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

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.

Head & Neck Trauma in the Geriatric Population

Craniofacial trauma in the geriatric population is increasing as our population ages. Due to loss of bone quality and medical comorbidities, injuries for minor trauma can be severe. A more extensive medical evaluation is usually warranted in this population before proceeding with surgery. In addition, unique surgical considerations exist in the repair of atrophic and edentulous bony fractures. Some quality improvement measures have already been undertaken but more is needed to help standardize care in this vulnerable population.

The Effects of Statins on Bone Formation Around Implants Placed in Animal Bones: A Systematic Review and Meta-Analysis

Background

Implants are preferred for replacement of missing teeth by the clinicians as well as the patients. Lesser alveolar bone density doesn't preclude any individual for choosing this option but warrants for extra caution. Preclinical studies have explored the osteoinductive potential of statins, but results should be analyzed vigorously before implementing them in humans. There is no meta-analysis to document effect of statins on bone formation around implants in osteoporotic animals.

Methods and material

PubMed, Embase and Cochrane were searched for studies investigating the effect of statins on bone implant contact (BIC %), bone mineral density (BMD %) and bone volume (BV %) around implants at 2, 4 and 12 weeks. Meta-analysis was performed on subgroups with osteoporotic animals which were administered statins through different routes.

Results

Quantitative data from 12 studies showed favorable effect of statins on bone around implants. Positive difference was observed at 4 weeks in BIC (parenteral [SMD = 4.33 (2.89, 5.77); I 2 = 3%)], BMD (local [SMD = 1.33 (0.51, 2.15); I 2 = 0%] and BV (local [SMD = 1.58 (0.76, 2.40); I 2 = 0%]. BIC [SMD = 1.40 (0.89, 1.90); I 2 = 0%] and BV [SMD = 3.91 (2.33, 5.50); I 2 = 43%] were higher in experimental group after 12 weeks of oral administration.

Conclusions

Statins can be investigated as potential bone graft materials to increase the predictability of osseointegration especially in osteoporotic individuals. Future research should focus to reproduce homogeneous data and conclusive recommendations which can be applied in clinical trials.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12663-023-01873-z.

Anatomical distribution of mandibular fractures from severe bicycling accidents: A 12-year experience from a Norwegian level 1 trauma center

Background/Aim

The mandible makes up a substantial part of the lower face, and is susceptible to injury. Even in helmeted cyclists, accidents may lead to fractures of the mandible because conventional helmets provide little protection to the lower part of the face. In addition, some studies indicate that helmets may lead to an increased risk of mandibular fractures. Thus, the aim of this study was to examine the anatomic distribution of mandibular fractures in injured cyclists and to assess if helmet use influenced the fracture locations.

Material and Methods

Data from a Norwegian Level 1 trauma center were collected in the Oslo University Hospital Trauma Registry over a 12‐year period. Of 1543 injured cyclists, the electronic patient charts of 62 cyclists with fractures of the mandible were retrospectively evaluated in detail. Demographic data, helmet use, and fracture type were assessed.

Results

Sixty‐two patients (4%) had fractures of the mandible, and women had an increased risk (OR 2.49, 95% CI 1.49–4.16, p < .001). The most common fracture site was the mandibular body, followed by the condyle. Isolated mandibular fractures occurred in 45% of the patients and 55% had other concomitant facial fractures. There were 42% of the patients with fractures in multiple sites of the mandible, and 42% had a concomitant dentoalveolar injury. Half of the cyclists were wearing a helmet at the time of the accident and 39% were not. There was no significant difference in fracture distribution between the helmeted and non‐helmeted groups.

Conclusions

Fracture of the mandibular body was the most prevalent mandibular fracture type following bicycle accidents. Women had an increased risk of mandibular fractures compared with men, whereas helmet wearing did not affect the anatomical fracture site.

