The placement of dental implants in the anterior maxilla is a challenge for clinicians because of patients' exacting esthetic demands and difficult pre-existing anatomy. This article presents anatomic and surgical considerations for these demanding indications for implant therapy. First, potential causes of esthetic implant failures are reviewed, discussing anatomic factors such as horizontal or vertical bone deficiencies and iatrogenic factors such as improper implant selection or the malpositioning of dental implants for an esthetic implant restoration. Furthermore, aspects of preoperative analysis are described in various clinical situations, followed by recommendations for the surgical procedures in single-tooth gaps and in extended edentulous spaces with multiple missing teeth. An ideal implant position in all 3 dimensions is required. These mesiodistal, apicocoronal, and orofacial dimensions are well described, defining "comfort" and "danger" zones for proper implant position in the anterior maxilla. During surgery, the emphasis is on proper implant selection to avoid oversized implants, careful and low-trauma soft tissue handling, and implant placement in a proper position using either a periodontal probe or a prefabricated surgical guide. If missing, the facial bone wall is augmented using a proper surgical technique, such as guided bone regeneration with barrier membranes and appropriate bone grafts and/or bone substitutes. Finally, precise wound closure using a submerged or a semi-submerged healing modality is recommended. Following a healing period of between 6 and 12 weeks, a reopening procedure is recommended with a punch technique to initiate the restorative phase of therapy.

Optimizing esthetics for implant restorations in the anterior maxilla: anatomic and surgical considerations.

PURPOSE To compare the expression of the pro- and anti-inflammatory forms of interleukin (IL)-1 in the tear fluid and conjunctival epithelium of normal eyes and those with dry-eye disease METHODS The concentrations of IL-1 alpha, IL-1 beta (precursor and mature forms), and IL-1 receptor antagonist (IL-1Ra) were measured by ELISA in tear fluid samples obtained from normal individuals and patients with dry eye who had rosacea-associated meibomian gland disease (MGD) or Sjogren's syndrome (SS) aqueous tear deficiency (ATD) These cytokines were also measured in normal tear fluid before and after nasal stimulation to induce reflex tearing The relative expression of these cytokines was evaluated in conjunctival impression cytology specimens and conjunctival biopsy tissue obtained from normal subjects and SS ATD-affected patients using immunofluorescent staining Matrix metalloproteinase (MMP)-9 concentration and activity in the tear fluid were evaluated with gelatin zymography and with an MMP-9 activity assay kit, respectively RESULTS Compared with normal subjects, the concentration of IL-1 alpha and mature IL-1 beta in the tear fluid was increased, and the concentration of precursor IL-1 beta was decreased in patients with MGD (P < 005, P = 002, and P < 001, respectively) and SS ATD (P < 0001, P = 002, and P < 0001, respectively) There was no significant change in the concentration of IL-1 alpha, precursor IL-1 beta, and IL-1Ra in reflex tear fluid, indicating that the lacrimal glands may secrete these cytokines The activity of MMP-9, a physiological activator of IL-1 beta, was significantly elevated in the tear fluid of both dry-eye groups compared with normal subjects A strong positive correlation was observed between the intensity of corneal fluorescein staining and the tear fluid IL-1 alpha concentration (r(2) = 017, P < 002) and the mature-to-precursor IL-1 beta ratio (r(2) = 046, P < 0001) Positive immunofluorescent staining for IL-1 alpha, mature IL-1 beta, and IL-1Ra was observed in a significantly greater percentage of conjunctival cytology specimens from eyes with SS ATD than in those from normal eyes (P < 001 for IL-1 alpha, P < 0009 for mature IL-1 beta, and P < 005 for IL-1Ra) CONCLUSIONS Dry-eye disease is accompanied by an increase in the proinflammatory forms of IL-1 (IL-1 alpha and mature IL-1 beta) and a decrease in the biologically inactive precursor IL-1 beta in tear fluid Increased protease activity on the ocular surface may be one mechanism by which precursor IL-1 beta is cleaved to the mature, biologically active form The conjunctival epithelium appears to be one source of the increased concentration of IL-1 in the tear fluid of patients with dry-eye disease These results suggest that IL-1 may play a key role in the pathogenesis of keratoconjunctivitis sicca

Pro- and anti-inflammatory forms of interleukin-1 in the tear fluid and conjunctiva of patients with dry-eye disease.

