The impact of primary hyperparathyroidism on the oral cavity

Dynamic morphometric changes in the mandibular osteocytic lacunae of ovariectomized rats in response to teriparatide, as revealed by three-dimensional fluorescence analyses: Possible involvement of osteocytic perilacunar remodeling

OBJECTIVES

Teriparatide [TPTD; human parathyroid hormone (hPTH1-34)] is an anti-osteoporotic drug with bone anabolic effects. Clinical and preclinical studies have indicated that TPTD has value in oral and maxillofacial bone therapies, including jawbone regeneration, periodontal tissue repair, and the treatment of medication-related osteonecrosis of the jaw. However, it is unclear whether the craniofacial bones respond to TPTD similarly to the axial and appendicular bones. Recent studies showed that TPTD acts on both osteocytes and osteoblasts. This study aimed to characterize distinct craniofacial bone sites, with a focus on morphometric changes in osteocytic lacunae in ovariectomized rats receiving TPTD.

METHODS

Conventional bone histomorphometric analyses of mandibular and parietal bone sections were conducted. High-resolution confocal imaging-based three-dimensional fluorescence morphometric analyses of osteocytic lacunae in distinct mandibular and parietal bone sites were conducted.

RESULTS

We observed dynamic changes in the morphometric characteristics of osteocytic lacunae specifically in alveolar and other mandibular bone sites upon TPTD administration.

CONCLUSIONS

These findings suggest that osteocytes in mandibular bone (specifically, alveolar bone) have unique functional characteristics of osteocytic perilacunar remodeling.

Epileptic seizures and abnormal tooth development as primary presentation of pseudohypoparathyroidism type 1B

Pseudohypoparathyroidism (PHP) is a rare genetic disorder characterised by a non-functioning PTH. Usually, the diagnosis is made following (symptomatic) hypocalcaemia. We describe a case in which epileptic seizures and abnormalities in dental development were the main clinical manifestation of PHP type 1B. This case demonstrates the importance of screening for hypocalcaemia in patients with de novo epileptic seizures. In addition, antiepileptic medications themselves may interfere with calcium-phosphate metabolism, causing or aggravating a hypocalcaemia as well. By correcting the calcium level, a resolution of these symptoms could be obtained.

Evaluation of osseous changes in dental panoramic radiography using radiomorphometric indices in patients with hyperthyroidism

OBJECTIVE

The aim of the present study was to compare radiomorphometric measurements on panoramic images of patients with hyperthyroidism (HT) to those of a control population.

STUDY DESIGN

In this retrospective study, the mental index (MI), inferior panoramic mandibular index (PMI), antegonial index (AI), gonial index (GI), and mandibular cortical index (MCI) were evaluated on dental panoramic radiographs (DPRs) of 40 patients with HT and 40 healthy age- and sex-matched individuals and compared between the groups. Quantitative data (MI, PMI, AI, and GI) were analyzed with the Student t and Mann-Whitney U tests. Categorical data (MCI) were analyzed with the chi-square test.

RESULTS

Statistically significant differences between the patient and control groups were found for inferior PMI (P = .001) and AI (P = .017) values, with smaller mean values among the patients. However, the measurements of MI (P = .59) and GI (P = .164) and the MCI distribution (P = .13) were similar in both groups.

CONCLUSIONS

Evaluating the radiomorphometric indices of inferior PMI and AI on the DPRs of patients with HT who are at high risk of secondary osteoporosis could be helpful in the early diagnosis of osteoporotic changes and in formulating surgical treatment plans.

Torus Mandibularis in Patients Receiving Hemodialysis

Reports on the prevalence of torus mandibularis among dialysis patients have been limited and inconclusive. A wide variety of oral manifestations has been found in patients with hyperparathyroidism. Furthermore, uremia-related changes in facial bone structures have been described in the literature. This prospective observational study examined 322 hemodialysis patients treated at the Chang Gung Memorial Hospital from 1 August to 31 December 2016. Two subgroups were identified: patients with torus mandibularis (n = 25) and those without (n = 297). Clinical oral examinations including inspection and palpation were employed. Our study found that most mandibular tori were symmetric (84.0%), nodular (96.0%), less than 2 cm in size (96.0%), and located in the premolar area (92.0%). Poor oral hygiene was observed among these patients, with 49.7% and 24.5% scoring 3 and 4, respectively, on the Quigley-Hein plaque index. More than half (55.0%) of patients lost their first molars. Multivariate logistic regression analysis revealed that blood phosphate level (odds ratio = 1.494, p = 0.029) and younger age (odds ratio = 0.954, p = 0.009) correlated significantly with torus mandibularis. The prevalence of torus mandibularis in patients receiving hemodialysis in this study was 7.8%. Younger age and a higher blood phosphate level were predictors for torus mandibularis in these patients.

Genome-wide family-based study in torus palatinus affected individuals

OBJECTIVE

Tori or exostoses are bony growths that appear in different oral regions. Torus palatinus, more specifically, develop in the palate midline and can impair proper word pronunciation and hinder the fabrication and use of dentures. Even though a multifactorial inheritance model has been suggested for torus palatinus appearance, precise genetic factors involved in its etiology remain unclear. Hence, in this study we aimed to identify variants across the genome of individuals from 46 Filipino families that associate with torus palatinus.

