-hydroxydeoxyguanosine and the ratio of reduced/oxidized glutathione were determined to examine gingival oxidative stress. The serum level of reactive oxygen metabolites and the gingival gene-expression pattern related to oxidative/metabolic stress, inflammation, and cell behavior were also evaluated. The obese rats weighed more than the lean rats at 4 weeks. Compared to lean rats, obese rats had enhanced gingival 8-hydroxydeoxyguanosine levels and a decreased ratio of reduced/oxidized glutathione in the gingival tissue, with increasing serum reactive oxygen metabolites. However, there were no significant differences in the degree of alveolar bone loss between lean and obese rats, except for teeth with and without ligatures in both rats. In addition, the periodontal lesion in obese rats showed higher 8-hydroxydeoxyguanosine levels and polymorphonuclear leukocyte infiltration than the inflamed ones in lean rats, with downregulation of multiple cytochrome P450 gene expression. Obesity induced gingival oxidative stress with increasing serum reactive oxygen metabolites in rats. In the periodontal lesion, gene expressions related to a capacity for xenobiotic detoxification were downregulated in the obese model.

Patient compliance with supportive periodontal therapy

Purpose: The purpose of this study was to evaluate the compliance to maintenance schedules recommended supportive periodontal therapy(SPT) and to determine differences in the characteristics of compliant and non-compliant patients. Methods: 414 patients commencing SPT after active periodontal treatment from 2003 to 2005 were included in this study. Based on their compliance with the suggested maintenance schedule, patients were classified as compliant and non-compliant groups. Also patients classified by gender, age, degree of alveolar bone loss and treatment rendered. The association between compliance and patient characteristics was assessed by odds ratio in logistic regression analyses. Results: Only 47% of the initial patient was found to be compliant at the end of August 2008 and 20.8% patients were lost in the first year of SPT. There were significant differences between compliant and non-compliant regard to age, degree of alveolar bone loss and treatment rendered. Conclusions: In conclusion, compliance with SPT generally poor and patients who were older, treated surgical therapy and with mild alveolar bone loss are more compliant to SPT. (J Korean Acad Periodontol 2009;39:193-198)

The Extent of Alveolar Bone Loss Is Associated With Impaired Glucose Tolerance in Japanese Men

The treatment of periodontal disease in diabetic patients is reported to have a beneficial effect on their glucose control. A recent study indicated that having deep pockets is significantly associated with past development of glucose intolerance in non-diabetic individuals using an oral glucose tolerance test (OGTT). These findings suggest that periodontal disease is a risk factor for diabetes, although more evidence is needed. A total of 193 Japanese men aged 50 to 54 years with at least 10 teeth were examined as part of a comprehensive health examination before retirement from the Japan Self-Defense Force. Alveolar bone loss of the posterior teeth was measured on a panoramic x-ray film. An OGTT was administered and impaired glucose tolerance (IGT) and diabetes were defined. The relationships between the mean ratio of alveolar bone loss to root length and OGTT results were analyzed after adjusting for known risk factors for diabetes. The proportion of subjects with IGT increased significantly in the subjects with higher tertiles of alveolar bone loss (P<0.05). In the multivariate logistic regression analysis excluding diabetic subjects, the adjusted OR for IGT to normal glucose tolerance (NGT) increased in subjects with higher tertiles of alveolar bone loss (P for trend=0.03). In the subjects with the highest tertile of alveolar bone loss, the adjusted OR for IGT to NGT was 4.27 (95% confidence interval [CI]: 1.41 to 12.9; P=0.01). The degree of alveolar bone loss is significantly associated with IGT, suggesting that periodontitis with alveolar bone loss is associated with impaired glucose tolerance.

Factors Affecting Postmortem Tooth Loss

Unassociated human bones are a particular problem during the exhumation of mass graves and a factor that limits anthropological and paleopathological analyses from archaeological contexts. Extensive anthropological literature has focused on the complex taphonomic factors that influences bone assemblages, but little attention has been paid to postmortem tooth loss and factors affecting this process. The following study focuses upon the influence of different factors on postmortem tooth loss. Three samples were investigated in the study: a medieval church cemetery containing 110 individual skeletal remains, and two samples from a series of mass graves made within the same time period in 1999, containing 402 bodies. The frequency of postmortem tooth loss was analyzed relative to postmortem interval for each sample, excavation methods, age distribution, and presence of bone loss associated with periodontal disease. Our results indicate that the degree of alveolar bone loss significantly affected both antemortem and postmortem tooth loss and that the frequency of postmortem tooth loss has the strongest correlation to time since death. These findings suggest that additional care should be taken when exhuming remains from older contexts.

