Retrospective Evaluation of Implants Placed in Iliac Crest Autografts and Pristine Bone.

OBJECTIVE: Iliac crest autografts can compensate for severe mandibular atrophy before implant placement. However, the implant success in the augmented bone is not entirely predictable. Here we performed a retrospective cohort study to determine the success and related parameters of implants placed in augmented bone and pristine bone for up to 11 years. MATERIAL AND METHODS: We analyzed 18 patients where 72 implants were placed six months after iliac crest transplantation and 19 patients where 76 implants were placed in pristine bone. The primary endpoint was implant loss. Secondary endpoints were the implant success, peri-implant bone loss, and the clinical parameters related to peri-implantitis. Moreover, we evaluated the oral-health-related quality of life (OHIP). RESULTS: Within a mean follow-up of 5.8 ± 2.2 and 7.6 ± 2.8 years, six but no implants were lost when placed in augmented and pristine bone, respectively. Among those implants remaining in situ, 58% and 68% were rated as implant success (p = 0.09). A total of 11% and 16% of the implants placed in the augmented and the pristine bone were identified as peri-implantitis (p = 0.08). Bone loss was similar in both groups, with a mean of 2.95 ± 1.72 mm and 2.44 ± 0.76 mm. The mean OHIP scores were 16.36 ± 13.76 and 8.78 ± 7.21 in the augmentation and the control group, respectively (p = 0.35). CONCLUSIONS: Implants placed in iliac crest autografts have a higher risk for implant loss and lower implant success rates compared to those placed in the pristine bone.

Topical Cyclosporine in Oral Lichen Planus-A Series of 21 Open-Label, Biphasic, Single-Patient Observations.

Topical cyclosporine (CSA) has been reported as an alternative treatment in steroid-refractory oral lichen planus (OLP), but evidence is limited and conflicting. An N-of-1 trial setting could be appropriate to evaluate interindividual differences in treatment response. We studied a series of 21 open-label, biphasic single-patient observations. Patients (15 women, 6 men) with OLP recalcitrant to topical steroids received four weeks of CSA mouth rinse (200 mg/twice daily) followed by four weeks of drug withdrawal. Pain (visual analogue scale (VAS) score), disease extent (physicians' global assessment (PGA) score) and quality of life (Dermatology Life Quality Index (DLQI) score,) were assessed at baseline (T0), after four weeks of treatment (T1) and after another four weeks without treatment (T2). Median age was 58 years (interquartile range/IQR = 52-67) and median disease duration was 18 months (IQR = 12-44). Median baseline VAS score decreased significantly at T1 (p = 0.0003) and increased at T2 (p = 0.032) (T0 = 5 (IQR = 3-6.5); T1 = 2 (IQR = 0.5-3.4); T2 = 3 (IQR = 2-4.8)). Similarly, median baseline PGA score decreased significantly at T1 (p = 0.001) and increased at T2 (p = 0.007) (T0 = 2 (IQR = 1.3-2.5); T1 = 1 (IQR = 1-2); T2 = 2 (IQR = 1-2)). Median baseline DLQI score also decreased significantly at T1 (p =.027) but did not change at T2 (p = 0.5) (T0 = 2.5 (IQR = 1-5.8); T1 = 1 (IQR = 0-3); T2 = 1 (IQR = 1-4)). CSA responders (n = 16) had significantly higher median baseline VAS scores (5.2 (IQR = 5-6.5)) than nonresponders (n =5) (2 (IQR = 2-3.5) (p = 0.02). In our study, pain, disease extent and quality of life of patients with OLP improved significantly during therapy with low-dose CSA mouth rinse and exacerbated after drug withdrawal. Remarkably, patients with high initial VAS scores seemed to profit most.

A Longitudinal Seroprevalence Study Evaluating Infection Control and Prevention Strategies at a Large Tertiary Care Center with Low COVID-19 Incidence.