DESIGN

All families were composed of fishermen or landless rural dwellers who provided blood samples for DNA extraction and genotyping. A total of 3519 single nucleotide polymorphisms (SNPs) were analyzed through a transmission disequilibrium test in individuals affected by torus palatinus and their unaffected family members.

RESULTS

Fourteen SNPs showed trends for associations to the level of p < .005 threshold and several others were nominally (p < .05) associated with torus palatinus. We highlight SNP rs6582285, which is located in the CAPS2 gene, being the C allele less transmitted than the T allele in our sample. The C allele of CAPS2 rs6582285 protects from having torus palatinus whereas the other associations found were linked to an increased risk of developing the condition.

CONCLUSIONS

Trends for associations were identified for several markers across the genome, supporting the hypothesis that torus palatinus has a multifactorial mode of inheritance. We hope that our study contributes to a better understanding of torus palatinus etiology and helps guide future research in examining genes for this often-overlooked condition in different populations.

Rare Genetic Disorders Affecting the Periodontal Supporting Tissues in Adolescence

In adolescents periodontal destruction may be the primary manifestation of an as yet unrecognized rare systemic disease, and it may be up to the periodontist to make the correct tentative diagnosis. Many genetic diseases that present with primary periodontal manifestations in adolescence affect immune function, sometimes with only mild or absent systemic features. They include periodontal Ehlers-Danlos syndrome (lack of attached gingiva, various connective tissue abnormalities), Papillon-Lefèvre syndrome (palmoplantar hyperkeratosis), and plasminogen deficiency (fibrin deposition within mucous membranes). Other immune disorders with severe periodontitis manifesting in adolescence are usually diagnosed in early childhood due to unmistakeable systemic features. They include Cohen syndrome (developmental disorder, truncal obesity, and microcephaly), Hermansky-Pudlak Syndrome (oculocutaneous albinism, bleeding diathesis, and other systemic manifestations), glycogen storage disease type 1b, and Chediak-Higashi syndrome (pyogenic infections, albinism, and neuropathy). The structural integrity of periodontal tissue is affected in genodermatoses such as Kindler syndrome, a type of epidermolysis bullosa. In primary hyperoxaluria, inflammatory periodontal destruction is associated with renal calculi. Breakdown of periodontal tissues independent of dental plaque biofilm-induced periodontitis is found in hypophosphatasia (highly variable skeletal hypomineralization) or isolated odontohypophosphatasia, hypophosphatemic rickets and primary hyperparathyroidism. Finally, alveolar osteolysis mimicking localized periodontitis may be due to neoplastic processes, e.g., in neurofibromatosis type 1 (typical skin features including café au lait macules and neurofibromas), Langerhans cell histiocytosis (locally destructive proliferation of bone marrow-derived immature myeloid dendritic cells), and Gorham-Stout disease (diffuse cystic angiomatosis of bone).

Comparison of dental and skeletal indices between patients under haemodialysis and peritoneal dialysis with healthy individuals in digital panoramic radiography

OBJECTIVE

The aim was to compare dental and skeletal indices in panoramic radiography between patients undergoing haemodialysis, peritoneal dialysis and age- and sex-matched control group.

METHODS

In this comparative cross-sectional study, quantitative Indices including Antegonial Index (AI), Mental Index (MI), Panoramic Mandibular Index (PMI) and qualitative indices including Mandibular Cortical Index (MCI) and Trabecular Pattern (TP) were evaluated in panoramic images of 32 haemodialysis patients, 14 patients under peritoneal dialysis and 52 healthy individuals. The images were also investigated for pulp canal calcification, pulp stones, soft tissue calcification, changes in or loss of lamina dura, radiolucencies associated with brown tumour and ridge resorption. The indices were compared between the three groups and were investigated for association with the patients' blood test parameters and their diseases causing chronic renal failure (CRF). Intraobserver agreement for the 2-week interval of assessment was calculated for the indices.

RESULTS

MI (p = 0.574) and PMI (p = 0.100) were not significantly different, but AI (p = 0.01), MCI (p < 0.001) and TP (p = 0.002) were significantly different between the two case groups and the control group. The prevalence of pulp calcification (p = 0.03) and ridge resorption (p = 0.005) was higher in the haemodialysis group. Soft tissue calcification (p = 0.85) and lamina dura changes (p = 0.9) showed no significant difference. Brown tumours were observed in only one case in the haemodialysis group.

CONCLUSIONS

AI, MCI and TP showed a reduction in mineral density of the cortical and trabecular bone in CRF patients and more severely in patients under haemodialysis than those under peritoneal dialysis.

Parathyroidectomy Resolves Tooth Discoloration: A New Presenting Sign of Hyperparathyroidism?

Introduction

We report the resolution of tooth discoloration following parathyroidectomy in an otherwise asymptomatic woman with primary hyperparathyroidism-associated hypercalcemia. Case Report. A 59-year-old Caucasian woman, diagnosed with primary hyperparathyroidism in 2011, nonsmoker with excellent overall oral health. She complained of tooth discoloration starting in 2013. Pigmentation was particularly evident in the necks of the lower central and lateral incisors (Vita Classical score C2). No bleaching was undertaken. Parathyroidectomy was performed five years after primary hyperparathyroidism diagnosis. Six months later, a reduction in pigmentation was strikingly evident, with incisors scoring A1 and A2. The improvement persisted over time. Tooth value also increased compared to baseline.

