Space Maintenance in Pediatric Dentistry PDF

Maintenance in Pediatric Dentistry Dr. Rabab M. Abd El Hakam Researcher at the National Research Centre, Orthodontics and Pediatric Dentistry Department Lecturer at Ahram Canadian University Member of th...

Maintenance in Pediatric Dentistry Dr. Rabab M. Abd El Hakam Researcher at the National Research Centre, Orthodontics and Pediatric Dentistry Department Lecturer at Ahram Canadian University Member of the Egyptian Society for Pediatric Dentistry and Children with Special Needs (ESPSN) Member of Center for Oral Dental and Health Promotion (CODE HP) ILOS After this lecture students will be able to : Identify the different types of space maintainers Identify indication and contraindication of space maintainer construction Identify factors affecting space maintainer construction Solve problem cases Identify types of arch analysis Contents Consequences of premature loss of Primary teeth Factors Affecting space maintainers’ construction Requirements of space maintainer Indications & Contraindications of space maintainer Types of space maintainers Arch Analysis Consequences of premature loss of Primary teeth Crowding / tooth impaction Midline shift Retrusion of the anterior segment Increased overbite Arch length inadequacy (2-4mm/quadrant) Factors affecting space maintainer construction Time elapsed since loss of primary tooth Dental developmental age of the child Amount of bone covering the permanent successor Sequence of eruption  Delayed eruption of permanent teeth Congenital absence of permanent teeth Degree of development of the permanent successor Requirements of Space maintainer 1. Simple design 2. Hygienic 3. Durable and corrosion resistant 4. Easily adjustable 5. Reasonable in cost and time 6. Prevent abnormal tooth movement 7. Must not hamper normal growth pattern Indications of Space Maintainers 1. Tooth loss and space analysis indicates arch length adequacy/sever crowding 2. Tooth loss and space analysis indicates a possible arch length inadequacy for teeth, there is malocclusion or abnormal habits 3. Within 6 months of tooth loss 4. Amount of bone covering more than 1mm 5. Disorder in the sequence of eruption 6. Delayed /altered eruption of permanent teeth 7. Congenital absence of permanent tooth Contraindications of space maintainers 1. No alveolar bone over erupting tooth 2. Significant arch discrepancy requiring orthodontic treatment 3. Excess space 4. Space closure desired for congenital absence of tooth 5. High caries activity and poor oral hygiene 6. Poor patient and parent cooperation Classification of Space Maintainers Removable Fixed Semi Fixed Means of Retention Partial Denture Band & Loop Active lingual Arch Complete Chrome steel & Active Transpalatal Denture Loop Bar Spoon Distal shoe Denture Passive Lingual Arch Modified Fixed Partial Denture Transpalatal Bar Nance Holding Classification of Space Maintainers Active (Semi-Fixed) Activity Passive (All Others) Functional (Partial,Complete& spoon Denture) Non Functional (All others) SPACE MAINTAINERS FOR PRIMARY MOLAR  1- Band and loop Space Maintainer It is the most commonly used space maintainer for maintaining the space of a single tooth It is a unilateral fixed appliance for space maintenance in the posterior area It has a simple cantilever design Ideally the loop portion should be wide bucco-lingually to allow for the eruption of the permanent premolars without removing the appliance The loop should be in close approximation to the ridge without impinging on soft tissue  Advantages: 1. Easy to make and economic 2. Takes little chair time 3. Hygienic 4. Durable and corrosion resistant Disadvantages: 1. Does not restore masticatory function 2. Will not prevent the continuous eruption of the opposing teeth  2- Crown and Loop Space Maintainer Indicated if the posterior abutment tooth has had extensive caries and require pulp therapy It requires preparation of the abutment tooth for the stainless steel crown and then the loop is soldered to the crown Disadvantages: It is hard to make adjustments to the loop in case of crown coverage so it is recommended to adapt a band and loop over a cemented crown  3- Passive Lingual Arch It is a bilateral fixed space maintainer indicated in case of multiple losses of teeth in the mandibular arch Lower permanent incisors should be erupted. In case of presence of primary incisors a bilateral band and loop is indicated The bands are adapted to first permanent molars and the wire should closely adapt to the cingulum areas of the permanent incisors and lingual surfaces of posterior teeth There are two types of lingual arch: a. Fixed: where the appliance is entirely passive to prevent undesirable movement of the teeth b. Fixed – removable (semi-fixed, active): in which the ends of the wire are fitted into tubes on the bands 4-Trans-Palatal Arch Space Maintainer Indicated in case of upper bilateral loss of primary molars Bands are adapted to the maxillary first permanent molar and a bar adapted to the palate will be soldered to the bands, thus It aims to prevent the maxillary molars from mesial movement  5-Nance holding appliance It is a fixed bilateral space maintainer used in the upper arch in case of bilateral loss of first primary molar or