Bone mineral content and bone metabolism in young adults with severe periodontitis

Jaw osteoporosis: Challenges to oral health and emerging perspectives of treatment

Osteoporosis is a prevalent bone metabolic disease that poses a significant challenge to global human health. Jaw osteoporosis, characterized by microstructural damage of the jaw resulting from various factors, is one of the common manifestations of this condition. Recent studies have demonstrated that jaw osteoporosis has multifaceted effects on oral health and can negatively impact conditions such as periodontitis, oral implantation, orthodontic treatment, and wound healing. However, there are still some limitations in the conventional treatment of osteoporosis. For instance, while bisphosphonates can enhance bone quality, they may also lead to osteonecrosis of the jaw, which poses a potential safety hazard in oral diagnosis and treatment. In recent years, considerable attention has been focused on improving the pathological condition of jaw osteoporosis. Treatment strategies such as gut microbial regulation, extracellular vesicles, molecular targeted therapy, herbal medicine, mechanical stimulation are expected to enhance efficacy and minimize adverse reactions. Therefore, understanding these effects and exploring novel treatments for jaw osteoporosis may provide new insights for oral health maintenance and disease treatment. This article reviews the impact of jaw osteoporosis on oral health and describes the limitations associated with current methods. It also discusses emerging perspectives on treatment, offering a comprehensive overview of the challenges and future directions in managing jaw osteoporosis.

Diagnostic Accuracy of Urinary Biomarkers in Periodontitis: A Systematic Review and Meta-Analysis

Background

Biomarkers can be measured in various biological samples. Urine is among the most useful biofluids for routine testing, and several experimental and clinical studies support its role as a tool for the diagnosis and prevention of various diseases. The present systematic review aimed to examine periodontitis-specific urine biomarkers that could have a diagnostic relevance and to provide a qualitative assessment of the current literature.

Materials and Methods

Relevant studies identified from PubMed, Embase, Cochrane Library, and Scopus databases were examined to answer the following PECO question: "Could the concentration of specific metabolites in the urine be related to periodontal health and what is their diagnostic accuracy?". Quality of included studies was rated using ROBINS-I tool. Meta-analysis was conducted on available quantitative data.

Results

After the screening of 768 titles, five studies were included in qualitative synthesis. The studies included referred to the evaluation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and neopterin. Meta-analysis was conducted for neopterin concentration on data available in four studies involving 129 participants. Higher concentrations of neopterin were found in periodontitis-affected patients compared to controls and patients treated for periodontitis.

Conclusions

The literature appears controversial in attributing a role to neopterin and 8-OHdG as periodontal biomarkers, highlighting the need for further clinical studies on this topic. While some studies report variations in 8-OHdG and neopterin levels in periodontally affected patients versus either controls or periodontally treated patients, the level of evidence appears still limited to draw firm conclusions (PROSPERO CRD42020222681).

Hypoxia dissociates HDAC6/FOXO1 complex and aggregates them into nucleus to regulate autophagy and osteogenic differentiation

OBJECTIVE

This research aimed to elucidate the molecular mechanisms underlying the periodontitis-associated bone loss, with particular emphasis on the contributory role of hypoxic microenvironment in this process.

BACKGROUND

Periodontitis generally causes alveolar bone loss and is often associated with a hypoxic microenvironment, which affects bone homeostasis. However, the regulating mechanism between hypoxia and jaw metabolism remains unclear. Hypoxia triggers autophagy, which is closely related to osteogenic differentiation, but how hypoxia-induced autophagy regulates bone metabolism is unknown. HDAC6 and FOXO1 are closely related to bone metabolism and autophagy, respectively, but whether they are related to hypoxia-induced bone loss and their internal mechanisms is still unclear.

METHODS

Established rat nasal obstruction model and hypoxia cell model. Immunohistochemistry was performed to detect the expression and localization of HDAC6 and FOXO1 proteins, analysis of autophagic flux and transmission electron microscopy was used to examine the autophagy level and observe the autophagosomes, co-immunoprecipitation and chromatin immunoprecipitation were preformed to investigate the interaction of HDAC6 and FOXO1.