Conclusions

This is, to our knowledge, the first report that parathyroidectomy might resolve dental discoloration. This outcome deserves investigation in a meaningful sample size and may eventually prompt the inclusion of dental issues among the consequences of primary hyperparathyroidism.

Torus Palatinus in Taiwan Patients Receiving Peritoneal Dialysis and Hemodialysis: A Prospective Observational Study

Purpose

A consensus about the pathogenesis of torus palatinus (TP) in patients receiving dialysis still eludes the scientific community. This prospective observational study investigated the epidemiology of TP in peritoneal dialysis and hemodialysis patients and analyzed the influences of multiple pathogenic factors such as mineral and bone disorders, genetic, environmental or nutritional triggers, progression of age, heredity, climatologic or biomechanical causes, and hyperparathyroidism on the formation of TP.

Methods

Between 2013 and 2016, a total of 575 chronic dialysis patients (441 on hemodialysis and 134 on peritoneal dialysis) were recruited from Chang Gung Memorial Hospital, Taiwan. Patients were stratified into two groups based on the presence (n = 179) or absence (n = 396) of TP. Demographic, oral examination, laboratory, and dialysis data were collected for analysis. Student’s t-test was used to analyze the quantitative variables and Chi-square or Fisher’s exact test for categorical variables. Univariate binary logistic regression analysis was conducted to determine the predictors for TP and multivariate binary logistic regression analysis to identify significant associated factors.

Results

The prevalence of TP in dialysis patients in this study was 31.1% (28.3% for hemodialysis and 40.3% for peritoneal dialysis). Patients with TP were younger (54.6 ± 13.4 versus 58.9 ± 14.7 years, P = 0.001) and mostly female (60.3 versus 41.2%, P < 0.001). Most TP cases (55.3%) were small in size (<2 cm), with the flat shape (56.4%) being the most common followed by the spindle (17.9%), nodular (17.3%), and lobular (8.4%) shapes. A longer duration of dialysis was associated with TP ≥2 cm than with TP <2 cm (94.4 ± 85.9 versus 72.8 ± 59.1 months, P = 0.048). Multivariate logistic regression revealed that female gender (odds ratio 2.108, 95% confidence interval 1.455–3.055, P < 0.001) and younger age (odds ratio 0.982; 95% confidence interval 0.969–0.994, P = 0.005) were significant predictors for TP.

Conclusion

The prevalence of TP in chronic dialysis patients is 31.1%, higher in patients receiving peritoneal dialysis (40.3%) than hemodialysis (28.3%). Female gender and younger age are significant predictors associated with TP.

Mandibular cortical indices and their relation to gender and age in the cone-beam computed tomography

OBJECTIVES

The purpose of this study is to evaluate normal ranges of cortical bone Hounsfield units indices through cone beam CT images, and to investigate their relationships with age and sex.

METHODS

700 adult human cone beam CT images were evaluated retrospectively, and divided into 4 age groups. Six different cortical bone Hounsfield unit measurements were applied bilaterally, where gender and age were recorded. Collected data were subjected to statistical analysis and ANOVA tests were used for various comparisons.

RESULTS

The cortical bone measurements between female and male patients were significantly different (p<0.05). Cortical bone thickness indices showed greater values in male patients compare to female patients (p<0.05). Quantitative mandibular indices were significantly lower in first age group (18-30 years) than other three older age groups (p<0.01).

CONCLUSION

The results of this study seems to propose a persistent alteration in the mandibular cortical bone with age and that this influced by sex. Further studies with larger patient groups are needed to clarify and understand these mandibular indices.

Factors affecting decision making at reassessment of periodontitis. Part 2: interpretation of clinical findings - systemic factors

This paper is the second in a four-part series outlining treatment planning at periodontal reassessment. The first article focussed on the information that should be gathered at the reassessment appointment. Treatment can involve a range of non-surgical and surgical approaches. A variety of general, practical and local site factors can affect the choice of one option over another in choosing the most predictable treatment option. Residual periodontal probing depths can be associated with both systemic and local factors. This article (part 2) outlines systemic factors that need to be assessed when faced with residual periodontal probing depths.

Persistence of "non-dipping" pattern in blood pressure after curative parathyroidectomy in apparently normotensive patients with symptomatic primary hyperparathyroidism

BACKGROUND

The prevalence of hypertension in primary hyperparathyroidism (PHPT) varies from 20-80% with data being based on office-based blood pressure measurements. Little is known about ambulatory monitoring of blood pressure (AMBP) in PHPT and changes in blood pressure (BP) variables post-curative parathyroidectomy. Hence, we conducted a prospective study wherein we performed AMBP in apparently normotensive patients with PHPT and reevaluated them 3 months post-curative parathyroidectomy.

METHODS

Consecutive patients with symptomatic PHPT aged 20 years and above underwent 24 hours AMBP at enrollment and at 3 months after successful parathyroidectomy. Pre- and postoperative BP variables were compared and correlated with serum calcium, creatinine and intact parathyroid hormone (iPTH) levels.

RESULTS

After exclusion, 17 symptomatic PHPT patients were enrolled in the study. AMBP detected hypertension in 4 (23.5%) patients. There was a significant reduction in the average nighttime systolic (P=0.007) and diastolic BP (P=0.034) after parathyroidectomy. However, the average 24 hours systolic/diastolic BP, daytime systolic/diastolic BP and average 24 hours mean arterial pressure did not differ before and after surgery. Non-dipping blood pressure pattern was seen in 53% of patients at presentation and persisted in 50% of cases after successful surgery. None of the biochemical parameters significantly correlated with any BP variable.