Quality of Life in Menopausal Women with Dental Restorations and Implants

Aim:

This multicenter study examined the relationship, possible interactions, and intermittent effects that dental implants and prostheses can have on menopausal women’s quality of life as well as provided information regarding the possible side effects of therapeutic regimens on menopause and osteoporosis or osteopenia.

Materials and Methods:

Questionnaires consisted of selected quality of life questions based on specific and additional medical and dental (mainly prosthodontic) questions, which were administered to 100 Greek menopausal/post-menopausal women (Age: Mean Value=63,62 years old) with osteopenia or with or without osteoporosis, with dental implants and implant restorations, or conventional prosthetic restorations visiting two University Hospitals. Menopausal/post-menopausal status was judged on the basis of either secondary, definitive amenorrhoea or based on follicular stimulation hormone ​​(FSH) values, estradiol, and clinical risk factors.

Results:

Participants had a statistically significantly better “functional” and “psychological” feeling after prosthodontic rehabilitation with and without implants. Three out of four reported that their dentist informed them of the possible implant problems that might arise from osteoporosis and its treatment (medications). Moreover, osteopenia was found to be associated with a very lower problem percentage. The bisphosphonate treatment had the highest rate (80%) of reported implant problems than non-bisphosphonate treatment (30%). The hormone replacement therapy (HRT) for menopause was reported to be more associated with problems in implant placement (19%) than in those without treatment (27.3%).

Conclusion:

The questionnaires revealed a significant improvement concerning women’s life quality and well-documented information about the problems their dental implants and restorations may cause in association with menopause and/or osteoporosis.

Inhibition of miRNA-100 facilitates bone regeneration defects of mesenchymal stem cells in osteoporotic mice through the protein kinase B pathway

Osteoporotic patients suffer from bone microstructure damage and are prone to fracture and bone defect. Due to the damage of bone healing ability, the bone repair of osteoporotic patients is usually slow. Here we aimed to explore the function and potential molecular mechanism of miR-100 in osteogenic differentiation ability of bone marrow stem cells (BMSCs). Ovariectomy was performed on mice to induce osteoporosis. BMSCs were extracted from normal and ovariectomized (OVX) mice to examine the effect of microRNA (miR)-100 on BMSC osteogenic differentiation. Hematoxylin and eosin (H&E) staining and safranin O-fast green staining assays were performed on femur tissues to reveal pathological changes. The osteogenic differentiation of BMSCs were determined by Alkaline Phosphatase and Alizarin red staining assays. The results showed that miR-100 expression was significantly upregulated in bone tissues and BMSCs from osteoporotic mice. MiR-100 knockdown partially improved osteogenic function of OVX mice-derived BMSCs. Next, mechanistic target of rapamycin kinase (MTOR) was identified as the target downstream miR-100. MiR-100 deficiency can activate the protein kinase B (AKT)/mTOR pathway. MiR-100 controlled the osteogenic function of BMSCs by the AKT/mTOR pathway. Collectively, our findings demonstrate that inhibition of miR-100 facilitates bone regeneration defects of BMSCs in osteoporotic mice through AKT pathway, indicating that miR-100 might be an effective target for the treatment of osteoporotic mandibular injury and bone defect diseases.

Is Decreased Local Bone Quality an Independent Risk Factor for Complications Following Fracture Fixation of Facial Bones

PURPOSE

Although osteoporosis is associated with increased risks of complications of fracture fixation in the orthopedic literature, the association between local bone quality (LBQ) and complications of facial fracture fixation is unknown. The authors aim to identify that if decreased LBQ is an independent risk factor for complications following facial fracture fixation?

METHODS

The authors conducted a prospective cohort study on patients over age of 50 years who underwent open reduction and rigid internal fixation for facial fractures. The primary predictor was LBQ (low or normal), decided by a combination of 3 panoramic indices. Other predictors included age, gender, body mass index (BMI), comorbidities, trauma-related characteristics, etc. The outcome variable was the presence of hardware-related, fracture-healing, wound, or neurosensory complications during 2-year follow-up. Univariate and multivariate regressions were performed to identify any significant association between predictor and outcome variables.