RESULTS

Hypoxia causes increased autophagy and reduced osteogenic differentiation in rat mandibles and BMSCs, and blocking autophagy can attenuate hypoxia-induced osteogenic differentiation decrease. Moreover, hypoxia dissociated the FOXO1-HDAC6 complex and accumulated them in the nucleus. Knocking down of FOXO1 or HDAC6 alleviated hypoxia-induced autophagy elevation or osteogenic differentiation reduction by binding to related genes, respectively.

CONCLUSION

Hypoxia causes mandibular bone loss and autophagy elevation. Mechanically, hypoxia dissociates the FOXO1-HDAC6 complex and aggregates them in the nucleus, whereas HDAC6 decreases osteogenic differentiation and FOXO1 enhances autophagy to inhibit osteogenic differentiation.

Regenerative Potential of Hydroxyapatite-Based Ceramic Biomaterial on Mandibular Cortical Bone: An In Vivo Study

Reconstruction of bone defects and maintaining the continuity of the mandible is still a challenge in the maxillofacial surgery. Nowadays, the biomedical research within bone defect treatment is focussed on the therapy of using innovative biomaterials with specific characteristics consisting of the body’s own substances. Hydroxyapatite ceramic scaffolds have fully acceptable phase compositions, microstructures and compressive strengths for their use in regenerative medicine. The innovative hydroxyapatite ceramics used by us were prepared using the tape-casting method, which allows variation in the shape of samples after packing hydroxyapatite paste to 3D-printed plastic form. The purpose of our qualitative study was to evaluate the regenerative potential of the innovative ceramic biomaterial prepared using this method in the therapy of the cortical bone of the lower jaw in four mature pigs. The mandible bone defects were evaluated after different periods of time (after 3, 4, 5 and 6 months) and compared with the control sample (healthy cortical bone from the opposite side of the mandible). The results of the morphological, clinical and radiological investigation and hardness examination confirmed the positive regenerative potential of ceramic implants after treatment of the mandible bone defects in the porcine mandible model.

Three-dimensional Analysis of Alveolar Bone With and Without Periodontitis

OBJECTIVE

The aim of this study was to investigate the alveolar bone density and thickness in Chinese participants with and without periodontitis.

METHODOLOGY

This study was retrospective and cross-sectional in nature and used cone-beam computed tomography (CBCT) to evaluate alveolar bone loss, bone density, and bone thickness around 668 mandibular molars (344 periodontally healthy teeth and 324 teeth with periodontitis). Comparative statistical tests were done related to the age, sex, tooth type, tooth side, and degree of bone loss. The significance level was set to be P < .05.

RESULTS

The alveolar bone density significantly differed between the healthy and periodontitis groups (mean difference = 24.4 Hounsfield units; P = .007). Similarly, the alveolar bone thickness of the healthy group was significantly higher than that of the periodontitis group (4.6 ± 1.8 mm compared to 4.2 ± 1.1 mm). Teeth in females demonstrated a significantly (P ˂ .001) higher bone density compared with males in both healthy and compromised groups. However, males showed a significantly (P ˂ .05) thicker bone of the teeth than females in relation to the healthy group. The alveolar bone density and thickness in both healthy and periodontitis groups significantly differed between the first and the second molars (P < .001). The alveolar bone thickness had a highly significant difference (P < .001) between the different degrees of bone loss.

CONCLUSIONS

Alveolar bone thickness and density were reduced at periodontally diseased teeth.

Low bone mineral density is associated with severe periodontitis at the end of the second decade of life: A population-based study

AIM

To evaluate the association between low bone mineral density (BMD) and severe periodontitis at the end of the second decade of life.

MATERIALS AND METHODS

This population-based study analysed 2032 youngers (18-19 years old) of the RPS cohort. BMD of lumbar spine (BMD-LS) and of the whole body (BMD-WB) were assessed by dual x-ray emission densitometry. Low BMD-LS (Z-score ≤ -2) and low BMD-WB (Z-score ≤ -1.5) were correlated with severe periodontitis. The extent of periodontal disease was also evaluated as the following outcomes: proportions of teeth affected by clinical attachment loss ≥5 mm and probing depth ≥5 mm. Multivariate models by sex, education, family income, risk of alcohol dependence, smoking, plaque, bleeding index, and body mass index were estimated through logistic regression (binary outcomes) and Poisson regression (continuous outcomes).

