Peri-implant radiographic bone level and associated factors in Spain.

OBJECTIVES: To evaluate radiographic bone level (RxBL) at dental implants and its associated factors in Spain. MATERIAL AND METHODS: This cross-sectional study was performed by a network of sentinel dentists from regions of Spain. RxBL was defined as the distance from the implant shoulder to the first clearly visible contact between the implant surface and the bone. Radiographic measurements were performed by two trained and experienced periodontists. Implant and patient data were also collected. Descriptive, bivariate, discriminative and multivariate analyses were done. RESULTS: A total of 49 sentinel dentists provided data 275 patients. Mean RxBL from 474 implants (5-13 years) was 1.87 mm (range: 0.00-13.17 mm). Statistically significant associations between RxBL and clinical output variables (bleeding on probing, oedema, plaque, probing depth, suppuration, keratinized tissue) were found. In the multiple regression analysis, statistically significant associations for RxBL were found for smoking habit, implant diameter, years of follow-up and type of prosthesis (p < 0.01). CONCLUSIONS: Peri-implant RxBL ranged from 0 to 13.17 mm. It was significantly associated with clinical output variables and with some potentially predictor variables, at patient- (smoking >10 cigarettes/day) and implant- (diameter, years of follow-up, Toronto bridge) levels.

Differences in the progression of experimental peri-implantitis depending on the implant to abutment connection.

OBJECTIVES: The aim was to evaluate the rate of bone loss progression during experimentally induced peri-implantitis using two different implant-abutment connections in implants with identical surface topography. MATERIAL AND METHODS: Forty-eight Regular Neck tissue-level SLA implants with a matching implant to abutment connection (TL) and 36 bone-level SLA implants with a switching platform implant to abutment connection (BL) were subjected to experimental peri-implantitis in two independent in vivo pre-clinical investigations. Experimental peri-implantitis was induced by means of silk ligatures during 3 months (induction phase), and followed for one extra month without ligatures (progression phase). Radiographic and clinical outcomes were evaluated longitudinally along both studies and subsequently compared between experiments. RESULTS: During the induction phase, radiographic bone loss was significantly higher in implants with matched abutments compared with those with platform switching connections (2.65 ± 0.66 mm vs 0.84 ± 0.16 mm, respectively, p = 0.001). During the progression phase, both types of implant-abutment connection exhibited similar rates of radiographic bone loss. Similar outcomes were observed clinically. CONCLUSIONS: A platform switching connection resulted in a more benign development of peri-implantitis during the experimental induction phase of the disease. These differences, however, disappeared once the ligatures were removed (progression phase). CLINICAL RELEVANCE: Influence of the implant-abutment connection in peri-implantitis progression may be relevant when considering implant selection in the moment of placement. In this sense, platform switching abutment demonstrated less peri-implantitis development when compared to implant matching connection.

Implant placement in fresh extraction sockets.

Recent systematic reviews have shown that the survival rate of immediate implant placement is similar to those with a delayed approach. However, preclinical models and human studies have shown that immediate implant placement per se does not preserve the anatomy of the alveolus, mainly at the buccal bone crest, leading to bony dehiscences and subsequently to soft-tissue recession, with a great impact on esthetic outcomes. On the other hand, preclinical and human studies have identified factors that may prevent bone resorption after immediate implant placement, such as anatomical/biological (alveolus, gingival biotype, periapical/periodontal pathology) and surgical/restorative ones (implant diameter and positioning, flap/flapless, bone and connective tissue grafts, immediate loading/provisionalization, antibiotics). Taking these factors together and with a critical treatment plan made by an expert professional, the immediate treatment approach could be possible and beneficial for the patient.

Mechanical and chemical implant decontamination in surgical peri-implantitis treatment: preclinical "in vivo" study.

OBJECTIVE: The aim of the present study was to evaluate the effect of a titanium brush and chemical agents following surgical treatment of experimental peri-implantitis. MATERIAL AND METHODS: Six implants were installed in the mandible of eight beagle dogs (unit of analysis) 3 months after tooth extraction. Experimental peri-implantitis was induced 3 months later. The defects were randomly allocated in three treatment groups: (a) TiBrush(™)  + sodium hypochlorite + chlorhexidine (TBH), (b) TiBrush(™)  + chlorhexidine (TB), (c) an ultrasonic device + chlorhexidine (US). The distal implant in each hemimandible was used as control, and no treatment was done. Clinical and histological measurements were performed after 3 months of healing. RESULTS: All treatment procedures resulted in statistically significant improvements of all clinical parameters. Histomorphometrical analysis revealed no statistically significant differences between treatment groups in terms of woven bone height (primary outcome). However, there were differences between test and control groups in terms of inflammation, bone defect depth and bone refill without differences between TBH and TB groups. CONCLUSIONS: Resolution of peri-implantitis after access surgery and decontamination of peri-implant surfaces with TiBrush(™) with or without sodium hypochlorite is possible. However, the concomitant use of sodium hypochlorite has minor effect on treatment outcomes.