RESULTS

The sample was composed of 69 patients (27 females) with an average age of 58.6 ± 8.6 years and BMI of 25 ± 3.8. Low-LBQ patients were significantly older, more females, had lower BMI, mainly injured from falls, had more complications compared to their normal-LBQ counterparts. However, multivariable logistic regressions demonstrated that only age (adjusted OR: 1.12, P = 0.031, 95% CI: 1.01, 1.23) and diabetes (adjusted OR: 12.63, P = 0.029, 95% CI: 1.3, 122.53) were significantly associated with overall complications after confounding adjustment.

CONCLUSIONS

The results of the present study indicate that reduced LBQ is not an independent risk factor for complications following facial fracture fixation. The increased risk of complications in low-LBQ patients is more likely to be attributed to other age-related comorbidities such as diabetes. Therefore, the authors recommend detailed workup and good control of comorbidities in elderly trauma patient.

Dental implants in patients with osteoporosis: a systematic review with meta-analysis

There is currently no consensus regarding the survival rate of osseointegrated implants in patients with osteoporosis. A systematic review with meta-analysis was performed to evaluate the survival rate of implants in such patients. The PubMed/MEDLINE, Web of Science, Cochrane Library, and SciELO databases were used to identify articles published up to September 2016. The systematic review was performed in accordance with PRISMA/PICO requirements and the risk of bias was assessed (Australian National Health and Medical Research Council scale). The relative risk (RR) of implant failure and mean marginal bone loss were analyzed within a 95% confidence interval (CI). Fifteen studies involving 8859 patients and 29,798 implants were included. The main outcome of the meta-analysis indicated that there was no difference in implant survival rate between patients with and without osteoporosis, either at the implant level (RR 1.39, 95% CI 0.93-2.08; P=0.11) or at the patient level (RR 0.98, 95% CI 0.50-1.89; P=0.94). However, the meta-analysis for the secondary outcome revealed a significant difference in marginal bone loss around implants between patients with and without osteoporosis (0.18mm, 95% CI 0.05-0.30, P=0.005). Data heterogeneity was low. An increase in peri-implant bone loss was observed in the osteoporosis group. Randomized and controlled clinical studies should be conducted to analyze possible biases.

Fixation Release and the Bone Bandaid: A New Bone Fixation Device Paradigm

The current gold standard of care for mandibular segmental defeat reconstruction is the use of Ti-6Al-4V immobilization hardware and fibular double barrel graft. This method is often successful immediately at restoring mandible function, however the highly stiff fixation hardware causes stress shielding of the grafted bone and stress concentration in the fixation device over time which can lead to fixation device failure and revision surgery. The purpose of reconstructive surgery could be to create normal stress trajectories in the mandible following engraftment. We investigate the use of a two stage mechanism which separates the immobilization/healing and regenerative phases of mandibular segmental defect treatment. The device includes the use of a very stiff, Ti-6Al-4V, releasable mechanism which assures bone healing. Therefore it could be released once the reconstructed boney tissue and any of its ligamentous attachments have completely healed. Underneath the released Ti-6Al-4V plate would be a pre-loaded nitinol (NiTi) wire-frame apparatus that facilitates the normal stress-strain trajectory through the engrafted bone after the graft is healed in place and the Ti-6Al-4V fixation device has been released. Due to the use of NiTi wires forming a netting that connects vascularized bone and possibly bone chips, bone grafts are also more likely to be incorporate rather than to resorb. We first evaluated a healthy adult mandible during normal mastication to obtain the normal stress-strain distribution. Then, we developed the finite element (FE) model of the mandibular reconstruction (in the M1-3 region) with the proposed fixation device during the healing (locked state) and post-healing (released state) periods. To recreate normal stress trajectory in the reconstructed mandible, we applied the Response Surface Methodology (RMS) to optimize the Bone Bandaid geometry (i.e., wire diameters and location). The results demonstrate that the proposed mechanism immobilizes the grafted bone in the locked state properly since the maximum resultant gap (21.54 micron) between the graft and host mandible surfaces are in the safe region (less than 300 micron). By considering the von Mises criteria for failure, FE analysis together with experimental studies (i.e., compressive and tensile testing on the inferior and superior fixation devices, respectively) confirm that the proposed fixation devices do not fail, showing safety factor of at least 10.3. Based on the Response Surface Methodology (RSM) technique, the optimal parameter values for the wires are achieved (0.65 mm and 1 mm for the superior and inferior wires, respectively) and the required level of preload on each wire are calculated (369.8 N and 229 N for the inferior and superior wires, respectively). The FE results for stress distribution on the reconstructed mandible during the released state closely match that of a healthy mandible.

