Histomorphometric analysis of age changes in the human inferior alveolar artery

Lingual Mandibular Bone Depression

BACKGROUND/AIM

In the area of the jaw angle, osteolytic lesions can occur, the differential diagnosis of which can be difficult and require very different therapeutic measures. One of these lesions is lingual mandibular bone depression (LMBD). The aim of this study was to present the characteristics of the lesion in a group of LMBD patients and to differentiate it from other lesions.

PATIENTS AND METHODS

Radiological images of 21 patients with LMBD were examined.

RESULTS

The majority of LMBDs were located in the jaw angle. On cross-sectional images, the lesion could be distinguished from salivary tissue (n=2). One case of LMBD had an impact on the course of the fracture line in the mandibular trauma.

CONCLUSION

LMBD is a developmental disorder of the mandible and only rarely of pathological importance. Imaging the lesion with cross-sectional images is preferable to using plain X-ray projections. In some cases, surgical exploration is essential for diagnosis.

Dental implant placement with inferior alveolar nerve repositioning in severely resorbed mandibles: a retrospective multicenter study of implant success and survival rates, and lower lip sensory disturbances

Background

The purpose of this study was to analyze medium-to-long-term implant success and survival rates, and lower lip sensory disturbance after placement of dental implants with simultaneous inferior alveolar nerve (IAN) repositioning.

Methods

Fifteen patients (3 men, 12 women) treated in two centers were included in this retrospective study. The ages of the participants ranged from 19 to 68. A total of 48 dental implants were placed in 23 posterior mandibular segments simultaneously with IAN transposition or lateralization. The residual bone above the IAN ranged from 0.5 to 7.0 mm. Crestal bone changes were measured using cone beam computed tomography (CBCT) images. Disturbance of the IAN was evaluated subjectively using a modified questionnaire.

Results

The healing process was uneventful in fourteen patients. In one patient, spontaneous fracture of the operated mandible occurred on tenth day after the surgery. The implant in the fracture line was removed at the time of open reduction and fixation. One more implant was lost after 5 years of loading. Therefore, the overall dental implant survival rate was 95.8%, whereas all implants in function were judged as successful after a follow-up period of 1 to 10 years. Transient neurosensory disturbances (ND) were observed in all patients who underwent IAN lateralization and IAN transposition. At follow-up times of 3 years, 5 years, and 10 years, weak hypoesthesia remained in two subjects treated with IAN transposition. None of the patients developed neuropathic pain after the procedure.

Conclusions

Within the limitations of this study, we conclude that reconstruction of severely resorbed mandibles with dental implants in conjunction with IAN repositioning is an effective and reliable technique. Although neurosensory disturbances are the most common complication after surgery, they tend to resolve over time. Advanced surgical skills are required to perform this technique.

Relationship between dry mouth and hypertension

OBJECTIVES

Salivary dysfunction, such as reduced salivary flow and an altered salivary composition, is caused by several diseases, medical conditions, and medications. The purpose of the present study was to clarify the relationship between hypertension and morphological changes in the submandibular glands.

MATERIALS AND METHODS

An epidemiological study was conducted to elucidate the relationship between hypertension and dry mouth. The effects of hypertension on morphological changes and the intima thickness of arteries in the submandibular glands were histopathologically investigated.

RESULTS

Among 1933 subjects in the epidemiological study, 155 (8.0%) had dry mouth. A multivariate analysis revealed that dry mouth correlated with age (p < 0.001), sex (p < 0.001), and hypertension (p < 0.05). No significant differences were observed in the size of the submandibular glands between patients with or without hypertension. The average area of acinar cells was smaller in patients with than in those without hypertension (0.366 ± 0.153 vs. 0.465 ± 0.178, p < 0.05). The arteriosclerotic index was significantly higher in patients with than in those without hypertension (0.304 ± 0.034 vs 0.475 ± 0.053, p < 0.05).

CONCLUSIONS

Hypertension may contribute to the degeneration of the submandibular glands by decreasing the number of acinar cells and promoting fatty infiltration and stenosis of the arteries.

CLINICAL RELEVANCE

There may be a correlation between hypertension and the degeneration of the submandibular glands by decreasing the number of acinar cells and promoting fatty infiltration and stenosis of the arteries.

From restoration to regeneration: periodontal aging and opportunities for therapeutic intervention

With the march of time our bodies start to wear out: eyesight fades, skin loses its elasticity, teeth and bones become more brittle and injuries heal more slowly. These universal features of aging can be traced back to our stem cells. Aging has a profound effect on stem cells: DNA mutations naturally accumulate over time and our bodies have evolved highly specialized mechanisms to remove these damaged cells. Whilst obviously beneficial, this repair mechanism also reduces the pool of available stem cells and this, in turn, has a dramatic effect on tissue homeostasis and on our rate of healing. Simply put: fewer stem cells means a decline in tissue function and slower healing. Despite this seemingly intractable situation, research over the past decade now demonstrates that some of the effects of aging are reversible. Nobel prize-winning research demonstrates that old cells can become young again, and lessons learned from these experiments-in-a-dish are now being translated into human therapies. Scientists and clinicians around the world are identifying and characterizing methods to activate stem cells to reinvigorate the body's natural regenerative process. If this research in dental regenerative medicine pans out, the end result will be tissue homeostasis and healing back to the levels we appreciated when we were young.