CONCLUSIONS

AMBP can help detect hypertension in patients with PHPT that remains unrecognized with routine office-based blood pressure measurement. In addition, AMBP detects loss of normal dipping pattern in BP that persists in almost half of the patients even after successful parathyroidectomy, perhaps because of permanent vascular damage induced by PHPT.

Manifestations of systemic diseases and conditions that affect the periodontal attachment apparatus: Case definitions and diagnostic considerations

OBJECTIVES

This review proposes case definitions and diagnostic considerations of systemic disorders and conditions that affect the periodontal attachment apparatus.

IMPORTANCE

Periodontal diseases and certain systemic disorders share similar genetic and/or environmental etiological factors, and affected patients may show manifestations of both diseases. Characterizing these diseases and the nature of the association between them could have important diagnostic value and therapeutic implications for patients.

FINDINGS

Numerous systemic disorders and certain medications can affect the periodontal attachment apparatus and cause loss of periodontal attachment and alveolar bone. Although many of these disorders are rare or uncommon, they often cause significant loss of periodontal tissue by influencing periodontal inflammation or through mechanisms distinct from periodontitis. Most of these disorders are due to innate mechanisms and some are acquired via environmental factors or lifestyle. Several disorders affect periodontal inflammation through alterations in the host immune response to periodontal infection; others cause defects in the gingiva or periodontal connective tissue, instigate metabolic changes in the host that affect various tissues of the periodontal apparatus, or operate by other mechanisms. For some systemic disorders that are more common, their contribution to the loss of periodontal tissue is modest, while for others, contribution is not supported by clear evidence. Few systemic medications are associated with increased loss of periodontal tissue, and these are typically medications used in the treatment of malignancies.

CONCLUSIONS

This review identifies systemic diseases and conditions that can affect the periodontal attachment apparatus and cause loss of periodontal supporting tissues and, where possible, presents case definitions for these. Many of these diseases are associated with a profound loss of periodontal attachment and alveolar bone, and for some of these disorders the periodontal manifestations may be among the first signs of the disease. These case definitions may be useful in the early diagnosis of these diseases and may contribute to an improvement in the management of periodontal manifestations and improve the quality of life for these patients.

Images in medicine: torus palatinus

A 56 year old African-American female with history of well-controlled hypertension and hyperlipidemia presented to the office for an annual physical examination. She did not have any complaints. She reported being compliant with her medications, exercised daily at her local gym, and maintained a low salt diet. She visits her dentist every 6 months and has had a few fillings in her premolars in the past. On physical examination, her vital signs were normal and the entirety of her physical examination was normal with the exception of her oropharynx. Throat examination revealed a 2 × 1 cm midline hard palate swelling that was bony hard in consistency and covered by normally appearing oral mucosa. It was diagnosed as a torus palatinus. The patient was unaware of its presence and denied being informed about it by her dentist on any visit. She was also educated about the diagnosis and safety-netted by being informed about red-flags that would prompt investigation such as change in size or shape.

Survey of Torus Palatinus in Patients with End-Stage Renal Disease Undergoing Hemodialysis

Introduction

This study attempted to survey the oral findings of hemodialysis patients and analyze the prevalence and predictors for torus palatinus (TP) in this patient population.

Methods

A total of 322 hemodialysis patients were recruited. Patients were organized into two groups, based on the presence (n=93) or absence (n=229) of TP. Demographic, laboratory, and dialysis-related data were obtained for analysis.

Results

The prevalence of TP was 28.9% in this study. Patients with TP were younger in age [57.8±10.0 (37.4-86.9) versus 62.4±12.3 (25.0-87.8) years old; P=0.001] and predominantly female (60.2% versus 38.0%; P<0.001), compared to patients without TP. All TPs (100.0%) were symmetrical and located along the midpalatal suture. Most TPs were flat-shaped (55.9%) and near premolars (78.5%). The blood tests revealed higher blood concentrations of phosphate (5.4±1.1 versus 4.9±1.1 mg/dL; P=0.001) and lower blood concentrations of bicarbonate (20.9±2.4 versus 22.0±2.3 mmol/L; P<0.001) in patients with TP. Multivariate regression modeling showed that younger age [odds ratio (OR) 0.968; 95% confidence interval (CI) 0.939–0.982; P<0.001], female gender (OR 2.305; 95% CI 1.374–3.867; P=0.002), higher blood concentration of phosphate (OR 1.411; 95% CI 1.110–1.794; P=0.005), and lower blood concentration of bicarbonate (OR 0.868; 95% CI 0.791–0.994; P=0.040) were significant predictors for TP.

Conclusion

The prevalence of TP is 28.9%, and the majority of patients suffering TP are female. Younger age, female gender, elevated blood concentration of phosphate, and lower blood concentration of bicarbonate are predictors for TP.