Multi-Elemental Profiling of Tibial and Maxillary Trabecular Bone in Ovariectomised Rats

Atomic minerals are the smallest components of bone and the content of Ca, being the most abundant mineral in bone, correlates strongly with the risk of osteoporosis. Postmenopausal women have a far greater risk of suffering from OP due to low Ca concentrations in their bones and this is associated with low bone mass and higher bone fracture rates. However, bone strength is determined not only by Ca level, but also a number of metallic and non-metallic elements in bone. Thus, in this study, the difference of metallic and non-metallic elements in ovariectomy-induced osteoporosis tibial and maxillary trabecular bone was investigated in comparison with sham operated normal bone by laser ablation inductively-coupled plasma mass spectrometry using a rat model. The results demonstrated that the average concentrations of ²⁵Mg, ²⁸Si, ³⁹K, ⁴⁷Ti, ⁵⁶Fe, ⁵⁹Co, ⁷⁷Se, ⁸⁸Sr, ¹³⁷Ba, and ²⁰⁸Pb were generally higher in tibia than those in maxilla. Compared with the sham group, Ovariectomy induced more significant changes of these elements in tibia than maxilla, indicating tibial trabecular bones are more sensitive to changes of circulating estrogen. In addition, the concentrations of ²⁸Si, ⁷⁷Se, ²⁰⁸Pb, and Ca/P ratios were higher in tibia and maxilla in ovariectomised rats than those in normal bone at all time-points. The present study indicates that ovariectomy could significantly impact the element distribution and concentrations between tibia and maxilla.

Determination of a critical size calvarial defect in senile osteoporotic mice model based on in vivo micro-computed tomography and histological evaluation

PURPOSE

To evaluate differences in the spontaneous healing capacity of senescence-prone inbred strains (SAMP6) and senescence-resistant inbred strains (SAMR1) and determine the critical defect size in a mouse model of senescence-accelerated osteoporosis.

METHODS

Unilateral full-thickness calvarial defects 2 or 4mm in diameter were made in 6-month-old male SAMP6 and SAMR1. Defects were evaluated in vivo by micro-CT at day 0 and 6 and 12 weeks postoperatively. Calvarial specimens were harvested at 12 weeks for hematoxylin and eosin staining, Masson's trichrome staining, and tartrate-resistant-acid-phosphatase (TRAP) staining.

RESULTS

Less new bone was observed in defects in SAMP6 compared to SAMR1 at 12 weeks postsurgery, with <5% healing in SAMP6 for both 2- and 4-mm defects compared to >5% healing in 2-mm defects in SAMRI (P<0.05). Histological analysis revealed dense connective tissue but little bone healing in 2- and 4-mm defects in SAMP6 and 4-mm defects in SAMR1. New bone was observed at the periphery of the 2-mm defects in SAMR1. Masson's trichrome staining also supported these findings. No obvious TRAP-positive cells were observed at the defect margins, but SAMP6 exhibited greater osteoclast numbers and surface areas in the diploë of contralateral bone compared to smaller osteoblast numbers and surface areas at the defect sites in SAMR1.