The Clinical Significance of Separate Measurements of Carotid Arterial Wall to Assess the Risk Factor for Atherosclerosis

Background

Carotid intima-media thickness (CIMT) is associated with several risk factors for atherosclerosis and has been consistently linked to cardiovascular and cerebrovascular disease. The clinical significance of separate measurements of CIMT, which is the sum of the intima (IT) and media thickness (MT), to use as an assessment of risk for atherosclerosis has not yet been fully established.

Methods

Among 3377 patients who underwent B-mode ultrasound of carotid arteries and coronary angiography in the Medical Department of St. Mary's Hospital from September 2003 to March 2009, 1146 subjects (M:F = 616:530; mean age, 57.7 ± 12.1 years) who were diagnosed with normal coronary arteries were enrolled in this study. IT, MT, and CIMT of the enrolled patients were manually measured using high-frequency ultrasonography (15 MHz linear array transducer).

Results

In multivariate logistic regression analysis, age (β = 0.063, p < 0.0001), body mass index (BMI) (β = 0.028, p = 0.018), and hypertension (HTN) (β = 0.046, p = 0.0002) were associated with MT (R² = 0.256) and the IT/MT ratio (R² = 0.209). Age (β = 0.065, p < 0.0001), BMI (β = 0.025, p = 0.038), hemoglobin A1c (β = 0.045, p = 0.045), and HTN (β = 0.043, p = 0.0006) correlated with mean CIMT (R² = 0.230). Age (β = -0.071, p < 0.0001) and BMI (β = -0.046, p = 0.002) were associated with the IT/MT ratio (R² = 0.219) on the left side. Age (β = 0.093, p < 0.0001) was related to MT (R² = 0.265) and mean CIMT (R² = 0.243) on the left side.

Conclusion

We noted different atherosclerotic risk factors were related to measurements of the arterial wall in different ways. Therefore, separate measurements of CIMT might be a useful method to assess the risk for atherosclerosis.

Is carotid artery evaluation necessary for primary prevention in asymptomatic high-risk patients without atherosclerotic cardiovascular disease?

Objective

Routine measurement of the carotid intima–media thickness is not recommended in recent clinical practice guidelines for risk assessment of the first atherosclerotic cardiovascular disease (ASCVD) event (the definition of which includes acute coronary syndromes, a history of myocardial infarction, stable or unstable angina, coronary or other arterial revascularization, stroke, transient ischemic attack, or peripheral arterial disease presumed to be of atherosclerotic origin). The aim of the present study was to elucidate the role of carotid artery evaluation for primary prevention of ASCVD in asymptomatic high-risk patients visiting a teaching hospital.

Methods

Eight hundred seventy-three patients (487 male [55.8%], mean age 59.4±11.5 years) who were statin-naive and without ASCVD, which was proven by coronary angiography or coronary CT angiography, were enrolled in this study. The patients underwent carotid scanning in the Medical Department of St Mary’s Hospital from September 2003 to March 2009. ASCVD outcomes were evaluated for median follow-up of 1,402 days.

Results

A total of 119 participants experienced ASCVD events. In multivariate Cox regression analysis, age (hazard ratio [HR] =1.026, 95% confidence interval [CI] =1.002–1.050, P=0.033), history of smoking (HR =1.751, 95% CI =1.089–2.815, P=0.021), statin therapy (HR =0.388, 95% CI =0.205–0.734, P=0.004), and carotid plaques (HR =1.556, 95% CI =1.009–2.400, P=0.045) were associated with ASCVD events. In middle-aged group (45≤ age <65, n=473), history of smoking (HR =1.995, 95% CI =1.142–3.485, P=0.015), statin therapy (HR =0.320, 95% CI =0.131–0.780, P=0.012), and carotid plaques (HR =1.993, 95% CI =1.116–3.560, P=0.020) were associated with ASCVD events.

Conclusion

The presence of carotid plaques, history of smoking, and statin therapy might be important factors for primary prevention of ASCVD in asymptomatic high-risk patients, especially in middle-aged patients. Therefore, the results suggest that carotid artery parameters may have an additional predictive value for primary prevention of ASCVD in the middle-aged high-risk patients.

Epidemiological aspects of rheumatoid arthritis patients affected by oral bisphosphonate-related osteonecrosis of the jaws

This literature review aims to evaluate the epidemiologic profile of patients with rheumatoid arthritis (RA) that developed a bisphosphonate-related osteonecrosis that affect the jaws (BRONJ), including demographic aspects, as well as clinical and therapeutic issues. A search of PUBMED/MEDLINE, Scopus, and Cochrane databases from January 2003 to September 2011 was conducted with the objective of identifying publications that contained case reports regarding oral BRONJ in RA patients. Patients with RA who develop oral BRONJ are usually women above 60 years taking steroids and long-term alendronate. Most of them have osteoporosis, and lesions, triggered by dental procedures, are usually detected at stage II in the mandible. Although there is no accepted treatment protocol, these patients seem to have better outcomes with conservative approaches that include antibiotic therapy, chlorhexidine, and drug discontinuation.