RESULTS

The prevalence of severe periodontitis was 10.97%. Low BMD-LS (odds ratio [OR] = 2.08, confidence interval [CI] = 1.12-3.85, p = .01) and low BMD-WB (OR = 1.34, CI = 1.001-1.81, p = .04) were associated with severe periodontitis in the final multivariate models. Low BMD-LS and BMD-WB were also associated with a greater extent of periodontitis (p < .05).

CONCLUSIONS

Low BMD was found to be associated with the severity and extent of periodontitis in adolescents. Adolescents at peak bone mass age presenting low BMD are more likely to be affected by severe periodontitis.

Periodontal inflammation triggers a site-specific and wide radius of calcium metabolic effects on alveolar bone

BACKGROUND AND OBJECTIVE

There is a close relationship between inflammation and bone remodeling in the periodontium. However, previous studies have not delineated the alterations in calcium (Ca) metabolism during periodontitis progression. The aim of this current investigation was to examine Ca dynamics in alveolar bone of rats during progression of ligature-induced periodontal inflammation by using ⁴⁵ Ca, which is an index of hard tissue neogenesis.

MATERIAL AND METHODS

To induce periodontitis, the maxillary right first molar (M1) of 8-week-old male rats was ligated with a silk suture for 1, 3, 7, and 28 days. The left M1 was not ligated as a control. To evaluate resultant changes in bone neogenesis, ⁴⁵ CaCl₂ was injected intraperitoneally 24 hours before euthanasia. The left-and-right palatal mucosa, molar teeth (M1 and M2), and alveolar bone were harvested for evaluation of ⁴⁵ Ca radioactivity using a liquid scintillation counter. The distribution of ⁴⁵ Ca in maxillary tissues was evaluated using autoradiography (ARG). In addition, we analyzed the bone volume fraction (BV/TV) and bone mineral density (BMD) of the alveolar bone by micro-computed tomography. To investigate the number of osteoclasts and osteoblasts, tartrate-resistant acid phosphatase (TRAP) and bone-specific alkaline phosphatase (BAP) were measured by an enzymatic assay and immunohistochemistry, respectively.

RESULTS

⁴⁵ Ca radioactivity in the alveolar bone of the ligature side decreased by 8% compared to the unligated control-side on day 1, whereas on day 7, it markedly increased by 33%. The ⁴⁵ Ca levels in the gingival tissue and molar teeth were slightly but significantly lower than the control-side on day 1 and higher from day 3 to 28. The variation in ⁴⁵ Ca levels for the alveolar bone was greater and specific compared with other tissues. Furthermore, on day 7, ARG data revealed that ⁴⁵ Ca on the control side was primarily localized to the periodontal ligament (PDL) space and alveolar bone crest and barely detected in the gingival tissues and deeper parts of the alveolar bone. On the ligature side, ⁴⁵ Ca disappeared from the PDL and alveolar crest, but instead was broadly and significantly increased within the deeper zones of the alveolar bone and furcation areas and distant from the site of ligature placement and periodontal inflammation. In the shallow zone of the alveolar bone, these changes in ⁴⁵ Ca levels on day 7 were consistent with decreases in the bone structural parameters (BV/TV and BMD), enhanced osteoclast presence, and suppressed levels of BAP expression in osteoblasts. In contrast, the deep zone and furcation area showed that TRAP-positive cells increased, but BAP expression was maintained in the resorption lacunae of the alveolar bone.

CONCLUSION

During periodontitis progression in rats, ⁴⁵ Ca levels in the alveolar bone exhibited biphasic alterations, namely decreases and increases. These data indicate that periodontitis induces a wide range of site-specific Ca metabolism alterations within the alveolar bone.

Correlations between the Peptide Hormone Ghrelin and Proinflammatory Cytokines in Experimental Periodontitis Models of Female Rats at Different Stages of the Life Cycle

OBJECTIVE

The aim of this study was to examine the correlations between the levels of ghrelin and inflammatory and bone metabolism markers in rats with periodontitis.