CONCLUSIONS

Defects of 2mm or larger in the cranium was critical-size or nonhealing defects in both SAMP6 and SAMR1. The differential findings on micro-CT and histomorphometry for the calvarial defect sites between SAMP6 and SAMR1 may imply different regenerative abilities of intramembranous ossification in these two strains.

Effect of direct loading of phytoestrogens into the calcium phosphate scaffold on osteoporotic bone tissue regeneration

3D porous calcium deficient hydroxyapatite scaffolds with phytoestrogens were fabricated for osteoporotic bone tissue regeneration through a combination of 3D printing techniques and cement chemistry as a room temperature process.

Estrogen Deficiency-Associated Bone Loss in the Maxilla: A Methodology to Quantify the Changes in the Maxillary Intra-radicular Alveolar Bone in an Ovariectomized Rat Osteoporosis Model

The effects of estrogen deficiency on bone characteristics are site-dependent, with the most commonly studied sites being appendicular long bones (proximal femur and tibia) and axial bones (vertebra). The effect on the maxillary and mandibular bones is still inconsistent and requires further investigation. This study was designed to evaluate bone quality in the posterior maxilla of ovariectomized rats to validate this site as an appropriate model to study the effect of osteoporotic changes. Forty-eight 3-month-old female Sprague-Dawley rats were randomly divided into two groups: an ovariectomized (OVX) group (n=24) and Sham-operated (SHAM) group (n=24). Six rats were randomly sacrificed from both groups at time points 8, 12, 16, and 20 weeks. The samples from tibia and maxilla were collected for micro computed tomography (μCT) and histological analysis. For the maxilla, the volume of interest area focused on the furcation areas of the first and second molar. Trabecular bone volume fraction (BV/TV, %), trabecular thickness (Tb.Th.), trabecular number (Tb.N.), trabecular separation (Tb.Sp.), and connectivity density (Conn.Dens) were analyzed after Micro CT scanning. At 8 weeks the indices BV/TV, Tb.Sp., Tb.N., and Conn.Dens showed significant differences (p<0.05) between the OVX and SHAM groups in the tibia. Compared with the tibia, the maxilla developed osteoporosis at a later stage, with significant changes in maxillary bone density only occurring after 12 weeks. Compared with the SHAM group, both the first and second molars of the OVX group showed significantly decreased BV/TV values from 12 weeks, and these changes were sustained through 16 and 20 weeks. For Tb.Sp., there were significant increases in bone values for the OVX group compared with the SHAM group at 12, 16, and 20 weeks. Histological changes were highly consistent with Micro CT results. This study established a method to quantify the changes of intra-radicular alveolar bone in the posterior maxilla in an accepted rat osteoporosis model. The degree of the osteoporotic changes to trabecular bone architecture is site-dependent and at least 3 months are required for the osteoporotic effects to be apparent in the posterior maxilla following rat OVX.

Qualitative and quantitative evaluation of bony structures based on DICOM dataset

PURPOSE

The aim of this study was to investigate bone mass using different cone-beam computed tomographies (CBCTs) combined with image analysis and to determine whether bone quantity or quality was detected.

MATERIALS AND METHODS

Different measurements recorded on mandible bones of pigs in the retromolar region were evaluated on ProMax 3D (Planmeca Oy, Finland) and the ILUMA™CT (IMTEC™ Imaging, Ardmore, OK) to calculate a calibration curve. The spatial relationships of pig mandible halves relative to adjacent defined anatomical structures were assessed by means of 3D visualization software. In addition to the screenshot, their bone quality was evaluated in accordance with the Lenkholm and Zarb classification.