Personal protective equipment and adherence to disinfection protocols are essential to prevent nosocomial severe acute respiratory syndrome coronavirus (SARS-CoV-2) transmission. Here, we evaluated infection control measures in a prospective longitudinal single-center study at the Vienna General Hospital, the biggest tertiary care center in Austria, with a structurally planned low SARS-CoV-2 exposure. SARS-CoV-2-specific antibodies were assessed by Abbott ARCHITECT chemiluminescent assay (CLIA) in 599 health care workers (HCWs) at the start of the SARS-CoV-2 epidemic in early April and two months later. Neutralization assay confirmed CLIA-positive samples. A structured questionnaire was completed at both visits assessing demographic parameters, family situation, travel history, occupational coronavirus disease 2019 (COVID-19) exposure, and personal protective equipment handling. At the first visit, 6 of 599 participants (1%) tested positive for SARS-CoV-2-specific antibodies. The seroprevalence increased to 1.5% (8/553) at the second visit and did not differ depending on the working environment. Unprotected SARS-CoV-2 exposure (p = 0.003), positively tested family members (p = 0.04), and travel history (p = 0.09) were more frequently reported by positively tested HCWs. Odds for COVID-19 related symptoms were highest for congestion or runny nose (p = 0.002) and altered taste or smell (p < 0.001). In conclusion, prevention strategies proved feasible in reducing the risk of transmission of SARS-CoV-2 from patients and among HCWs in a low incidence hospital, not exceeding the one described in the general population.

In vitro adherence of Candida albicans to zirconia surfaces.

OBJECTIVES: This study aimed to characterize surface properties such as roughness (Ra) and surface-free energy (SFE) of glazed and polished yttria-stabilized zirconia and to evaluate in vitro adherence of fungus Candida albicans and salivary bacteria, Staphylococcus epidermidis, mixed with C. albicans to these substrata. Additionally, the influence of salivary proteins (albumin, mucin and α-amylase) on yeast adhesion was studied. MATERIAL AND METHODS: Ra and SFE of glazed and polished zirconia discs were measured. Specimens were wetted with saliva and salivary proteins prior to incubation with C. albicans and mixed suspension of C. albicans and S. epidermidis for 24 hr, respectively. Microbial adhesion was quantified by counting colony-forming units (CFU). Differences in physicochemical properties were proved by t test. "Linear mixed model" with the factors "type of surface" and "wetting media" was applied to analyse the effects on fungal adhesion (p < .05). RESULTS: SFE and Ra of glazed specimens were significantly higher than corresponding values of polished ones. The wetting media significantly changed the fungal binding (p = .0016). Significantly higher quantities of adhering fungi were found after mucin incubation compared to saliva (p = .004). For the factor "surface" as well as the interaction between "surface" and "wetting media," no statistically significant differences have been found. In mixed suspension, the growth of Candida was completely prevented. CONCLUSIONS: Glazed and polished zirconia differs in terms of physicochemical surface properties. These differences appear to be modulated by pellicle coating affecting the biomass of adhered Candida. Mucin seems to be good binding sites for adhesion of C. albicans.

Does osteoporosis influence the marginal peri-implant bone level in female patients? A cross-sectional study in a matched collective.

BACKGROUND/PURPOSE: Osteoporosis, being a homeostatic imbalance, affects the remodeling of bone. Whether this catabolic bone disease influences peri-implant marginal bone remodeling remains unknown so far. The purpose of this study was to evaluate the influence of osteoporosis on peri-implant marginal bone loss (MBL) in postmenopausal women. MATERIALS AND METHODS: In a matched collective, radiographic peri-implant bone level (at baseline and at follow-up examinations) was compared in healthy and osteoporotic women. General health and behavioral history of the patients were recorded using a printed questionnaire. RESULTS: A best fit matching procedure generated a sample of 48 women with a total of 204 implants matched at patient and implant level that was further statistically analyzed. The mean mesial MBL-statistically corrected to report the first year-was -0.6 ± 1.2 mm (range: -5.1 to 2.2) in the healthy control group and -1.1 ± 1.3 mm (range: -5.3 to 2.2) in the osteoporotic group. Similarly, the mean distal MBL was -0.5 ± 1.3 mm (range: -5.1 to 4.8) in the healthy control group and -1.2 ± 1.3 mm (range: -4.7 to 1.6) in the osteoporotic group, respectively. The base linear regression models including solely osteoporosis and time without any other confounders revealed a significant influence of osteoporosis and time since implant placement on the MBL at the mesial and the distal implant aspect. The significance of osteoporosis on bone loss did not change incorporating the confounders: bone level at implantation, smoking, jaw, location, surface, concrement, plaque, augmentation, edentulism in opposing and implant jaw, bisphosphonates, vitamin D, fixed versus removable prosthetics, connection type. CONCLUSIONS: There is no contraindication to place dental implants in osteoporotic patients. This study implicates to respect the bone level at implant placement and not to place the implant below bone level if possible.