DESIGN

Thirty female Wistar rats (6 trial rats and 4 control rats in each group) were divided into pubertal, adult and postmenopausal groups. Periodontitis was induced by ligatures. On the 21 st day, blood was collected and all rats were then sacrificed. The levels of osteocalcin, osteoprotegerin, alkaline phosphatase, tumour necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β), acylated ghrelin, total ghrelin and soluble receptor activator of nuclear factor-kB ligands in the blood samples were measured using enzyme-linked immunosorbent assays. The jaws were decalcified in a Tris-EDTA solution and embedded in paraffin and 4-5 μm sections were cut for IL-β, TNF -α and ghrelin staining.

RESULTS

Significantly higher serum alkaline phosphatase levels were detected in the trial rats in the pubertal group than in the control rats (p = 0.033). In the postmenopausal group, ghrelin levels positively correlated with interleukin 1 beta levels (r = 0.708, p < 0.05). Among all trial rats, the postmenopausal group exhibited significantly higher levels of acylated ghrelin than the other groups (p = 0.001). Significantly higher osteoprotegerin levels were observed in the control rats than in the trial rats in the postmenopausal group (p = 0.012). Inflammation scores were significantly higher in adult trial rats than in controls (p = 0.024); significantly higher TNF-α levels were detected in postmenopausal experimental rats than in the adult experimental group (p = 0.025).

CONCLUSIONS

We concluded that total ghrelin levels in serum only correlated with IL-β levels in postmenopausal rats.

Vertical ridge augmentation using a porous composite of uncalcined hydroxyapatite and poly-DL-lactide enriched with types 1 and 3 collagen

BACKGROUND

Previous studies have shown that porous composite blocks containing uncalcined hydroxyapatite (u-HA; 70 wt%) with a scaffold of poly-DL-lactide (PDLLA, 30 wt%) are biodegradable, encourage appropriate bone formation, and are suitable for use as a bone substitute in vertical ridge augmentation. The present study aimed to accelerate osteogenesis in vertical ridge formation by adding types 1 and 3 collagen to the u-HA/PDLLA blocks and assessing the effect.

MATERIAL AND METHODS

The bone substitute in the present study comprised porous composite blocks of u-HA (70 wt%) with a PDLLA (27-29 wt%) scaffold and enriched with types 1 and 3 collagen (1.7 ~ 3.4 wt%). The control blocks were composed of u-HA (70 wt%) and PDLLA (30 wt%). The materials were formed into 8-mm diameter, 2-mm high discs and implanted onto the cranial bones of six rabbits. The animals were sacrificed 4 weeks after implantation, and histological and histomorphometrical analyses were performed to quantitatively evaluate newly formed bone.

RESULTS

New bone formation occurred with both block types, showing direct contact with the original bone. Mean ± standard deviation bone formation was significantly greater in the experimental blocks (25.6% ± 4.8%) than in the control blocks (17.0% ± 4.7%).

CONCLUSIONS

Histological and histomorphometrical observations indicated that new bone was formed with both block types. The u-HA/PDLLA block with types 1 and 3 collagen is a more promising candidate for vertical ridge augmentation than the u-HA/PDLLA alone block.

Osteoporosis and Periodontitis in Postmenopausal Women: A Systematic Review

This systematic review was done to assess the strength of association between osteoporosis and chronic periodontitis in postmenopausal women, assessed by bone mineral density (BMD) and clinical attachment loss, respectively. The Pubmed, Cochrane central, EMBASE, and Google Scholar were searched from year 1990 to 2015 for studies on association between chronic periodontitis and osteoporosis. Studies measuring osteoporosis in terms of central BMD and periodontitis in terms of clinical attachment level were studied. Data were extracted and descriptive analysis was performed. Screening of 1188 articles resulted in 24 articles for review after reading the titles and abstracts. Fifteen studies were shortlisted for inclusion in systematic review. Ten of these studies showed an association between periodontitis and osteoporosis. It implies that patients with severe periodontitis should also be evaluated for systemic bone health and vice versa.

Tobacco consumption induces alveolar crest height loss independently of mandibular bone mass and bone density

AIM

To investigate the relationship of tobacco consumption with alveolar crest height (ACH) loss and mandibular bone mass estimated by digital panoramic radiography and cone-beam computed tomography (CBCT).