RESULTS

The CBCT calibration curves based on the measurements taken from the ProMax and ILUMA CT showed linear correlation. Huge Hounsfield units intervals were found between the 2 CBCTs and there was no correlation with the computed tomography. Exact information on the micromorphology of the bone cylinders was not available. A subjective correlation according to Lenkholm and Zarb showed overlapping in all groups.

CONCLUSIONS

CBCT is a good choice for analyzing bone mass. However, it does not provide any information on bone quality. To obtain information on the microarchitecture of the spongiosa, it is necessary to use a computed tomography with finite element analysis.

Osteopenia in the maxillofacial area: a study in sheep

Osteoporosis is a major public health problem worldwide. Its significance in the fields of traumatology and implantology of the maxillofacial area requires investigation. A large animal model was used to assess bone loss in the lumbar spine and mandible.

INTRODUCTION

Osteoporosis is a prevalent disease characterized by low bone mass and microarchitectural deterioration of bone tissue. Osteoporosis-related fractures represent a major public health burden. The presence and relevance of osteoporosis in the maxillofacial area remain controversial. Research in humans is limited by difficulties in finding large homogenous study groups and, due to ethical considerations, numerous animal models have been used in osteoporosis research. The aim of this study was to assess a sheep model of generalized osteopenia for changes in the maxillofacial area.

METHODS

Bone loss was induced in ten Merino sheep by ovariectomy, intramuscular administration of glucocorticoids, and a calcium-reduced diet. Five untreated animals served as controls. Bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry at the lumbar spine at baseline and after 1, 3, 6, 9, and 12 months. Lumbar and mandibular bone biopsies were obtained and analyzed with microcomputed tomography.

RESULTS

Lumbar BMD decreased progressively in the intervention group and was most significantly low after 6 months (p < 0.001). Lumbar trabecular bone showed a significant decrease in bone volume (BV)/tissue volume (TV; p < 0.05) in the inducted group. Significant changes were found in both analyzed mandibular regions for BV/TV (p < 0.05). Regional variations were found for other parameters in the mandible. The cortical width was substantially reduced in the intervention group (p < 0.001).

CONCLUSIONS

Microstructural changes occurring in sheep as a result of induction seem to have a generalized nature. This sheep model meets the criteria for further investigation in the maxillofacial area.

Effects of osteoporosis on AIS 3+ injury risk in motor-vehicle crashes

Older occupants in motor-vehicle crashes are more likely to experience injury than younger occupants. One possible reason for this is that increasing age is associated with increased prevalence of osteoporosis, which decreases bone strength. Crash-injury data were used with Bayes' Theorem to estimate the conditional probability of AIS 3+ skeletal injury given that an occupant is osteoporotic for the injury to the head, spine, thorax, lower extremities, and upper extremities. This requires the conditional probabilities of osteoporosis given AIS 3+ injury for each of the body regions, which were determined from analysis of the Crash Injury Research and Engineering Network database. It also requires information on probability of osteoporosis in the crash-involved population and the probabilities of AIS 3+ skeletal injury to different body regions in crashes. The latter probabilities were obtained from the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) database. The former was obtained by modeling the probability of osteoporosis in the US populations using data from the 2006 National Health Examination Nutrition Survey and applying this model to the estimate of the crash-involved population in NASS-CDS. To attempt to account for the effects of age on injury outcome that are independent of osteoporosis, only data from occupants who were 60 years of age or older were used in all analyses. Results indicate that the only body region that experiences a statistically significant change in fracture injury risk with osteoporosis is the spine, for which osteoporosis increases the risk of AIS 3+ fracture by 3.28 times, or from 0.41% to 1.34% (p<0.0001). This finding suggests that the increase in AIS 3+ injury risk with age for non-spine injuries is likely influenced by factors other than osteoporosis.

