Aesthetic assessment of implant-supported replacement, related factors and solutions to improve outcome
One of the key issues in dentistry management is the failure of post crowns. These are some of the teeth which were saved from extraction through the process of root filling and enhancing the support through the provision of retention and crowning on top of the post. This is an advanced treatment with an effect of restorative form and an attempt to bar the tooth from failing. Depending on various factors prognosis can take a few months to many years after a successful function.
Core retention has been used extensively when there is minimal remaining tooth substance; this has been undertaken by post retention of the core. The post aids in retaining the restoration effect. The post needs to also protect the remaining structure of the tooth remaining. These functions can be assessed through the retentive nature of the posts and the resistance of the fracture.
In this s state, an occurrence of the dental sinus is occurring with an abnormal nature which may drain the dental abscess associated with the dead tooth. The dental sinus may drain to the inside of the mouth or the skin surface. The occurrence of dental sinus arises from chronic infection and necrotic dental pulp. The decay occurs due to trauma or caries. Caries arises from poor dental hygiene and increased intake of refined sugars.
On post shape occurrence, parallel side post offers good retention and minimal stress formation process and increases the resistance of the fracture (Cheung, 2005). Increasing the post length may have a positive outcome, however, restrictions tend to apply to post length. The endodontic restoration apical seal is ensured to ensure 5-6 mm maintenance. Further, the apical teeth dentin is often weak which increases the risks of perforation and weakens the tooth increasing the occurrence of root fracture. Based on this increasing the post diameter has not been used as a reliable measure to improve the overall retention.
A finite element formation study has shown that formation of stress in the dentine lowers the diameter and increases fracture resistance. The root canal needs not be enlarged. With the surface design, serrated posts tend to provide better retention ability. Superior retention is obtained through engaging dentin increases the stress on the root structure thus increasing the fracture of the root.
In assessing the tooth structure remains on the crown, the cave surface of the prepare intact. In this case, a considerable amount of dentin is present. Caries removal and cleaning of the area will thin out the tooth structure remains while still trying to fix it will make to be loose. Due to the limited retention, the need for bonding of the post and crown with resin cement is paramount. This will keep the retention in place and can increase also the risks of tooth fracture especially now their dental sinus occurrence.
Another effect of the post retained success entails the ferrule effect. This allows the teeth to prepare a ferrule of 1.5-2 mm demonstrating superior fracture resistance levels. Root fracture often varies from patient to patient, however, after root fracture, the tooth needs an implant. It is fundamental to note whether the post loosens the fracture, as they can lead to failure. Either way, the tooth will need a replacement with an implant. The key aspect with the restoration of endodontic ally treated teeth is the amount of the structure of the teeth. Strong tooth structure supports effective restoration.
The overall aesthetic value would evolve around bone tissue enhancement. Greater loss of bone and tissue leads to a poor ideal aesthetic result. Missing tooth leads to greater potential for bone restoration to occur, inadequate bone support lowers the ability of stable implant. Another key aspect is optimal implant location. Receding gum tissue in wound healing often can be a factor in achieving a positive outlook. A recommendation to this can be moving the teeth displaced so as to improve spacing towards improving positive aesthetic value. Other parameters can be the choice of implants, soft tissue management and prosthetic design of the implants.
Selecting the right and optimal implant is key in managing the choice of implant for the patient. Managing the soft tissue can entail surgical management of wound healing to improve the gingival and reconstructing the gum with additional tissue grafts. This leads to a positive restorative process. In adjusting prosthetic designs, the crown can be modified to reduce the overall interdental space volume. This is essential when the black triangle is left between the teeth due to inadequate papilla.
Occlusion relevance in implant dentistry and alteration by parafunction on the implant management
The application of occlusal factors in dental implants prognosis has been essential for clinical success purposes and the longevity of rehabilitated treatment options (Sadowsky, 2019). Implant overloads are linked to mechanical complication overload on failure to treatments after the restoration of the patient function. The most prevalent failure forms are the loosening of the screw, clinical crown fracture, prosthesis fracture and bone loss at crest level on loosing of the implant (Lavigne et al., 2008).