MATERIAL AND METHODS

We studied 315 patients (43.2% [n = 136] men and 56.8% [n = 179] women) with mean age of 36.6 ± 5.3 (range 21-30 years (16.2%), range 31-46 years (83.8%); 9% (n = 71) were smokers (>10 cig./day). A mean of 13.0 ± 2.0 mandibular teeth were present: 37.5% of patients had 6-12 teeth and 62.5% 13-16 teeth. We analyzed 315 digital panoramic radiographs (2D) and calculated the ACH, mandibular cortical width, and basal and alveolar bone gray level values. ACH and bone density were also measured on CBCT (3D) in the 110 patients scheduled for implantation.

RESULTS

In the univariate analysis, ACH loss was greater in older patients (P = 0.012) and in those with fewer mandibular teeth (P < 0.001) and showed a relationship with tobacco consumption that was close to significant (P = 0.079). In the multivariate analysis, the number of mandibular teeth (P < 0.001) and tobacco consumption (P = 0.048) were significantly associated with ACH. Alveolar and basal bone densities were associated, respectively, with number of mandibular teeth (P = 0.012) and cortical width (P = 0.030).

CONCLUSION

In a Caucasian population aged 21-46 years, tobacco consumption was significantly associated with ACH loss. However, ACH loss showed no significant relationship with mandibular bone mass estimated either as mandibular cortical width index or bone density on digital panoramic radiographs or as bone density on CBCT. ACH loss was a local event independent of mandibular bone mass status.

Comparison of bone mineral density in the jaws of patients with and without chronic periodontitis

OBJECTIVES

Although several studies have addressed the relationship between systemic bone mineral status and the severity of periodontitis, there is little knowledge of the relationship between periodontal disease and locally detected bone mineral density. The aim of this study was to compare the mandibular bone mineral density of patients with chronic periodontitis with that of periodontally healthy subjects.

METHODS

48 systemically healthy subjects were included in the study and underwent a periodontal examination to determine their status. 24 subjects were periodontally healthy and the other 24 had moderate or severe chronic periodontitis. The mandibular bone mineral density of the subjects was determined by dual energy X-ray absorptiometry. The region of interest on the body of the mandible was independently determined on the dual energy absorptiometry radiographs, and a computer calculated the bone mineral density of these regions.

RESULTS

The mandibular bone mineral density of the subjects with periodontitis was significantly lower than that of the periodontally healthy subjects (p < 0.01). There were significant negative correlations between the mandibular bone mineral density values and parameters related to the amount of periodontal destruction.

CONCLUSIONS

Low bone mineral density in the jaw may be associated with chronic periodontitis.

Alveolar bone level is not associated with vitamin D receptor gene polymorphism and bone density in mandible

The objective of this study was to determine, using digital panoramic radiographs, whether the bone level at the alveolar crest is related to the mandibular bone density and/or to vitamin D receptor (VDR) gene polymorphisms. We analyzed 319 digital panoramic radiographs from the same number of patients. Alveolar bone level was expressed as percentage of root length. The mandibular cortical width index was calculated as a measure of mandibular bone density, and, in 72 randomly selected cases, the haplotype of the VDR gene (BsmL) was determined by polymerase chain reaction. Alveolar bone level was not related to the mandibular cortical width index (p = 0.568) or VDR gene expression (p = 0.575). Bone loss was greater in smokers than in non-smokers (p = 0.036), and the mandibular cortical width index was higher in males (p = 0.04), the older age group (p = 0.032), and in those with more teeth (p = 0.01). Multivariate analysis confirmed the association between these variables and alveolar bone loss. Alveolar bone loss showed no significant relationship with the mandibular bone density evaluated on digital panoramic radiographs or with VDR genotype (BsmL) in Caucasian females and males aged under 47 years.