Effect of smoking on resorption of residual alveolar ridges in complete denture wearers

Based on literature data it is obvious that there is a connection between smoking and periodontal diseases. Alveolar bone loss increases with smoking. Tobacco smoking affects the proportion of subgingival bacterial flora by influencing oxidoreduction potential of dental plaque and thus making conditions for development of anaerobic bacteria. According to some researchers, smoking affects the mineral component of bone tissue. Orthopantomograms show higher level of alveolar bone loss in smokers than in nonsmokers with the same level of oral hygiene. The aim of this study was to establish if smoking affects alveolar bone loss in complete denture wearers. Our clinical investigation included 60 patients of both sexes (30 smokers and 30 nonsmokers) all complete dentures wearers. All patients met study criteria: jaw relation and smokers who smoke over 20 cigarettes per day. All subjects were interviewed, and after that orthopantomograms were made. They were used to calculate the degree of alveolar bone loss. The examined subjects were approximately of the same age. Mean age of smokers was 59.9 and nonsmokers 61.8. It was established that differences regarding resorption in men were not significant. The degree of resorption in women smokers and women non-smokers was different, but differences were not significant. It has been proven that the number of cigarettes smoked per day is very important. It is considered that the risk of oral epithelial dysplasia increases when smoking more than 20 cigarettes per day. Considering our results regarding resorption of edentulous alveolar ridge in smokers and nonsmokers, we concluded that there were no significant differences. There are opinions in literature that smoking is not an etiological factor in resorption, but there are some opinions that smoking is connected with the degree of resorption in periodontium. The analyses of resorptive changes in edentuolous smokers were done only around implants and it was estimated that smoking has more influence than other clinical risk factors. On the bases of our research we may conclude that smoking does not directly affect the degree of resorption of edentulous alveolar ridge with complete denture wearers.

Associations between six DNA probe-detected periodontal bacteria and alveolar bone loss and other clinical signs of periodontitis

The purpose of the present study was to assess the associations between the presence and amounts of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, B. intermedius, Eikenella corrodens, Wolinella recta, and Fusobacterium nucleatum in the periodontal pocket and the degree of alveolar bone loss and other clinical signs of periodonitis, such as probing pocket depth, attachment level, and presence of bleeding on probing at the same site. The study material comprised 16 subjects with or without approximal sites showing longitudinal alveolar bone loss who were selected from a group of 142 subjects monitored radiographically over the past 4 years. In this group 105 sites were examined, of which 58 showed recent alveolar bone loss greater than or equal to 1 mm. Subgingival plaque was collected with absorbent paper points and hybridized with 32P-labeled DNA probes specific for the above-mentioned bacteria. The amount of each bacterial species was correlated with the degree of bone loss over time and the three clinical measurements by means of Spearman rank correlation. A. actinomycetemcomitans showed poor correlations with all three clinical signs of periodontal inflammation, whereas B. gingivalis and W. recta demonstrated significant positive correlations with the three clinical measurements and with attachment level and pocket depth, respectively. In addition, the amount of A. actinomycetemcomitans, B. gingivalis and W. recta showed significant positive correlation with the extent of alveolar bone loss at the site. In contrast, the amounts of B. intermedius, E. corrodens, and F. nucleatum showed negative correlations with all four measurements.(ABSTRACT TRUNCATED AT 250 WORDS)

Co-twin control study of the relationship between smoking and some periodontal disease factors.

The study was based on 164 twin pairs from the older cohort of the Swedish twin registry. The main purpose of the study was to analyze previously recorded data concerning gingival bleeding in members of twin pairs with differing smoking exposure. Other periodontal disease factors analyzed were plaque index, alveolar bone index and tooth loss. It was found that the degree of alveolar bone loss and the number of teeth lost were greater in twins with a high life-time smoking exposure than in their twin partners with a low life-time exposure. Contrary to expectation, it was found that gingival bleeding propensity was less prevalent in the high exposure group. It is concluded that the validity of gingival bleeding as a sign and a symptom of inflammatory periodontal disease may be reduced as a consequence of smoking.

Periodontal disease in gnotobiotic rats.