Morphometric analysis - Cone beam computed tomography to predict bone quality and quantity

AIM

Modified quantitative computed tomography is a method used to predict bone quality and quantify the bone mass of the jaw. The aim of this study was to determine whether bone quantity or quality was detected by cone beam computed tomography (CBCT) combined with image analysis. MATERIALS AND PROCEDURES: Different measurements recorded on two phantoms (Siemens phantom, Comac phantom) were evaluated on images taken with the Somatom VolumeZoom (Siemens Medical Solutions, Erlangen, Germany) and the NewTom 9000 (NIM s.r.l., Verona, Italy) in order to calculate a calibration curve. The spatial relationships of six sample cylinders and the repositioning from four pig skull halves relative to adjacent defined anatomical structures were assessed by means of three-dimensional visualization software.

RESULTS

The calibration curves for computer tomography (CT) and cone beam computer tomography (CBCT) using the Siemens phantom showed linear correlation in both modalities between the Hounsfield Units (HU) and bone morphology. A correction factor for CBCT was calculated. Exact information about the micromorphology of the bone cylinders was only available using of micro computer tomography.

CONCLUSION

Cone-beam computer tomography is a suitable choice for analysing bone mass, but, it does not give any information about bone quality.

Assessment of the risk of perforation of the mandibular canal by implant drill using density and thickness parameters

OBJECTIVE

The objective of this study was to investigate whether the resistance of the bone surrounding the mandibular canal had sufficient density and thickness to avoid perforation by drills when preparing the bed of the implant.

BACKGROUND

 Damage to the inferior alveolar nerve (IAN) is more common than expected. This injury may lead to serious complications ranging from mild paresthesia to total anaesthesia of the lower jaw.

MATERIALS AND METHODS

  The CT images of 99 patients, whose ages ranged between 20 and 79years, and who applied for an implant application to the posterior aspect of the mandible were included in this study.

RESULTS

The overall average bone thickness in the premolar and molar regions was 0.8717±0.1818 and 0.8556±0.1756mm, respectively, whereas the bone density in the premolar and molar regions was 649.18±241.42 and 584.44±222.73 Hounsfield Units (HU), respectively (p<0.001).

CONCLUSION

It was determined that the average density and thickness of the bone that surrounds the mandibular canal was not sufficient to resist the implant drill. It can be concluded that the risk of injury to the IAN may be minimised by accurately determining the bone mass on the canal prior to the implant procedure, and avoiding excessive force when approaching the canal.

Using vital statistics to estimate the population-level impact of osteoporotic fractures on mortality based on death certificates, with an application to France (2000-2004)

Background

We developed a methodology using vital statistics to estimate the impact of osteoporotic fractures on the mortality of an entire population, and applied it to France for the period 2000-2004.

Methods

Current definitions of osteoporotic fractures were reviewed and their components identified. We used the International Classification of Diseases with national vital statistics data for the French adult population and performed cross-classifications between various components: age, sex, I-code (site) and E-code (mechanism of fracture). This methodology allowed identification of appropriate thresholds and categorization for each pertinent component.

Results

2,625,743 death certificates were analyzed, 2.2% of which carried a mention of fracture. Hip fractures represented 55% of all deaths from fracture. Both sexes showed a similar pattern of mortality rates for all fracture sites, the rate increased with age from the age of 70 years. The E-high-energy code (present in 12% of death certificates with fractures) was found to be useful to rule-out non-osteoporotic fractures, and to correct the overestimation of mortality rates. Using this methodology, the crude number of deaths associated with fractures was estimated to be 57,753 and the number associated with osteoporotic fractures 46,849 (1.85% and 1.78% of all deaths, respectively).

Conclusion

Osteoporotic fractures have a significant impact on overall population mortality.

Comparison of implant survival with implants placed in acceptable and compromised bone: a literature review

BACKGROUND

Survival rates for conventional dental implant systems are relatively high in normal healthy bone. However, there are subgroups of patients that are at an increased risk of implant failure. In particular, patients with compromised quantity or quality of bone present a significant challenge to the dental implantologist.