Effect of defective collagen synthesis on epithelial implant interface: lathyritic model in dogs. An experimental preliminary study

Peri-implant mucosa is composed of 2 compartments: a marginal junctional epithelium and a zone of connective tissue attachment. Both structures consist mainly of collagen. Lathyrism is characterized by defective collagen synthesis due to inhibition of lysyl oxidase, an enzyme that is essential for interfibrillar collagen cross-linking. The lathyritic agent beta-aminoproprionitrile (β-APN) is considered a suitable agent to disrupt the connective tissue metabolism. Therefore, the purpose of this study was to assess the effect of defective connective tissue metabolism on epithelial implant interface by using β-APN created chronic lathyrism in the canine model. Two 1-year-old male dogs were included in this study. A β-APN dosage of 5 mg/0.4 mL/volume 100 g/body weight was given to the test dog for 10 months, until lathyritic symptoms developed. After this, the mandibular premolar teeth (p2, p3, p4) of both dogs were atraumatically extracted, and the investigators waited 3 months before implants were placed. In the test dog, 3 implants were placed in the left mandible, and 2 implants were placed in the right mandible. In the control dog, 2 implants were placed in the left mandibular premolar site. The dogs were sacrificed 10 months after healing. Peri-implant tissues obtained from the dogs were examined histomorphologically and histopathologically. Bone to implant contact (BIC) values and bone volumes (BV) were lower in the lathyritic group compared to the control group; however, no statistical significance was found. Significant histologic and histomorphometric changes were observed in peri-implant bone, connective tissue, and peri-implant mucosal width between test and control implants. Defective collagen metabolism such as lathyrism may negatively influence the interface between implant and surrounding soft tissue attachment.

Determination of bone quality of 372 implant recipient sites using Hounsfield unit from computerized tomography: a clinical study

BACKGROUND

The type and architecture of bone are very important factors in the successful implant treatment, and it is manifested that higher implant failure is more likely in the poorer quality of bone. Conventional bone classifications have recently been questioned because they are subjective and retrospective.

PURPOSE

This clinical study aimed to determine the variations of the bone density in dental implant recipient sites using computerized tomography (CT).

MATERIALS AND METHODS

The study group comprised of randomly selected 140 patients with 372 implant sites. Recipient sites for implant placement were determined based on CT data using implant planning StentCad software (Media Lab Software, La Spezia, Italy). The mean bone density values in Hounsfield unit (HU) of the simulated implant areas were recorded using the StentCad software.

RESULTS

The HU values ranged from 68 to 1,603 HU. It was found that mean bone density values were 927 +/- 237, 721 +/- 291, 708 +/- 277, and 505 +/- 274 HU in the anterior mandible, posterior mandible, anterior maxilla, and posterior maxilla, respectively.

CONCLUSION

Preoperative CT examination may be a useful method for determining the bone density of recipient areas before implant placement, and this valuable information about bone quality helps clinicians to make better treatment planning regarding the implant positions.

No alteration in bone mineral density in patients with periodontitis

Alveolar bone destruction can be magnified in the presence of generalized skeletal disorders. We questioned whether severe generalized periodontitis patients display signs of bone metabolism disturbances. Our objective was to assess skeletal bone mineral density (BMD) and biochemical bone parameters in premenopausal women with periodontitis. Forty-five patients and 40 control individuals were included in the study. We measured BMD by dual-energy x-ray absorptiometry. The results showed no difference in BMD values between the periodontitis and control groups (p > 0.05). A positive relationship between the clinical attachment level and Body Mass Index (BMI) scores was observed (p = 0.03). Increased serum creatinine levels were noted in the periodontitis group (p = 0.04). Analysis of the data suggests that there is no evidence for an association between skeletal BMD and severe periodontitis in premenopausal women. There may be a link between elevated creatinine levels and periodontitis. The persons with high BMI scores seemed to be at risk for periodontitis.

Relations between the bone density values from computerized tomography, and implant stability parameters: a clinical study of 230 regular platform implants

AIMS

The objective of this study was to determine the relationship between bone density, insertion torque, and implant stability at implant placement.

MATERIALS AND METHODS

One-hundred and eight patients were treated with 230 Brånemark System implants. A computerized tomography (CT) machine was used for pre-operative evaluation of the jaw bone for each patient. The maximum insertion torque values were recorded with the OsseoCare equipment. Implant stability measurements were performed with the Osstell machine for only 142 implants.