Secondary hyperparathyroidism causing increased jaw bone density and mandibular pain: a case report

We present the case of a 32-year-old male patient complaining of recurrent mandibular pain for 3.5 years. Panoramic radiography indicated increased cortical density of the mandibular lower border. Scintigraphy and single-photon emission computed tomography revealed metabolic hyperactivity in that region without pathologic lymph nodes. A bone biopsy specimen of the mandibular lower border did not have inflammation or cytologic atypia. Endocrinologic investigation confirmed secondary hyperparathyroidism as a result of hypovitaminosis D. Several weeks after starting therapy with oral vitamin D supplements, the symptoms completely disappeared. Increased cortical density is a rare manifestation of secondary hyperparathyroidism, which normally causes the lamina dura to vanish and produces a ground-glass appearance as a result of blurring of the trabecular bone pattern. Because focal hyperostosis can have multiple benign or malignant causes, radiologic examination of the jaw bones is indispensable for evaluating orofacial pain. Increased cortical density may be caused by metabolic diseases, requiring further investigations, including biopsy and blood analysis.

Radiographic Fractal and Clinical Resonance Frequency Analyses of Posterior Mandibular Dental Implants: Their Possible Association With Mandibular Cortical Index With 12-Month Follow-up

BACKGROUND

The aim of the present study was to investigate whether the mandibular cortical index (MCI) has a relationship with fractal dimension of bone and/or implant stability, and to justify the possible association between MCI, fractal dimension, and stability.

MATERIALS AND METHODS

Eighty-two subjects who received dental implants to replace missing mandibular premolar/molar sites were selected. Three months after surgical placement, implants were restored with fixed ceramic fused metal crowns. MCI was evaluated at baseline; fractal dimensions were measured with fractal analysis (FA) and implant stability quotient (ISQ) with resonance frequency analysis immediately after surgery and 12-month follow-up.

RESULTS

FA at mesial and distal regions for Class 1, Class 2, and Class 3 MCI resulted with significant increases at 12-month follow-up compared to baseline. The ISQ in patients with Class 2 and Class 3 MCI resulted with a significant decrease compared to Class 1 MCI at baseline and at 12 months. All MCI classes evaluated with ISQ and FA at baseline values resulted with significant increases at 12 months. Significant correlations were considered for all mandibular posterior implants between baseline and 12-month measurements for ISQ and FA evaluations.

CONCLUSIONS

Fractal analysis may be a useful method for understanding the healing process around implants and implant stability quotient values. Mandibular cortical index evaluations should be considered before implant procedures, which may provide a presurgical treatment plan and may provide information about the mandibular bone quality.

Oral Tori in Chronic Peritoneal Dialysis Patients

Background

The pathogenesis of oral tori has long been debated and is thought to be the product of both genetic and environmental factors, including occlusal forces. Another proposed mechanism for oral tori is the combination of biomechanical forces, particularly in the oral cavity, combined with cortical bone loss and trabecular expansion, as one might see in the early stages of primary hyperparathyroidism. This study investigated the epidemiology of torus palatinus (TP) and torus mandibularis (TM) in peritoneal dialysis patients, and analyzed the influences of hyperparathyroidism on the formation of oral tori.

Method

In total, 134 peritoneal dialysis patients were recruited between July 1 and December 31, 2015 for dental examinations for this study. Patients were categorized into two subgroups based on the presence or absence of oral tori. Demographic, hematological, biochemical, and dialysis-related data were obtained for analysis.

Results

The prevalence of oral tori in our sample group was high at 42.5% (57 of 134), and most patients with oral tori were female (61.4%). The most common location of tori was TP (80.7%), followed by TP and TM (14.0%), then TM (5.3%). All 54 TP cases were at the midline, and most were <2 cm (59.3%), flat (53.7%), and located in the premolar region (40.7%). Of the 11 TM cases, all were bilateral and symmetric, mostly <2 cm (81.9%), lobular (45.4%), and located at premolar region (63.6%). Interestingly, patients with oral tori had slightly lower serum levels of intact parathyroid hormones than those without oral tori, but the difference was not statistically significant (317.3±292.0 versus 430.1±492.6 pg/mL, P = 0.126). In addition, patients with oral tori did not differ from patients without tori in inflammatory variables such as serum high sensitivity C-reactive protein levels (6.6±8.2 versus 10.3±20.2 mg/L, P = 0.147) or nutritional variables such as serum albumin levels (3.79±0.38 versus 3.77±0.45 g/dL, P = 0.790). Furthermore, there were no differences between patients with and without oral tori in dialysis adequacy (weekly Kt/V_urea, 2.14±0.39 versus 2.11±0.33, P = 0.533; weekly creatinine clearance rate, 59.31±17.58 versus 58.57±13.20 L/1.73 m², P = 0.781), or peritoneal membrane transporter characteristics (P = 0.098).

Conclusion

Secondary hyperparathyroidism does not contribute to the formation of tori in peritoneal dialysis patients. Further studies are warranted.

Emerging regenerative approaches for periodontal reconstruction: a systematic review from the AAP Regeneration Workshop