OBJECTIVE

To perform a review of the literature in an attempt to quantify the relative risk of implant failure in compromised bone compared to good or acceptable bone and to identify whether certain anatomical regions are at greater risk.

SEARCH STRATEGY

We conducted a systematic electronic database search of Medline, Cinhahl and the Cochrane Library through March 2006 identifying articles meeting the eligibility criteria.

RESULTS

We calculated an increased risk of implant failure in compromised bone compared to healthy bone in both the maxilla and the mandible using conventional dental implant systems. Relative risks ranged from 2 to 12 with the highest risk of failure in the maxilla. Conventional systems are often used in combination or after bone augmentation procedures or more innovative methods for stimulating bone growth in patients with compromised bone. These approaches do have their limitations including high costs, the accumulation of the surgical risks, and delayed time to loading.

DISCUSSION

Quantifying the risk of implant failure in patients with compromised bone should assist the implantologist in treatment decision making and patient counseling. Alternative methods for treating patients with compromised bone include zygomatic and lateral implants, neither of which typically require bone augmentation procedures. More studies are needed to evaluate their safety and efficacy.

SEM analysis of dental enamel morphological structures on the basis of their replicas in patients with systemic calcium deficiency

The aim of the present study is to examine microscopically the surface of dental enamel by using a scanning electron microscope (SEM), using their replicas formed in female patients with diagnosed periodontal diseases and systemic calcium deficiency. Replicas of dental enamel surfaces in patients referred for treatment of periodontal diseases were subjected to microscopic analysis. The replicas, after coating with platinum-palladium alloy, were examined under the scanning electron microscope at magnifications of 15–5000 x. Densitometric examinations of spine (L2 - L4 segment) revealed bone mineral density BMD T-score lower than −2.5 in 5 patients, in the range of −1.5 to −2.5 in 10 patients, and higher than −1.5 in the remaining patients. Non-homogenous images of surfaces in the form of light and dark areas were observed. Light areas corresponded to damaged surfaces of dental tissues. Patients with higher systemic calcium deficiency had areas lighter in color. More of these areas were found in patients with higher systemic calcium deficiency. It can be assumed that the calcium deficit is likely to appear in the selected dental tissues, particularly in the dental enamel.

Automated osteoporosis risk assessment by dentists: a new pathway to diagnosis

General dental practitioners use a vast amount of panoramic radiography in their routine clinical work, but valuable information about patients' osteoporotic status is not collected. There are many reasons for this, but one of the prime reasons must be the disruption involved in clinical routine with lengthy manual radiographic assessment. We have developed computer software, based on active shape modeling that will automatically detect the mandibular cortex on panoramic radiographs, and then measure its width. Automatic or semi-automatic measurement of the cortical width will indicate the osteoporotic risk of the patient. The aim of our work was to assess the computer search technique's ability to measure the mandibular cortical width and to assess its potential for detection of osteoporosis of the hip, spine and femoral neck. Mandibular cortical width was measured using the manually initialized (semi-automatic) method and, when assessed for diagnosing osteoporosis at one of the three measurement sites, gave an area under the ROC curve (A(z))=0.816 (95% CI=0.784 to 0.845) and for the automatically initialized searches, A(z)=0.759 (95% CI=0.724 to 0.791). The difference between areas=0.057 (95% Confidence interval=0.025 to 0.089), p<0.0001. For diagnosing osteoporosis at the femoral neck, mandibular cortical width derived from the manually initialized fit gave an area under the ROC curve (A(z))=0.835 (95% CI=0.805 to 0.863) and for the automatically initialized searches A(z)=0.805 (95% CI=0.773 to 0.835). The difference in A(z) values between active shape modeling search methods=0.030 (95% CI=-0.010 to 0.070), and this was not significant, p=0.138. We concluded that measurement of mandibular cortical width using active shape modeling is capable of diagnosing skeletal osteoporosis with good diagnostic ability and repeatability.