Morphometric analysis of sinus depth in the posterior maxilla and proposal of a novel classification.

The aim of this study was to analyse the posterior maxillary sinus based on its extension into the alveolar process and to provide a simple clinical classification. A retrospective cohort study was conducted in CT scans of 200 dentate and 200 edentulous patients (100 women and 100 men, respectively). After manual placement of 12 reference points morphometric analysis was performed and sinus depth, residual alveolar ridge height (RH) and the sinus opening angle were calculated. Sinuses were classified according to the quartiles of sinus depth: class I (above the hard palate), class II (0-6 mm below the hard palate) and class III (>6 mm below the hard palate). Sinus depth was found to be a reliable anatomical landmark and did not vary significantly between gender (p = 0.8940) or dentition groups (p = 0.9723). Alveolar height varied significantly between sinus classes (p < 2 × 10-16) and dentition groups (p < 2 × 10-16) but not between genders (p = 0.5178). The sinus opening angle was significantly different between sinus classes (p < 2.2 × 10-16) but not between gender or dentition groups. We propose a novel classification built upon the quartiles of sinus depth, dividing the sinuses into three classes. Our classification is the first one that represents the anatomy of the patient independent of gender and dentition.

Effectiveness of subperiosteal bone anchor (Onplant) placement in the anterior highly atrophic maxilla for cross-arch prosthetic rehabilitation: Results from a pilot study.

PURPOSE: The present prospective pilot study aimed to evaluate the feasibility of Onplants (Onplant Orthodontic System) off label use in the highly atrophic edentulous maxillae of adult patients to avoid bone grafting and conventional dental or zygomatic implants. MATERIAL AND METHODS: Two Onplants were placed subperiosteally in the anterior part of the hard palate in five adult patients presenting a highly atrophic edentulous maxilla, class V or VI, according to Cawood and Howell. After a healing period of 4 months the prosthetic procedures were started. Outcome measures were the survival rate of the Onplant system, complication rate and OHRQoL using a OHIP-G questionnaire at three different stages: before and after the Onplant placement and at the end of treatment. RESULTS: Unexpectedly, the present study had to be discontinued due to the early loss of all 10 Onplants at the time of prosthetic loading. In total, 16 patients were meant to participate, but the study was stopped after complete failures of the first five patients. While all inserted Onplants became unstable, no other complications like penetration of the nasal cavity, infections or fractures of the abutment screw were observed. The patient satisfaction and the oral health-related quality of life declined with the number of surgical interventions and finally with the Onplant failure. CONCLUSIONS: The anterior part of the adult hard palate apparently did not present adequate bone regenerative capacity to support Onplant-prosthetic rehabilitation. Off-label Onplant-supported prostheses are contraindicated for permanent maxillary rehabilitation in edentulous adult patients. Conflict-of-interest statement: The original manufacturer provided the materials free of charge in this investigator-sponsored research (code: 2011-1027). The authors declare no conflicts of interest in relation to this study.

Alveolar bone regeneration in response to local application of calcitriol in vitamin D deficient rats.

AIM: Vitamin D deficiency is considered to diminish bone regeneration. Yet, raising the serum levels takes months. A topic application of the active vitamin D metabolite, calcitriol, may be an effective approach. Thus, it becomes important to know the effect of vitamin D deficiency and local application on alveolar bone regeneration. MATERIAL AND METHODS: Sixty rats were divided into three groups; two vitamin depletion groups and a control group. Identical single defects (2 mm diameter) were created in the maxilla and mandible treated with calcitriol soaked collagen in one deficiency group while in the other two groups not. Histomorphometric analysis and micro CTs were performed after 1 and 3 weeks. Serum levels of 25(OH)D3 and PTH were determined. RESULTS: Bone formation rate significantly increased within the observation period in all groups. Bone regeneration was higher in the maxilla than in the mandible. However, bone regeneration was lower in the control group compared to vitamin depletion groups, with no significant effects by local administration of calcitriol (micro CT mandible p = 0.003, maxilla p < 0.001; histomorphometry maxilla p = 0.035, mandible p = 0.18). CONCLUSION: Vitamin D deficiency not necessarily impairs bone regeneration in the rat jaw and a single local calcitriol application does not enhance healing.