More than 30 years have passed since the first successful application of regenerative therapy for treatment of periodontal diseases. Despite being feasible, periodontal regeneration still faces numerous challenges, and complete restoration of structure and function of the diseased periodontium is often considered an unpredictable task. This review highlights developing basic science and technologies for potential application to achieve reconstruction of the periodontium. A comprehensive search of the electronic bibliographic database PubMed was conducted to identify different emerging therapeutic approaches reported to influence either biologic pathways and/or tissues involved in periodontal regeneration. Each citation was assessed based on its abstract, and the full text of potentially eligible reports was retrieved. Based on the review of the full papers, their suitability for inclusion in this report was determined. In principle, only reports from scientifically well-designed studies that presented preclinical in vivo (animal studies) or clinical (human studies) evidence for successful periodontal regeneration were included. Hence, in vitro studies, namely those conducted in laboratories without any live animals, were excluded. In case of especially recent and relevant reviews with a narrow focus on specific regenerative approaches, they were identified as such, and thereby the option of referring to them to summarize the status of a specific approach, in addition to or instead of listing each separately, was preserved. Admittedly, the presence of subjectivity in the selection of studies to include in this overview cannot be excluded. However, it is believed that the contemporary approaches described in this review collectively represent the current efforts that have reported preclinical or clinical methods to successfully enhance regeneration of the periodontium. Today's challenges facing periodontal regenerative therapy continue to stimulate important research and clinical development, which, in turn, shapes the current concept of periodontal tissue engineering. Emerging technologies--such as stem cell therapy, bone anabolic agents, genetic approaches, and nanomaterials--also offer unique opportunities to enhance the predictability of current regenerative surgical approaches and inspire development of novel treatment strategies.

Changes in jawbones of male patients with chronic renal failure on digital panoramic radiographs

OBJECTIVE

To compare the existence of gonial cortical bone thickness, antegonial index, mandibular canal bone resorption and gonial angle values and pathologies like ground-glass appearance in jawbones and brown tumor in male patients undergoing dialysis due to chronic renal failure and men from the healthy control group on panoramic radiographs.

MATERIALS AND METHODS

Panoramic radiographs were taken from 80 male individuals in total (40 normal and 40 dialysis patients). Values obtained from the right and left sides of the mandible were summed and their means were calculated. Gonial cortical thickness, antegonial index and gonial angle values were assessed with the Student's t-test, mandibular canal wall resorption with the Chi-square test, and pathologies such as ground-glass appearance and Brown tumor as "available" or "not available."

RESULTS

Statistically significant differences were observed among the antegonial index (P < 0.001), gonial cortical bone thickness (P < 0.001), and gonial angle (P < 0.001) values of study and control groups. Besides, mandibular canal wall resorption (P < 0.001) was also statistically significant. In the study group, pathologies with ground-glass appearance were encountered in mandible, but no radiographic findings were observed similar to brown tumor.

CONCLUSIONS

Compared to the control group, decreases were found in gonial cortical bone thicknesses, antegonial index values, mandibular canal wall resorption, and gonial angle values of the patients receiving dialysis treatment due to chronic renal failure. Although it is not statistically significant, pathology with ground-glass appearance was detected in a patient, but no pathologies like brown tumor were observed. These findings from patients with chronic renal failure must be evaluated in panoramic radiography.

Botulinum toxin in masticatory muscles of the adult rat induces bone loss at the condyle and alveolar regions of the mandible associated with a bone proliferation at a muscle enthesis

In man, botulinum toxin type A (BTX) is injected in masticatory muscles for several indications such as trismus, bruxism, or masseter hypertrophy. Bone changes in the mandible following BTX injections in adult animal have therefore became a subject of interest. The aim of this study was to analyze condylar and alveolar bone changes following BTX unilateral injections in masseter and temporal muscles in adult rats. Mature male rats (n = 15) were randomized into 2 groups: control (CTRL; n = 6) and BTX group (n= 9). Rats of the BTX group received a single injection of BTX into right masseter and temporal muscles. Rats of the CTRL group were similarly injected with saline solution. Rats were sacrificed 4 weeks after injections. Masticatory muscles examination and microcomputed tomography (microCT) were performed. A significant difference of weight was found between the 2 groups at weeks 2, 3 and 4 (p < 0.05). Atrophy of the right masseter and temporal muscles was observed in all BTX rats. MicroCT analysis showed significant bone loss in the right alveolar and condylar areas in BTX rats. Decrease in bone volume reached -20% for right alveolar bone and -35% for right condylar bone. A hypertrophic bone metaplasia at the digastric muscle enthesis was found on every right hemimandible in the BTX group and none in the CTRL group. BTX injection in masticatory muscles leads to a significant and major mandible bone loss. These alterations can represent a risk factor for fractures in human. The occurrence of a hypertrophic bone metaplasia at the Mus Digastricus enthesis may constitute an etiological factor for tori.

Bimaxillary Full Arch Fixed Dental Implant Supported Treatment for a Patient With Renal Failure and Secondary Hyperparathyroidism and Osteodystrophy

A long-term dialysis patient with end-stage renal disease (ESRD) also referred to as chronic kidney disease (CKD) due to IgA nephropathy complicated by severe secondary hyperparathyroidism and renal osteodystrophy was successfully treated with dental implant-supported fixed prostheses. Phosphate binders, vitamin D, calcium cinacalcet calcimimetic therapy, and dialysis 3 times weekly had been instituted with standard divalent ion serum assessments. Successful control of the patient's secondary hyperparathyroidism was achieved. Long and wide diameter implants were used with an anterior guidance occlusion scheme to reduce the per-square-millimeter off-axial implant force delivered to the bone. Patients with ESRD and renal osteodystrophy may be successfully surgically and prosthetically treated with long wide dental implants supporting fixed full arch splinted dental prostheses with an appropriate occlusal scheme.

Giant Cell Lesions Associated with Primary Hyperparathyroidism

AIMS AND OBJECTIVE

To evaluate the prevalence, clinical features, diagnostic laboratory values and treatment outcome of giant cell lesions (brown tumors) associated with primary hyperparathyroidism (PHPT) in oral and maxillofacial region.