Increasing hepatic arteriole wall thickness and decreased luminal diameter occur with increasing age in normal livers

BACKGROUND & AIMS

There is no data to suggest that the size of bile ducts, portal venules, and hepatic arterioles varies according to age in the normal human liver. We sought to examine whether hepatic arteriolar size, wall thickness, and luminal diameter change with increasing age.

METHODS

Histologically normal liver specimens from 90 live and deceased donors were separated into three groups of thirty: donor age<30, 31-60, and>60years old. Trichrome-stained slides were de-identified and assessed by a liver pathologist blinded to donor age. Morphometric measurements were taken of the hepatic arteriole, the cross-sectional diameter, and its wall thickness. The arteriole was measured at its widest diameter, the arteriolar wall at its thickest portion, and the luminal diameter between its widest points.

RESULTS

There was no difference in number of arterioles or bile ducts or in arteriolar cross-sectional diameter among the groups and no correlation with age was found. An increasing arteriolar wall thickness and a decrease in luminal diameter with advancing age were noted; no difference in bile duct size among the groups was found. There was a significant difference in wall thickness/total cross-sectional diameter with extremes in age (21-30 age group vs. 71-80 age group, p=0.0009) with an accompanying significant decrease in luminal diameter/cross-sectional diameter between the same groups (p=0.00002).

CONCLUSIONS

Increasing hepatic arteriolar wall thickness and decreased arteriolar cross-sectional diameter occur with increasing age in the normal human liver.

Unique origin of the inferior alveolar artery

The inferior alveolar artery is the major blood supply to the mandible and mandibular teeth. This artery has a very consistent path, originating from the maxillary artery and passing inferiorly until it enters the mandibular foramen, accompanied by the inferior alveolar nerve and vein. During routine dissection of a 90-year-old female cadaver, a unique origin of the inferior alveolar artery was observed on the left side. The artery branched off the external carotid artery, just superior to the stylohyoid and posterior belly of the digastric muscle in the posterior region of the submandibular triangle. From its starting point the artery passed superiorly in the stylomandibular fascia and made a curving arch into the pterygomandibular space to enter the mandibular foramen with the inferior alveolar nerve. The position and branching pattern of the maxillary artery were otherwise typical. The inferior alveolar artery on the right side displayed a normal branching pattern within the infratemporal fossa. Results of surgical procedures in this area, such as sliding osteotomy of the mandible, could be impacted by this anomaly.

Pharmacological properties of serotonin receptor subtypes mediating contraction of bovine inferior alveolar arteries

OBJECTIVE

To characterise the 5-hydroxytryptamine (5-HT) receptor subtypes mediating contraction of the inferior alveolar artery. Additionally, to determine the role of cyclooxygenase products, nitric oxide, endothelium, monoamine oxidase and 5-HT uptake in modulating contraction of inferior alveolar arteries to 5-HT.

METHODS

Contractile responses to 5-HT were examined in vitro using ring segments of bovine inferior alveolar arteries. Affinity constants (K(B)'s) of subtype-selective 5-HT receptor antagonists were determined to characterise the 5-HT receptor-subtypes causing contraction of inferior alveolar arteries.

RESULTS

In 100 nM ketanserin or 30 nM spiperone, 5-HT caused a biphasic contraction best-fit by a two-site curve model, where one site was antagonist-sensitive and the other site antagonist-insensitive. 5-HT(2A) receptor-subtype selective antagonists, ketanserin and spiperone, blocked 5-HT induced contraction with K(B)'s of 1.0 and 0.16 nM, respectively. RS102221 (5-HT(2C) selective) and (S)-WAY100135 (5-HT(1A) selective) blocked 5-HT stimulated contraction with low affinities (K(B)'s=100 nM and 330 nM, respectively). GR55562, a 5-HT(1) receptor subtype antagonist with a reported affinity of 500 nM at the 5-HT(1D) receptor subtype, blocked 5-HT induced contraction with a K(B) of 470 nM. Cylooxygenase inhibition with 50 microM ibuprofen caused a 44% increase in maximal contraction to 5-HT; whereas, nitric oxide inhibition with N(G)-nitro-L-arginine, endothelium removal or inhibition of 5-HT uptake and monoamine oxidase with imipramine and iproniazid, respectively, did not affect 5-HT contraction.

CONCLUSIONS

Both 5-HT(2A) and 5-HT(1D/1B) receptor subtypes mediate 5-HT induced contraction of the bovine inferior alveolar artery. 5-HT stimulated contraction of the inferior alveolar artery is modulated by a vasodilator prostaglandin.