RESULTS

The mean bone density and insertion torque values were 721+/-254 Hounsfield unit (HU) and 39.1+/-7 N cm for 230 implants, and the correlation was significant (r=0.664, p<0.001). The mean bone density, insertion torque, and resonance frequency analysis values were 751+/-257 HU, 39.4+/-7 Nc m, and 70.5+/-7 implant stability quotient (ISQ), respectively, for 142 implants. Statistically significant correlations were found between bone density and insertion torque values (p<0.001); bone density and ISQ values (p<0.001); and insertion torque and ISQ values (p<0.001).

CONCLUSION

The bone density values from pre-operative CT examination may provide an objective assessment of bone quality, and significant correlations between bone density and implant stability parameters may help clinicians to predict primary stability before implant insertion.

Bone density assessments of oral implant sites using computerized tomography

The type and architecture of bone are considered to affect its load-bearing capacity and it has been indicated that poorer quality bone is associated with higher implant failure rates. To date, bone classifications have only provided subjective methods for pre-operative assessment, which can be considered unreliable. The aim of this study was to evaluate variations of the bone density in designated endosseous implant sites using computerized tomography. One hundred and thirty-one designated implant sites in 72 patients were utilized. Computerized tomography results indicated that bone densities may vary markedly when different areas of a designated implant site are compared. It has been observed that a difference in the bone density exists for the four regions within the oral area, with the anterior mandible yielding mean density values of 944.9+/-207 Hounsfield units (HU)>anterior maxilla, 715.8+/-190 HU>posterior mandible, 674.3+/-227 HU>posterior maxilla and 455.1+/-122 HU. Computerized tomography may be a useful tool for determining the bone density of interest areas before implant placement, and this valuable information about the bone quality provides dental practitioners to make better treatment planning regarding the implant positions.

Comparison of platelet pellet and bioactive glass in periodontal regenerative therapy

OBJECTIVE

In recent years, platelet-rich plasma combined with graft materials has been used for periodontal regeneration. The individual role of blood products with guided tissue regeneration in periodontal regenerative therapy is unclear and needs to be elucidated. The purpose of this study was to compare the clinical and radiological effectiveness of platelet pellet/guided tissue regeneration (PP/GTR) and bioactive glass/GTR (BG/GTR) treatments in patients with periodontal disease.

MATERIAL AND METHODS

Using a split mouth design, 15 chronic periodontitis patients with pocket depths > or = 6 mm following periodontal initial therapy were randomly assigned to treatment with a combination of PP/GTR or BG/GTR in contralateral dentition areas. An absorbable membrane of polylactic acid was used GTR. The criteria for the comparative study were preoperative and postoperative 6 months pocket depth, clinical attachment level, and radiological alveolar bone level.

RESULTS

Both treatment modalities resulted in significant pocket depth reduction and gain in clinical attachment and alveolar bone level compared to the preoperative values (p < 0.01). Reduction in pocket depth, gain in clinical attachment and alveolar bone level were 4(3-6), 4.1+/-0.7, 4.9+/-1.4 mm in the PP/GTR group and 4(3-7), 4.1+/-1.2, 5.9+/-1.7 mm in the BG/GTR group, respectively. The differences between the two groups were not statistically significant (p > 0.05).

CONCLUSIONS

Within the limits of this study, it was concluded that PP may be effective as a bioactive glass graft material and used as a graft material for treating intrabony defects. PP thus appears to be a suitable alternative in the regenerative treatment of intrabony periodontal defects.

Significance of osteoporosis in craniomaxillofacial surgery: a review of the literature

Osteoporosis is a common problem in orthopedic surgery. The purpose of this review of the literature was to examine whether osteoporosis is also an important factor in patient treatment in the field of craniomaxillofacial surgery. Emphasis was given to the consequences of osteoporosis for the maxilla and mandible, the influence of osteoporosis on fracture treatment, the use of dental implants, the importance of soft tissues and the effect of osteoporosis therapies. It was found that osteoporosis does affect the bones of the skull. The effect of osteoporosis on treatment, however, is controversial and necessitates better ways of quantifying bone loss. Large inter-individual and site-specific differences in bone density, as well as other effects such as removal of teeth, periodontitis, implant insertion, augmentation procedures and altered loading with dystrophic consequences need to be considered in future studies. Special attention should be given to osteoporosis during fracture treatment.