Studies have shown that occlusal factors are critical in rehabilitations and fixing prosthetic treatment management options. Thus in this case the underlying principles can be used in reducing the overload of the implant and bone tissue interface while managing the occlusal overload over the implant unit in the physiological limit. The key factor to consider in physiological difference is the natural teeth and the osseointegrated implants. . This difference is often observed during initiation of treatment and could lead to an overload or failure of the rehabilitation process of the dental. Poor observance of this difference at the beginning of treatment can lead to an overload which could lead to dental rehabilitation failure process (Heitz-Mayfield et al., 2004).
The key difference of natural and dental teeth leads to the occurrence of the periodontal ligament. Dental implants have minimal resilience as compared to natural teeth due to this absence of periodontal ligament. The periodontal ligament has receptors that confer tactile sensitivity aspects protecting the teeth and overall occlusal overloading in the periodontal cavity. The apical cavity is found in the apical third level of the teeth. The charges are absorbed and stress distribution in the bone tissue area. The key signs clinically for periodontal ligament overload entail the thickening process, dental wear facets and mobility aspects. Dental implants are not protected by excessive occlusal forces due to a lack of natural buffer. The proprioceptive aspects are governed by the osseoperception (Nishigawa, Bando & Nakano, 2001). Thus in this case the crestal bone in the implant plays a role of a fulcrum when there is an applied force including a greater susceptibility of the bone loss in the peri-implant sections (Schindler, Turp, Blaser & Lenz, 2005). Occurrence of occlusal overload can lead to failure of one or more components of the implants, which can lead to fracture occurrence, loosening of connecting screws, excess wear of implant or structural aspects of the dental area.
In general, the underlying concepts of establishing implant-supported occlusion are key in reducing the occlusal overload in the prosthesis and protecting the overall implants of osseointegration (Sadowsky, 2019). The key principle of the implant protection of occlusion entails the bilateral stability in the centric occlusion, lack of occlusal interference and equal occlusion contact distribution process. Adoption of the procedures has been shown to modify or change cumulative effect factors which lead to overloads of the implants (Laney, 2007).
Despite differences in studies, stress distribution patterns with regards to the type of loading and direction can be linked to the parafunctional simulation process activity linked with non-axial loads which could lead to occlusal overload in dental implants. This could extend to the adjacent bones. In a study assessing parafunctional loading, there were an induced increase of 33% von mises stress and about 60% maximum principal stress levels.
The loading effect of parafunctional impact at 1.5 C/I (crown height with 15 mm) demonstrated a poor biomechanical state, leading to an increase in the stress levels in the components and bone tissue levels. According to Misch et al (2008) crown height higher than 15 mm is biomechanically unfavourable as the generated stress could lead to peri-implant stress leading to loosening of the screw neck as compared to displacement effect in the crown, especially in parafunctional activity.
Stress can be more intense when undertaking parafunctional loading, where the direction and magnitude can influence the applied load levels on the implant level and transfer of the stress to the nearby bone. In clinical practice, the occlusal adjustment process, could lead to a reduction table and lower the cusps slope allowing better occlusion forces distribution and lowering the stress levels.
Based on studies done (Torcato et al., 2014), implant proportion elavation improves the concentration of implant stress components and the cortical bone. The parafunctional loading tends to increase by four to five times the magnitude of stress in the bone tissue levels as compared to the functional loading processes.
What criteria would you consider when deciding to extract or save a lower first molar tooth?
Extraction therapy is a viable treatment option that might be considered in teeth management. Once this process has been accepted, the next stage is to assess which teeth are the most suitable candidate under the clinical presentation available. A key point to note is that every tooth is a potential candidate for extraction under key circumstances. Under the normal state, there are acceptable guidelines for the consideration of extraction therapy. The initiation guideline is to extract the teeth which are near to the deform site, desired change or crowding. Another fundamental guideline is consideration of the dental unit to be removed, and assessment on the effects on the contacts, occlusion and functionality basis. Fundamental interests are whether the therapy can deepen the bite or lead to functional group as compared to canine guidance occurrence during the lateral excursion, which could create food impact areas interdentally or other relational factors. Another consideration also entails the pattern of the extrication process as to whether it might lead to asymmetrical midline occurrence.
Tooth choice for extraction needs to be assessed as to whether it impacts the overall pattern of the skeletal. In short consideration as to whether there is the closing effect of the vertical dimension process, the relationship effect of the anteroposterior effect occurrence. A classical example is o whether the first four premolars of the Cl II Div II have a similar relative maxillo-mandibular discrepancy or the upper 4’s and lower 5’s or the only the upper 4’s offer better A-P correction.