Effect of personality traits on the oral health-related quality of life in patients with oral mucosal disease.

OBJECTIVES: The aim of this study was to assess the relationship between oral health-related quality of life, the nature of mucosal disease, and personality traits. METHODS: One hundred forty-nine patients seeking care for oral mucosal disease were recruited in this cross-sectional study conducted at the University Clinic of Dentistry in Vienna from June to December 2013. All participants agreed in answering two questionnaires: the Oral Health Impact Profile German version (OHIP-G), which assessed the perceived limitations of oral health-related quality of life and the Neuroticism Extraversion Openness Five-Factor Inventory (NEO-FFI), which evaluated five personality domains. A multiple linear regression was applied to examine the potential influence on OHIP scores. RESULTS: Bullous/erosive mucosal diseases and oral lichen planus patients (n = 73, 49% of total) reported the highest impact on oral health-related quality of life (OHIP total score 49.3 ± 35.7, p = 0.02). A highly significant influence of neuroticism, as a personality trait, was observed on oral health-related quality of life (p = 0.001). Women had significantly more restrictions (OHIP score 45.3 ± 32.2) compared to men (32.6 ± 30.1, p = 0.009). CONCLUSIONS: Psychosocial factors such as personality traits, especially neuroticism, are significantly associated with quality of life ratings in patients with mucosal disease. CLINICAL RELEVANCE: Since mucosal diseases impact patient's daily living and quality of life while affected by their psychological profiles, this should be considered when formulating a therapeutic approach.

Dental implants are a viable alternative for compensating oligodontia in adolescents.

OBJECTIVES: To clinically and radiographically evaluate dental implant treatment in adolescents with extensive oligodontia. METHODS: Patients with more than nine permanent teeth congenitally missing and implant treatment before the age of 16 years were included. Clinical follow-ups involved bleeding on probing, plaque index and peri-implant probing value. The peri-implant bone level was analysed on panoramic radiographs at time of implant treatment and at follow-up. Characteristics of the dental implants and patients were retrieved. RESULTS: This study involved 18 patients (nine males, nine females) having 71 dental implants. The lower left premolar was predominantly missing. The mean age at the time of dental implant treatment was 12.5 (± 2.6) years. The bleeding on probing value was determined negative on 44%. The mean pocket depth was 3.6 (± 1.1) mm. The peri-implant bone level correlated significantly negative with the age at time of implant placement (r = -0.346, P = 0.004). The region of implant habits had no influence on peri-implant bone level. Dental implant treatment in adolescents resulted in a survival rate of 89% (63/71) and a mean loading time of 11.0 (± 4.1) years. The implant crowns to be renewed resulted in 54% (9 of 18 patients, 38 of 71 crowns) after a period of 7.8 ± 4.5 years. CONCLUSION: Dental implant treatment in maturing adolescents with extensive oligodontia before is supported by the data of the present study. Providing that other treatment options are considered, the areas of skeletal growth are respected and the patients are well informed. To enhance quality of life of growing children with oligodontia clinicians are asked to evaluate their long-term outcome on dental implant treatment in adolescents.

Decontamination of autogenous bone grafts: systematic literature review and evidence-based proposal of a protocol.

There is a lack of consensus guidelines for the decontamination of autogenous bone grafts after exposure to a nonsterile environment during graft contouring, intraoral bone harvesting, or when inadvertently dropped off the sterile field. Transplantation of contaminated bone may cause infectious complications or even augmentation failure. When selecting the antimicrobial agent of choice to treat harvested bone for transplantation purposes, focus should be placed on the safety of the agent towards bone and osteoprogenitor cells, maximum elimination of targeted pathogens that directly affect bone tissue, and a short exposure time. In systematically reviewing study results on the degree of bone graft contamination and the effects of decontamination methods, a protocol for decontamination of autogenous bone grafts is proposed. Among various decontamination agents investigated, 1% chlorhexidine proved highly effective (mean reduction of bacterial colony-forming units compared to saline solution: 99.97%). Minimum contact time required is 15 seconds and cell proliferation can be observed up to 30 seconds of exposure. The proposed decontamination protocol (1% chlorhexidine for 15 seconds) seems to represent a reasonable compromise in reference to sterility and cell viability. Comparative effectiveness research, however, is needed before clinical recommendations may be posed.