Global risk factors and risk indicators for periodontal diseases

Position paper: epidemiology of periodontal diseases.

Aims: To review the literature related to the analytical epidemiology of periodontitis generated over the past decade. This review does not deal with descriptive epidemiologic studies of the prevalence, extent and severity of periodontitis with respect to global geography, but focuses exclusively on analytical epidemiology issues, including the challenges posed by the use of different case definitions across studies, current theories and models of disease progression, and risk factors associated with the onset and progression of periodontitis.

Methods: Relevant publications in the English language were identified after Medline and PubMed database searches.

Findings and conclusions: There is a conspicuous lack of uniformity in the definition of periodontitis used in epidemiologic studies, and findings from different research groups are not readily interpretable. There is a lack of studies that specifically address the distinction between factors responsible for the onset of periodontitis versus those affecting its progression. Colonization by specific bacteria at high levels, smoking, and poorly controlled diabetes have been established as risk factors for periodontitis, while a number of putative factors, including specific gene polymorphisms, have been identified in association studies. There is a clear need for longitudinal prospective studies that address hypotheses emerging from the cross-sectional data and include established risk factors as covariates along with new exposures of interest. Intervention studies, fulfilling the “targeting” step of the risk assessment process, are particularly warranted. Obvious candidates in this context are studies of the efficacy of elimination of specific bacterial species and of smoking cessation interventions as an alternative to the traditional broad anti-plaque approach in the prevention and control of periodontitis. Ideally, such studies should have a randomized-controlled trial design.

Analytical epidemiology of periodontitis

Background: Periodontitis is a bacterial disease modified by multiple risk factors. The pro-inflammatory cytokine interleukin-1 (IL-1) is a key regulator of the host responses to microbial infection and a major modulator of extracellular matrix catabolism and bone resorption. It has been reported that variations in the IL-1 gene cluster on chromosome 2 are associated with increased susceptibility to severe adult periodontitis. Methods: The present study evaluated the association between a composite IL-1 genotype, including allele 2 at each of two loci (IL-1A +4845 plus IL-1B +3954), and a broad spectrum of periodontally healthy to diseased patients in a population that is typically encountered in a dental practice setting. Ninety patients, non-smokers or former smokers with less than 10 pack-year (pk/yr) history, were recruited from a private dental practice. The major outcome variable was bone loss determined by computerized linear measurements of radiographs. Genotypes were analyzed from finger-stick bl...

Interleukin-1 genetic association with periodontitis in clinical practice

Background: The study of occlusal therapy in humans with periodontitis is problematic due to potential irreversible bone loss in control subjects. The hypothesis of this pilot investigation was that increased interocclusal contact initiated by shortterm occlusal splint disuse would increase tooth mobility and the bone-resorptive cytokine interleukin (IL)-1β in gingival crevicular fluid (GCF), comparable to IL-1–positive genotype and increased periodontitis severity. Methods: Nineteen non-smoking chronic periodontitis patients using nocturnal occlusal splints and undergoing periodontal maintenance in a private practice were evaluated at five time points: 24 hours after continuous splint use; 1, 2, and 3 days after no occlusal splint use; and 14 days after resumption of customary nighttime splint use. Subjects were evaluated to confirm that the plaque index and gingival index were ≤1.0, and to categorize past periodontitis (moderate or severe) and IL-1 genotype (1A +4845 plus IL-1B +3954). Test sites on two...

Michael J. McDevitt

Papers

Interleukin-1 genetic association with periodontitis in clinical practice

Impact of Increased Occlusal Contact, Interleukin-1 Genotype, and Periodontitis Severity on Gingival Crevicular Fluid IL-1β Levels