The choice of teeth extraction needs to consider the overall patient periodontal support which needs to be balanced on the scheduled remaining teeth. With this aspect, tangential consideration is key in atypical extraction which is considered based on the results of the anchoring considerations and secondary occlusal disharmony occurring. Another fundamental aspect is how the implants can be used to enhance or create an anchorage state in the dental formula.
Another factor to consider in tooth extraction is the esthetical state relative to the extracted teeth vis-a vis the smile and midline aspects. This occurs in aspects where there is exhibiting severe displacement of upper lateral incisor or canine impacted with limited prognosis for the appropriate retrieval process. There is need also to assess whether there is the presence of asymmetry, if positive, then is the asymmetry dental; skeletal or functional. Further, would the extraction therapy be indicative of asymmetry present and further would this incorporation with inter arch or intra arch mechanics lead to an asymmetry were none existent.
In undertaking these considerations, each tooth can be a potential for the tooth extraction process through guidelines. Viswanath, et al. (2010) observed that selection of tooth for orthopaedic extraction is a fundamental aspect that needs to be modified based on the individual patient. The premolar extraction process has been implemented for many years. Every tooth has to be extracted based on the orthodontic therapy process for varied reasons such as the longevity period, importance and space available, periodontal aspects surgical issues or restorative aspects.
Cotez et al (2010) demonstrated that key aspect in molar extraction is the treatment of skeletal bites by providing functional results with greater stability as compared to the non-extraction treatment process. Despite high mandibular plane ankles with or lacking the anterior open bite, the molar is extracted in cases where there is increased posterior crowding, caries, hypoplastic nature lesions, greater restoration effects, high plane angle of mandibular and presence of an open bite.
The maxillary first molars are extracted when there is greater posterior crowning and minimal need for the changes to the soft tissue anterior part, thus conventional protraction of the third or second molar needs to be considered. The root structure of the anterior part needs to offer a sufficient storage process to meet the dental unit demands. The third molars need to be in a viable state for eruption and functional. These cases require adequate time for the consideration process with regards to space available. Extraction of the first molars in this case has a greater impact on lowering the vertical dimension as compared to extraction of the interiorly positioned dental level. Extraction of the first mandibular molars has critical considerations with regard to the potentiality of the third molar eruption success.
Monolithic zirconia crown process on first molar tooth.
With the emergence of dental care, Zirconia has been used extensively as the material of choice with regards to advanced technological advancement and providing patients with metal-free restoration. Zirconia has aided in availability of milling pucks which offers greater variation shade and translucencies which resemble the natural dentine process. Further, it has improved esthetics, the zirconia properties offer strength, durability and precise fitting restoration process. In improving the success of monolithic zirconia restoration lowering chair time, it is crucial to flow proper guiltiness in this process.
Importance of tooth design preparation
- It offers a smooth edge which leads to lower stress levels and decreases the impact of fracture occurring.
- Ceramic restoration needs passive fit
- The Uniform reduction process is key in ideal ceramic strength levels
- Adequate reduction offers the best esthetic results output and
- Applicable digital scanners offer smooth preparations and increased accuracy.
Guidelines stages for a posterior Zirconia crown
When undertaking to prepare posterior Zirconia tooth crown, there is a need to ensure adequate wall level thickness and have 0.55 mm minimum and between 1-1.5 mm occlusal reductions. The tapping is made between 4°and 8°. It needs to have clear circumferential chamfer and lowering 0.5mm is needed for gingival margin levels. Despite the shoulder and chamfer preparations being profound, feather edges are not advised but can be accepted for full zirconia crowns.
Factors to consider which may hamper crown setting for Zirconia restoration process
An acceptable zirconia restoration, the preparation do not need to have undercuts and should not have gutter aspects. The 90 degrees shoulder and parallel wall sets are not accepted. Further, sharp incisal edges are not effective for zirconia restoration.
In esthetic zone restoration, zirconia crown facial or full layer offers optimal results .layering porcelain approach offers a significant improvement to the zirconia substructure. For a full-contour monotheistic zirconia crown, there is a need for 1.0 to 1.5 mm depth of occlusion so as to achieve an effective occlusal anatomy level. There is a need to ensure that there is 1.0 to 1.5 mm functional level tip reduction, gingival chamfer reduction level of 0.55 mm, 6-8 degrees tapping to the axial walls and 1.00 mm occlusal with a 1/3 functional cusp reduction level.