Impact of implant surface topography: a clinical study with a mean functional loading time of 85 months.

OBJECTIVE: Moderately rough, surfaced implants are widely used. Nevertheless data on long-term soft and hard tissue parameters are still conflicting. The purpose of this study was to evaluate peri-implant bone level and soft tissue integration of anodized vs. turned surfaced implants in the anterior mandible after a mean functional loading time of 85 months. METHODS: Of 114 edentulous patients invited for follow-up, 41,2% were available for recall. Forty-seven patients with a mean age of 71 ± 9 years (14 men and 33 women) received 188 dental implants; All patients were edentulous and prosthetic rehabilitation was carried out by a bar-retained overdenture. Radiographic peri-implant bone level was assessed twice at baseline and recall. Clinical examination contained peri-implant sounding (PPD, BoP) and indexing oral hygiene (mPI). RESULTS: From baseline up to 85 months two patients experienced implant loss (four implants), which corresponds to an overall-survival rate of 97.9%. No significant differences were found between implant surfaces concerning the clinical parameters, such as plaque, calculus, bleeding on probing and pocket probing depth. The moderately rough surfaced implants showed significantly less decrease in peri-implant bone level (1.53 ± 0.25 mm) than turned surfaced implants (2.42 ± 0.34 mm) (P = 0.036). The interaction between the position of the implant and surface topography (P = 0.037) as well as the site at the implant (P = 0.004) had a significant influence on bone level changes. CONCLUSION: Both surface topographies with bar-supported overdentures have excellent long-term clinical outcomes. Moreover, a moderately roughened, anodized surface has beneficial effects in the anterior lower jaw.

The use of onplants and implants in children with severe oligodontia: a retrospective evaluation.

OBJECTIVE: To evaluate a stable treatment concept for the oral rehabilitation of children with severe oligodontia. The treatment is intended to solve a specific problem caused by limited skeletal growth, multiple congenital missing teeth, underdeveloped bone volume and young age. MATERIAL AND METHODS: A surgical/prosthodontic approach was chosen for six patients with subtotal edentulism despite their young age. To support removable dentures the maxilla was treated with onplants (OnPlant), whereas dental rootform implants (NobelReplace, Nobel Biocare) were placed in the mandible. RESULTS: Eight onplants were placed in the hard palate of four patients for rehabilitating the maxilla and eight dental rootform implants were placed interforaminally in three patients to rehabilitate the mandible. While none of the rootform implants was lost, one onplant was lost and replaced with a stable outcome. The mean follow-up time of the onplants was 5 (±1) years vs. 3 (±2) years for the rootform implants. CONCLUSION: The evaluation showed the treatment concept described to ensure stable oral rehabilitation and recovery of the stomatognathic system even during the juvenile growth period.

Effect of maxillary sinus floor augmentation on sinus membrane thickness in computed tomography.

BACKGROUND: Little is known about maxillary sinus compliance, i.e., the intrinsic potential of the sinus membrane to resume its homeostatic status after the surgical trauma caused by sinus floor elevation. The aim of the present study is to investigate the effect of maxillary sinus floor augmentation on sinus membrane thickness. METHODS: Within-patient comparison of computed tomographic scans before bone grafting versus 4 to 6 months after bone grafting was performed. Changes in membrane thickness were evaluated in 65 maxillary sinus floor augmentation procedures via a lateral approach in 35 patients without clinical signs of sinus pathology at any time. RESULTS: Sinus membrane thickness differed significantly before (0.8 ± 1.2 mm) versus after (1.5 ± 1.3 mm) augmentation surgery (P <0.001), with a mean increase of 0.8 ± 1.6 mm (maximum: 4.4 mm). Only 28% of augmented sinuses did not show membrane thickening. In non-augmented control sinuses, there was no evidence of membrane thickness increase. CONCLUSIONS: The results indicate that the maxillary sinus membrane, even in healthy clinical conditions, undergoes morphologic modifications after sinus floor elevation, yet membrane reactions demonstrate significant variability. Future research on the effect of augmentation surgery on maxillary sinus physiology is recommended.