Soft tissue dimensions in flapless immediate implants with and without immediate loading: an experimental study in the beagle dog.

OBJECTIVE: The aim of the present study was to evaluate the peri-implant soft tissue dimensions in flapless immediate implants with and without immediate loading. MATERIAL AND METHODS: This study was carried out on six beagle dogs. Four implants were placed (two per side) immediately after tooth extraction (third and fourth premolars). Flapless immediate implant placement was performed in one hemimandible (control). The same procedure was performed in the contralateral side and immediate prosthesis was connected (test). After 3 months of healing, the dogs were sacrificed. RESULTS: None of the implants and prosthesis were lost. Barrier epithelium in the loaded group was 2.51 mm at the buccal and 2.34 mm at the lingual aspect. In the no loaded group, the results were similar, 2.54 and 2.2 mm at the buccal and lingual side, respectively. Connective tissue in the loaded group was 1.38 mm at the buccal and 0.65 mm at the lingual aspect, and in the no loaded group 1.48 mm at the buccal and 0.53 mm at the lingual side. Biological width dimensions were 3.9 mm at the buccal and 2.95 mm at the lingual aspect for the loaded group, and 4.01 and 2.64 mm at the buccal and lingual aspect for the no loaded group. CONCLUSIONS: The results of the present study suggested that soft tissues dimensions around immediate implants with immediate loading were similar to immediate implants without loading.

Unfolding the Human Milk Microbiome Landscape in the Omics Era.

Studies conducted in the last years have demonstrated that human milk represents a continuous supply of beneficial bacteria to the infant gut, which contribute to the maturation of the digestive and immune functions in the developing infant. Nevertheless, the origin of bacterial populations in milk is not fully understood yet and they have been proposed to originate from maternal skin, infant's mouth, and (or) endogenously, from the maternal digestive tract through a mechanism involving immune cells. Understanding the composition, functions and assembly of the human milk microbiota has important implications not only for the infant gut microbiota establishment, but also for the mammary health since dysbiosis in the milk bacteria may lead to mastitis. Besides, host, microbial, medical and environmental factors may affect the composition of the human milk microbiome, with implications for the mother-infant health. Application of both culture-dependent and -independent techniques to assess the milk microbiome faces some practical limitations but, together, have allowed providing novel and complementary views on its origin, composition and functioning as summarized in this minireview. In the next future, the application of the ultimate advances in next-generation sequencing and omics approaches, including culturomics, will allow a detailed and comprehensive understanding of the composition and functions of these microbial communities, including their interactions with other milk components, expanding the opportunities to design novel microbiome-based modulation strategies for this ecosystem.

Microbiota of human precolostrum and its potential role as a source of bacteria to the infant mouth.

Human milk represents a source of bacteria for the initial establishment of the oral (and gut) microbiomes in the breastfed infant, however, the origin of bacteria in human milk remains largely unknown. While some evidence points towards a possible endogenous enteromammary route, other authors have suggested that bacteria in human milk are contaminants from the skin or the breastfed infant mouth. In this work 16S rRNA sequencing and bacterial culturing and isolation was performed to analyze the microbiota on maternal precolostrum samples, collected from pregnant women before delivery, and on oral samples collected from the corresponding infants. The structure of both ecosystems demonstrated a high proportion of taxa consistently shared among ecosystems, Streptococcus spp. and Staphylococcus spp. being the most abundant. Whole genome sequencing on those isolates that, belonging to the same species, were isolated from both the maternal and infant samples in the same mother-infant pair, evidenced that in 8 out of 10 pairs both isolates were >99.9% identical at nucleotide level. The presence of typical oral bacteria in precolostrum before contact with the newborn indicates that they are not a contamination from the infant, and suggests that at least some oral bacteria reach the infant's mouth through breastfeeding.