In cementing and finishing the restoration of zirconia, marginal finishing is key in fitting and cementing the restorations. Removal of excess cement is key in removing and avoiding the formation of the plaque which can increase periodontal disease and sensitivity issues. Gingival margins are removed using safe ending finishing and non-cutting burs which protects the soft tissues. Despite this adjustments can roughen the tissues, polishing and smooth surface creation should be easy.
If adjustments are necessary then the application of fine diamond bur essential for Zirconian restoration can be applied. Excess heat can lead to microfractures on the Zirconia. Further, it is essential to use small pressure so as to lower the heat produces. Using water is essential in cooling the restoration process.
Risks based dentistry and its application in implant dentistry
Oral health risk management aids in comprehensive and personalized therapy for better care and optimal outcomes. A common approach employed entail risks stratified assessment and treatment. It improves health outcomes and quality of life and prevents acceleration of high risks categories (American Academy of Family Physicians, online). In dentistry, risks assessment is key in evaluating periodontal diseases and carriers which are foundational goals. Risks assessment is a crucial aspect in dentistry and is employed by about 98% of dental hygienists (Francisco et al 2013).
Oral health risks offer an understanding of the oral disease probability of occurrence and changes which might arise due to clinical, behavioural or protective approaches adopted (Riley et al., 2013). Assessment and identification of patient-oriented risk assessment offer a baseline for determining the risks status of the patients especially based on low, moderate or high levels (Zero et al., 2001).
Carries risks assessment was proposed by Featherstone et al (Young & Featherstone, 2013) to be used in two phases; the first phase allows for individual indicator of underlying risks and if any protective factors offer any mitigation process. The second aspect offers determination on the level of risks. The presence of disease is linked to higher risks and a higher number of risks factors shows higher risks. According to Bader et al (2003) disease indicators are linked to moderate to high risks of caries which can entail gross teeth cavitation, multiple restorations, plaque accumulation and root surface exposures.
Periodontal risks assessment entails weighing the disease indicators together with risks and protective factors (Lang et al., 2012). The disease measures are linked to lose attachment, formation occurrence and probe bleeding (Lang, Suvan and Tonetti, 2012). Most conditions associated with high risks states entail diabetes and smoking (Lindskog et al., 2010). carries risks assessment can further investigate non-biological factors such as environmental factors, oral health aspects and health behaviours.
Implant dentistry requires an assessment of a treatment plan which is suitable for the patient. This is essential with regard to treatment plans in the estethic zone. The primary goal is to provide a higher level of outcome and limited risks level (Dawson, Chen, et al. 2009). With this in mind various factors have to be considered;
Implant dentistry is not easy, it needs adequate knowledge on achieving perfect esthetic, phonetic and functional level outcomes. Further, they aid in recovery in alveolar bone reconstruction and of tissues of peri-implant. As a process to aid this the Swiss Society of Oral Implantology (SSOI) and the International Team for Implantology (ITI) have developed the SAC - S = Straightforward, A = Advanced, and C = Complex system for surgical and prosthetic processes in dentistry (Dawson, Chen, et al. 2009). Immediate placements are complex and treatment is limited to surgeons with expertise. The increased expertise level is essential in complementing physical assessment viewpoints.
Patient individual profile assessment is essential when formulating a treatment plan for both implant process and conventional approaches. Various factors can alter this approach from a straightforward implant to a non-implant care process for the patient. An assessment of systematic risk on the well being of the patient is essential.
Recognizing the disease state and conditions of patients requiring an implant is vital. It is essential to recognize the impacts which affect the healing process, bone remodelling process and long term care for the patient. Systematic indications for implants patients are divided into two sections high risks patients and significant risks groups. The former represents those with serious systematic conditions such as bone diseases, HIV, arthritis and substance abuse while the latter comprises those with radiotherapy, bleeding states, severe diabetes and smoking.
Implementation of risks assessment is essential in understanding patient behaviour and modelling an effective treatment plan. Risks assessment offers an understanding and motivates the patients towards an effective better health outcome. True risks treatment process offers a medical and dental team to offer timely management to high risks patients and prevent future diseases.
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