Impact of dietary vitamin D on osseointegration in the ovariectomized rat.

AIM: Vitamin D deficiency is highly prevalent in the population and associated with impaired peri-implant bone regeneration. Yet, there is a gap in understanding the impact of vitamin D supplementation on the process of osseointegration. In this study, the effect of vitamin D supplementation on peri-implant bone regeneration was investigated. METHODS: Fifty ovariectomized Sprague-Dawley rats were divided into three groups. The depletion group was fed a vitamin D-free diet for 8 weeks. The repletion group received vitamin D-free diet for 6 weeks, before animals were switched to standard diet containing 2400 IU/kg vitamin D. The control group was fed the standard diet. Two titanium mini-implants were placed in the tibia. All groups remained on their previous diet until sacrifice. Blood sample testing and histomorphometric analysis were performed. RESULTS: Vitamin D depletion caused a significant reduction in 25-hydroxvitamin D in rat serum that returned to control levels in the repletion group. This vitamin deficiency was associated with a decrease in bone-to-implant contact in the cortical area, which was leveled to controls in the repletion group. No significant changes by vitamin D depletion were noticed in the medullar compartment. Moreover, also the peri-implant bone area and the mineral apposition rate remained unchanged upon vitamin D depletion. CONCLUSION: These results indicate that vitamin D deficiency has a negative impact on cortical peri-implant bone formation in ovariectomized rats, which can be compensated by vitamin D supplementation. This study provides first insight into the potential beneficial effect of vitamin D supplementation in implant dentistry.

Peri-implantitis and late implant failures in postmenopausal women: a cross-sectional study.

AIM: Systemic bone loss is a major cause of fractures in postmenopausal women and may also affect the jawbone; however, its consequences on the success of dental implants remain poorly understood. MATERIALS AND METHODS: In this cross-sectional study, the relation between self-reported osteoporosis and the success rate of dental implants in an adult female population was evaluated. The primary outcome parameters were the occurrence of peri-implantitis and late implant failures. Women with unknown bone status were excluded from the study. The potential confounders age, recipient site, smoking, periodontal disease and time of loading were recorded. RESULTS: Data from 203 women with a mean age of 63 ± 9 years and 967 dental implants were investigated. The patients were classified according to their medical history into one of three groups: osteoporosis (47 women), osteopenia (16 women) and healthy controls (140 women). Patients with unknown bone status (n=26) were excluded. The multi-level statistical analysis showed no association between peri-implantitis [odds ratio (OR) 2.1; p=0.6] or implant failure [hazards ratio (HR) 2.5; p=0.2] and systemic bone loss. CONCLUSIONS: No relation was found between osteoporosis and peri-implantitis in an adult female population.

Cortical porosity of the mandible in an osteoporotic sheep model.

OBJECTIVES: Cortical porosity and thickness of the axial and the appendicular skeleton are predictors of osteoporotic fractures. In the jawbone, however, cortical porosity and thickness may affect the mechanical stability of dental implants. We have shown previously that the jawbone of osteoporotic sheep has impaired trabecular structures, but whether catabolic bone turnover also accounts for the cortical bone porosity remains unknown. MATERIAL AND METHODS: We compared mandibular bone from six geriatric sheep subjected to ovariectomy, calcium/vitamin D restriction, and methylprednisolone administration to those of six healthy adult control sheep. Histological ground sections were prepared from the diastema, first and second premolars, and postmolar region. Cortical porosity and thickness were assessed by histomorphometry. RESULTS: Cortical porosity was higher in osteoporotic sheep than in adult controls in the diastema and in the first and second premolar region. In the postmolar region, the difference failed to reach the level of significance. The changes were even more prominent when histomorphometry was restricted to the inner millimeter of the mandibular cortex. In contrast, induction of osteoporosis did not have a discernable effect on cortical thickness. CONCLUSION: These results demonstrate that cortical porosity of mandibles is more pronounced in geriatric osteoporotic sheep than in adult controls.