Inclusion criteria:  Above 20 years old The patient need dental implant surgery in maxilla The patient have at least complete canine to second molar at one side Periodontaliy healthy patients The patient could sign for the consent form.  Exclusion criteria:  patients can not receive dental implant surgery fuzzy palatal alveolar bone line all maxillary posterior teeth with metal crowns all posterior teeth are missing at one side over maxilla all maxillary posterior teeth with hyper-mobility Pregnancy