STUDY DESIGN

A 5 year retrospective data was analyzed wherein all histopathologically proven cases of giant cell lesions involving oral and maxillofacial region were evaluated. Out of these cases, those associated with PHPT were tabulated. Correlation was established with other concomitant clinical features and also with the laboratory values of altered serum calcium, phosphate, alkaline phosphate and parathormone. Follow up of these cases after the correction of PHPT was also noted.

RESULT

Out of 85 cases of histopathologically proven giant cell lesions, five cases were associated with PHPT. There was involvement of maxilla and mandible in one case each. Only frontal bone was involved in two cases. Fifth case had multiple lytic lesions in maxilla and frontal bone. All patients consistently showed very high values of alkaline phosphate and parathormone. Hypercalcemia and hypophosphatemia was noted in four cases. All cases showed regression of the lytic lesion after parathyroidectomy obviating the need for surgical excision of the jaw lesions.

CONCLUSION

Giant cell lesions (brown tumors) associated with PHPT in oral and maxillofacial region are rare clinical entities. The prevalence of PHPT associated giant cell lesions is 5.9 %. They are clinically, radiologically and histopathologically similar to any other peripheral or central giant cell tumor. Relevant history may alert the clinician and altered biochemical values may help in correlating the oral and maxillofacial findings with the underlying systemic disease. At times, the brown tumor maybe the only presenting sign leading to the diagnosis of PHPT.

Principles of endocrinology

The endocrine system plays a major role in human survival. Endocrine glands secrete chemical messengers or hormones that affect every tissue of the body, including the periodontium, during the life of the individual. As the endocrine system influences a broad assortment of biological activities necessary for life, a general understanding of the principal components and functions of this system is essential. A fundamental assessment of hormone structure, mechanism of action and hormone transport, as well as influence on homeostasis is reviewed. A concise evaluation of the functions of the central endocrine glands, the functions of the major peripheral endocrine glands (other than gonadal tissues) and the known relationships of these hormones to the periodontium is examined.

Enamel-renal-gingival syndrome and FAM20A mutations

The enamel-renal syndrome of amelogenesis imperfecta (AI) and nephrocalcinosis, and the amelogenesis imperfecta-gingival fibromatosis syndrome have both been associated with mutations in FAM20A. We report on two unrelated Thai patients with three novel and one previously reported mutations in FAM20A with findings suggesting both disorders, including hypoplastic AI, gingival fibromatosis, unerupted teeth, aggressive periodontitis, and nephrocalcinosis/nephrolithiasis. Additional findings consisted of a supernumerary premolar, localized aggressive periodontitis, thin alveolar bone, vitamin D deficiency-associated hyperparathyroidism, and heterotopic calcification in other tissues, including lungs, dental pulp, gingiva, dental follicles, and periodontal tissues, and early cessation of limited menstruation. Greater promotory activity of urine on calcium oxalate crystal growth compared to controls may help to explain the pathogenesis, and suggest that FAM20A mutations can contribute to nephrocalcinosis/nephrolithiasis. Our findings expand the phenotypic spectrum of FAM20A mutations. Since both of our patients and a large number of previously reported cases had all the important features of both syndromes, including AI, renal anomalies, and gingival fibromatosis, we are convinced that these two disorders actually are the same entity. The name of enamel-renal-gingival syndrome is suggested.

Parathyroid hormone applications in the craniofacial skeleton

Parathyroid hormone (PTH) is known for its ability to 'build' bone, with research in this area centered on its use as an osteoporosis therapeutic. Recent interest has developed regarding its potential for regenerative applications such as fracture healing and osseous defects of the oral cavity. Many years of investigation using murine gene-targeted models substantiate a role for signaling at the PTH/PTH-related protein (PTHrP) receptor (PPR) in intramembranous bone formation in the craniofacial region as well as in tooth development. Pre-clinical studies clearly support a positive role of intermittent PTH administration in craniofacial bones and in fracture healing and implant integration. A few human clinical studies have shown favorable responses with teriparatide (the biologically active fragment of PTH) administration. Favorable outcomes have emerged with teriparatide administration in patients with osteonecrosis of the jaw (ONJ). New delivery strategies are in development to optimize targeted application of PTH and to help maximize local approaches. The promising host-modulating potential of PTH requires more information to further its effectiveness for craniofacial regeneration and osseous wound-healing, including a better delineation of cellular targets, temporal effects of PTH action, and improved approaches for local/targeted delivery of PTH.

Glucocorticoids reduce alveolar and trabecular bone in mice

Glucocorticoid (GC) treatment is the main cause of secondary osteoporosis. There are some controversies about the relationships between alveolar bone loss and bone loss at the appendicular and axial skeleton.

OBJECTIVE

To assess, in parallel, the effects of GCs on alveolar bone and on the tibia in a mice model.

METHODS

Five-month-old male Swiss-Webster mice were randomized into two groups. Pellets releasing 5 mg/kg/day of prednisolone or control pellets were subcutaneously implanted for 28 days. After euthanasia, the right tibia and the right hemimandible of each mouse were analyzed by histomorphometry and microcomputed tomography. Alveolar bone consists of a thin slab between the incisor and the molar roots connected with the alveolar processes. A 2D-frontal section was done through the pulp chamber of the first molar and was used to measure the thickness of the alveolar bone slab. A 2D-sagittal section was done through the pulp chamber of the three molars and was used to measure bone volume in the alveolar processes.