The present investigation was carried out in order to assess the development of periodontal disease in germfree rats infected with microorganisms associated with human gingivitis, periodontitis and periodontosis lesions. One hundred and forty gnotobiotic rats of the Spraque‐Dawley strain were weaned 21 days after birth and then randomly divided into five groups (four experimental groups and one control) consisting of 28 animals each. After weaning the animals of the experimental groups were infected with one of the following strains; strain I (Actinomyces naeslundii), strain 1073 (Eikenella corrodens), strain 381 (Bacteroides asaccharolyticus), strain 4 (Capnocytophage sputigena). Animals were sacrificed to provide specimens for examination 14, 28, 56 and 84 days after infection. Germ‐free controls were sacrificed at the same time intervals.The degree of alveolar bone loss was assessed on defleshed and dried jaws. Microscopic assessments regarding loss of connective tissue attachment, degree of bone resorption, and degree of impaction of hair and bedding material were determined in histological sections. In addition, a morphometric analysis of the gingival tissues was carried out using a standardized morphometric test procedure.The results showed that germfree rats monoinfected with different bacteria associated with human periodontal diseases may suffer severe breakdown of the periodontal tissues. The degree of breakdown tended to increase with increasing experimental time. However, periodontal tissue destruction was obviously related to the impaction of hair and bedding material. In fact, only in areas with severe impaction of foreign material could gross destruction of the supporting apparatus be recognized.

唾液の粘度と歯周疾患との関係

The correlation between the viscosity of the whole saliva and its mucin concentration or the degree of clinical findings in patients suffering from periodontal diseases was investigated.Clinical findings were examined in the facial surface of the four first fully erupted molars, and in the facial surface of the maxillary right central incisor and mandibular left central incisor as follows: The plaque and calculus score was determined by Green-Vermillion's method; the degree of gingival inflammation was examined by a modification of Schour-Massler's method; the degree of alveolar bone loss was measured on X-ray photos by method of Schei et al.; and the depth of periodontal pockets was measured with a pocket maker. The periodontal condition was classified into four categories on the basis of clinical findings and X-ray photos as follows: simple gingivitis, slight periodontitis, moderate periodontitis and advanced periodontitis. Healthy dental students were selected as control subjects in this study.The viscosity of whole saliva was measured by a cone-plate viscometer: immediately after collection the saliva was centrifuged for 10min. at 2, 000g, and 1.5ml of its supernatant was submitted for measurement of the viscosity at 4°C under the shear rate of 9.6sec-1. Protein and sugar contents of the salivary mucin were measured by Lowry's and Anthron's methods, respectively.The following results were obtained:1. The salivary viscosity was found to be the highest between 31 and 40 years of age.2. There was no significant difference in the viscosity between males and females.3. Although the viscosity tended to be high at pH range from 6.5 to 7.0, there was no statistically significant correlation between the pH and the viscosity.4. The salivary viscosity in patients suffering from periodontal diseases was higher than that of normal subjects, except those of simple gingivitis. Moreover, there was a significant increment of the viscosity with the progress of the disease.5. The salivary mucin content was significantly higher than that of normal subjects and a statistically significant positive correlation was found between the viscosity and the salivary mucin content.6. A statistically significant positive correlation was found between the salivary viscosity and the depth of periodontal pocket, and between the salivary viscosity and the degree of alveolar bone loss.7. A statistically significant positive correlation was found between the protein content on one hand, and the calculus score, the depth of periodontal pocket, or the degree of alveolar bone loss on the other.8. A statistically significant positive correlation was found between the sugar content on one hand, and the plaque score, the calculus score, or the degree of alveolar bone loss on the other.It was concluded that the viscosity of the whole saliva is closely related to the salivary mucin content, various clinical findings and periodontal condition.

Alveolar bone loss and tooth attrition in skulls from different population samples.

614 skulls were examined, comprising 49 australoids, 80 negroids, 66 mongoloids and 419 caucasoids. The degree of alveolar bone loss was significantly greater in negroids and australoids than caucasoids or mongoloids. Also the degree of alveolar bone loss decreased between Romano‐British and 19th. century times in caucasoids. A similar pattern of variation was noted in the degree of tooth attrition. The results from this study are not sufficient, however, to assess whether the variation between the various population samples reflect genetic or environmental factors.

Correlation of Degree of Alveolar Bone Loss with Other Factors for Determining the Removal or Retention of Teeth

Correlation of Degree of Alveolar Bone Loss with Other Factors for Determining the Removal or Retention of Teeth