Vitamin D deficiency and periodontal clinical attachment loss in HIV-seropositive women: A secondary analysis conducted in the Women's Interagency HIV Study (WIHS).

OBJECTIVE: The aim of this study was to test a hypothesized positive association between low vitamin D (VitD) serum levels and the severity of periodontal disease in women with HIV infection. STUDY DESIGN: This was a cross-sectional secondary analysis of data from an oral substudy conducted within the Chicago site of the Women's Interagency HIV Study. Serum VitD levels and clinical attachment loss (CAL) measurements were available for 74 women with HIV infection. VitD levels were treated as both continuous and categorical variables in bivariate and multivariate analyses. Mean clinical attachment loss (mCAL) was determined for each subject by obtaining the averages of measurements taken at 4 sites in each measured tooth. RESULTS: Average age of study participants (n = 74) was 39.6 years (standard deviation 7.2), and the majority were African Americans (70.3%) with VitD deficiency (58.1%). VitD deficiency was positively associated with higher mCAL (P = .012). After adjustment for race, age, smoking, and HIV viral load, an association was found between VitD deficiency and mCAL (Beta 0.438; P = .036). CONCLUSIONS: We identified a previously unreported association between VitD deficiency and mCAL in women with HIV infection. Larger and more inclusive, multisite, longitudinal studies are warranted to investigate whether these findings can be generalized to all individuals with HIV infection in the current treatment era and to determine causality.

Complications Associated With the Use of Recombinant Human Bone Morphogenic Protein-2 in Ridge Augmentation: A Case Report.

This case report aims to describe in detail a complication associated with resorption of regenerated bone following implant placement and ridge augmentation using recombinant human bone morphogenic protein-2 (rhBMP-2) in combination with allograft and xenograft. Bilateral maxillary sinus and ridge augmentation procedures were completed using rhBMP-2 combined with allograft and xenograft. Five months later, significant bone augmentation was achieved, which allowed for the placement of 4 implants. Upon stage 2 surgery, significant dehiscence was noted in all implants. Treatment steps to address this complication included implant removal, guided bone regeneration with xenograft only, and placement of new implants followed by soft-tissue grafting. At the time of publication, this patient is status 1½ years post case completion with maintenance of therapy outcomes. Off-label use of rhBMP-2 has gained significant acceptance in implant dentistry. However, there is limited evidence regarding the bone maturation process when rhBMP-2 is combined with other biomaterials. More research may be needed regarding the timing and process of bone healing in the presence of rhBMP-2, in an effort to avoid surgical complications.

MMP-8 overexpression and persistence of neutrophils relate to stress-impaired healing and poor collagen architecture in mice.

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) are critical for tissue remodeling during wound repair. Psychological stress has been found to impair wound healing in humans and animals. The objective of this study was to assess MMP and TIMP gene expression during stress-impaired healing. Female SKH-1 mice (n=299) were divided into control and stress groups (13h restraint/day for 3days prior to and 5days post-wounding). Two 3.5mm cutaneous full-thickness wounds were placed on the dorsum of each mouse and wound measurements were performed daily. RT-PCR for gene expression of MMP-2, MMP-8, MMP-9, TIMP-1 and TIMP-2 was performed at days 1, 3 and 5. Immunohistochemical analyses of the healed wounds were performed at days 15 and 28. As expected, wounds healed more slowly in restraint-stressed mice compared to controls. Stressed mice exhibited MMP-8 overexpression and lower TIMP-1 levels during healing, and poorer collagen organization once healed. MMP-8 overexpression may have stemmed from a higher level of neutrophils, observed in wound tissue on days 3 and 5. These findings implicate higher neutrophil numbers, MMP-8 overexpression, and TIMP-1 under-expression, as mechanisms that may compromise wound outcomes such as scarring under conditions of stress.

Restraint stress impairs early wound healing in mice via alpha-adrenergic but not beta-adrenergic receptors.

Stress negatively influences wound healing in a clinically relevant manner. In an animal model, repeated restraint stress (RST) impairs wound healing in mice, partially through stress-induced glucocorticoid (GC) release. However, the role of stress-induced catecholamines (i.e., (nor)epinephrine) in healing has not been elucidated. In the present study, two 3.5mm round dermal wounds were placed on the backs of mice. Animals were restrained overnight for 3 days prior to and 5 days post-wounding. Prior to RST, mice were injected with either phentolamine or nadolol: non-specific alpha- and beta-adrenergic receptor antagonists, respectively. Pictures were taken daily to measure the rates of wound closure and contraction. Blockade of alpha-adrenergic, but not beta-adrenergic receptors, attenuated impairments in wound closure and contraction, and normalized edema, in RST mice. Thus, although stress impairment in wound healing clearly involves GCs, catecholamines play an important role via alpha-adrenergic receptor stimulation.

Impaired wound contraction and delayed myofibroblast differentiation in restraint-stressed mice.

Previous research has shown that psychological stress delays wound closure by >25%. Gene expression of pro-inflammatory cytokines and the maturation of the epithelium were also impaired by stress (Mercado et al.). Wound contraction contributes to the speed of wound closure (Hunt and Hopf). In the current study, wound contraction was decreased by >45% (p<.01) in restraint stressed mice. Fibroblast migration and differentiation into smooth muscle alpha-actin (SmalphaA) -expressing myofibroblasts were delayed in RST mice through day 7 post-wounding. In addition, there was a 25 (p<.01), 48 (p<.01), and 38% (p<.05) decrease in SmalphaA mRNA levels at days 1, 3, and 5 post-wounding in RST mice, respectively. Cytokines that regulate fibroblast migration and differentiation include transforming growth factors-beta1, -beta2, and -beta3 (TGF-betas). Although expression of TGF-beta1 mRNA was downregulated by >25% (p<.01) in RST mice on day 3 post-wounding, no significant differences were detected in active or total TGF-beta1 protein levels. Stress did not alter the expression of TGF-beta2 or -beta3 through day 5 post-wounding. Thus, these data indicate that stress delays wound contraction and myofibroblast differentiation, which are likely independent of expression of TGF-beta1, -beta2, and -beta3.

Hyperbaric oxygen therapy ameliorates stress-impaired dermal wound healing.

Psychological stress has been shown to dysregulate healing in both humans and animals. Studies indicate the possibility for decreased oxygen supply, and increased oxygen demand, in the wounds of the stressed animals. Oxygen is an important mediator of wound healing, and its availability can limit healing rate. Hence, in a mouse model of stress-impaired healing, the hypothesis that hyperbaric oxygen therapy would ameliorate the effect of stress on dermal wound healing was tested. Hyperbaric oxygen therapy (HBO) twice a day during early wound healing significantly ameliorated the effects of stress, bringing healing to near-control levels. There was no significant effect of HBO on the wounds of control animals. Wound inducible nitric oxide synthase (iNOS), modulated by psychological stress and oxygen balance, was studied for gene expression by real-time PCR. Expression of iNOS increased in stressed mice on days 1 (205%; p<.0001), 3 (96%; p<.03), and 5 (249%; p<.03), post-wounding. HBO treatment of the stressed animals decreased iNOS expression by 62.6% (p< .02) day 1 post-wounding. There was no significant effect of HBO on wound healing and iNOS expression in the control animals. Methods aimed at increasing tissue oxygenation, like HBO, have a high therapeutic potential. Their molecular mechanisms, implicated in wound healing, elude clarification due to the lack of appropriate animal models. Our current findings represent the first experimental evidence, demonstrating that HBO corrects stress-impaired dermal wound healing.