RESULTS

At day 28, thickness and bone volume of alveolar bone were significantly decreased in the GC group (P<0.05). At the tibia, GCs decreased bone formation with a reduced mineral apposition rate and bone formation rate and a significant decrease in BV/TV and Tb.Th (P<0.05).

CONCLUSION

Although the amount of alveolar bone is very low in the mouse, this study shows that GCs can induce an alveolar bone loss in long-term treated animals.

Parathyroid hormone and its effects on dental tissues

In the current era, various pharmacological agents exist for osteoporosis management, and synthetic parathyroid hormone (PTH) (Teriparatide, Forteo) is one of the treatment options. Depending on the timing of administration, PTH has a unique ability to cause both bone apposition and bone resorption. This review focuses on the effects of PTH on the bone, specifically the jaw bones mandible and maxilla. The article briefly describes the fundamental mechanism of PTH action at the molecular level, as well as in experimental animals and in humans. It differentiates intermittent administration of PTH, especially at doses tolerated by humans that increase bone strength and prevent bone fractures, from continuous use that may lead to bone loss. In particular, it shows how intermittent administration of PTH can play a significant role in periodontal repair and implant success via stimulation of bone mineral content especially in the pre-alveolar region.

Dietary-induced hyperparathyroidism affects serum and gingival proinflammatory cytokine levels in rats

BACKGROUND

Poor diet and inadequate nutrition are suggested to affect the periodontium as well as impair the systemic health. This study investigated the systemic and periodontal effects of dietary-induced hyperparathyroidism (dHPT) by evaluating serum and gingival proinflammatory cytokine levels.

METHODS

Twenty-four Sprague-Dawley rats were used in the study. dHPT was induced in 12 rats by calcium/phosphorus imbalance, and 12 rats were fed a standard diet (SD). Afterward, endotoxin-induced periodontitis was induced on the right mandibular molar teeth (mmt). Four study groups were created: dHPT + mmt without periodontitis (group 1), dHPT + mmt with periodontitis (group 2), SD + mmt with periodontitis (group 3), and SD + mmt without periodontitis (group 4). Interleukin (IL)-1beta and tumor necrosis factor-alpha (TNF-alpha) levels were measured by enzyme-linked immunosorbent assay to evaluate the proinflammatory cytokine profiles. Serum cytokines were analyzed in the blood samples collected prior to periodontitis induction, whereas gingival cytokines were analyzed in the gingival supernatants of the four groups.

RESULTS

Serum cytokines were higher in dHPT rats than in SD rats (P <0.001), with a positive correlation between parathormone and the cytokines (P <0.001). Gingival cytokines were highest in group 2 and lowest in group 4 (group 2 > group 3 > group 1) (P <0.001). There was a positive correlation between parathormone and the gingival cytokines in group 1 (P <0.001 for IL-1beta; P <0.01 for TNF-alpha).

CONCLUSION

The results suggested that increased serum proinflammatory cytokine production may be a complication of dHPT, and this may affect healthy and diseased periodontia by increasing gingival proinflammatory cytokine levels.

Bone formation with disruption of the lamina dura in the mandibular third molar

The lamina dura is a healthy structural component in teeth. This study highlights the association of bone formation with disruption of lamina dura below the crown of the mandibular horizontal incompletely impacted third molar.

Age-related disruption of the lamina dura: evidence in the mandibular horizontal incompletely impacted third molar

Changes in the lamina dura are associated with dental diseases around the root of the tooth and with systemic diseases; however, the lamina dura below the crown of horizontal, incompletely impacted third molars has not been studied. Using orthopantomography, we studied the age of subjects with and without the lamina dura in 419 subjects. The participants were between the ages of 21 and 89 years. Mean age in men with the lamina dura was 30.29 ± 9.92 and without the lamina dura was 47.64 ± 16.32 (P < 0.0001), and in women with a lamina dura it was 29.65 ± 8.19 and without a lamina dura 41.97 ± 11.07 (P < 0.0001). To study the effect of aging, the relationship between the lamina dura and dental status was assessed in subjects over the age of 31 years. Alveolar bone resorption in the canine and the first molar of the ipsilateral mandible in subjects without the lamina dura was not significantly higher than in those with the lamina dura. There were no significant differences in the number of teeth lost, except in men, the number of treated teeth and the number of decayed teeth differed between groups. Disruption of the lamina dura was related to age, but with no alveolar bone resorption in the mandible.

Do gender and torus mandibularis affect mandibular cortical index? A cross-sectional study

Background

The interactions between torus and several factors such as age, gender, and dental status have not been studied comprehensively. The purpose of this study was to determine the effect of gender on the mandibular cortical index (MCI) and to investigate a possible association between torus mandibularis (TM) and MCI.

Methods

The study consisted of 189 consecutive patients referred to Department of Oral Diagnosis and Radiology of Hacettepe University within 30 workdays. Patients who did not have systemic disorders affecting bone density were included; and the age, gender, dental status and existing TM of the patients were recorded. Morphology of the mandibular inferior cortex was determined according to Klemitti's classification on panoramic radiographs.

Results

MCI was affected by age and gender (P < 0.05). No significant relationship was found between TM and MCI (P > 0.05).

Conclusion

In the study population, MCI was affected by age and gender. As age increased, semilunar defects could be seen on the cortex of the mandible and MCI values increased. Women appeared to have higher MCI values than men.