multiple losses of primary molars It does not touch the lingual surfaces of the upper anterior teeth The wire is contoured against the slope of the anterior portion of the palate approximately 1 cm distal to the lingual surfaces of the central incisors to help retain the cured acrylic button Disadvantages: Unhygienic and causes tissue irritation and inflammation in the area of the acrylic button  6- Distal Shoe Space Maintainer Before eruption of the first permanent molar: It’s used to guide the first permanent molar into its normal position it may be crown or band maintainer with distal shoe extension ( intra-gingival extension) The first primary molar distal to the space is used as the abutment tooth  DENTURES SPACE MAINTAINERS  1- Removable Partial Denture Recommend only in case of cooperative children It restores function esthetic and prevents abnormal speech and tongue habits Denture flanges should be relatively short, properly contoured and match the color of the natural mucosa The clasps may be made of stainless steel wire or of tooth colored materials  2- Spoon Denture It is a removable appliance usually it is used to replace a single tooth lost in the anterior region It has no clasps so it depends on the vault of the palate for its retention Contraindications: a. Uncooperative patient b. Epileptic patient c. Patient allergic to acrylic  3- Modified Fixed Partial Denture Bands are adapted on the last molars in the arch A wire arch will be adapted on the bands touching the lingual surfaces of posterior teeth passively and passing over the crest of the ridge of the edentulous area then an acrylic base is applied engulfing the wire Arch Analysis Materials needed: Sharp divider A set of periapical films Millimeter ruler Brass wire 0.026 inch A set of study models  1- Nance Arch Analysis Nance analysis aim to predict the adequacy or inadequacy of the arch length of the dental arch Nance concluded that the length of the dental arch from the mesial surface of one mandibular first permanent molar to mesial surface of the corresponding mandibular molar on the opposite side is shortened during the transition from the mixed to the permanent dentition due to the normal mesial drifting of the first permanent molars  Leeway space of Nance Is the combined mesiodistal widths of deciduous canine, first and second molars is more than that of the combined mesiodistal width of permanent canine, first and second premolar Nance observed that the average patient’s mandibular arch a Leeway space of 1.7 mm per side while the difference in the maxilla is 0.9 mm per side  Procedure: Measure the width of the erupted four permanent incisors from the study model using a sharp divider Measure the width of the un-erupted permanent canine, first and second premolars from the peri-apical radiograph Sum both measurements to get the required space which is the space needed for accommodation of all the permanent teeth anterior to the first permanent molar  Determine the available space for eruption of the permanent teeth using soft brass wire by contouring it to the individual arch shape and placed on the occlusal surfaces over the contact points of the posterior teeth and the incisal edges of the anterior teeth The wire should extend from the mesial surface of the first permanent molar on one side to the mesial surface of the corresponding molar on the other side  Compare between the required space and the available space If required space = available space i.e. arch length adequacy If required space more than available space i.e. Crowding If required space less than available space i.e. Spacing  2- Moyer’s Arch Analysis Moyer developed a Probability chart used to predict the mesio-distal widths of canines and premolars It can be completed in the mouth as well as on the casts and can be used for both arches  Procedure: Measure the mesio-distal width of the erupted four permanent incisors Determine the predicted sum of widths of the un-erupted permanent canine, first and second premolars (required space) using the tables available based on the sum of widths of the permanent incisors Measure the available space in the arch for eruption of the permanent canine and premolars using a divider from the distal surface of the lateral incisor to the mesial surface of the first permanent molar in each quadrant Estimate the adequacy of space for un-erupted permanent canine and premolars by comparing the measurements in steps 2 and 3 Moyer’s Probability Chart 3- Tanaka and Johnston Analysis It’s a variation of Moyer’s analysis except that the prediction table is not needed The estimated widths, (in millimeters) of the un- erupted permanent canine and premolars correspond to the 75% level of probability in Moyer’s prediction table  Tanaka and Johnston Equation Mandibular incisors mesiodistal width = 3,4,5 MD width 2 + 10.5 Upper incisors mesiodistal width 2 + 11  Procedure: The mesiodistal width of the mandibular permanent incisors is measured and divided by two For the mandibular arch add 10.5 mm to the result and for maxillary arch add 11 mm to the result to obtain the total estimated widths of the canines and premolars Compare the tooth widths predictions with the total measured arch length to obtain inadequacies in arch length